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Sample records for fluorophore chloro phenyl

  1. Synthesis and Biological Activity of 3-Chloro-1-(4-perimidine methylcarbonylamino-4-phenyl-azetidin-2-one

    Directory of Open Access Journals (Sweden)

    Dinesh R. Panchasara

    2009-01-01

    Full Text Available Perimidine-1-acetic acid hydrazide (1 undergoes facile condensation with aromatic aldehydes to afford the corresponding azomethine (i.e. Schiff base derivatives (2a-h in good yield. Cyclocondensation of compounds (2a-h with chloro acetyl chloride affords 3-chloro-1-(4-perimidine methylcarbonylamino-4-phenyl-azetidin-2-ones (3a-h. The structures of these compounds were established on the basis of analytical and spectral data. The newly synthesized compounds were evaluated for their antibacterial and antifungal activities.

  2. Poly[methyl(phenyl)silanediyl] modified with dansyl fluorophore: synthesis and photophysics

    Czech Academy of Sciences Publication Activity Database

    Cimrová, Věra; Výprachtický, Drahomír; Hörhold, H. H.

    2011-01-01

    Roč. 49, č. 10 (2011), s. 2233-2244 ISSN 0887-624X R&D Projects: GA MŠk(CZ) 1M06031; GA AV ČR IAA4050409 Institutional research plan: CEZ:AV0Z40500505 Keywords : conjugated polymers * dansyl fluorophore * polysilanes Subject RIV: JA - Electronics ; Optoelectronic s, Electrical Engineering Impact factor: 3.919, year: 2011

  3. Synthesis, characterization, antimicrobial and cytotoxic evaluation of a bidentate schiff base ligand: (5-chloro-2-((4-nitrobenzylidene)amino)phenyl)(phenyl)methanone and its transition metal complexes

    International Nuclear Information System (INIS)

    Anis, I.; Noreen, Z.

    2013-01-01

    A Schiff base ligand (SBL): ((5-chloro-2-)(4-nitrobenzylidene) amino) phenyl)(phenyl) methanone,, was synthesized from the reaction of 4-nitrobenzaldehyde and 2-amino-5-chlorobeznzophenone followed by complexation with transition metal (II) ions (1-5). Their structures were elucidated on the basis of infrared, 1H-NMR, FAB-MS spectral, elemental analyses and molar conductance data. The octahedral geometry for complexes (1-4) and square planar geometry for complex (5) was proposed on the basis of electronic and magnetic moment data. The non-electrolytic nature of the complexes (1-5) was suggested from the conductivity data. The complexes (1-5) showed higher in vitro antimicrobial activity and in vivo lethality to shrimp larvae than the parent Schiff base ligand. (author)

  4. Synthesis and Characterization of Ferroelectric Liquid Crystalline Organosiloxanes Containing 4-(4-undecanyloxy bi-phenyl-1-carboxyloxyphenyl (2S,3S-2-chloro-3-methylvalerate and 4-(4-undecanyloxybenzoyloxybiphenyl (2S,3S-2-chloro-3-methylvalerate

    Directory of Open Access Journals (Sweden)

    Chih-Hung Lin

    2013-10-01

    Full Text Available A series of new organosiloxane ferroelectric liquid crystalline (FLC materials have been synthesized, and their mesomorphic and physical properties have been characterized. Four new disiloxanes and trisiloxanes, containing biphenyl 4-hydroxybenzoate and phenyl 4-hydroxybiphenylcarboxylate as mesogenic units and eleven methylene unit as spacers and (2S,3S-2-chloro-3-methylvalerate unit as chiral end groups. The molecule, using three phenyl ring as a mesogenic unit, formulates much wider liquid crystalline phase temperature ranges than that of a two phenyl ring unit. The phenyl arrangement differences of mesogenic unit result in the greater differences of the liquid crystal phase formation. The siloxane molecule induction is helpful to the more regular smectic phase formation and smectic phase stabilization, such as chiral SC (SC* and SB phases. The siloxane molecule is helpful to reduce the phase transition temperature and broaden the liquid crystal temperature range of the SC* phase and, simultaneously, it will not induce chain crystallization phenomenon and dilute the Ps value. The synthesis and characterization of the new FLCs materials, which exhibit a room temperature SC* phase and higher spontaneous polarization are presented.

  5. Synthesis and Antifungal Activities of 5-(o-Hydroxy phenyl-2-[4'aryl-3'chloro-2'azetidinon-1-yl]-1,3,4-thiadiazole

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    Shiv K. Gupta

    2011-01-01

    Full Text Available New series of 5-(o-hydroxy phenyl-2-[4'aryl-3'chloro-2'azetidinon-1-yl]-1,3,4-thiadiazole have been synthesized and the structures of the new compounds were established on the basis of IR, 1H NMR spectral data. In vitro antifungal activity (MIC activity was evaluated and compared with standard drugs of ketoconazole. Compounds 3c in the series has shown interesting antifungal activity against both C. albicans and A. niger fungus. In the gratifying result, most of the compounds were found to have moderate antifungal activity.

  6. Extraction and spectrophotometric determination of vanadium(V) with N-hydroxy-N-m-tolyl-N'-(2-methyl-5-chloro)-phenyl-p-toluamidine hydrochloride in presence of salicylic, anthranilic and phthalic acids

    Energy Technology Data Exchange (ETDEWEB)

    Patel, K S; Deb, K K; Mishra, R [Ravishankar Univ., Raipur (India). Dept. of Chemistry

    1981-02-01

    The present work deals with the solvent extraction and simultaneous spectrophotometric determination of microgram quantities of vanadium(V) as mixed ligand complex with N-hydroxy-N-m-tolyl-N'-(2-methyl-5-chloro)-phenyl-p-toluamidine hydrochloride (HTMCPTH) and six carboxylic acids viz. salicylic, acetylsalicylic (aspirin), sulfosalicylic, anthranilic, N-phenyl-anthranilic and phthalic. The method presented here is simple, rapid, sensitive and reasonably selective.

  7. Extraction and spectrophotometric determination of vanadium(V) with N-hydroxy-N-m-tolyl-N'-(2-methyl-5-chloro)-phenyl-p-toluamidine hydrochloride in presence of salicylic, anthranilic and phthalic acids

    International Nuclear Information System (INIS)

    Patel, K.S.; Deb, K.K.; Mishra, R.

    1981-01-01

    The present work deals with the solvent extraction and simultaneous spectrophotometric determination of microgram quantities of vanadium(V) as mixed ligand complex with N-hydroxy-N-m-tolyl-N'-(2-methyl-5-chloro)-phenyl-p-toluamidine hydrochloride (HTMCPTH) and six carboxylic acids viz. salicylic, acetylsalicylic (aspirin), sulfosalicylic, anthranilic, N-phenyl-anthranilic and phthalic. The method presented here is simple, rapid, sensitive and reasonably selective. (author)

  8. 1-[(6-Chloro-3-pyridylmethyl]-N-(4-ethoxyphenyl-3-phenyl-1H-pyrazole-5-carboxamide

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    Zheng Tang

    2009-04-01

    Full Text Available In the title compound, C24H21ClN4O2, the pyrazole ring makes dihedral angles of 7.70 (11, 89.17 (11 and 40.68 (11° with the phenyl, pyridine and ethoxyphenyl rings, respectively. There are some intramolecular C—H...O and C—H...π bonds giving rigidity to the molecule, while weak intermolecular N—H...N and C—H...π hydrogen bonds link the molecules into a two-dimensional structure.

  9. Synthesis, structural, antibacterial and spectral studies of Co (II) complexes with salicylaldehyde and p-chloro-benzaldehyde 4-phenyl thiosemicarbazone

    International Nuclear Information System (INIS)

    Nur Nadia Dzulkifli; Yang Farina; Ibrahim Baba; Nazlina Ibrahim

    2012-01-01

    The Co(II) complexes derived from salicylaldehyde 4-phenyl thiosemicarbazone; SaOHtsc, p-chlorobenzaldehyde 4-phenyl thiosemicarbazone; ph-HClbtsc is reported and characterized based on elemental analysis, IR, magnetic susceptibility measurement, 1 H and 13 C NMR spectra. The Co(II) complexes have the molecular formula CoL 2 where the ligand corresponding to SaOHtsc and ph-HClbtsc. The elemental analysis for the ligands and complexes were in a good agreement with the theoretical values. The ligands coordinate to metal ions in different ways which is through mono negative bidentate or di negative tridentate. The magnetic susceptibility measurements showed that the CoL 2 complexes with ligand SaOHtsc are diamagnetic thus making this complexes suitable for NMR studies. The signals at the 10.04 ppm were assigned to N 2 H in the 1 H-NMR spectra of the free ligands was absent in the spectra of the complexes due to the deprotonation of the N 2 H and coordination to the metal centres. The absence of the band in IR spectrum which is assigned to v(N 2 -H) in the spectra of CoL 2 complexes is due to the deprotonation of the ligands upon complexation through azomethine nitrogen and thionic sulphur atom to metal ion. The thiosemicarbazones and its Co(II) complexes showed moderate inhibitory against bacteria Bacillus Subtilis, Staphylococcus Epidermis, Escherichia Coli and Proteus Mirabilis in 10 μg/ disc. (author)

  10. Crystal structures of nitrato-(2-[2-(1-pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) aquacopper and chloro-(2-[2-phenyl(pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) copper

    Energy Technology Data Exchange (ETDEWEB)

    Chumakov, Yu. M. [Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of); Paholnitcaia, A. Yu. [State University of Moldova (Moldova, Republic of); Petrenko, P. A. [Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of); Tsapkov, V. I., E-mail: vtsapkov@gmail.com [State University of Moldova (Moldova, Republic of); Poirier, D. [Centre Hospitalier Universitaire de Quebec (Canada); Gulea, A. P. [State University of Moldova (Moldova, Republic of)

    2015-01-15

    Two crystal modifications of nitrato-(2-[2-(1-pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) aquacopper (I and II) and two modifications of chloro-(2-[2-phenyl(pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) copper (III and IV) have been synthesized and studied by X-ray diffraction. In structures I and II, the copper atoms coordinate a monodeprotonated molecule of the organic ligand, nitrate ions, and a water molecule. In crystals of I, the complexes are monomeric, whereas complexes II are linked via nitrate ions to form polymeric chains. In both structures the coordination polyhedron of the copper atom can be described as a distorted tetragonal bipyramid—(4 + 1 + 1) in I and (4 + 2) in II. These coordination polyherdra have different compositions. In structures III and IV, the metal atoms coordinate a monodeprotonated (2-[2-phenyl(pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazole molecule and chloride ions. In III the complex-forming ion has square-planar coordination geometry, whereas structure IV consists of centrosymmetric dimers with two bridging chlorine atoms. It was found that nitrato-(2-[2-(1-pyridine-2-ylethylidene)hydrazine]-1,3-benzothiazolo) aquacopper possesses antitumor activity.

  11. Synthesis, crystal structure, vibrational profiling, DFT studies and molecular docking of N-(4-chloro-2-{[2-(1H-indol-2-ylcarbonyl) hydrazinyl](oxo)acetyl}phenyl)acetamide.DMSO: A new antiproliferative agent

    Science.gov (United States)

    Al-Wabli, Reem I.; Salman, Asmaa; Shyni, V.; Ghabbour, Hazem A.; Joe, I. Hubert; Almutairi, Maha S.; Maklad, Yousreya A.; Attia, Mohamed I.

    2018-03-01

    Cancer is one of the most serious health problems worldwide and it is considered the second major cause of mankind deaths. We report the synthesis and spectroscopic characterization of N-(4-chloro-2-{[2-(1H-indol-2-ylcarbonyl)hydrazinyl](oxo)acetyl}phenyl)acetamide (CICHOPA, 5) as a new antiproliferative glyoxylamide derivative. Molecular structure of CICHOPA (5) was unequivocally confirmed via X-ray analysis and it was crystallized in the monoclinic, P21/c, a = 14.3956 (4) Å, b = 8.9307 (3) Å, c = 34.9507 (10) Å, β = 94.439 (1)°, V = 4479.9 (2) Å3, Z = 8. The in vitro anticancer potential of the title molecule 5 was examined toward four types of human cancer cell lines. Vibrational profile of the CICHOPA molecule was investigated with the aid of density functional theory approach. Natural bond orbital, and natural population analyses as well as HOMO and LUMO molecular orbitals studies were carried out in order to explore the possible intermolecular delocalization or hyperconjugation in the title compound. The binding mode of compound 5 to its target protein was predicted through a molecular docking investigation. The in vitro antiproliferative activity of the title compound 5 was examined against four human cancer cell lines and showed growth inhibitory activity at concentrations of 25 and 50 μM.

  12. 6-Chloro-3-[5-(3-methoxy-8-methyl-4-quinolyl-1-phenyl-4,5-dihydro-1H-pyrazol-3-yl]-2-methyl-4-phenylquinoline

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    Hoong-Kun Fun

    2009-11-01

    Full Text Available In the title compound, C36H29ClN4O, the dihydropyrazole ring adopts an envelope conformation. The two quinoline ring systems (r.m.s. deviations = 0.029 and 0.018 Å are oriented at a dihedral angle of 71.43 (4°. One of the quinoline rings makes a dihedral angle of 65.40 (7° with the phenyl substituent. In the crystal, molecules are linked into chains along the b axis by intermolecular C—H...N hydrogen bonds. In addition, C—H...π and π–π [centroid–centroid distance = 3.7325 (8 Å] interactions are observed.

  13. Radiosynthesis of 7-chloro-N, N-dimethyl-5-[11C] methyl-4-oxo-3-phenyl-3, 5-dihydro-4H pyridazino [4, 5-b]indole-1-acetamide, [11C]SSR180575, a novel radioligand for imaging the TSPO (peripheral benzodiazepine receptor) with PET

    International Nuclear Information System (INIS)

    Thominiaux, C.; Damont, A.L.; Kuhnast, B.; Demphel, St.; Le Helleix, St.; Chauveau, F.; Boutin, H.; Van Camp, N.; Boisgard, R.; Tavitian, B.; Dolle, F.; Boisnard, S.; Rivron, L.; Roy, S.; Allen, J.; Chauveau, F.; Boutin, H.; Van Camp, N.; Boisgard, R.; Tavitian, B.; Rooney, T.; Benavides, J.; Hantraye, Ph.

    2010-01-01

    SSR180575 (7-chloro-N, N, 5-trimethyl-4-oxo-3-phenyl-3, 5-dihydro-4H-pyridazino [4, 5-b]indole-1-acetamide) is the lead compound of an original pyridazino-indole series of potent and highly selective TSPO (peripheral benzodiazepine receptor) ligands. Isotopic labeling of SSR180575 with the short-lived positron-emitter carbon-11 (T1/2: 20.38 min) at its 5-methyl-pyridazino[4, 5-b]indole moiety as well as at its N, N-dimethylacetamide function by methylation of the corresponding nor-analogues was investigated. Best results in terms of radiochemical yields and purities were obtained for the preparation of [indole-N-methyl- 11 C]SSR180575, where routine production batches of 4.5-5.0 GBq of radiochemically pure (499%) i.v. injectable solutions (specific radioactivities: 50-90 GBq/μmol) could be prepared within a total synthesis time of 25 min (HPLC purification included) starting from a 55 GBq [ 11 C]CO 2 cyclotron production batch (non decay-corrected overall radiochemical yields: 8-9%). The process comprises (1) trapping at -10 C of [ 11 C]methyl triflate in DMF (300 μl) containing 0.2-0.3 mg of the indole precursor for labeling and 4 mg of K 2 CO 3 (excess); (2) heating at 120 C for 3 min; (3) dilution of the residue with 0.5 ml of the HPLC mobile phase and (4) purification using semi-preparative reversed phase HPLC (Zorbax R SB-C-18). In vivo pharmacological properties of [indole-N-methyl- 11 C]SSR180575 as a candidate for imaging neuro-inflammation with positron emission tomography are currently evaluated. (authors)

  14. Optical indicators based on environment sensitive fluorophors

    Energy Technology Data Exchange (ETDEWEB)

    Shakhsher, Z.M.; Seitz, W.R. (Univ. of New Hampshire, Durham, NC (USA))

    1990-01-01

    The authors are interested in the development of optical indicators based on environment sensitive fluorophors. The fluorophor is immobilized on a solid substrate. Interaction with analyte modifies the fluorophor environment, leading to a shift in the distribution of emission wavelengths. Because the indicator is based on spectral shift, it is possible to relate analyte concentration to a ratio of intensities at two different wavelengths. This parameter is insensitive to instrumental drift and slow loss of indicator. Two indicator systems have been investigated. Both involve dansyl derivation, i.e., derivatives of 5-dimethylamino-1-naphthalene sulfonic acid.

  15. 5-Chloro-2-methyl-3-phenylsulfonyl-1-benzofuran

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    Hong Dae Choi

    2008-07-01

    Full Text Available The title compound, C15H11ClO3S, was prepared by the oxidation of 5-chloro-2-methyl-3-phenylsulfanyl-1-benzofuran with 3-chloroperoxybenzoic acid. There are two symmetry-independent molecules in the asymmetric unit. The dihedral angles formed by the phenyl ring and the plane of the benzofuran system are 77.80 (8 and 78.34 (8°. The crystal structure is stabilized by aromatic π–π stacking interactions between the furan ring and the benzene rings of neighbouring benzofuran fragments from two symmetry-independent molecules; the centroid–centroid distances within the stacks are 3.689 (4, 3.702 (4, 3.825 (4 and 3.826 (4 Å. Additionally, the stacked molecules exhibit inter- and intramolecular C—H...O interactions.

  16. Deuterium isotopic effects connected with unimolecular and concerted mechanisms. The case of 1-deutero-2-chloro alcohols

    International Nuclear Information System (INIS)

    Jambon, C.

    1962-01-01

    After a bibliographic analysis of the probable causes of isotopic effects and their comparison, with the simplifications provided by the athermal model, a discussion of the isotopic effect of deuterium in organic molecules in terms of structural influences is presented, showing the important role of the C-D bond length which is shorter than the C-H bond length, and of the D atom's Van der Waals radius, shorter than that of the H atom. Kinetic measurements were carried out on some reactions involving the mechanisms proposed: unimolecular ionizations and halogen concentrates. The structural models chosen are: 2-chloro-cyclo-hexanols cis and trans 1-H and 2-D; 2-chloro-cyclo-pentanols cis trans 1-H and 1-D; 1-phenyl-l-chloro-2-propanol threo 2-H and 2-D. (author) [fr

  17. Deuterium isotopic effects connected with unimolecular and concerted mechanisms. The case of 1-deutero-2-chloro alcohols; Effets isotopiques du deuterium attaches a des mecanismes unimoleculaires et concertes. Cas des deutero-1-chloro-2 alcools

    Energy Technology Data Exchange (ETDEWEB)

    Jambon, C

    1962-07-01

    After a bibliographic analysis of the probable causes of isotopic effects and their comparison, with the simplifications provided by the athermal model, a discussion of the isotopic effect of deuterium in organic molecules in terms of structural influences is presented, showing the important role of the C-D bond length which is shorter than the C-H bond length, and of the D atom's Van der Waals radius, shorter than that of the H atom. Kinetic measurements were carried out on some reactions involving the mechanisms proposed: unimolecular ionizations and halogen concentrates. The structural models chosen are: 2-chloro-cyclo-hexanols cis and trans 1-H and 2-D; 2-chloro-cyclo-pentanols cis trans 1-H and 1-D; 1-phenyl-l-chloro-2-propanol threo 2-H and 2-D. (author) [French] Apres une analyse bibliographique des causes probables d'effets isotopiques et leur comparaison, avec les simplifications qu'apporte le modele athermique, on a entrepris l'etude de la discussion isotopique du deuterium dans des molecules organiques en termes d'influences structurelles, cherchant a degager le role important de la longueur de la liaison C-D plus courte que C-H, et du rayon de Van der Waals de l'atome de D plus petit que celui de H. On a effectue des mesures cinetiques sur quelques reactions invoquant les mecanismes envisages: ionisations unimoleculaires et concentrees d'halogenes. Les modeles structuraux choisis sont: chloro 2 - cyclohexanols cis et trans H 1 et D 1; chloro 2 - cyclopentanols cis et trans H 1 et D 1; phenyl 1 - chloro 1 - propanol 2 threo H 2 et D 2. (auteur)

  18. Deuterium isotopic effects connected with unimolecular and concerted mechanisms. The case of 1-deutero-2-chloro alcohols; Effets isotopiques du deuterium attaches a des mecanismes unimoleculaires et concertes. Cas des deutero-1-chloro-2 alcools

    Energy Technology Data Exchange (ETDEWEB)

    Jambon, C

    1962-07-01

    After a bibliographic analysis of the probable causes of isotopic effects and their comparison, with the simplifications provided by the athermal model, a discussion of the isotopic effect of deuterium in organic molecules in terms of structural influences is presented, showing the important role of the C-D bond length which is shorter than the C-H bond length, and of the D atom's Van der Waals radius, shorter than that of the H atom. Kinetic measurements were carried out on some reactions involving the mechanisms proposed: unimolecular ionizations and halogen concentrates. The structural models chosen are: 2-chloro-cyclo-hexanols cis and trans 1-H and 2-D; 2-chloro-cyclo-pentanols cis trans 1-H and 1-D; 1-phenyl-l-chloro-2-propanol threo 2-H and 2-D. (author) [French] Apres une analyse bibliographique des causes probables d'effets isotopiques et leur comparaison, avec les simplifications qu'apporte le modele athermique, on a entrepris l'etude de la discussion isotopique du deuterium dans des molecules organiques en termes d'influences structurelles, cherchant a degager le role important de la longueur de la liaison C-D plus courte que C-H, et du rayon de Van der Waals de l'atome de D plus petit que celui de H. On a effectue des mesures cinetiques sur quelques reactions invoquant les mecanismes envisages: ionisations unimoleculaires et concentrees d'halogenes. Les modeles structuraux choisis sont: chloro 2 - cyclohexanols cis et trans H 1 et D 1; chloro 2 - cyclopentanols cis et trans H 1 et D 1; phenyl 1 - chloro 1 - propanol 2 threo H 2 et D 2. (auteur)

  19. Crystal structures of 5-amino-N-phenyl-3H-1,2,4-di-thia-zol-3-iminium chloride and 5-amino-N-(4-chloro-phen-yl)-3H-1,2,4-di-thia-zol-3-iminium chloride monohydrate.

    Science.gov (United States)

    Yeo, Chien Ing; Tan, Yee Seng; Tiekink, Edward R T

    2015-10-01

    The crystal and mol-ecular structures of the title salt, C8H8N3S2 (+)·Cl(-), (I), and salt hydrate, C8H7ClN3S2 (+)·Cl(-)·H2O, (II), are described. The heterocyclic ring in (I) is statistically planar and forms a dihedral angle of 9.05 (12)° with the pendant phenyl ring. The comparable angle in (II) is 15.60 (12)°, indicating a greater twist in this cation. An evaluation of the bond lengths in the H2N-C-N-C-N sequence of each cation indicates significant delocalization of π-electron density over these atoms. The common feature of the crystal packing in (I) and (II) is the formation of charge-assisted amino-N-H⋯Cl(-) hydrogen bonds, leading to helical chains in (I) and zigzag chains in (II). In (I), these are linked by chains mediated by charge-assisted iminium-N(+)-H⋯Cl(-) hydrogen bonds into a three-dimensional architecture. In (II), the chains are linked into a layer by charge-assisted water-O-H⋯Cl(-) and water-O-H⋯O(water) hydrogen bonds with charge-assisted iminium-N(+)-H⋯O(water) hydrogen bonds providing the connections between the layers to generate the three-dimensional packing. In (II), the chloride anion and water mol-ecules are resolved into two proximate sites with the major component being present with a site occupancy factor of 0.9327 (18).

  20. Synthesis and spectroscopic characterization of Y-shaped fluorophores with an imidazole core containing crown ether moieties

    International Nuclear Information System (INIS)

    Doğru, Ümit; Öztürk Ürüt, Gülsiye; Bayramin, Dilek

    2015-01-01

    In this study three new Y-shaped fluorophores, 4,5-(2,2'-diphenyl)vinyl-{2-[(1,4,7,10-tetraoxa-13-azacyclopentadecyl) phenyl]}-1H-imidazole (1a), 4,5-{[2,2'-bis(4-methoxyphenyl)vinyl]-[2-(1,4,7,10-tetraoxa-13- azacyclopentadecyl)-phenyl]}-1H-imidazole (1b) and 4,5-(2,2'-diphenyl)vinyl-{2-(1,4,7,10,13-benzopentaoxacyclopentadecyl)} -1H-imidazole (1c) were synthesized. 1,6-Diphenylhexa-1,5-diene-3,4-dione (2a) and 1,6-bis(4-methoxyphenyl)hexa-1,5-diene-3,4-dione (2b) were synthesized as preliminary fluorophores and then reacted with 4-formylbenzo-aza-15-crown-5 (3a) and 4-formylbenzo-15-crown-5 (3b) to obtain the three Y-shaped fluorophores 1a, 1b and 1c. 4-formylbenzo-aza-15-crown-5 and 4-formylbenzo-15-crown-5 intermediates were synthesized with Vilsmeier–Haack reaction. The photophysical properties such as maximum absorption wavelengths, maximum emission wavelengths, Stokes' shifts, singlet energies, fluorescence quantum yields and photostabilities of the compounds were investigated by measuring absorption and emission spectra in a series of solvents of varying polarities of toluene (TOL), dichloromethane (DCM), tetrahydrofuran (THF), ethyl acetate (EA), acetonitrile (ACN), and N,N-dimethylformamide (DMF). The three compounds 1a, 1b and 1c exhibited emission maxima in the 412–677 nm range. All the derivatives synthesized exhibited excellent photostability in all the solvents tested. - Highlights: • Three new Y-shaped fluorophores were synthesized for the first time. • Their absorption and emission properties were investigated. • All the derivatives synthesized exhibited excellent photostability

  1. Synthesis and spectroscopic characterization of Y-shaped fluorophores with an imidazole core containing crown ether moieties

    Energy Technology Data Exchange (ETDEWEB)

    Doğru, Ümit; Öztürk Ürüt, Gülsiye, E-mail: gulsiye.ozturk@deu.edu.tr; Bayramin, Dilek

    2015-07-15

    In this study three new Y-shaped fluorophores, 4,5-(2,2'-diphenyl)vinyl-{2-[(1,4,7,10-tetraoxa-13-azacyclopentadecyl) phenyl]}-1H-imidazole (1a), 4,5-{[2,2'-bis(4-methoxyphenyl)vinyl]-[2-(1,4,7,10-tetraoxa-13- azacyclopentadecyl)-phenyl]}-1H-imidazole (1b) and 4,5-(2,2'-diphenyl)vinyl-{2-(1,4,7,10,13-benzopentaoxacyclopentadecyl)} -1H-imidazole (1c) were synthesized. 1,6-Diphenylhexa-1,5-diene-3,4-dione (2a) and 1,6-bis(4-methoxyphenyl)hexa-1,5-diene-3,4-dione (2b) were synthesized as preliminary fluorophores and then reacted with 4-formylbenzo-aza-15-crown-5 (3a) and 4-formylbenzo-15-crown-5 (3b) to obtain the three Y-shaped fluorophores 1a, 1b and 1c. 4-formylbenzo-aza-15-crown-5 and 4-formylbenzo-15-crown-5 intermediates were synthesized with Vilsmeier–Haack reaction. The photophysical properties such as maximum absorption wavelengths, maximum emission wavelengths, Stokes' shifts, singlet energies, fluorescence quantum yields and photostabilities of the compounds were investigated by measuring absorption and emission spectra in a series of solvents of varying polarities of toluene (TOL), dichloromethane (DCM), tetrahydrofuran (THF), ethyl acetate (EA), acetonitrile (ACN), and N,N-dimethylformamide (DMF). The three compounds 1a, 1b and 1c exhibited emission maxima in the 412–677 nm range. All the derivatives synthesized exhibited excellent photostability in all the solvents tested. - Highlights: • Three new Y-shaped fluorophores were synthesized for the first time. • Their absorption and emission properties were investigated. • All the derivatives synthesized exhibited excellent photostability.

  2. Noval 1-substituted-3,5-dimethyl-4-[(substituted phenyl diazenyl] pyrazole derivatives: Synthesis and pharmacological activity

    Directory of Open Access Journals (Sweden)

    Sabir Hussain

    2015-05-01

    Full Text Available Several-1-carbothioamide-3,5-dimethyl-4-[(substituted phenyl diazenyl] pyrazoles 2a–d, 1-(pyridine-4-ylcarbonyl-3,5-dimethyl-4-[(substituted phenyl diazenyl] pyrazoles 3a–d, 1-(5-chloro-6-fluoro-1,3-benzothiazole-2-ylthiocarbamoyl-3,5-dimethyl-4-[(substituted phenyl diazenyl] pyrazoles 4a–d and 1-[(1,2,4-triazole-4-yl carbothioamide]-3,5-dimethyl-4-[(substituted phenyl diazenyl] pyrazoles 5a–d were synthesized. The structures of the newly synthesized compounds were supported by IR, 1H NMR and mass spectral data. These compounds were investigated for their, anti-inflammatory, analgesic, ulcerogenic, lipid peroxidation, antibacterial and antifungal activities. Some of the synthesized compounds showed potent anti-inflammatory activity along with minimal ulcerogenic effect and lipid peroxidation, compared to ibuprofen and flurbiprofen. Some of the tested compounds also showed moderate antimicrobial activity against tested bacterial and fungal strains.

  3. Highly charged cyanine fluorophores for trafficking scaffold degradation

    International Nuclear Information System (INIS)

    Owens, Eric A; Alyabyev, Sergey; Henary, Maged; Hyun, Hoon; Kim, Soon Hee; Lee, Jeong Heon; Park, GwangLi; Ashitate, Yoshitomo; Choi, Jungmun; Hong, Gloria H; Choi, Hak Soo; Lee, Sang Jin; Khang, Gilson

    2013-01-01

    Biodegradable scaffolds have been extensively used in the field of tissue engineering and regenerative medicine. However, noninvasive monitoring of in vivo scaffold degradation is still lacking. In order to develop a real-time trafficking technique, a series of meso-brominated near-infrared (NIR) fluorophores were synthesized and conjugated to biodegradable gelatin scaffolds. Since the pentamethine cyanine core is highly lipophilic, the side chain of each fluorophore was modified with either quaternary ammonium salts or sulfonate groups. The physicochemical properties such as lipophilicity and net charge of fluorophores played a key role in the fate of NIR-conjugated scaffolds in vivo after biodegradation. The positively charged fluorophore-conjugated scaffold fragments were found in salivary glands, lymph nodes, and most of the hepatobiliary excretion route. However, halogenated fluorophores intensively accumulated into lymph nodes and the liver. Interestingly, balanced-charged gelatin scaffolds were degraded into urine in a short period of time. These results demonstrate that the noninvasive optical imaging using NIR fluorophores can be useful for the translation of biodegradable scaffolds into the clinic. (paper)

  4. Why Do Simple Molecules with "Isolated" Phenyl Rings Emit Visible Light?

    Science.gov (United States)

    Zhang, Haoke; Zheng, Xiaoyan; Xie, Ni; He, Zikai; Liu, Junkai; Leung, Nelson L C; Niu, Yingli; Huang, Xuhui; Wong, Kam Sing; Kwok, Ryan T K; Sung, Herman H Y; Williams, Ian D; Qin, Anjun; Lam, Jacky W Y; Tang, Ben Zhong

    2017-11-15

    π-Bonds connected with aromatic rings were generally believed as the standard structures for constructing highly efficient fluorophores. Materials without these typical structures, however, exhibited only low fluorescence quantum yields and emitted in the ultraviolet spectral region. In this work, three molecules, namely bis(2,4,5-trimethylphenyl)methane, 1,1,2,2-tetrakis(2,4,5-trimethylphenyl)ethane, and 1,1,2,2-tetraphenylethane, with nonconjugated structures and isolated phenyl rings were synthesized and their photophysical properties were systematically investigated. Interestingly, the emission spectra of these three molecules could be well extended to 600 nm with high solid-state quantum yields of up to 70%. Experimental and theoretical analyses proved that intramolecular through-space conjugation between the "isolated" phenyl rings played an important role for this abnormal phenomenon.

  5. Leaching of dieldrin, permethrin, phenyl urea and 4-CL phenyl urea pesticides from soil

    International Nuclear Information System (INIS)

    Onal, G.

    1978-01-01

    Leaching of four 14 C-labelled pesticides (dieldrin, permethrin, phenyl urea and 4-Cl phenyl urea) were investigated. It was found that dieldrin and permethrin were not leached from soil but adsorbed by the soil; phenyl urea and 4-CL phenyl urea were leached to a 7.5 cm depth

  6. 2-Chloro-N-(3-chlorophenylbenzamide

    Directory of Open Access Journals (Sweden)

    B. Thimme Gowda

    2008-07-01

    Full Text Available In the structure of the the title compound, C13H9Cl2NO, the N—H and C=O groups are mutually trans. Furthermore, the conformation of the C=O group is syn to the ortho-chloro group in the benzoyl ring, while the N—H bond is anti to the meta-chloro group in the aniline ring. The amide group forms dihedral angles of 89.11 (19 and 22.58 (37°, respectively, with the benzoyl and aniline rings, while the benzoyl and aniline rings form a dihedral angle of 69.74 (14°. The molecules are linked into infinite chains through intermolecular N—H...O hydrogen bonds.

  7. 4-Chloro-N-o-tolylbenzamide

    Directory of Open Access Journals (Sweden)

    Hiroyuki Ishida

    2008-10-01

    Full Text Available In the molecule of the title compound, C14H12ClNO, the two benzene rings are close to coplanar [dihedral angle = 7.85 (4°]. The amide N—C=O plane makes dihedral angles of 34.04 (4 and 39.90 (3°, respectively, with the 4-chloro- and 2-methylphenyl rings. In the crystal structure, intermolecular N—H...O hydrogen bonds link the molecules into chains.

  8. Single Molecule Study of Photoconversion and Spectral Heterogeneities of Fluorophores

    DEFF Research Database (Denmark)

    Liao, Zhiyu

    of conformational changes and dynamics. The photophysical properties of organic dyes directly determine the quality of the experiments. So the better understanding of the photophysical properties of organic dyes, the better we are able to design the experiments and interpret the data, especially in single molecule...... important criteria for a good fluorophore. Improving the photostability of organic dyes by designing the structure is always a difficult task for organic chemists. It requires a comprehensive understanding of the mechanism of the photobleaching behavior of fluorophores. It is the aim of this work...... to understand the mechanisms of photobleaching behaviors of organic dyes, terrylene diimide (TDI) and amino-trioxatriangulenium dye (A3-TOTA+). Photobleaching is usually seen as permanent loss of fluorescence. In this work, we show that organic fluorophores can be converted into another chemical compound after...

  9. Bright photoactivatable fluorophores for single-molecule imaging.

    Science.gov (United States)

    Grimm, Jonathan B; English, Brian P; Choi, Heejun; Muthusamy, Anand K; Mehl, Brian P; Dong, Peng; Brown, Timothy A; Lippincott-Schwartz, Jennifer; Liu, Zhe; Lionnet, Timothée; Lavis, Luke D

    2016-12-01

    Small-molecule fluorophores are important tools for advanced imaging experiments. We previously reported a general method to improve small, cell-permeable fluorophores which resulted in the azetidine-containing 'Janelia Fluor' (JF) dyes. Here, we refine and extend the utility of these dyes by synthesizing photoactivatable derivatives that are compatible with live-cell labeling strategies. Once activated, these derived compounds retain the superior brightness and photostability of the JF dyes, enabling improved single-particle tracking and facile localization microscopy experiments.

  10. Energy transfer from a fluorescent hydrogel to a hosted fluorophore

    NARCIS (Netherlands)

    Montalti, Marco; Dolci, Luisa Stella; Prodi, Luca; Zaccheroni, Nelsi; Stuart, Marc C.A.; van Bommel, Kjeld C.; Friggeri, Arianna

    2006-01-01

    The fluorescent properties of a new 1,3,5-cyclohexyltricarboxamide-based low-molecular-weight hydrogelator (1) derivatized with one hydrophobic fluorophore and two hydrophilic substituents have been investigated. Gels of I are composed of long, nonbranched fibers of uniform diameter, as shown by

  11. Exposure characteristics of positive tone electron beam resist containing p-chloro-α-methylstyrene

    Science.gov (United States)

    Ochiai, Shunsuke; Takayama, Tomohiro; Kishimura, Yukiko; Asada, Hironori; Sonoda, Manae; Iwakuma, Minako; Hoshino, Ryoichi

    2017-07-01

    The positive tone resist consisted of methyl-α-chloroacrylate (ACM) and α-methylstyrene (MS) has higher sensitivity and higher dry etching resistance than poly (methylmethacrylate) (PMMA) due to the presence of a chlorine atom and a phenyl group. Copolymers consisted of ACM and p-chloro-α-methylstyrene (PCMS), where the additional chlorine atom is introduced in phenyl group compared with ACM-MS resist are synthesized and their exposure characteristics are investigated. ACM-PCMS resist with the ACM:PCMS composition ratio of 49:51 indicates the high solubility for amyl acetate developer. As the ACM composition ratio increases, the solubility of ACM-PCMS resist is suppressed. In both ACM-PCMS and ACM-MS resists, the sensitivity decreases while the contrast increases with increasing ACM ratio. When the composition ratio of ACM:PCMS is 69:31, 100/100 nm line and space pattern having a good shape is obtained at 120 μC/cm2 which is comparable to the required exposure dose for conventional ACM-MS resist with ACM:MS=50:50. Dry etching resistance of ACM:PCMS resists for Ar gas is also presented.

  12. L-shaped benzimidazole fluorophores: synthesis, characterization and optical response to bases, acids and anions.

    Science.gov (United States)

    Lirag, Rio Carlo; Le, Ha T M; Miljanić, Ognjen Š

    2013-05-14

    Nine L-shaped benzimidazole fluorophores have been synthesized, computationally evaluated and spectroscopically characterized. These "half-cruciform" fluorophores respond to bases, acids and anions through changes in fluorescence that vary from moderate to dramatic.

  13. 21 CFR 177.2210 - Ethylene polymer, chloro-sulfonated.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ethylene polymer, chloro-sulfonated. 177.2210... as Components of Articles Intended for Repeated Use § 177.2210 Ethylene polymer, chloro-sulfonated. Ethylene polymer, chlorosulfonated as identified in this section may be safely used as an article or...

  14. 78 FR 18999 - Prospective Grant of Start-Up Exclusive License: Photosensitizing Antibody-Fluorophore Conjugates...

    Science.gov (United States)

    2013-03-28

    ...-Up Exclusive License: Photosensitizing Antibody-Fluorophore Conjugates for Photoimmunotherapy AGENCY...-205-2010/0-US-01), and entitled ``Photosensitizing Antibody- Fluorophore Conjugates,'' to Aspyrian... invention. The field of use may be limited to ``use of photosensitizing antibody-fluorophore conjugate by...

  15. NIR FRET Fluorophores for Use as an Implantable Glucose Biosensor

    Directory of Open Access Journals (Sweden)

    Majed DWEIK

    2008-12-01

    Full Text Available Development of an in vivo optical sensor requires the utilization of Near Infra Red (NIR fluorophores due to their ability to operate within the biological tissue window. Alexa Fluor 750 (AF750 and Alexa Fluor 680 (AF680 were examined as potential NIR fluorophores for an in vivo fluorescence resonance energy transfer (FRET glucose biosensor. AF680 and AF750 found to be a FRET pair and percent energy transfer was calculated. Next, the tested dye pair was utilized in a competitive binding assay in order to detect glucose. Concanavalin A (Con A and dextran have binding affinity, but in the presence of glucose, glucose displaces dextran due to its higher affinity to Con A than dextran. Finally, the percent signal transfer through porcine skin was examined. The results showed with approximately 4.0 mm porcine skin thickness, 1.98 % of the fluorescence was transmitted and captured by the detector.

  16. Fluorophore-based sensor for oxygen radicals in processing plasmas

    International Nuclear Information System (INIS)

    Choudhury, Faraz A.; Shohet, J. Leon; Sabat, Grzegorz; Sussman, Michael R.; Nishi, Yoshio

    2015-01-01

    A high concentration of radicals is present in many processing plasmas, which affects the processing conditions and the properties of materials exposed to the plasma. Determining the types and concentrations of free radicals present in the plasma is critical in order to determine their effects on the materials being processed. Current methods for detecting free radicals in a plasma require multiple expensive and bulky instruments, complex setups, and often, modifications to the plasma reactor. This work presents a simple technique that detects reactive-oxygen radicals incident on a surface from a plasma. The measurements are made using a fluorophore dye that is commonly used in biological and cellular systems for assay labeling in liquids. Using fluorometric analysis, it was found that the fluorophore reacts with oxygen radicals incident from the plasma, which is indicated by degradation of its fluorescence. As plasma power was increased, the quenching of the fluorescence significantly increased. Both immobilized and nonimmobilized fluorophore dyes were used and the results indicate that both states function effectively under vacuum conditions. The reaction mechanism is very similar to that of the liquid dye

  17. Fluorophore-based sensor for oxygen radicals in processing plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Choudhury, Faraz A.; Shohet, J. Leon, E-mail: shohet@engr.wisc.edu [Plasma Processing and Technology Laboratory and Department of Electrical and Computer Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Sabat, Grzegorz; Sussman, Michael R. [Department of Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Nishi, Yoshio [Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States)

    2015-11-15

    A high concentration of radicals is present in many processing plasmas, which affects the processing conditions and the properties of materials exposed to the plasma. Determining the types and concentrations of free radicals present in the plasma is critical in order to determine their effects on the materials being processed. Current methods for detecting free radicals in a plasma require multiple expensive and bulky instruments, complex setups, and often, modifications to the plasma reactor. This work presents a simple technique that detects reactive-oxygen radicals incident on a surface from a plasma. The measurements are made using a fluorophore dye that is commonly used in biological and cellular systems for assay labeling in liquids. Using fluorometric analysis, it was found that the fluorophore reacts with oxygen radicals incident from the plasma, which is indicated by degradation of its fluorescence. As plasma power was increased, the quenching of the fluorescence significantly increased. Both immobilized and nonimmobilized fluorophore dyes were used and the results indicate that both states function effectively under vacuum conditions. The reaction mechanism is very similar to that of the liquid dye.

  18. 3-Substituted 2-phenyl-indoles

    DEFF Research Database (Denmark)

    Johansson, Karl Henrik; Jørgensen, T.B.; Gloriam, D.E.

    2013-01-01

    -indoles with a variety of substituents at the indole 3-position. Herein we describe the development of optimised and efficient synthetic routes to a series of new 2-phenyl-indole building blocks 3 to 9 and show that these can be used to generate a broad variety of 3-substituted 2-phenyl-indoles of interest to medicinal...

  19. Conjugate Addition of Nucleophiles to the Vinyl Function of 2-Chloro-4-vinylpyrimidine Derivatives

    Directory of Open Access Journals (Sweden)

    Lucjan Strekowski

    2010-03-01

    Full Text Available Conjugate addition reaction of various nucleophiles across the vinyl group of 2-chloro-4-vinylpyrimidine, 2-chloro-4-(1-phenylvinylpyrimidine and 2-chloro-4-vinylquinazoline provides the corresponding 2-chloro-4-(2-substituted ethylpyrimidines and 2-chloro-4-(2-substituted ethylquinazolines. Treatment of these products, without isolation, with N-methylpiperazine results in nucleophilic displacement of chloride and yields the corresponding 2,4-disubstituted pyrimidines and quinazolines.

  20. Selective bromination of 4-chloro-1-indanone and synthesis of (4-chloro-2, 3-dihydro-1H-indene-2-yl)methanamine

    OpenAIRE

    Jasouri, S.; Khalafy, J.; Badali, M.; Piltan, M.

    2010-01-01

    The synthesis of 4-chloro-1-indanone in four steps from 2-chlorobenzaldehyde was investigated. Bromination of this compound under various conditions occurred in the cyclopentanone ring, producing mono- and dibromo derivatives. Cyanation of 2-bromo-4-chloro-1-indanone followed by reduction gave (4-chloro-2, 3-dihydro-1H-indene-2-yl)methanamine in quantitative yield.

  1. The origin of luminescence from di[4-(4-diphenylaminophenyl)phenyl]sulfone (DAPSF), a blue light emitter: an X-ray excited optical luminescence (XEOL) and X-ray absorption near edge structure (XANES) study.

    Science.gov (United States)

    Zhang, Duo; Zhang, Hui; Zhang, Xiaohong; Sham, Tsun-Kong; Hu, Yongfeng; Sun, Xuhui

    2016-03-07

    The electronic structure and optical properties of di[4-(4-diphenylaminophenyl)phenyl]sulfone (denoted as DAPSF), a highly efficient fluorophor, have been investigated using X-ray excited optical luminescence (XEOL) and X-ray absorption near edge structure (XANES) spectroscopy at excitation energies across the C, N, O K-edges and the sulfur K-edge. The results indicate that the blue luminescence is mainly related to the sulfur functional group.

  2. Dual Mode Fluorophore-Doped Nickel Nitrilotriacetic Acid-Modified Silica Nanoparticles Combine Histidine-Tagged Protein Purification with Site-Specific Fluorophore Labeling

    OpenAIRE

    Kim, Sung Hoon; Jeyakumar, M.; Katzenellenbogen, John A.

    2007-01-01

    We present the first example of a fluorophore-doped nickel chelate surface- modified silica nanoparticle that functions in a dual mode, combining histidine-tagged protein purification with site-specific fluorophore labeling. Tetramethylrhodamine (TMR)-doped silica nanoparticles, estimated to contain 700–900 TMRs per ca. 23-nm particle, were surface modified with nitrilotriacetic acid (NTA), producing TMR-SiO2-NTA-Ni+2. Silica-embedded TMR retains very high quantum yield, is resistant to quenc...

  3. N-(2-Chlorophenyl-2-({5-[4-(methylsulfanylbenzyl]-4-phenyl-4H-1,2,4-triazol-3-yl}sulfanylacetamide

    Directory of Open Access Journals (Sweden)

    Hoong-Kun Fun

    2011-08-01

    Full Text Available In the title molecule, C24H21ClN4OS2, the central 1,2,4-triazole ring forms dihedral angles of 89.05 (9, 86.66 (9 and 82.70 (10° with the chloro-substituted benzene ring, the methylsulfanyl-substituted benzene ring and the phenyl ring, respectively. In the crystal, molecules are linked into sheets parallel to (100 by intermolecular N—H...N and weak C—H...O hydrogen bonds.

  4. Identification of endogenous fluorophores in the photoreceptors using autofluorescence spectroscopy

    Science.gov (United States)

    Zhao, Lingling; Qu, Junle; Niu, Hanben

    2007-11-01

    In this paper, we present our investigation on the identification of endogenous fluorophores in photoreceptors using autofluorescence spectroscopy, which is performed with an inverted laser scanning confocal microscope equipped with an Argon ion laser and a GreNe laser. In our experiments, individual cones and rods are clearly resolved even in freshly prepared retina samples, without slicing or labeling. The experiment results show that autofluorescence spectrum of the photoreceptors has three peaks approximately at 525nm, 585nm and 665nm. Furthermore, the brightest autofluorescence originates from the photoreceptor outer segments. We can, therefore, come to a conclusion that the peaks at 525nm, 585nm are corresponding to FAD and A2-PE, respectively, which are distributed in the photoreceptor outer segments.

  5. Probing protein-lipid interactions by FRET between membrane fluorophores

    Science.gov (United States)

    Trusova, Valeriya M.; Gorbenko, Galyna P.; Deligeorgiev, Todor; Gadjev, Nikolai

    2016-09-01

    Förster resonance energy transfer (FRET) is a powerful fluorescence technique that has found numerous applications in medicine and biology. One area where FRET proved to be especially informative involves the intermolecular interactions in biological membranes. The present study was focused on developing and verifying a Monte-Carlo approach to analyzing the results of FRET between the membrane-bound fluorophores. This approach was employed to quantify FRET from benzanthrone dye ABM to squaraine dye SQ-1 in the model protein-lipid system containing a polycationic globular protein lysozyme and negatively charged lipid vesicles composed of phosphatidylcholine and phosphatidylglycerol. It was found that acceptor redistribution between the lipid bilayer and protein binding sites resulted in the decrease of FRET efficiency. Quantification of this effect in terms of the proposed methodology yielded both structural and binding parameters of lysozyme-lipid complexes.

  6. A simple and versatile design concept for fluorophore derivatives with intramolecular photostabilization

    NARCIS (Netherlands)

    van der Velde, Jasper H M; Oelerich, Jens; Huang, Jingyi; Smit, Jochem H; Aminian Jazi, Atieh; Galiani, Silvia; Kolmakov, Kirill; Guoridis, Giorgos; Eggeling, Christian; Herrmann, Andreas; Roelfes, Gerard; Cordes, Thorben

    2016-01-01

    Intramolecular photostabilization via triple-state quenching was recently revived as a tool to impart synthetic organic fluorophores with 'self-healing' properties. To date, utilization of such fluorophore derivatives is rare due to their elaborate multi-step synthesis. Here we present a general

  7. Synthesis and photophysical properties of a series of cyclopenta[b]naphthalene solvatochromic fluorophores.

    Science.gov (United States)

    Benedetti, Erica; Kocsis, Laura S; Brummond, Kay M

    2012-08-01

    The synthesis and photophysical properties of a series of naphthalene-containing solvatochromic fluorophores are described within. These novel fluorophores are prepared using a microwave-assisted dehydrogenative Diels-Alder reaction of styrene, followed by a palladium-catalyzed cross coupling reaction to install an electron donating amine group. The new fluorophores are structurally related to Prodan. Photophysical properties of the new fluorophores were studied and intriguing solvatochromic behavior was observed. For most of these fluorophores, high quantum yields (60-99%) were observed in methylene chloride in addition to large Stokes shifts (95-226 nm) in this same solvent. As the solvent polarity increased, so did the observed Stokes shift with one derivative displaying a Stokes shift of ~300 nm in ethanol. All fluorophore emission maxima, and nearly all absorption maxima were significantly red-shifted when compared to Prodan. Shifting the absorption and emission maxima of a fluorophore into the visible region increases its utility in biological applications. Moreover, the cyclopentane portion of the fluorophore structure provides an attachment point for biomolecules that will minimize disruptions of the photophysical properties.

  8. Mapping absolute tissue endogenous fluorophore concentrations with chemometric wide-field fluorescence microscopy

    Science.gov (United States)

    Xu, Zhang; Reilley, Michael; Li, Run; Xu, Min

    2017-06-01

    We report chemometric wide-field fluorescence microscopy for imaging the spatial distribution and concentration of endogenous fluorophores in thin tissue sections. Nonnegative factorization aided by spatial diversity is used to learn both the spectral signature and the spatial distribution of endogenous fluorophores from microscopic fluorescence color images obtained under broadband excitation and detection. The absolute concentration map of individual fluorophores is derived by comparing the fluorescence from "pure" fluorophores under the identical imaging condition following the identification of the fluorescence species by its spectral signature. This method is then demonstrated by characterizing the concentration map of endogenous fluorophores (including tryptophan, elastin, nicotinamide adenine dinucleotide, and flavin adenine dinucleotide) for lung tissue specimens. The absolute concentrations of these fluorophores are all found to decrease significantly from normal, perilesional, to cancerous (squamous cell carcinoma) tissue. Discriminating tissue types using the absolute fluorophore concentration is found to be significantly more accurate than that achievable with the relative fluorescence strength. Quantification of fluorophores in terms of the absolute concentration map is also advantageous in eliminating the uncertainties due to system responses or measurement details, yielding more biologically relevant data, and simplifying the assessment of competing imaging approaches.

  9. 40 CFR 721.10163 - Chloro fluoro alkane (generic).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Chloro fluoro alkane (generic). 721.10163 Section 721.10163 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC...)(2) of this section. (2) The significant new uses are: (i) Industrial, commercial, and consumer...

  10. Labeling proteins inside living cells using external fluorophores for microscopy.

    Science.gov (United States)

    Teng, Kai Wen; Ishitsuka, Yuji; Ren, Pin; Youn, Yeoan; Deng, Xiang; Ge, Pinghua; Lee, Sang Hak; Belmont, Andrew S; Selvin, Paul R

    2016-12-09

    Site-specific fluorescent labeling of proteins inside live mammalian cells has been achieved by employing Streptolysin O, a bacterial enzyme which forms temporary pores in the membrane and allows delivery of virtually any fluorescent probes, ranging from labeled IgG's to small ligands, with high efficiency (>85% of cells). The whole process, including recovery, takes 30 min, and the cell is ready to be imaged immediately. A variety of cell viability tests were performed after treatment with SLO to ensure that the cells have intact membranes, are able to divide, respond normally to signaling molecules, and maintains healthy organelle morphology. When combined with Oxyrase, a cell-friendly photostabilizer, a ~20x improvement in fluorescence photostability is achieved. By adding in glutathione, fluorophores are made to blink, enabling super-resolution fluorescence with 20-30 nm resolution over a long time (~30 min) under continuous illumination. Example applications in conventional and super-resolution imaging of native and transfected cells include p65 signal transduction activation, single molecule tracking of kinesin, and specific labeling of a series of nuclear and cytoplasmic protein complexes.

  11. A G-quadruplex-containing RNA activates fluorescence in a GFP-like fluorophore

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Hao; Suslov, Nikolai B.; Li, Nan-Sheng; Shelke, Sandip A.; Evans, Molly E.; Koldobskaya, Yelena; Rice, Phoebe A.; Piccirilli, Joseph A. [UC

    2014-08-21

    Spinach is an in vitro–selected RNA aptamer that binds a GFP-like ligand and activates its green fluorescence. Spinach is thus an RNA analog of GFP and has potentially widespread applications for in vivo labeling and imaging. We used antibody-assisted crystallography to determine the structures of Spinach both with and without bound fluorophore at 2.2-Å and 2.4-Å resolution, respectively. Spinach RNA has an elongated structure containing two helical domains separated by an internal bulge that folds into a G-quadruplex motif of unusual topology. The G-quadruplex motif and adjacent nucleotides comprise a partially preformed binding site for the fluorophore. The fluorophore binds in a planar conformation and makes extensive aromatic stacking and hydrogen bond interactions with the RNA. Our findings provide a foundation for structure-based engineering of new fluorophore-binding RNA aptamers.

  12. Radiation decomposition of alcohols and chloro phenols in micellar systems

    International Nuclear Information System (INIS)

    Moreno A, J.

    1998-01-01

    The effect of surfactants on the radiation decomposition yield of alcohols and chloro phenols has been studied with gamma doses of 2, 3, and 5 KGy. These compounds were used as typical pollutants in waste water, and the effect of the water solubility, chemical structure, and the nature of the surfactant, anionic or cationic, was studied. The results show that anionic surfactant like sodium dodecylsulfate (SDS), improve the radiation decomposition yield of ortho-chloro phenol, while cationic surfactant like cetyl trimethylammonium chloride (CTAC), improve the radiation decomposition yield of butyl alcohol. A similar behavior is expected for those alcohols with water solubility close to the studied ones. Surfactant concentrations below critical micellar concentration (CMC), inhibited radiation decomposition for both types of alcohols. However radiation decomposition yield increased when surfactant concentrations were bigger than the CMC. Aromatic alcohols decomposition was more marked than for linear alcohols decomposition. On a mixture of alcohols and chloro phenols in aqueous solution the radiation decomposition yield decreased with increasing surfactant concentration. Nevertheless, there were competitive reactions between the alcohols, surfactants dimers, hydroxyl radical and other reactive species formed on water radiolysis, producing a catalytic positive effect in the decomposition of alcohols. Chemical structure and the number of carbons were not important factors in the radiation decomposition. When an alcohol like ortho-chloro phenol contained an additional chlorine atom, the decomposition of this compound was almost constant. In conclusion the micellar effect depend on both, the nature of the surfactant (anionic or cationic) and the chemical structure of the alcohols. The results of this study are useful for wastewater treatment plants based on the oxidant effect of the hydroxyl radical, like in advanced oxidation processes, or in combined treatment such as

  13. Radiation initiated polymerisation of phenyl methacrylate

    International Nuclear Information System (INIS)

    Raghunath, S.; Rao, M.H.; Rao, K.N.

    1983-01-01

    Radiation initiated polymerisation of phenyl methacrylate has been studied at various dose rates and temperature. Predominant chain transfer to the monomer was observed and ksub(tran)/Ksub(p) the chain transfer constant ratio was found to be 4 x 10 -2 .ksub(p)/ksub(tsup(1/2)) value determined by the kinetic data and the molecular weight data were 0.0821 and 0.0198, respectively. IR studies of polymer at low conversion showed the presence of terminal unsaturation which disappeared at saturation conversion, thus showing its participation in the formation of a three dimensional network. (author)

  14. Nondoped deep blue OLEDs based on Bis-(4-benzenesulfonyl-phenyl)-9-phenyl-9H-carbazoles

    International Nuclear Information System (INIS)

    Huang, Bin; Yin, Zhihui; Ban, Xinxin; Ma, Zhongming; Jiang, Wei; Tian, Wenwen; Yang, Min; Ye, Shanghui; Lin, Baoping; Sun, Yueming

    2016-01-01

    Two bipolar materials based on 9-phenylcarbazole and diphenyl sulfone for nondoped deep blue OLEDs, namely bis-(4-benzenesulfonyl-phenyl)-9-phenyl-9H-carbazoles, have been designed and synthesized by Suzuki coupling reactions. Their thermal, photophysical, and electrochemical properties have been systematically investigated. The nondoped devices using 3,6–bis–(4-benzenesulfonyl-phenyl)-9-phenyl-9H-carbazoles and 2,7-bis-(4-benzenesulfonyl-phenyl)-9-phenyl-9H-carbazoles as the emitters show deep blue emission color with peaks at 424 and 444 nm, and the Commission Internationale de l'Eclairage (CIE) coordinates of (0.177, 0.117) and (0.160, 0.117), respectively. Furthermore, these materials based devices have high color-purity with small width at half-maximum (FWHM) of 65 and 73 nm, respectively. The results provide a novel approach for the design of deep blue emitter for nondoped OLEDs.

  15. The lowest excited singlet state of isolated 1-phenyl-butadiene and 1-phenyl-hexatriene

    NARCIS (Netherlands)

    Kohler, B.E.; Shaler, T.A.; Buma, W.J.; Song, K.; Nuss, J.M.

    1992-01-01

    We report vibrationally resolved S0S1 excitation spectra and vibronic level decay times for the phenyl-substituted polyenes 1-phenylbutadiene and 1-phenylhexatriene seeded in supersonic He expansions. This information was obtained using one- and two-color resonance-enhanced multiphoton ionization

  16. Optical detection of two-color-fluorophore barcode for nanopore DNA sensing

    Science.gov (United States)

    Zhang, M.; Sychugov, I.; Schmidt, T.; Linnros, J.

    2015-06-01

    A simple schematic on parallel optical detection of two-fluorophore barcode for single-molecule nanopore sensing is presented. The chosen two fluorophores, ATTO-532 and DY-521-XL, emitting in well-separated spectrum range can be excited at the same wavelength. A beam splitter was employed to separate signals from the two fluorophores and guide them to the same CCD camera. Based on a conventional microscope, sources of background in the nanopore sensing system, including membranes, compounds in buffer solution, and a detection cell was characterized. By photoluminescence excitation measurements, it turned out that silicon membrane has a negligible photoluminescence under the examined excitation from 440 nm to 560 nm, in comparison with a silicon nitrite membrane. Further, background signals from the detection cell were suppressed. Brownian motion of 450 bps DNA labelled with single ATTO-532 or DY-521-XL was successfully recorded by our optical system.

  17. Undoped poly (phenyl sulfone) for radiation detection

    International Nuclear Information System (INIS)

    Nakamura, Hidehito; Shirakawa, Yoshiyuki; Sato, Nobuhiro; Kitamura, Hisashi; Takahashi, Sentaro

    2015-01-01

    Undoped aromatic ring polymers are potential scintillation materials. Here, we characterise poly (phenyl sulfone) (PPSU) for radiation detection. The amber-coloured transparent resin emits bluish-white fluorescence with 390-nm maximum. It has an excitation maximum of 340 nm, and has a density of 1.29 g/cm 3 . The effective refractive index based on its emission spectrum is 1.75. The light yield is almost equal to that of poly (ethylene terephthalate), which is a transparent resin. These results demonstrate that PPSU can be used as a component substrate in polymer blends for altering optical characteristics. - Highlights: • Poly (phenyl sulfone) (PPSU) has suitable characteristics as a scintillation material. • PPSU is an amber-coloured transparent resin that emits bluish white fluorescence with 390-nm maximum. • The 1.75 effective refractive index over the emission spectrum is relatively high. • The light yield is 0.95 times that of poly (ethylene terephthalate), which is a transparent resin. • PPSU can potentially alter optical characteristics in polymer blends

  18. Polymerization of N-(fluoro phenyl) maleimides

    International Nuclear Information System (INIS)

    Barrales-Rienda, J.M.; Ramos, J.G.; Chaves, M.S.

    1979-01-01

    Poly(N-aryl maleimide)s of characteristic structures have been synthesized and some of their physical properties studied. The polymerization of N-(fluoro phenyl) maleimides by free-radical initiation in bulk or in solution and by anionic catalyst have been studied to compare the characteristics of polymerization by γ-ray irradiation with that by free-radical initiation. The polymers were characterized by elemental analysis, intrinsic viscosity, spectroscopy (IR and NMR), programmed thermogravimetric analysis, and x-ray diffraction. Spectra of polymers prepared by radiation and anionic polymerization were nearly identical with those of polymers prepared by free-radical polymerization initiated by azobisisobutyronitrile in bulk or in solution and by the self-initiated thermal polymerization. A variety of reaction conditions were tried, but all attempts to change the molecular structure of the polymers were unsuccessful. Rates of thermal degradation for poly[N-(fluoro phenyl) maleimide]s have been analyzed by using a multiple-heating-rate procedure. Overall activation energy, order of reaction, and frequency factor have been evaluated. 6 figures, 8 tables

  19. Ammonium diamminesilver(I bis(5-chloro-2-hydroxybenzenesulfonate trihydrate

    Directory of Open Access Journals (Sweden)

    Zhao-Peng Deng

    2012-02-01

    Full Text Available The reaction of silver nitrate with 5-chloro-2-hydroxybenzenesulfonic acid in the presence of ammonia yielded the title salt, (NH4[Ag(NH32](C6H4ClO4S2·3H2O. The AgI ion shows linear coordination [N—Ag—N = 175.2 (1 °]. The ammonium and diamminesilver cations, the benzenesulfonate anion and the lattice water molecules interact through an intricate network of N—H...O and O—H...O hydrogen bonds to form a three-dimensional network.

  20. Dual-mode fluorophore-doped nickel nitrilotriacetic acid-modified silica nanoparticles combine histidine-tagged protein purification with site-specific fluorophore labeling.

    Science.gov (United States)

    Kim, Sung Hoon; Jeyakumar, M; Katzenellenbogen, John A

    2007-10-31

    We present the first example of a fluorophore-doped nickel chelate surface-modified silica nanoparticle that functions in a dual mode, combining histidine-tagged protein purification with site-specific fluorophore labeling. Tetramethylrhodamine (TMR)-doped silica nanoparticles, estimated to contain 700-900 TMRs per ca. 23 nm particle, were surface modified with nitrilotriacetic acid (NTA), producing TMR-SiO2-NTA-Ni2+. Silica-embedded TMR retains very high quantum yield, is resistant to quenching by buffer components, and is modestly quenched and only to a certain depth (ca. 2 nm) by surface-attached Ni2+. When exposed to a bacterial lysate containing estrogen receptor alpha ligand binding domain (ERalpha) as a minor component, these beads showed very high specificity binding, enabling protein purification in one step. The capacity and specificity of these beads for binding a his-tagged protein were characterized by electrophoresis, radiometric counting, and MALDI-TOF MS. ERalpha, bound to TMR-SiO2-NTA-Ni++ beads in a site-specific manner, exhibited good activity for ligand binding and for ligand-induced binding to coactivators in solution FRET experiments and protein microarray fluorometric and FRET assays. This dual-mode type TMR-SiO2-NTA-Ni2+ system represents a powerful combination of one-step histidine-tagged protein purification and site-specific labeling with multiple fluorophore species.

  1. beta-Chloro-L-alanine inhibition of the Escherichia coli alanine-valine transaminase.

    OpenAIRE

    Whalen, W A; Wang, M D; Berg, C M

    1985-01-01

    beta-Chloro-L-alanine, an amino acid analog which inhibits a number of enzymes, reversibly inhibited the Escherichia coli K-12 alanine-valine transaminase, transaminase C. This inhibition, along with the inhibition of transaminase B, accounted for the isoleucine-plus-valine requirement of E. coli in the presence of beta-chloro-L-alanine.

  2. Selective Activation of N,N'-Diacyl Rhodamine Pro-fluorophores Paired with Releasing Enzyme, Porcine Liver Esterase (PLE).

    Science.gov (United States)

    Abney, Kristopher K; Ramos-Hunter, Susan J; Romaine, Ian M; Godwin, J Shawn; Sulikowski, Gary A; Weaver, Charles David

    2018-04-21

    This study reports the synthesis and testing of a family of rhodamine pro-fluorophores and an enzyme capable of converting pro-fluorophores to Rhodamine 110. We prepared a library of simple N,N'-diacyl rhodamines and investigated Porcine Liver Esterase (PLE) as an enzyme to activate rhodamine-based pro-fluorophores. A PLE-expressing cell line generated an increase in fluorescence rapidly upon pro-fluorophore addition demonstrating the rhodamine pro-fluorophores are readily taken up and fluorescent upon PLE-mediated release. Rhodamine pro-fluorophore amides trifluoroacetamide (TFAm) and proponamide (PAm) appeared to be the best substrates using a cell-based assay using PLE expressing HEK293. Our pro-fluorophore series showed diffusion into live cells and resisted endogenous hydrolysis. The use of our engineered cell line containing the exogenous enzyme PLE demonstrated the rigorousness of amide masking when compared to cells not containing PLE. This simple and selective pro-fluorophore rhodamine pair with PLE offers the potential to be used in vitro and in vivo fluorescence based assays. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Development of Fluorophore-Labeled Thailanstatin Antibody-Drug Conjugates for Cellular Trafficking Studies.

    Science.gov (United States)

    Kulkarni, Chethana; Finley, James E; Bessire, Andrew J; Zhong, Xiaotian; Musto, Sylvia; Graziani, Edmund I

    2017-04-19

    As the antibody-drug conjugate (ADC) field grows increasingly important for cancer treatment, it is vital for researchers to establish a firm understanding of how ADCs function at the molecular level. To gain insight into ADC uptake, trafficking, and catabolism-processes that are critical to ADC efficacy and toxicity-imaging studies have been performed with fluorophore-labeled conjugates. However, such labels may alter the properties and behavior of the ADC under investigation. As an alternative approach, we present here the development of a "clickable" ADC bearing an azide-functionalized linker-payload (LP) poised for "click" reaction with alkyne fluorophores; the azide group represents a significantly smaller structural perturbation to the LP than most fluorophores. Notably, the clickable ADC shows excellent potency in target-expressing cells, whereas the fluorophore-labeled product ADC suffers from a significant loss of activity, underscoring the impact of the label itself on the payload. Live-cell confocal microscopy reveals robust uptake of the clickable ADC, which reacts selectively in situ with a derivatized fluorescent label. Time-course trafficking studies show greater and more rapid net internalization of the ADCs than the parent antibody. More generally, the application of chemical biology tools to the study of ADCs should improve our understanding of how ADCs are processed in biological systems.

  4. Investigation of common fluorophores for the detection of nitrated explosives by fluorescence quenching

    International Nuclear Information System (INIS)

    Meaney, Melissa S.; McGuffin, Victoria L.

    2008-01-01

    Previous studies have indicated that nitrated explosives may be detected by fluorescence quenching of pyrene and related compounds. The use of pyrene, however, invokes numerous health and waste disposal hazards. In the present study, ten safer fluorophores are identified for quenching detection of target nitrated compounds. Initially, Stern-Volmer constants are measured for each fluorophore with nitrobenzene and 4-nitrotoluene to determine the sensitivity of the quenching interaction. For quenching constants greater than 50 M -1 , sensitivity and selectivity are investigated further using an extended set of target quenchers. Nitromethane, nitrobenzene, 4-nitrotoluene, and 2,6-dinitrotoluene are chosen to represent nitrated explosives and their degradation products; aniline, benzoic acid, and phenol are chosen to represent potential interfering compounds. Among the fluorophores investigated, purpurin, malachite green, and phenol red demonstrate the greatest sensitivity and selectivity for nitrated compounds. Correlation of the quenching rate constants for these fluorophores to Rehm-Weller theory suggests an electron-transfer quenching mechanism. As a result of the large quenching constants, purpurin, malachite green, and phenol red are the most promising for future detection of nitrated explosives via fluorescence quenching

  5. Exogenous near-infrared fluorophores and their applications in cancer diagnosis: biological and clinical perspectives.

    Science.gov (United States)

    Zhang, Hua; Uselman, Ryan R; Yee, Douglas

    2011-05-01

    Near-infrared fluorescent (NIRF) imaging is a rapidly growing research field which has the potential to be an important imaging modality in cancer diagnosis. Various exogenous NIR fluorophores have been developed for the technique, including small molecule fluorophores and nanoparticles. NIRF imaging has been used in animal models for the detection of cancer overthe last twenty years and has in recent years been used in human clinical trials. This article describes the types and characteristics of exogenous fluorophores available for in vivo fluorescent cancer imaging. The article also discusses the progression of NIRF cancer imaging over recent years and its future challenges, from both a biological and clinical perspective. in The review also looks at its application for lymph node mapping, tumor targeting and characterization, and tumor margin definition for surgical guidance. NIRF imaging is not in routine clinical cancer practice; yet, the authors predict that techniques using NIR fluorophores for tumor margin definition and lymph node mapping will enter clinical practice in the near future. The authors also anticipate that NIRF imaging research will lead to the development of flurophores with 'high brightness' that will overcome the limited penetration of this modality and be better suited for non invasive tumor targeting.

  6. Photoinduced electron transfer between anionic fluorophores and methyl viologen in homogeneous and microheterogeneous media

    Energy Technology Data Exchange (ETDEWEB)

    Burai, Tarak Nath; Panda, Debashis; Iyer, E Siva Subramaniam [Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400 076 (India); Datta, Anindya, E-mail: anindya@chem.iitb.ac.in [Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400 076 (India)

    2012-11-15

    The rate and extent of photoinduced electron transfer change significantly as a result of confinement in nanovolumes. Study of such processes is an active area of research in physical chemistry. The effect is most interesting when the molecules that participate in PET are charged. In the present article, the modulation of PET has been studied for two anionic fluorophores: Lucifer Yellow CH and chlorin p{sub 6} with Methylviologen dication. PET, manifested in the quenching of fluorescence of the fluorophores, has been modulated by incorporating the molecules in organized assemblies like micelles, reverse micelles and supramolecular hosts. The dynamics of the process has been monitored in the femtosecond to nanosecond timescale. The modulation of the electron transfer has been found to be occurring mainly due to the disruption of contact ion pairs formed between the fluorophores and the quencher. - Highlights: Black-Right-Pointing-Pointer Modulation of PET of biologically active fluorophores and Methyl viologen. Black-Right-Pointing-Pointer Static and Dynamic Quenching present. Black-Right-Pointing-Pointer PET enhanced upon encapsulation, studied through Fluorescence upconversion experiments. Black-Right-Pointing-Pointer Rotational anisotropy has significant contribution in quenching.

  7. Photoinduced electron transfer between anionic fluorophores and methyl viologen in homogeneous and microheterogeneous media

    International Nuclear Information System (INIS)

    Burai, Tarak Nath; Panda, Debashis; Iyer, E Siva Subramaniam; Datta, Anindya

    2012-01-01

    The rate and extent of photoinduced electron transfer change significantly as a result of confinement in nanovolumes. Study of such processes is an active area of research in physical chemistry. The effect is most interesting when the molecules that participate in PET are charged. In the present article, the modulation of PET has been studied for two anionic fluorophores: Lucifer Yellow CH and chlorin p 6 with Methylviologen dication. PET, manifested in the quenching of fluorescence of the fluorophores, has been modulated by incorporating the molecules in organized assemblies like micelles, reverse micelles and supramolecular hosts. The dynamics of the process has been monitored in the femtosecond to nanosecond timescale. The modulation of the electron transfer has been found to be occurring mainly due to the disruption of contact ion pairs formed between the fluorophores and the quencher. - Highlights: ► Modulation of PET of biologically active fluorophores and Methyl viologen. ► Static and Dynamic Quenching present. ► PET enhanced upon encapsulation, studied through Fluorescence upconversion experiments. ► Rotational anisotropy has significant contribution in quenching.

  8. Chloridobis{2-[(dimethylaminomethyl]phenyl}antimony(III

    Directory of Open Access Journals (Sweden)

    Marian Olaru

    2009-11-01

    Full Text Available In the title compound, [Sb(C9H12N2Cl], the Sb atom adopts a Ψ-trigonal-bipyramidal geometry. The two 2-[(dimethylaminomethyl]phenyl ligands are coordinated asymmetrically to the Sb atom. The carbon atoms of one of the ligands are disordered over sets of sites with equal occupancy, resulting in two conformational isomers in the crystal. The Sb—C and Sb—N distances in the ordered ligand are: 2.153 (4 and 3.326 (5 Å, respectively. The corresponding distances in the disordered ligand are: 2.103 (5/2.188 (5 and 2.454 (3 Å, respectively. The structure displays intramolecular C—H...Cl hydrogen bonding.

  9. Synthesis and characterization of new alkylating agents 2-amino-4-phenyl thiazole

    Energy Technology Data Exchange (ETDEWEB)

    Sotelo, E.; Mocelo, R.; Suarez, M.; Gonzalez, L. [Laboratorio de Sintesis Organica, Facultad de Quimica, Universidad de la Habana, La Habana (Cuba)

    1996-10-01

    Starting with 2-amino-4-phenyl thiazole (1), the preparation of two new nitrosoureas 1-(4-phenyl-2-thiazole)-3-(2-chloroethyl)-3-nitrosourea (3), 1-(5-bromo-4-phenyl-thiazolyl)-3-(2-chloroethyl)-3-nitrosourea (8) and the N,N-bis (2-chloroethyl)-4-phenyl-2-amino thiazole (9) is reported. 9 refs.

  10. The fluorescence behaviour of methyl and phenyl salicylate

    Science.gov (United States)

    Ford, D.; Thistlethwaite, P. J.; Woolfe, G. J.

    1980-01-01

    Fluorcsccnce lifetimes tor the 450 nm emission of methyl and phenyl salicylate in various solvents have been measured. Qucnching studics on the 340 nm fluorescence of these molecules point to the existence of three distinct ground state conformers.

  11. CCDC 940297: Experimental Crystal Structure Determination : (mu~2~-Chloro)-(mu~2~-2-(1-(1-(dimethylamino)ethyl)naphthalen-2-yl)-2-phenyl-1-(phenyl(phenylethynyl)phosphanyl)ethenyl)-chloro-(2-(1-(dimethylamino)ethyl)phenyl)-palladium-platinum dichloromethane solvate

    KAUST Repository

    Chen, Shuli

    2013-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  12. CCDC 940298: Experimental Crystal Structure Determination : (mu~2~-Chloro)-(mu~2~-2-(1-(1-(dimethylamino)ethyl)naphthalen-2-yl)-2-phenyl-1-(phenyl(phenylethynyl)phosphanyl)ethenyl)-chloro-(2-(1-(dimethylamino)ethyl)phenyl)-palladium-platinum acetone solvate

    KAUST Repository

    Chen, Shuli

    2013-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  13. Doping chloro boron subnaphthalocyanines and chloro boron subphthalocyanine in simple OLED architectures yields warm white incandescent-like emissions

    Science.gov (United States)

    Plint, Trevor G.; Lessard, Benoît H.; Bender, Timothy P.

    2018-01-01

    We have incorporated chloro boron subphthalocyanine (Cl-BsubPc) and chloro boron subnapthalocyanines (Cl-ClnBsubNcs) into organic light emitting diodes (OLEDs) that enabled an overall warm white emission with CIE coordinates close to that of a 60 W incandescent lightbulb. More specifically, we have shown that Cl-BsubPc and Cl-ClnBsubNcs can be used as dopant emitters in a simple host-dopant architecture, and we have compared the use of NPB and Alq3 as potential hosts for these materials. When doped into Alq3, Cl-BsubPc shows a strong orange emission, and Cl-ClnBsubNcs shows a moderately strong red emission. We have further demonstrated that Cl-BsubPc and Cl-ClnBsubNcs can be co-doped into the same layer giving combined orange and red emission peaks. A "cascade" energy transfer mechanism of sequential absorption and re-emission is proposed. Device performance characteristics such as luminance, current efficiency, photoluminescence efficiency, and external quantum efficiency are tabulated. Additionally, in view of ongoing research into white emitting OLEDs for indoor lighting purposes, the Colour Rendering Index (CRI), R9 values, and CIE co-ordinates for these devices are also discussed. We conclude from this study that the BsubNc chromophore has potential application as a red dopant in OLEDs including for indoor lighting. Additionally, given the scope for axial and peripheral derivatization of the BsubNc motif, we believe that this chromophore has many unexplored molecular design handles that will affect its ultimate performance and application in OLEDs and other opto-electronic devices.

  14. 5-Chloro-2-(2'-((dimethylamino)methyl)-4'-iodophenylthio)benzenamine: a new serotonin transporter ligand

    International Nuclear Information System (INIS)

    Oya, Shunichi; Choi, Seok-Rye; Kung, Mei-Ping; Kung, Hank F.

    2007-01-01

    Two novel ligands with 4' substitution on the Phenyl Ring B of biphenylthiol, 5-chloro-2-(2'-((dimethylamino)methyl)-4'-iodophenylthio)benzenamine (7) and 2-(2'-((dimethylamino)methyl)-4'-methoxyphenylthio)-5-iodobenzenamine (8), were prepared and tested as potential serotonin transporter (SERT) imaging agents. The new ligands displayed extremely high binding affinities to SERT (K i =0.22±0.09 and 0.11±0.04 nM, respectively), with very low binding affinities to dopamine and norepinephrine transporters (K i >1000 nM). The corresponding [ 125 I]7 and [ 125 I]8 were successfully prepared from tri-n-butyltin derivatives. They showed good brain uptakes and prolonged retention after intravenous injection in rats (brain uptake was 1.77% and 0.98% dose/g for [ 125 I]7, and 0.92% and 0.29% dose/g for [ 125 I]8, at 2 and 120 min, respectively). Significantly, [ 125 I]7 showed excellent uptake and prolonged retention in the hypothalamus, where SERT concentration was highest. The hypothalamus/cerebellum (HY/CB) ratios (target/background ratios) were 4.24, 7.10, 8.24 and 12.6 at 2, 4, 6 and 12 h, respectively. The HY/CB ratios for [ 125 I]8 were 3.97, 5.57 and 5.06 at 1, 2 and 4 h, respectively. Adding the 4'-iodo group to the Phenyl Ring B of Compound (7) appeared to reduce the rate of clearance from the brain, and kinetics favored uptake and retention in the hypothalamus. The localization of [ 125 I]7 in the hypothalamus region in the rat brain could be blocked by pretreatment with (+)McN5652, escitalopram and ADAM (2), which are all selective SERT ligands (at 2 mg/kg iv, 5 min pretreatment). Ex vivo autoradiograms of rat brain sections (at 4 h after intravenous injection of [ 125 I]7) showed intense labeling in regions of the brain known to have high SERT density. The excellent selective uptake and retention in the hypothalamus region suggest that [ 123 I]7 is a potential lead compound for developing new imaging agents targeting SERT-binding sites with single

  15. 5-Chloro-2-(2'-((dimethylamino)methyl)-4'-iodophenylthio)benzenamine: a new serotonin transporter ligand

    Energy Technology Data Exchange (ETDEWEB)

    Oya, Shunichi [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Choi, Seok-Rye [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Kung, Mei-Ping [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Kung, Hank F. [Department of Radiology, University of Pennsylvania, Philadelphia, PA 19104 (United States); Department of Pharmacology, University of Pennsylvania, Philadelphia, PA 19104 (United States)

    2007-02-15

    Two novel ligands with 4' substitution on the Phenyl Ring B of biphenylthiol, 5-chloro-2-(2'-((dimethylamino)methyl)-4'-iodophenylthio)benzenamine (7) and 2-(2'-((dimethylamino)methyl)-4'-methoxyphenylthio)-5-iodobenzenamine (8), were prepared and tested as potential serotonin transporter (SERT) imaging agents. The new ligands displayed extremely high binding affinities to SERT (K {sub i}=0.22{+-}0.09 and 0.11{+-}0.04 nM, respectively), with very low binding affinities to dopamine and norepinephrine transporters (K {sub i}>1000 nM). The corresponding [{sup 125}I]7 and [{sup 125}I]8 were successfully prepared from tri-n-butyltin derivatives. They showed good brain uptakes and prolonged retention after intravenous injection in rats (brain uptake was 1.77% and 0.98% dose/g for [{sup 125}I]7, and 0.92% and 0.29% dose/g for [{sup 125}I]8, at 2 and 120 min, respectively). Significantly, [{sup 125}I]7 showed excellent uptake and prolonged retention in the hypothalamus, where SERT concentration was highest. The hypothalamus/cerebellum (HY/CB) ratios (target/background ratios) were 4.24, 7.10, 8.24 and 12.6 at 2, 4, 6 and 12 h, respectively. The HY/CB ratios for [{sup 125}I]8 were 3.97, 5.57 and 5.06 at 1, 2 and 4 h, respectively. Adding the 4'-iodo group to the Phenyl Ring B of Compound (7) appeared to reduce the rate of clearance from the brain, and kinetics favored uptake and retention in the hypothalamus. The localization of [{sup 125}I]7 in the hypothalamus region in the rat brain could be blocked by pretreatment with (+)McN5652, escitalopram and ADAM (2), which are all selective SERT ligands (at 2 mg/kg iv, 5 min pretreatment). Ex vivo autoradiograms of rat brain sections (at 4 h after intravenous injection of [{sup 125}I]7) showed intense labeling in regions of the brain known to have high SERT density. The excellent selective uptake and retention in the hypothalamus region suggest that [{sup 123}I]7 is a potential lead compound for

  16. A comparative study of three different synthesis routes for hydrophilic fluorophore-doped silica nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Shahabi, Shakiba [University of Bremen, Advanced Ceramics (Germany); Treccani, Laura, E-mail: treccani@petroceramics.com [Petroceramics S.p.A., Kilometro Rosso Science Park (Italy); Rezwan, Kurosch [University of Bremen, Advanced Ceramics (Germany)

    2016-01-15

    The synthesis of fluorophore-doped silica nanoparticles (FDS NPs) with two conventional approaches, Stöber and microemulsion, as well as a novel amino acid-catalyzed seeds regrowth technique (ACSRT) is presented. The efficiency of each applied synthesis route toward incorporation of selected hydrophilic fluorophores, including rhodamine B isothiocyanate and fluorescein isothiocyanate, without and with an amine-containing crosslinker, into silica matrix was systematically studied. Our results clearly highlight the advantages of ACSRT to obtain FDS NPs with a remarkable encapsulation efficiency, high quantum yield, and enhanced stability against bleaching and dye leaking due to efficient embedding of the dyes inside silica network even without the amine-containing silane reagent. Moreover, evaluation of photostability of FDNPs internalized in human bone cells demonstrates the merits of ACSRT.

  17. Proton Induced Modulation of ICT and PET Processes in an Imidazo-phenanthroline Based BODIPY Fluorophores.

    Science.gov (United States)

    Thakare, Shrikant S; Chakraborty, Goutam; Kothavale, Shantaram; Mula, Soumyaditya; Ray, Alok K; Sekar, Nagaiyan

    2017-11-01

    BODIPY fluorophores linked with an imidazo-phenanthroline donor at α and β positions have been synthesized. Intriguing intramolecular charge transfer phenomenon is observed in both the dyes which has been extensively investigated using UV-vis absorption, steady-state and time-resolved fluorescence measurements. H-bonding and intrinsic polarity of the solvents has modulated the absorption and emission bands of these fluorophores strongly causing significant increase in the Stokes shifts. In spite of having difference only in terms of the position of donor subunit, the photophysics of these dyes are not only significantly different from each other, but contradictory too. Interestingly, acidochromic studies revealed the shuttling mechanism between ICT and PET processes for BDP 2. Quantum chemical calculations have been employed further to support experimental findings. DFT and TD-DFT method of analysis have been used to optimize ground and excited state geometries of the synthesized dyes.

  18. Investigation of photobleaching and saturation of single molecules by fluorophore recrossing events

    Energy Technology Data Exchange (ETDEWEB)

    Burrows, Sean M.; Reif, Randall D. [Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061 (United States); Pappas, Dimitri [Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061 (United States)], E-mail: d.pappas@ttu.edu

    2007-08-15

    A method for investigation of photobleaching and saturation of single molecules by fluorophore recrossing events in a laser beam is described. The diffraction-limited probe volumes encountered in single-molecule detection (SMD) produce high excitation irradiance, which can decrease available signal. The single molecules of several dyes were detected and the data was used to extract interpeak times above a defined threshold value. The interpeak times revealed the number of fluorophore recrossing events. The number of molecules detected that were within 2 ms of each other represented a molecular recrossing for this work. Calcein, fluorescein and R-phycoerythrin were analyzed and the saturation irradiance and photobleaching effects were determined as a function of irradiance. This approach is simple and it serves as a method of optimizing experimental conditions for single-molecule detection.

  19. Graphene oxide from silk cocoon: a novel magnetic fluorophore for multi-photon imaging

    OpenAIRE

    Roy, Manas; Kusurkar, Tejas Sanjeev; Maurya, Sandeep Kumar; Meena, Sunil Kumar; Singh, Sushil Kumar; Sethy, Niroj; Bhargava, Kalpana; Sharma, Raj Kishore; Goswami, Debabrata; Sarkar, Sabyasachi; Das, Mainak

    2013-01-01

    In this work, we synthesized graphene oxide from silk cocoon embarking its new dimension as a magnetic fluorophore when compared with its present technical status, which at best is for extracting silk as a biomaterial for tissue engineering applications. We produced graphene oxide by pyrolysing the silk cocoon in an inert atmosphere. The collected raw carbon is oxidized by nitric acid that readily produces multilayer graphene oxide with nano carbon particulates. Structural properties of the g...

  20. Crosslines, fluorophores in the AGE-related cross-linked proteins.

    Science.gov (United States)

    Ienaga, K; Nakamura, K; Hochi, T; Nakazawa, Y; Fukunaga, Y; Kakita, H; Nakano, K

    1995-01-01

    We can summarize our results as follows: (1) A pair of fluorescent crosslines were isolated from the Maillard reaction mixture; (2) AGE-proteins contained crossline-like structures, and (3) crossline-like immunoreactivities were accumulated in renal tissues of diabetic rats. From these results we concluded that fluorophores in AGE proteins have crossline-like structures and we had the first indication that XLs could be markers for renal disorders.

  1. Fluorophore-conjugated iron oxide nanoparticle labeling and analysis of engrafting human hematopoietic stem cells

    DEFF Research Database (Denmark)

    Maxwell, Dustin J; Bonde, Jesper; Hess, David A

    2008-01-01

    culture conditions to maintain viability without inducing terminal differentiation. In the current study, fluorescent molecules were covalently linked to dextran-coated iron oxide nanoparticles (Feridex) to characterize human HSC labeling to monitor the engraftment process. Conjugating fluorophores...... to the dextran coat for fluorescence-activated cell sorting purification eliminated spurious signals from nonsequestered nanoparticle contaminants. A short-term defined incubation strategy was developed that allowed efficient labeling of both quiescent and cycling HSC, with no discernable toxicity in vitro...

  2. Synthesis and Some Reactions of 3-Chloro-2-(cyanomethylene-1,2-dihydroquinoxalines

    Directory of Open Access Journals (Sweden)

    Wolfgang Pfleiderer

    2004-03-01

    Full Text Available 2,3-Dichloroquinoxaline and some of its derivatives have been reacted with malononitrile and ethyl cyanoacetate to yield a variety of 3-chloro-2-(cyanomethylene- 1,2-dihydroquinoxaline derivatives. The reaction of 3-chloro-2-(dicyanomethylene-1,2- dihydroquinoxaline (2e with pyridine and its methyl derivatives led to the zwitterionic structures 6a-6c. The structures of the newly synthesized compounds were assigned by spectroscopic data and elemental analyses.

  3. Reversible addition-fragmentation chain transfer polymerization of 2-chloro-1,3-butadiene

    OpenAIRE

    Pullan, Nikki; Liu, Max; Topham, Paul D.

    2013-01-01

    Controlled polymerization of 2-chloro-1,3-butadiene using reversible addition–fragmentation chain transfer (RAFT) polymerization has been demonstrated for the first time. 2-Chloro-1,3-butadiene, more commonly known as chloroprene, has significant industrial relevance as a crosslinked rubber, with uses ranging from adhesives to integral automotive components. However, problems surrounding the inherent toxicity of the lifecycle of the thiourea-vulcanized rubber have led to the need for control ...

  4. Circumvention of fluorophore photobleaching in fluorescence fluctuation experiments: a beam scanning approach.

    Science.gov (United States)

    Satsoura, Dmitri; Leber, Brian; Andrews, David W; Fradin, Cécile

    2007-04-23

    Photobleaching is a fluorophore-damaging process that commonly afflicts single-molecule fluorescence studies. It becomes an especially severe problem in fluorescence fluctuation experiments when studying slowly diffusing particles. One way to circumvent this problem is to use beam scanning to decrease the residence time of the fluorophores in the excitation volume. We report a systematic study of the effects of circular beam scanning on the photobleaching of fluorescent particles as observed in single-photon excitation fluorescence fluctuation experiments. We start by deriving a simple expression relating the average detected fluorescence to the photobleaching cross section of the fluorophores. We then perform numerical calculations of the spatial distribution of fluorescent particles in order to understand under which conditions beam scanning can prevent the formation of a photobleaching hole. To support these predictions, we show experimental results obtained for large unilamellar vesicles containing a small amount of the fluorescent lipophilic tracer DiD. We establish the required scanning radius and frequency range in order to obtain sufficient reduction of the photobleaching effect for that system. From the detected increase in fluorescence upon increase in scanning speed, we estimate the photobleaching cross section of DiD.

  5. Single-step generation of fluorophore-encapsulated gold nanoparticle core-shell materials

    International Nuclear Information System (INIS)

    Sardar, R; Shem, P M; Pecchia-Bekkum, C; Bjorge, N S; Shumaker-Parry, J S

    2010-01-01

    We report a simple route to produce fluorophore-encapsulated gold nanoparticles (AuNPs) in a single step under aqueous conditions using the fluorophore 1-pyrenemethylamine (PMA). Different amounts of PMA were used and the resulting core-shell gold nanoparticles were analyzed using UV-visible absorption spectroscopy, fluorescence spectroscopy, and transmission and scanning electron microscopy. Electron microscopy analysis shows nanoparticles consisting of a gold nanoparticle core which is encapsulated with a lower contrast shell. In the UV-visible spectra, we observed a significant red shift (37 nm) of the localized surface plasmon resonance (LSPR) absorption maximum (λ max ) compared to citrate-stabilized AuNPs of a similar size. We attribute the prominent LSPR wavelength shift for PMA-AuNP conjugates to the increase in the local dielectric environment near the gold nanoparticles due to the shell formation. This simple, aqueous-based synthesis is a new approach to the production of fluorophore-encapsulated AuNPs that could be applicable in biological sensing systems and photonic device fabrication.

  6. Quantification and characterization of enzymatically produced hyaluronan with fluorophore-assisted carbohydrate electrophoresis.

    Science.gov (United States)

    Kooy, Floor K; Ma, Muyuan; Beeftink, Hendrik H; Eggink, Gerrit; Tramper, Johannes; Boeriu, Carmen G

    2009-01-15

    Hyaluronan (HA) is a polysaccharide with high-potential medical applications, depending on the chain length and the chain length distribution. Special interest goes to homogeneous HA oligosaccharides, which can be enzymatically produced using Pasteurella multocida hyaluronan synthase (PmHAS). We have developed a sensitive, simple, and fast method, based on fluorophore-assisted carbohydrate electrophoresis (FACE), for characterization and quantification of polymerization products. A chromatographic pure fluorescent template was synthesized from HA tetrasaccharide (HA4) and 2-aminobenzoic acid. HA4-fluor and HA4 were used as template for PmHAS-mediated polymerization of nucleotide sugars. All products, fluorescent and nonfluorescent, were analyzed with gel electrophoresis and quantified using lane densitometry. Comparison of HA4- and HA4-fluor-derived polymers showed that the fluorophore did not negatively influence the PmHAS-mediated polymerization. Only even-numbered oligosaccharide products were observed using HA4-fluor or HA4 as template. The fluorophore intensity was linearly related to its concentration, and the limit of detection was determined to be 7.4pmol per product band. With this assay, we can now differentiate oligosaccharides of size range DP2 (degree of polymerization 2) to approximately DP400, monitor the progress of polymerization reactions, and measure subtle differences in polymerization rate. Quantifying polymerization products enables us to study the influence of experimental conditions on HA synthesis.

  7. Photo-physical characterization of fluorophore Ru(bpy32+ for optical biosensing applications

    Directory of Open Access Journals (Sweden)

    E.L. Sciuto

    2015-12-01

    Full Text Available We studied absorption, emission and lifetime of the coordination compound tris(2,2′-bipyridylruthenium(II fluorophore (Ru(bpy32+ both dissolved in water solutions and dried. Lifetime measurements were carried out using a new detector, the Silicon Photomultiplier (SiPM, which is more sensitive and physically much smaller than conventional optical detectors, such as imager and scanner. Through these analyses and a morphological characterization with transmission electron microscopy, revealed its usability for sensor applications, in particular, as dye in optical DNA-chip technology, a viable alternative to the conventional CY5 fluorophore. The use of Ru(bpy32+ would solve some of the typical disadvantages related to Cy5’s application, such as self-absorption of fluorescence and photobleaching. In addition, the Ru(bpy32+ longer lifetime may play a key role in the definition of new optical DNA-chip. Keywords: Tris(2,2′-bipyridylruthenium(II, Fluorophore, Spectroscopy, Lifetime measurements, SiPM, TEM

  8. Choice of Illumination System & Fluorophore for Multiplex Immunofluorescence on FFPE Tissue Sections.

    Directory of Open Access Journals (Sweden)

    Sandrine Prost

    Full Text Available The recent availability of novel dyes and alternative light sources to facilitate complex tissue immunofluorescence studies such as multiplex labelling has not been matched by reports critically evaluating the considerations and relative benefits of these new tools, particularly in combination. Product information is often limited to wavelengths used for older fluorophores (FITC, TRITC & corresponding Alexa dyes family. Consequently, novel agents such as Quantum dots are not widely appreciated or used, despite highly favourable properties including extremely bright emission, stability and potentially reduced tissue autofluorescence at the excitation wavelength. Using spectral analysis, we report here a detailed critical appraisal and comparative evaluation of different light sources and fluorophores in multiplex immunofluorescence of clinical biopsy sections. The comparison includes mercury light, metal halide and 3 different LED-based systems, using 7 Qdots (525, 565, 585, 605, 625, 705, Cy3 and Cy5. We discuss the considerations relevant to achieving the best combination of light source and fluorophore for accurate multiplex fluorescence quantitation. We highlight practical limitations and confounders to quantitation with filter-based approaches.

  9. Quantum dots versus organic fluorophores in fluorescent deep-tissue imaging--merits and demerits.

    Science.gov (United States)

    Bakalova, Rumiana; Zhelev, Zhivko; Gadjeva, Veselina

    2008-12-01

    The use of fluorescence in deep-tissue imaging is rapidly expanding in last several years. The progress in fluorescent molecular probes and fluorescent imaging techniques gives an opportunity to detect single cells and even molecular targets in live organisms. The highly sensitive and high-speed fluorescent molecular sensors and detection devices allow the application of fluorescence in functional imaging. With the development of novel bright fluorophores based on nanotechnologies and 3D fluorescence scanners with high spatial and temporal resolution, the fluorescent imaging has a potential to become an alternative of the other non-invasive imaging techniques as magnetic resonance imaging, positron-emission tomography, X-ray, computing tomography. The fluorescent imaging has also a potential to give a real map of human anatomy and physiology. The current review outlines the advantages of fluorescent nanoparticles over conventional organic dyes in deep-tissue imaging in vivo and defines the major requirements to the "perfect fluorophore". The analysis proceeds from the basic principles of fluorescence and major characteristics of fluorophores, light-tissue interactions, and major limitations of fluorescent deep-tissue imaging. The article is addressed to a broad readership - from specialists in this field to university students.

  10. Photo-reorganization of 3-alkoxy-6-chloro-2-(benzo[b]thiophen-2-yl)-4H-chromen-4-ones: a green and convenient synthesis of angular pentacyclics.

    Science.gov (United States)

    Dalal, Aarti; Khanna, Radhika; Kumar, Parvin; Kamboj, Ramesh C

    2017-05-17

    Photo-reorganization of 3-alkoxy-6-chloro-2-(benzo[b]thiophen-2-yl)-4H-chromen-4-ones in methanol with Pyrex filtered UV-light from a medium pressure 125 W Hg-vapor lamp led to the formation of angular pentacyclic compounds (dihydro and aromatic products) along with some rearranged chromenones where the product(s) distribution depended upon the structure of 3-alkoxy groups (methoxy, ethoxy, allyloxy and benzyloxy). The phenyl moiety in the 3-benzyloxy group had a profound effect on the dihydro product(s) formation as the latter was in high yield when the alkoxy group was benzyloxy followed by allyloxy, ethoxy and methoxy groups. The present photochemical study represents a general method for the synthesis of some angular pentacyclic - benzothiophene fused xanthenone derivatives in a single step without using any specific and toxic reagent. The structures of the new organic scaffolds obtained were established by their spectral data (UV, IR and NMR).

  11. Palladium-Catalyzed ortho-Olefination of Phenyl Acetic and Phenyl Propylacetic Esters via C-H Bond Activation.

    Science.gov (United States)

    Hu, Jundie; Guan, Mingyu; Han, Jian; Huang, Zhi-Bin; Shi, Da-Qing; Zhao, Yingsheng

    2015-08-21

    A highly regioselective palladium-catalyzed ester-directed ortho-olefination of phenyl acetic and propionic esters with olefins via C-H bond activation has been developed. A wide variety of phenyl acetic and propionic esters were tolerated in this transformation, affording the corresponding olefinated aromatic compounds. The ortho-olefination of heterocyclic acetic and propionic esters also took place smoothly giving the products in good yields, thus proving the potential utility of this protocol in synthetic chemistry.

  12. Silica Sol-Gel Entrapment of the Enzyme Chloro peroxidase

    International Nuclear Information System (INIS)

    Le, T.; Chan, S.; Ebaid, B.; Sommerhalter, M.

    2015-01-01

    The enzyme chloro peroxidase (CPO) was immobilized in silica sol-gel beads prepared from tetramethoxysilane. The average pore diameter of the silica host structure (∼3 nm) was smaller than the globular CPO diameter (∼6 nm) and the enzyme remained entrapped after sol-gel maturation. The catalytic performance of the entrapped enzyme was assessed via the pyrogallol peroxidation reaction. Sol-gel beads loaded with 4 μg CPO per mL sol solution reached 9-12% relative activity compared to free CPO in solution. Enzyme kinetic analysis revealed a decrease in K_cat but no changes in K_M or K_I . Product release or enzyme damage might thus limit catalytic performance. Yet circular dichroism and visible absorption spectra of transparent CPO sol-gel sheets did not indicate enzyme damage. Activity decline due to methanol exposure was shown to be reversible in solution. To improve catalytic performance the sol-gel protocol was modified. The incorporation of 5, 20, or 40% methyltrimethoxysilane resulted in more brittle sol-gel beads but the catalytic performance increased to 14% relative to free CPO in solution. The use of more acidic casting buffers (ph 4.5 or 5.5 instead of 6.5) resulted in a more porous silica host reaching up to 18% relative activity

  13. Differentiation of ocular fundus fluorophores by fluorescence lifetime imaging using multiple excitation and emission wavelengths

    Science.gov (United States)

    Hammer, M.; Schweitzer, D.; Schenke, S.; Becker, W.; Bergmann, A.

    2006-10-01

    Ocular fundus autofluorescence imaging has been introduced into clinical diagnostics recently. It is in use for the observation of the age pigment lipofuscin, a precursor of age - related macular degeneration (AMD). But other fluorophores may be of interest too: The redox pair FAD - FADH II provides information on the retinal energy metabolism, advanced glycation end products (AGE) indicate protein glycation associated with pathologic processes in diabetes as well as AMD, and alterations in the fluorescence of collagen and elastin in connective tissue give us the opportunity to observe fibrosis by fluorescence imaging. This, however, needs techniques able to differentiate particular fluorophores despite limited permissible ocular exposure as well as excitation wavelength (limited by the transmission of the human ocular lens to >400 nm). We present an ophthalmic laser scanning system (SLO), equipped with picosecond laser diodes (FWHM 100 ps, 446 nm or 468 nm respectively) and time correlated single photon counting (TCSPC) in two emission bands (500 - 560 nm and 560 - 700 nm). The decays were fitted by a bi-exponential model. Fluorescence spectra were measured by a fluorescence spectrometer fluorolog. Upon excitation at 446 nm, the fluorescence of AGE, FAD, and lipofuscin were found to peak at 503 nm, 525 nm, and 600 nm respectively. Accordingly, the statistical distribution of the fluorescence decay times was found to depend on the different excitation wavelengths and emission bands used. The use of multiple excitation and emission wavelengths in conjunction with fluorescence lifetime imaging allows us to discriminate between intrinsic fluorophores of the ocular fundus. Taken together with our knowledge on the anatomical structure of the fundus, these findings suggest an association of the short, middle and long fluorescence decay time to the retinal pigment epithelium, the retina, and connective tissue respectively.

  14. Colloidal lenses allow high-temperature single-molecule imaging and improve fluorophore photostability

    Science.gov (United States)

    Schwartz, Jerrod J.; Stavrakis, Stavros; Quake, Stephen R.

    2010-02-01

    Although single-molecule fluorescence spectroscopy was first demonstrated at near-absolute zero temperatures (1.8 K), the field has since advanced to include room-temperature observations, largely owing to the use of objective lenses with high numerical aperture, brighter fluorophores and more sensitive detectors. This has opened the door for many chemical and biological systems to be studied at native temperatures at the single-molecule level both in vitro and in vivo. However, it is difficult to study systems and phenomena at temperatures above 37 °C, because the index-matching fluids used with high-numerical-aperture objective lenses can conduct heat from the sample to the lens, and sustained exposure to high temperatures can cause the lens to fail. Here, we report that TiO2 colloids with diameters of 2 µm and a high refractive index can act as lenses that are capable of single-molecule imaging at 70 °C when placed in immediate proximity to an emitting molecule. The optical system is completed by a low-numerical-aperture optic that can have a long working distance and an air interface, which allows the sample to be independently heated. Colloidal lenses were used for parallel imaging of surface-immobilized single fluorophores and for real-time single-molecule measurements of mesophilic and thermophilic enzymes at 70 °C. Fluorophores in close proximity to TiO2 also showed a 40% increase in photostability due to a reduction of the excited-state lifetime.

  15. In vivo determination of optical properties and fluorophore characteristics of non-melanoma skin cancer

    Science.gov (United States)

    Rajaram, Narasimhan; Kovacic, Dianne; Migden, Michael F.; Reichenberg, Jason S.; Nguyen, Tri H.; Tunnell, James W.

    2009-02-01

    Diffuse optical spectroscopy (DOS) and laser-induced fluorescence (LIF) techniques have widely been used as noninvasive tools for early cancer detection in several organs including the cervix, oral cavity and gastrointestinal tract. Using a combined DOS/LIF approach, one can simultaneously measure the morphology and biochemical composition of tissue and use these features to diagnose malignancy. We report for the first time to our knowledge both the optical properties and native fluorophore characteristics of non-melanoma skin cancer in the UV-visible range. We collected in vivo diffuse reflectance and intrinsic fluorescence measurements from 44 skin lesions on 37 patients. The skin sites were further categorized into three groups of non-melanoma skin cancer according to histopathology: 1) pre-cancerous actinic keratosis 2) malignant squamous cell carcinoma (SCC) and 3) basal cell carcinoma (BCC). We used a custom-built probe-based clinical system that collects both white light reflectance and laser-induced fluorescence in the wavelength range of 350-700 nm. We extracted the blood volume fraction, oxygen saturation, blood vessel size, tissue microarchitecture and melanin content from diffuse reflectance measurements. In addition, we determined the native fluorophore contributions of NADH, collagen and FAD from laser-induced fluorescence for all groups. The scattering from tissue decreased with progression from clinically normal to precancerous actinic keratosis to malignant SCC. A similar trend was observed for clinically normal skin and malignant BCC. Statistically significant differences were observed in the collagen contributions, which were lower in malignant SCC and BCC as compared to normal skin. Our data demonstrates that the mean optical properties and fluorophore contributions of normal, benign and malignant nonmelanoma cancers are significantly different from each other and can potentially be used as biomarkers for the early detection of skin cancer.

  16. Specific optical signalling of anions via intramolecular charge transfer pathway based on acridinedione fluorophore

    International Nuclear Information System (INIS)

    Thiagarajan, Viruthachalam; Ramamurthy, Perumal

    2007-01-01

    We present a simple but highly specific acridinedione fluorophore (ADD-1) that acts both as a fluorescent and colorimetric sensor for anions in acetonitrile. The specific optical signalling of ADD-1 is due to the formation of new distinct intramolecular charge transfer (ICT) emitting states in the presence of AcO - (490 nm), H 2 PO 4 - (440 nm), and F - (510 nm) over other anions. Presence of F - shows a colour change that is perceptible to the naked eye, from colourless to an intense fluorescent green due to the deprotonation of acridinedione ring amino hydrogen

  17. Efficient electroluminescence from a perylenediimide fluorophore obtained from a simple solution processed OLED

    International Nuclear Information System (INIS)

    Cespedes-Guirao, F J; Fernandez-Lazaro, F; Sastre-Santos, A; Garcia-Santamaria, S; Bolink, H J

    2009-01-01

    Simple solution processed organic light emitting diodes are used to screen the performance of two types of highly efficient, narrow band red emitting fluorescent perylenediimides (PDIs). PDIs substituted at the diimide positions seem to form aggregates in the thin film architecture as evidenced by the shifted electroluminescent spectrum. When substituted on the bay position and when used both as the emitting and the electron transporting specie, bright electroluminescence with a narrow width around 610 nm reaching 500 cd m -2 at moderate voltages was observed, demonstrating the usefulness of these fluorophores for OLED applications.

  18. Radioiodinated N-(2-aminoethyl)-2-chloro-4-iodobenzamide

    International Nuclear Information System (INIS)

    Ohmomo, Yoshiro; Murakami, Katsuhiko; Tanaka, Chiaki; Hirata, Masahiko; Magata, Yasuhiro; Yokoyama, Akira.

    1994-01-01

    In developing monoamine oxidase (MAO)-B specific radioligands, N-(2-aminoethyl)-2-chloro-4-[ 125 I]iodobenzamide ([ 125 I]FIBA) was conveniently synthesized from its tributylstannyl precursor by an iododestannylation reaction using sodium [ 125 I]iodide and hydrogen peroxide with high radiochemical yield. The method should be applicable for labeling with 123 I, a suitable radioisotope for in vivo imaging with single photon emission computed tomography (SPECT). In vitro binding studies using mouse brain mitochondrial preparations showed that the specific binding of [ 125 I]FIBA was saturable and of high affinity. Calculated values for K D and B max were 201 nM and 9.5 pmol/mg protein, respectively. The [ 125 I]FIBA binding was effectively prevented by MAO-B specific inhibitors (l-deprenyl, Ro 16-6491, FIBA) or substrate (β-phenethylamine). However, MAO-A specific inhibitor (clorgyline) and substrate (serotonin) had no significant effect. After an intravenous injection into mice, [ 125 I]FIBA showed high brain uptake (1.64% dose/g at 15-30 min post injection) and long retention (1.11% dose/g at 120 min post injection) in the brain. Good brain-to-blood radioactivity ratios of 2.19 and 2.41 at 60 and 120 min after injection, respectively, were obtained. The in vitro binding data and in vivo characteristics suggested that [ 125 I]FIBA is potentially useful as a probe for biological studies including specific labeling of MAO-B in vivo as well as in vitro. Moreover, the 123 I-labeled counterpart, [ 123 I]FIBA, might be valuable for non-invasive imaging and mapping of MAO-B in the living brain with SPECT. (author)

  19. Synthesis, Characterization and Antimicrobial Activity of Metal Chelates of 5-[4-Chloro phenyl(1, 3, 4thiadiazol-2-ylamino methylene]-8-hydroxy quinoline

    Directory of Open Access Journals (Sweden)

    Divyesh K. Patel

    2009-01-01

    Full Text Available 5-Chloromethyl-8-quinolinol was condensed stoichiometrically with 5-(4-chlorophenyl-(1,3,4 thiadiazol-2-ylamine in the presence of sodium bicarbonate. The resulting 5-[4-chlorophenyl-(1,3,4thiadiazol-2-ylamino methylene]-8-quinolinol (CTAQ was characterized by elemental analysis and spectral studies. The transition metal chelates viz. Cu2+, Ni2+, Co2+, Mn2+ and Zn2+ of CTAQ were prepared and characterized by metal-ligand (M:L ratio, IR and reflectance spectroscopies and magnetic properties. The antifungal activity of CTAQ and its metal chelates was screened against various fungi. The results show that all these samples are good antifungal agents.

  20. CCDC 879684: Experimental Crystal Structure Determination : chloro-(2,6-bis((bis(cyclopentyl)phosphino)oxy)-4-(ethoxycarbonyl)phenyl)-nickel(ii)

    KAUST Repository

    Chen, Tao

    2012-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  1. CCDC 879685: Experimental Crystal Structure Determination : Chloro-(3,5-di-t-butyl-2,6-bis((di-t-butylphosphino)oxy)phenyl)-nickel(ii)

    KAUST Repository

    Chen, Tao

    2012-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  2. CCDC 926491: Experimental Crystal Structure Determination : Chloro-(1,3-bis(2,6-bis(pentan-3-yl)phenyl)imidazol-2-ylidene)-gold

    KAUST Repository

    Collado, Alba

    2013-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  3. Synthesis and biological activities of 3-1-(3-(2-chloro-3,3,3-trifluoro-prop-1-enyl) 2,2-dimethylcyclopropanecarbonyl)-3substituted phenyl thiourea

    International Nuclear Information System (INIS)

    Sun, N.B.; Lei, C.; Jin, J.Z.; Zhang, J.F.

    2013-01-01

    Some thiourea compounds containing pyrethroids are synthesized. Their structures were confirmed by 1H-NMR, MS and elemental analysis. The bioassay results indicated that they showed moderate insecticidal and fungicidal activity. (author)

  4. CCDC 879684: Experimental Crystal Structure Determination : chloro-(2,6-bis((bis(cyclopentyl)phosphino)oxy)-4-(ethoxycarbonyl)phenyl)-nickel(ii)

    KAUST Repository

    Chen, Tao; Yang, Limin; LI, LIANG; Huang, Kuo-Wei

    2012-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from

  5. On the bioactive conformation of R(+)-8-chloro-2,3,4,5-tetrahydro-3-methyl-5-phenyl-1H-3-benzazepin-7-ol

    Science.gov (United States)

    Verdonk, M. L.; Voogd, K.; Kanters, J. A.; Kroon, J.; van Duijneveldt, F. B.

    1994-07-01

    A redetermination of the X-ray structure of the title compound is reported. In this structure a partially occupied position of a water molecule was found that was not observed in an earlier structure determination. This water molecule appears to have an important role in the crystal packing. Molecular mechanics calculations were performed on 12 conformations of the protonated title compound, complexed to a chloride anion. This anion represents the anionic binding site of the receptors at which the title compound exerts its biological activity. Crystal-structure statistics and ab initio calculations were used to generate starting geometries for the molecular mechanics calculations. It appears that the conformation that is assumed to be the active conformation for the D 1 receptor is the lowest-energy conformation. It is concluded that this conformation may, therefore, also be the active conformation for other receptors.

  6. Synthesis of some Heterocyclic Compounds Derived from 2-Chloro-N-p-Tolylacetamide

    Directory of Open Access Journals (Sweden)

    Hanan Gh Shaaban

    2017-02-01

    Full Text Available This research includes preparation of (2-chloro-N-p-tolylacetamide (1 from the reaction of (p-aminotoluene with chloro acetyl chloride. Compound (1 reacted with thiosemi carbazide and gave compound (2, and when compound (1 reacted with semicarbazide gave compound (3. While when compound (1 reacted with thiourea it produced compound (4. Compounds (2-4 when reacted with appropriate aromatic aldehydes or ketones produced Shiff bass (5-16, which in turn reacted with chloro acetyl chloride in the present of tri ethyl amine and dioxin gave β-lactam derivatives (14-22. The structures of these compounds were characterized from their melting points, FT-IR, and NMR.

  7. Graphene oxide from silk cocoon: a novel magnetic fluorophore for multi-photon imaging.

    Science.gov (United States)

    Roy, Manas; Kusurkar, Tejas Sanjeev; Maurya, Sandeep Kumar; Meena, Sunil Kumar; Singh, Sushil Kumar; Sethy, Niroj; Bhargava, Kalpana; Sharma, Raj Kishore; Goswami, Debabrata; Sarkar, Sabyasachi; Das, Mainak

    2014-02-01

    In this work, we synthesized graphene oxide from silk cocoon embarking its new dimension as a magnetic fluorophore when compared with its present technical status, which at best is for extracting silk as a biomaterial for tissue engineering applications. We produced graphene oxide by pyrolysing the silk cocoon in an inert atmosphere. The collected raw carbon is oxidized by nitric acid that readily produces multilayer graphene oxide with nano carbon particulates. Structural properties of the graphene oxide were analyzed using scanning electron microscopy, transmission electron microscopy, Fourier transform infra-red spectroscopy, and Raman spectroscopy. The oxidized sample shows remarkable fluorescence, multi-photon imaging and magnetic properties. On increasing the excitation wavelength, the fluorescence emission intensity of the graphene oxide also increases and found maximum emission at 380 nm excitation wavelength. On studying the two photon absorption (TPA) property of aqueous graphene oxide using Z-scan technique, we found significant TPA activity at near infrared wavelength. In addition, the graphene oxide shows ferromagnetic behavior at room temperature. The observed fluorescence and magnetic property were attributed to the defects caused in the graphene oxide structure by introducing oxygen containing hydrophilic groups during the oxidation process. Previously silk cocoon has been used extensively in deriving silk-based tissue engineering materials and as gas filter. Here we show a novel application of silk cocoon by synthesizing graphene oxide based magnetic-fluorophore for bio-imaging applications.

  8. Temporal and mechanistic tracking of cellular uptake dynamics with novel surface fluorophore-bound nanodiamonds.

    Science.gov (United States)

    Schrand, Amanda M; Lin, Jonathan B; Hens, Suzanne Ciftan; Hussain, Saber M

    2011-02-01

    Nanoparticles (NPs) offer promise for a multitude of biological applications including cellular probes at the bio-interface for targeted delivery of anticancer substances, Raman and fluorescent-based imaging and directed cell growth. Nanodiamonds (NDs), in particular, have several advantages compared to other carbon-based nanomaterials - including a rich surface chemistry useful for chemical conjugation, high biocompatibility with little reactive oxygen species (ROS) generation, physical and chemical stability that affords sterilization, high surface area to volume ratio, transparency and a high index of refraction. The visualization of ND internalization into cells is possible via photoluminescence, which is produced by direct dye conjugation or high energy irradiation that creates nitrogen vacancy centers. Here, we explore the kinetics and mechanisms involved in the intracellular uptake and localization of novel, highly-stable, fluorophore-conjugated NDs. Examination in a neuronal cell line (N2A) shows ND localization to early endosomes and lysosomes with eventual release into the cytoplasm. The addition of endocytosis and exocytosis inhibitors allows for diminished uptake and increased accumulation, respectively, which further corroborates cellular behavior in response to NDs. Ultimately, the ability of the NDs to travel throughout cellular compartments of varying pH without degradation of the surface-conjugated fluorophore or alteration of cell viability over extended periods of time is promising for their use in biomedical applications as stable, biocompatible, fluorescent probes.

  9. Energy down converting organic fluorophore functionalized mesoporous silica hybrids for monolith-coated light emitting diodes

    Directory of Open Access Journals (Sweden)

    Markus Börgardts

    2017-04-01

    Full Text Available The covalent attachment of organic fluorophores in mesoporous silica matrices for usage as energy down converting phosphors without employing inorganic transition or rare earth metals is reported in this article. Triethoxysilylpropyl-substituted derivatives of the blue emitting perylene, green emitting benzofurazane, and red emitting Nile red were synthesized and applied in the synthesis of mesoporous hybrid materials by postsynthetic grafting to commercially available MCM-41. These individually dye-functionalized hybrid materials are mixed in variable ratios to furnish a powder capable of emitting white light with CIE chromaticity coordinates of x = 0.33, y = 0.33 and an external quantum yield of 4.6% upon irradiation at 410 nm. Furthermore, as a proof of concept two different device setups of commercially available UV light emitting diodes, are coated with silica monoliths containing the three triethoxysilylpropyl-substituted fluorophore derivatives. These coatings are able to convert the emitted UV light into light with correlated color temperatures of very cold white (41100 K, 10700 K as well as a greenish white emission with correlated color temperatures of about 5500 K.

  10. A new multifunctional 1, 10-phenanthroline based fluorophore for anion and cation sensing

    Energy Technology Data Exchange (ETDEWEB)

    Alreja, Priya; Kaur, Navneet, E-mail: neet_chem@yahoo.co.in

    2015-12-15

    We report a new multi-ion responsive fluorophore 1 possessing an amide functionality featuring with 1, 10-phenanthroline unit with appropriately placed coordination sites for sensing Cu{sup 2+} and Zn{sup 2+} ions in 1:2 stoichiometry. Also, various functionalities of 1 organize to create an appropriate cavity to accommodate weakly basic and larger iodide ion generating 1:1 complex. The fluorescence intensity was greatly quenched on coordination of Cu{sup 2+}, Zn{sup 2+} and I{sup −} ions with appropriately placed multiple donor sites of 1 which was further supported by Density Functional Theory (DFT) computational studies. - Highlights: • A novel multifunctional 1, 10- Phenanthroline based fluorophore for sensing anion and cations. • First report on applicability of amides as multiple users for anion and cations. • Fluorescence quenching observed with Cu{sup 2+}, Zn{sup 2+} and I{sup -}. • Fluorescence titration experiments are well supported by DFT calculations.

  11. Synthesis of 1-(4-methylsulfone-phenyl)-5-(4-fluoro-phenyl)-5-[14C]-1,2,3- triazole and 1-(4-sulfonamide-phenyl)-5-(4-fluoro-phenyl)-5-[14C]-1,2,3- triazole as novel carbon-14 anticonvulsant

    International Nuclear Information System (INIS)

    Saemian, N.; Shirvani, G.; Matloubi, H.

    2006-01-01

    Two 1,2,3-triazole anticonvulsants, 1-(4-methylsulfone-phenyl)-5-(4-fluoro-phenyl)-5-[ 14 C]-1,2,3-triazole and 1-(4-sulfonamide-phenyl)-5-(4- fluoro-phenyl)-5-[ 14 C]-1,2,3-triazole, both labeled with carbon-14 in the 5-position were prepared from para-fluoro-benzonitrile-[cyano- 14 C]. (author)

  12. Design, Synthesis and Insecticidal Activities of Novel Phenyl Substituted Isoxazolecarboxamides

    Institute of Scientific and Technical Information of China (English)

    LIU Peng-fei; ZHANG Ji-feng; YAN Tao; XIONG Li-xia; LI Zheng-ming

    2012-01-01

    Thirteen novel phenyl substituted isoxazolecarboxamides were synthesized,and their structures were characterized by 1H NMR,elementary analysis and high-resolution mass spectrometry(HRMS) techniques.Their evaluated insecticidal activities against oriental armyworm(Mythimna separata) indicate that the phcnyl substituted isoxazolecarboxamides exhibited moderate insecticidal activities,among which compounds 9c and 9k showed comparatively higher activities.

  13. Excited State Spectra and Dynamics of Phenyl-Substituted Butadienes

    DEFF Research Database (Denmark)

    Wallace-Williams, Stacie E.; Schwartz, Benjamin J.; Møller, Søren

    1994-01-01

    indicate that phenyl torsional motion is not important to the excited-state dynamics and reveal alternative excited-state reaction pathways. The results demonstrate how molecular systems that are structually similar can exhibit different electronic properties and excited-state dynamics....

  14. Antiradiation compounds XV: condensations of carbon disulfide with amino, chloro, cyanomethyl, and sulfonamido heterocycles

    International Nuclear Information System (INIS)

    Foye, W.O.; Kauffman, J.M.; Lanzillo, J.J.; LaSala, E.F.

    1975-01-01

    Condensations of carbon disulfide were carried out with amino, chloro, and diamino heterocycles to give condensed ring thiazoline-2-thiones and imidazoline-2-thiones, with cyanomethyl heterocycles to give dithio acid derivatives, and with heterocyclic sulfonamides to give sulfonyldithiocarbamates. Of several examples tested, pyrido[3,2-d]thiazoline-2-thione, disodium 2-(5-chloro-2-thienyl)-3,3-dimercaptoacrylonitrile, triethylammonium 4-sulfamoylphenyldithiocarbamate, ammonium β-phenethyldithiocarbamate, and methyl N-(thiophene-2-sulfonyl)dithiocarbamate, only the last-named compound showed any radiation protection for mice. Several compounds gave negative tests for antimalarial activity

  15. Chemistry of the pyrazolidines. 26. Alkylation of 4-benzyliden-1-phenyl-3,5-dioxopyrazolidines

    International Nuclear Information System (INIS)

    Moldarev, B.L.; Aronzon, M.E.; Adanin, V.M.; Zyakun, A.M.

    1986-01-01

    The reaction of 4-benzyliden-1-phenyl-3,5-dioxopyrazolidines with alkyl halides in the presence of sodium alkoxide gave 1-phenyl-2-alkyl-4-benzyliden- and 1-phenyl-2,4-dialkyl-4-(α-alkoxybenzyl)-3,4-dioxopyrazolines. The structures of these compounds were confirmed by UV, IR, and PMR spectroscopy, and by mass-spectrometry

  16. Ionoluminescence properties of polystyrene-hosted fluorophore films induced by helium ions of energy 50-350 keV

    Science.gov (United States)

    Chakraborty, Subha; Huang, Mengbing

    2017-10-01

    We report on measurements and analysis of ionoluminescence properties of pure polystyrene films and polystyrene films doped with four types of fluorophores in low kinetic energies (50-350 keV) of ion irradiation. We have developed a theoretical model to understand the experimentally observed ionoluminescence behaviors in terms of scintillation yield from individual ion tracks, photophysical energy transfer mechanisms, and irradiation-induced defects. A comparison of the model and experimental results suggests that singlet up-conversion resulting from triplet-triplet annihilation processes may be responsible for enhanced singlet emission of the fluorophores at high ion beam flux densities. Energy transfer from the polystyrene matrix to the fluorophore molecules has been identified as an effective pathway to increasing the fluorescence efficiency in the doped scintillator films.

  17. Förster resonance energy transfer: Role of diffusion of fluorophore orientation and separation in observed shifts of FRET efficiency.

    Directory of Open Access Journals (Sweden)

    Bram Wallace

    Full Text Available Förster resonance energy transfer (FRET is a widely used single-molecule technique for measuring nanoscale distances from changes in the non-radiative transfer of energy between donor and acceptor fluorophores. For macromolecules and complexes this observed transfer efficiency is used to infer changes in molecular conformation under differing experimental conditions. However, sometimes shifts are observed in the FRET efficiency even when there is strong experimental evidence that the molecular conformational state is unchanged. We investigate ways in which such discrepancies can arise from kinetic effects. We show that significant shifts can arise from the interplay between excitation kinetics, orientation diffusion of fluorophores, separation diffusion of fluorophores, and non-emitting quenching.

  18. Quantitative detection of multiple fluorophore sites as a tool for diagnosis and monitoring disease progression in salivary glands

    Science.gov (United States)

    Gannot, Israel; Bonner, Robert F.; Gannot, Gallya; Fox, Philip C.; You, Joon S.; Waynant, Ronald W.; Gandjbakhche, Amir H.

    1997-08-01

    A series of fluorescent surface images were obtained from physical models of localized fluorophores embedded at various depths and separations in tissue phantoms. Our random walk theory was applied to create an analytical model of multiple flurophores embedded in tissue-like phantom. Using this model, from acquired set of surface images, the location of the fluorophores was reconstructed and compared it to their known 3-D distributions. A good correlation was found, and the ability to resolve fluorophores as a function of depth and separation was determined. In parallel in in-vitro study, specific coloring of sections of minor salivary glands was also demonstrated. These results demonstrate the possibility of using inverse methods to reconstruct unknown locations and concentrations of optical probes specifically bound to infiltrating lymphocytes in minor salivary glands of patients with Sjogren's syndrome.

  19. Electrochemical characterization of azo dye (E)-1-(4-((4-(phenylamino)phenyl)diazenyl)phenyl)ethanone (DPA)

    International Nuclear Information System (INIS)

    Surucu, Ozge; Abaci, Serdar; Seferoğlu, Zeynel

    2016-01-01

    Highlights: • Electrochemical characterization of azo dye DPA was performed. • Pencil graphite electrode was used as working electrode. • Cyclic voltammetry was used to determine the effect of scan rate and pH. • Chronoamperometry was used to determine diffusion constant. • Square wave voltammetry verified the results of cyclic voltammetry. - Abstract: An enormous range of possible dyes are available, especially as the starting molecules are readily available and cheap. As other dye classes become less viable from either an environmental or economic reasons, azo dyes come to the forefront. Therefore, electrochemical characterization of a novel synthesized azo dye (E)-1-(4-((4-(phenylamino) phenyl)diazenyl)phenyl)ethanone was achieved for the first time. Cyclic voltammetry, chronoamperometry and square wave voltammetry techniques were used to investigate the electrochemical behavior and electrocatalytic effect of azo dye (E)-1-(4-((4-(phenylamino) phenyl)diazenyl)phenyl)ethanone at pencil graphite electrode. Cyclic voltammograms were utilized to determine the effect of scan rate and pH on the peak current and peak potential. Chronoamperometry technique was used to determine diffusion constant, D and the type of adsorption isotherms. The kinetics parameters which were the apparent electron transfer rate constant, k s and charge transfer coefficient, α were calculated. Square wave voltammetry was used to verify responses of cyclic voltammetry technique.

  20. How nanoparticles encapsulating fluorophores allow a double detection of biomolecules by localized surface plasmon resonance and luminescence

    International Nuclear Information System (INIS)

    Barbillon, G; Faure, A C; Kork, N El; Moretti, P; Roux, S; Tillement, O; Ou, M G; Descamps, A; Perriat, P; Vial, A; Bijeon, J-L; Marquette, C A; Jacquier, B

    2008-01-01

    The paper shows how polysiloxane particles encapsulating fluorophores can be successfully used to detect biotin-streptavidin binding by two types of technique. After functionalization of the particles by streptavidin, the fixation of the biomolecule can indeed be detected by a shift of the localized surface plasmon resonance of the biotinylated gold dots used as substrate and by the luminescence of the fluorophores evidenced by scanning near-field optical microscopy. The development of particles allowing such a double detection opens a route for increasing the reliability of biological detection and for multi-labelling strategies crossing both detection principles

  1. How nanoparticles encapsulating fluorophores allow a double detection of biomolecules by localized surface plasmon resonance and luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Barbillon, G; Faure, A C; Kork, N El; Moretti, P [Universite de Lyon, Universite Lyon 1, CNRS UMR 5620, Laboratoire de Physico-Chimie des Materiaux Luminescents (LPCML), Domaine Scientifique de La Doua, Bat Kastler, 10 rue Andre Marie Ampere 69622 Villeurbanne Cedex (France); Roux, S; Tillement, O [Universite de Lyon, Universite Lyon 1, CNRS UMR 5620, Laboratoire de Physico-Chimie des Materiaux Luminescents (LPCML), Domaine Scientifique de La Doua, Bat Kastler, 10 rue Andre Marie Ampere 69622 Villeurbanne Cedex (France); Ou, M G; Descamps, A; Perriat, P [Materiaux, Ingenierie et Sciences (MATEIS), CNRS UMR 5510, Universite de Lyon, INSA-Lyon, Domaine Scientifique de La Doua, 7 avenue Jean Capelle 69621 Villeurbanne Cedex (France); Vial, A; Bijeon, J-L [Institut Charles Delaunay, CNRS FRE 2848, Laboratoire de Nanotechnologie et d' Instrumentation Optique (LNIO), Universite de Technologie de Troyes, 12 rue Marie Curie BP 2060 10010 Troyes Cedex (France); Marquette, C A [Laboratoire de Genie Enzymatique et Biomoleculaire, UMR 5246 CNRS-ICBMS, Universite de Lyon, Universite Lyon 1, 69622 Villeurbanne Cedex (France); Jacquier, B [Universite de Lyon, Universite Lyon 1, CNRS UMR 5620, Laboratoire de Physico-Chimie des Materiaux Luminescents (LPCML), Domaine Scientifique de La Doua, Bat Kastler, 10 rue Andre Marie Ampere 69622 Villeurbanne Cedex (France)

    2008-01-23

    The paper shows how polysiloxane particles encapsulating fluorophores can be successfully used to detect biotin-streptavidin binding by two types of technique. After functionalization of the particles by streptavidin, the fixation of the biomolecule can indeed be detected by a shift of the localized surface plasmon resonance of the biotinylated gold dots used as substrate and by the luminescence of the fluorophores evidenced by scanning near-field optical microscopy. The development of particles allowing such a double detection opens a route for increasing the reliability of biological detection and for multi-labelling strategies crossing both detection principles.

  2. Cu(II) recognition materials: Fluorophores grafted on mesoporous silica supports

    International Nuclear Information System (INIS)

    Kledzik, Krzysztof; Orlowska, Maja; Patralska, Dorota; Gwiazda, Marcin; Jezierska, Julia; Pikus, Stanislaw; Ostaszewski, Ryszard; Klonkowski, Andrzej M.

    2007-01-01

    There were designed and synthesized naphthalene and pyrene derivatives consisting of fluorophore group and of receptor fragment with donor N and O atoms. These fluorosensors were covalently attached by grafting carboxyl group to surfaces of silica xerogel or mesoporous silicas (MCM-41 and MCM-48) functionalized either with 3-aminopropyl or 3-glycidoxypropyl groups. The pyrene derivatives 2 and 3 covalently grafted on MCM-48 silica functionalized with 3-aminopropyl groups are potential recognition elements of a fluorescence chemical sensor. Fluorescence emission of the prepared recognition materials is quenched specifically owing to photoinduced electron transfer (PET) effect after coordination reactions with Cu(II) ions. Moreover, both the materials exhibit selectivity for Cu(II) ions in aqueous solutions in presence of such metal ions as: alkali, alkaline earth and transition. During UV irradiation the studied recognition elements undergo slowly photochemical degradation

  3. Fluorophores, environments, and quantification techniques in the analysis of transmembrane helix interaction using FRET.

    Science.gov (United States)

    Khadria, Ambalika S; Senes, Alessandro

    2015-07-01

    Förster resonance energy transfer (FRET) has been widely used as a spectroscopic tool in vitro to study the interactions between transmembrane (TM) helices in detergent and lipid environments. This technique has been instrumental to many studies that have greatly contributed to quantitative understanding of the physical principles that govern helix-helix interactions in the membrane. These studies have also improved our understanding of the biological role of oligomerization in membrane proteins. In this review, we focus on the combinations of fluorophores used, the membrane mimetic environments, and measurement techniques that have been applied to study model systems as well as biological oligomeric complexes in vitro. We highlight the different formalisms used to calculate FRET efficiency and the challenges associated with accurate quantification. The goal is to provide the reader with a comparative summary of the relevant literature for planning and designing FRET experiments aimed at measuring TM helix-helix associations. © 2015 Wiley Periodicals, Inc.

  4. Selenium as an alternative peptide label - comparison to fluorophore-labelled penetratin

    DEFF Research Database (Denmark)

    Hyrup Møller, Laura; Bahnsen, Jesper Søborg; Nielsen, Hanne Mørck

    2015-01-01

    lysates, primarily the intact peptide (PenMSe, TAMRA-PenMSe or TAMRA-Pen) was observed. Selenium labelling caused minimal alteration of the physicochemical properties of the peptide and allowed for absolute quantitative determination of cellular uptake by inductively coupled plasma mass spectrometry......In the present study, the impact on peptide properties of labelling peptides with the fluorophore TAMRA or the selenium (Se) containing amino acid SeMet was evaluated. Three differently labelled variants of the cell-penetrating peptide (CPP) penetratin (Pen) were synthesized, PenMSe, TAMRA....... Selenium is thus proposed as a promising alternative label for quantification of peptides in general, altering the properties of the peptide to a minor extent as compared to commonly used peptide labels....

  5. Synthesis and in vivo evaluation of 5-chloro-5-benzobarbiturates as new central nervous system depressants

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Andreia A.; Gomes, Niele M.; Matheus, Maria E.; Figueroa-Villar, Jose D., E-mail: figueroa@ime.eb.b [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Dept. de Chemistry. Medicinal Chemistry Grupo; Fernandes, Patricia D. [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Ciencias Biomedicas. Lab. de Farmacologia da Inflamacao e do Oxido Nitrico

    2011-07-01

    A new family of barbiturates, 5-chloro-5-benzylbarbituric acids, was prepared using a simple efficient synthetic method from aromatic aldehydes and barbituric acid, followed by reduction and chlorination with trichloro-isocyanuric acid, affording overall yields of 53 to 70%. The in vivo evaluation with mice showed that these compounds present tranquilizing activity. (author)

  6. Synthesis and in vivo evaluation of 5-chloro-5-benzobarbiturates as new central nervous system depressants

    International Nuclear Information System (INIS)

    Vieira, Andreia A.; Gomes, Niele M.; Matheus, Maria E.; Figueroa-Villar, Jose D.; Fernandes, Patricia D.

    2011-01-01

    A new family of barbiturates, 5-chloro-5-benzylbarbituric acids, was prepared using a simple efficient synthetic method from aromatic aldehydes and barbituric acid, followed by reduction and chlorination with trichloro-isocyanuric acid, affording overall yields of 53 to 70%. The in vivo evaluation with mice showed that these compounds present tranquilizing activity. (author)

  7. An efficient synthesis and biological study of substituted 8-chloro-5 ...

    Indian Academy of Sciences (India)

    peroxide in glacial acetic acid, 4H-1,4-benzothiazine-1,1-dioxides (sulphones) were synthesized. ... methanol. 2.2a 8-Chloro-2-trifluoroacetyl-3-trifluoromethyl-5- methoxy-4H-1 .... filtered and washed with water and recrystallized from ethanol.

  8. Nucleophilic Substitution and Redox Reactions with alpha-Chloro beta-Oxo Sulfenyl Chlorides

    DEFF Research Database (Denmark)

    El-Essawy, Farag A.G.; Yassin, Salah M.; El-Sakka, Ibrahim A.

    1998-01-01

    Alpha-Chloro sulfenyl chlorides such as 1 and 4 could not be reduced to the corresponding disulfides. Under reducing conditions they are instead dechlorinated to the corresponding thiocarbonyl compounds. Starting from the chroman-4-one derivatives 1 a number of 1,3,4-oxadithiins 3 have been prepa...

  9. Gelation Behavior of 5-Chloro-8-hydroxyquinoline, an Antituberculosis Agent in Aqueous Alcohol Solutions

    Directory of Open Access Journals (Sweden)

    Jukka Korpela

    2012-09-01

    Full Text Available It was shown that 5-chloro-8-hydroxyquinoline, an antituberculosis agent, gels aqueous alcohol solutions efficiently. Thermal stability and gel-to-sol transition temperature of 1% gel in CD3OD/D2O (2:1 was studied by 1H-NMR. Fibrous structures of four xerogels have been characterized by scanning electron microscope.

  10. New contributions to the chemistry of 2-chloro-2-(chlorothio)propanedioic diesters and diamides

    DEFF Research Database (Denmark)

    Hawata, Mohamed A.M.; El-Torgoman, Abdel M.; El-Kousy, Salah M.

    2002-01-01

    The pyridine-catalyzed reaction between a number of propanedioic acid derivatives 1 and thionyl chloride has been investigated in detail. Contrary to popular belief the straightforward formation of the corresponding alpha-chloro sulfenyl chlorides 2 is the exception rather than the rule. The prop...

  11. ChloroMitoCU: Codon patterns across organelle genomes for functional genomics and evolutionary applications.

    Science.gov (United States)

    Sablok, Gaurav; Chen, Ting-Wen; Lee, Chi-Ching; Yang, Chi; Gan, Ruei-Chi; Wegrzyn, Jill L; Porta, Nicola L; Nayak, Kinshuk C; Huang, Po-Jung; Varotto, Claudio; Tang, Petrus

    2017-06-01

    Organelle genomes are widely thought to have arisen from reduction events involving cyanobacterial and archaeal genomes, in the case of chloroplasts, or α-proteobacterial genomes, in the case of mitochondria. Heterogeneity in base composition and codon preference has long been the subject of investigation of topics ranging from phylogenetic distortion to the design of overexpression cassettes for transgenic expression. From the overexpression point of view, it is critical to systematically analyze the codon usage patterns of the organelle genomes. In light of the importance of codon usage patterns in the development of hyper-expression organelle transgenics, we present ChloroMitoCU, the first-ever curated, web-based reference catalog of the codon usage patterns in organelle genomes. ChloroMitoCU contains the pre-compiled codon usage patterns of 328 chloroplast genomes (29,960 CDS) and 3,502 mitochondrial genomes (49,066 CDS), enabling genome-wide exploration and comparative analysis of codon usage patterns across species. ChloroMitoCU allows the phylogenetic comparison of codon usage patterns across organelle genomes, the prediction of codon usage patterns based on user-submitted transcripts or assembled organelle genes, and comparative analysis with the pre-compiled patterns across species of interest. ChloroMitoCU can increase our understanding of the biased patterns of codon usage in organelle genomes across multiple clades. ChloroMitoCU can be accessed at: http://chloromitocu.cgu.edu.tw/. © The Author 2017. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.

  12. Problems of fluorescent imaging and its solution using nanofluorophores. Part I: Advantages of fluorescent nanoparticles over conventional organic fluorophores

    International Nuclear Information System (INIS)

    Zhelev, Z.; Hadjidekov, G.; Zlateva, G.; Spasov, L.; Bakalova, R.

    2011-01-01

    The application of fluorescence in deep-tissue imaging is rapidly expanding in fast several years. The progress in fluorescent molecular probes and fluorescent imaging techniques gives an opportunity to detect single cells and even molecules in live organisms. The highly sensitive and high-speed fluorescent molecular sensors and detection devices allow the application of fluorescence in functional imaging. With development of novel bright fluorophores based on nano-technologies and fluorescence scanners with high spatial and temporal resolution, the fluorescent imaging has a potential to become an alternative of the other non-invasive imaging techniques as magnetic resonance imaging, positron-emission tomography, X-ray, computing tomography. This review outlines the current status and future trends of fluorescent nanoparticles - quantum dots (QDs), as a new generation of fluorophores in experimental and pre-clinical fluorescent imaging diagnostic. Part 1 focuses on the advantages of quantum dots over conventional organic fluorophores and defines the major requirements to the 'perfect' fluorophore for fluorescent deep-tissue imaging diagnostic. The analysis is based on the limitations of fluorescent imaging in vivo and overcome by using quantum dots

  13. A green-light-emitting, spontaneously blinking fluorophore based on intramolecular spirocyclization for dual-colour super-resolution imaging.

    Science.gov (United States)

    Uno, Shin-Nosuke; Kamiya, Mako; Morozumi, Akihiko; Urano, Yasuteru

    2017-12-19

    We have developed the first green-light-emitting, spontaneously blinking fluorophore (SBF), HEtetTFER. In combination with our near-infrared-light-emitting SBF (HMSiR), HEtetTFER allows dual-colour single-molecule localization microscopy (SMLM) in buffer solution without any additive and without photoactivation.

  14. Steady state and time resolved fluorescence studies of azadioxatriangulenium (ADOTA) fluorophore in silica and PVA thin films

    DEFF Research Database (Denmark)

    Chib, Rahul; Raut, Sangram; Shah, Sunil

    2015-01-01

    A cationic azadioxatriangulenium dye was entrapped in silica thin films obtained by the sol-gel process and in poly (vinyl) alcohol (PVA) thin films. Azadioxatriangulenium is a red emitting fluorophore with a long fluorescence lifetime of ∼20 ns. The fluorescent properties of azadioxatriangulenium...

  15. Interactions between stacked layers of phenyl-modified silicene

    International Nuclear Information System (INIS)

    Spencer, Michelle J S; Snook, Ian K; Bassett, Michael R; Morishita, Tetsuya; Nakano, Hideyuki

    2013-01-01

    We use density functional theory (DFT) calculations to determine the interaction between phenyl-modified silicene nanosheets. The adhesion energy curves between the nanosheets are compared for different van der Waals density functional (vdW-DF) functionals and the DFT-D2 Grimme method. Our results show that there is a weak attraction between the sheets at close separations, that is stronger when vdWs forces are included. Without including vdWs forces the interaction is negligible and occurs at a much larger separation, highlighting the need to include such forces when modelling these nanosheets. Of the vdWs methods, the optB88 functional gives the strongest interaction energy while the Grimme gives the weakest, with the separation at which the nanosheets adhere more strongly varying between 10.04 and 11.24 Å, as measured by the distance between the silicene layers. As the modified nanosheets are brought closer together at separations as close at  ∼ 8 Å, the phenyl groups on the bottom of one nanosheet can fit in between the phenyl groups on the top of the adjacent nanosheet allowing some π − π interaction between the phenyl groups. We showed that the band gap can be modified by compressing the nanosheets together while retaining a small attraction between them. There is also a change from a direct to an indirect band gap. Such a property may be exploited for the application of these nanomaterials in optoelectronic devices. (paper)

  16. Toehold-mediated internal control to probe the near-field interaction between the metallic nanoparticle and the fluorophore

    Science.gov (United States)

    Ang, Y. S.; Yung, L. Y. L.

    2014-10-01

    Metallic nanoparticles (MNPs) are known to alter the emission of vicinal fluorophores through the near-field interaction, leading to either fluorescence quenching or enhancement. Much ambiguity remains in the experimental outcome of such a near-field interaction, particularly for bulk colloidal solution. It is hypothesized that the strong far-field interference from the inner filter effect of the MNPs could mask the true near-field MNP-fluorophore interaction significantly. Thus, in this work, a reliable internal control capable of decoupling the near-field interaction from far-field interference is established by the use of the DNA toehold concept to mediate the in situ assembly and disassembly of the MNP-fluorophore conjugate. A model gold nanoparticle (AuNP)-Cy3 system is used to investigate our proposed toehold-mediated internal control system. The maximum fluorescence enhancement is obtained for large-sized AuNP (58 nm) separated from Cy3 at an intermediate distance of 6.8 nm, while fluorescence quenching is observed for smaller-sized AuNP (11 nm and 23 nm), which is in agreement with the theoretical values reported in the literature. This work shows that the toehold-mediated internal control design can serve as a central system for evaluating the near-field interaction of other MNP-fluorophore combinations and facilitate the rational design of specific MNP-fluorophore systems for various applications.Metallic nanoparticles (MNPs) are known to alter the emission of vicinal fluorophores through the near-field interaction, leading to either fluorescence quenching or enhancement. Much ambiguity remains in the experimental outcome of such a near-field interaction, particularly for bulk colloidal solution. It is hypothesized that the strong far-field interference from the inner filter effect of the MNPs could mask the true near-field MNP-fluorophore interaction significantly. Thus, in this work, a reliable internal control capable of decoupling the near

  17. ChloroP, a neural network-based method for predicting chloroplast transitpeptides and their cleavage sites

    DEFF Research Database (Denmark)

    Emanuelsson, O.; Nielsen, Henrik; von Heijne, Gunnar

    1999-01-01

    the cleavage sites given in SWISS-PROT. An analysis of 715 Arabidopsis thaliana sequences from SWISS-PROT suggests that the ChloroP method should be useful for the identification of putative transit peptides in genome-wide sequence data. The ChloroP predictor is available as a web-server at http......We present a neural network based method (ChloroP) for identifying chloroplast transit peptides and their cleavage sites. Using cross-validation, 88% of the sequences in our homology reduced training set were correctly classified as transit peptides or nontransit peptides. This performance level...

  18. Fragrance material review on 4-phenyl-3-buten-2-ol.

    Science.gov (United States)

    Scognamiglio, J; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 4-phenyl-3-buten-2-ol when used as a fragrance ingredient is presented. 4-Phenyl-3-buten-2-ol is a member of the fragrance structural group Aryl Alkyl Alcohols and is a secondary alcohol. The AAAs are a structurally diverse class of fragrance ingredients that includes primary, secondary, and tertiary alkyl alcohols covalently bonded to an aryl (Ar) group, which may be either a substituted or unsubstituted benzene ring. The common structural element for the AAA fragrance ingredients is an alcohol group -C-(R1)(R2)OH and generically the AAA fragrances can be represented as an Ar-C-(R1)(R2)OH or Ar-Alkyl-C-(R1)(R2)OH group. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 4-phenyl-3-buten-2-ol were evaluated then summarized and includes physical properties, and genotoxicity data. A safety assessment of the entire Aryl Alkyl Alcohols will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all Aryl Alkyl Alcohols in fragrances. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Fragrance material review on 2-methyl-4-phenyl-2-butanol.

    Science.gov (United States)

    Scognamiglio, J; Jones, L; Letizia, C S; Api, A M

    2012-09-01

    A toxicologic and dermatologic review of 2-methyl-4-phenyl-2-butanol when used as a fragrance ingredient is presented. 2-methyl-4-phenyl-2-butanol is a member of the fragrance structural group Aryl Alkyl Alcohols and is a tertiary alcohol. The AAAs are a structurally diverse class of fragrance ingredients that includes primary, secondary, and tertiary alkyl alcohols covalently bonded to an aryl (Ar) group, which may be either a substituted or unsubstituted benzene ring. The common structural element for the AAA fragrance ingredients is an alcohol group -C-(R1)(R2)OH and generically the AAA fragrances can be represented as an Ar-C-(R1)(R2)OH or Ar-Alkyl-C-(R1)(R2)OH group. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for 2-methyl-4-phenyl-2-butanol were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, and skin sensitization data. A safety assessment of the entire Aryl Alkyl Alcohols will be published simultaneously with this document; please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all Aryl Alkyl Alcohols in fragrances. assessment of aryl alkyl alcohols when used as fragrance ingredients. Copyright © 2011 Elsevier Ltd. All rights reserved.

  20. Structure-guided approach to site-specific fluorophore labeling of the lac repressor LacI.

    Directory of Open Access Journals (Sweden)

    Kalle Kipper

    Full Text Available The lactose operon repressor protein LacI has long served as a paradigm of the bacterial transcription factors. However, the mechanisms whereby LacI rapidly locates its cognate binding site on the bacterial chromosome are still elusive. Single-molecule fluorescence imaging approaches are well suited for the study of these mechanisms but rely on a functionally compatible fluorescence labeling of LacI. Particularly attractive for protein fluorescence labeling are synthetic fluorophores due to their small size and favorable photophysical characteristics. Synthetic fluorophores are often conjugated to natively occurring cysteine residues using maleimide chemistry. For a site-specific and functionally compatible labeling with maleimide fluorophores, the target protein often needs to be redesigned to remove unwanted native cysteines and to introduce cysteines at locations better suited for fluorophore attachment. Biochemical screens can then be employed to probe for the functional activity of the redesigned protein both before and after dye labeling. Here, we report a mutagenesis-based redesign of LacI to enable a functionally compatible labeling with maleimide fluorophores. To provide an easily accessible labeling site in LacI, we introduced a single cysteine residue at position 28 in the DNA-binding headpiece of LacI and replaced two native cysteines with alanines where derivatization with bulky substituents is known to compromise the protein's activity. We find that the redesigned LacI retains a robust activity in vitro and in vivo, provided that the third native cysteine at position 281 is retained in LacI. In a total internal reflection microscopy assay, we observed individual Cy3-labeled LacI molecules bound to immobilized DNA harboring the cognate O1 operator sequence, indicating that the dye-labeled LacI is functionally active. We have thus been able to generate a functional fluorescently labeled LacI that can be used to unravel mechanistic

  1. Synthesis and characterization of new fluorescent styrene-containing carborane derivatives: the singular quenching role of a phenyl substituent.

    Science.gov (United States)

    Ferrer-Ugalde, Albert; Juárez-Pérez, Emilio José; Teixidor, Francesc; Viñas, Clara; Sillanpää, Reijo; Pérez-Inestrosa, Ezequiel; Núñez, Rosario

    2012-01-09

    A set of neutral and anionic carborane derivatives in which the styrenyl fragment is introduced as a fluorophore group has been successfully synthesized and characterized. The reaction of the monolithium salts of 1-Ph-1,2-C(2)B(10)H(11), 1-Me-1,2-C(2)B(10)H(11) and 1,2-C(2)B(10)H(12) with one equivalent of 4-vinylbenzyl chloride leads to the formation of compounds 1-3, whereas the reaction of the dilithium salt of 1,2-C(2)B(10)H(12) with two equivalents of 4-vinylbenzyl chloride gives disubstituted compound 4. The closo clusters were degraded using the classical method, KOH in EtOH, to afford the corresponding nido species, which were isolated as tetramethylammonium salts. The crystal structure of the four closo compounds 1-4 were analyzed by X-ray diffraction. All compounds, except 1, display emission properties, with quantum yields dependent on the nature of the cluster (closo or nido) and the substituent on the second C(cluster) atom. In general, closo compounds 2-4 exhibit high fluorescence emission, whereas the presence of a nido cluster produces a decrease of the emission intensity. The presence of a phenyl group bonded to the C(cluster) results in an excellent electron-acceptor unit that produces a quenching of the fluorescence. DFT calculations have confirmed the charge-separation state in 1 to explain the quenching of the fluorescence and the key role of the carboranyl fragment in this luminescent process. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Cytotoxicity, genotoxicity, and mutagenicity of 1-chloro-2-hydroxy-3-butene and 1-chloro-3-buten-2-one, two alternative metabolites of 1,3-butadiene

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xin-Jie; Zeng, Fang-Mao; An, Jing; Yu, Ying-Xin [Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444 (China); Zhang, Xin-Yu, E-mail: xyzhang999@shu.edu.cn [Institute of Environmental Pollution and Health, School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444 (China); Elfarra, Adnan A., E-mail: elfarra@svm.vetmed.wisc.edu [Department of Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706 (United States); Molecular and Environmental Toxicology Center, University of Wisconsin-Madison, Madison, WI 53706 (United States)

    2013-08-15

    The cytotoxicity, genotoxicity, and mutagenicity of 1-chloro-2-hydroxy-3-butene (CHB), a known in vitro metabolite of the human carcinogen 1,3-butadiene, have not previously been investigated. Because CHB can be bioactivated by alcohol dehydrogenases to yield 1-chloro-3-buten-2-one (CBO), a bifunctional alkylating agent that caused globin-chain cross-links in erythrocytes, in the present study we investigated the cytotoxic and genotoxic potential of CHB and CBO in human normal hepatocyte L02 cells using the MTT assay, the relative cloning efficiency assay and the comet assay. We also investigated the mutagenic potential of these compounds with the Ames test using Salmonella strains TA1535 and TA1537. The results provide clear evidence for CHB and CBO being both cytotoxic and genotoxic with CBO being approximately 100-fold more potent than CHB. Interestingly, CHB generated both single-strand breaks and alkali-labile sites on DNA, whereas CBO produced only alkali-labile sites. CHB did not directly result in DNA breaks, whereas CBO was capable of directly generating breaks on DNA. Interestingly, both compounds did not induce DNA cross-links as examined by the comet assay. The Ames test results showed that CHB induced point mutation but not frameshift mutation, whereas the toxic effects of CBO made it difficult to reliably assess the mutagenic potential of CBO in the two strains. Collectively, the results suggest that CHB and CBO may play a role in the mutagenicity and carcinogenicity of 1,3-butadiene. - Highlights: • 1-Chloro-2-hydroxy-3-butene (CHB) is cytotoxic and genotoxic in human liver cells. • The CHB metabolite, 1-chloro-3-buten-2-one (CBO) is ∼ 100-fold more toxic than CHB. • CHB and CBO cause DNA alkali-labile sites, but only CBO directly causes DNA breaks. • CHB is mutagenic in the Ames test, but CBO is too toxic in the assay. • The results suggest a role for CHB in 1,3-butadiene genotoxicity and mutagenicity.

  3. Determination of 3-chloro-1,2-propanediol in polyamideamine epichlorohydrin resin solution by reaction-based headspace gas chromatography.

    Science.gov (United States)

    Yan, Ning; Wan, Xiao-Fang; Chai, Xin-Sheng; Chen, Run-Quan

    2018-04-01

    We report on a headspace gas chromatographic method for determining the content of 3-chloro-1,2-propanediol in polyamideamine epichlorohydrin resin solution. It was based on quantitatively converting 3-chloro-1,2-propanediol to formaldehyde by periodate oxidation in a closed headspace sample vial at a room temperature for 10 min, and then to methanol by borohydride reduction at 90°C for 40 min followed by the headspace gas chromatographic measurement. The results showed that the present method has an excellent measurement precision (relative standard deviation < 2.60%) and accuracy (recoveries from 96.4-102%) in 3-chloro-1,2-propanediol analysis. The limit of quantitation was 0.031 mg/mL. It is simple and suitable for determining the 3-chloro-1,2-propanediol content in polyamideamine epichlorohydrin resin solution. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Intramolecular didehydro-Diels-Alder reaction and its impact on the structure-function properties of environmentally sensitive fluorophores.

    Science.gov (United States)

    Brummond, Kay M; Kocsis, Laura S

    2015-08-18

    Reaction discovery plays a vital role in accessing new chemical entities and materials possessing important function.1 In this Account, we delineate our reaction discovery program regarding the [4 + 2] cycloaddition reaction of styrene-ynes. In particular, we highlight our studies that lead to the realization of the diverging reaction mechanisms of the intramolecular didehydro-Diels-Alder (IMDDA) reaction to afford dihydronaphthalene and naphthalene products. Formation of the former involves an intermolecular hydrogen atom abstraction and isomerization, whereas the latter is formed via an unexpected elimination of H2. Forming aromatic compounds by a unimolecular elimination of H2 offers an environmentally benign alternative to typical oxidation protocols. We also include in this Account ongoing work focused on expanding the scope of this reaction, mainly its application to the preparation of cyclopenta[b]naphthalenes. Finally, we showcase the synthetic utility of the IMDDA reaction by preparing novel environmentally sensitive fluorophores. The choice to follow this path was largely influenced by the impact this reaction could have on our understanding of the structure-function relationships of these molecular sensors by taking advantage of a de novo construction and functionalization of the aromatic portion of these compounds. We were also inspired by the fact that, despite the advances that have been made in the construction of small molecule fluorophores, access to rationally designed fluorescent probes or sensors possessing varied and tuned photophysical, spectral, and chemical properties are still needed. To this end, we report our studies to correlate fluorophore structure with photophysical property relationships for a series of solvatochromic PRODAN analogs and viscosity-sensitive cyanoacrylate analogs. The versatility of this de novo strategy for fluorophore synthesis was demonstrated by showing that a number of functional groups could be installed at

  5. CCDC 940299: Experimental Crystal Structure Determination : (mu~2~-Chloro)-(mu~2~-2-(1-(1-(dimethylamino)ethyl)naphthalen-2-yl)-2-phenyl-1-(phenyl(phenylethynyl)phosphanyl)ethenyl)-chloro-(1-(1-(dimethylamino)ethyl)naphthalen-2-yl)-palladium-platinum benzene solvate

    KAUST Repository

    Chen, Shuli

    2013-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  6. CCDC 940296: Experimental Crystal Structure Determination : (mu~2~-Chloro)-(mu~2~-2-(1-(1-(dimethylamino)ethyl)naphthalen-2-yl)-2-phenyl-1-(phenyl(phenylethynyl)phosphanyl)ethenyl)-chloro-(1-(1-(dimethylamino)ethyl)naphthalen-2-yl)-palladium-platinum acetone dichloromethane solvate

    KAUST Repository

    Chen, Shuli

    2013-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  7. CCDC 940295: Experimental Crystal Structure Determination : (mu~2~-Chloro)-(mu~2~-2-(1-(1-(dimethylamino)ethyl)naphthalen-2-yl)-2-phenyl-1-(phenyl(phenylethynyl)phosphanyl)ethenyl)-chloro-(1-(1-(dimethylamino)ethyl)naphthalen-2-yl)-di-palladium acetone dichloromethane solvate

    KAUST Repository

    Chen, Shuli

    2013-01-01

    An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

  8. Combining regio- and enantioselectivity of lipases for the preparation of (R)-4-chloro-2-butanol.

    Science.gov (United States)

    Méndez, Jonh J; Oromi, Mireia; Cervero, Maria; Balcells, Mercè; Torres, Mercè; Canela, Ramon

    2007-01-01

    Preparation of 98% ee (R)-4-chloro-2-butanol was carried out by the enzymatic hydrolysis of chlorohydrin esters, using fungal resting cells and commercial enzymes. Hydrolyzes were carried out using lipases from Candida antarctica (Novozym 435), C. rugosa, Rhizomucor miehei (Lipozyme IM), Burkolia cepacia, and resting cells of Rhizopus oryzae and Aspergillus flavus. The influence of the enzyme, the solvent, the temperature, and the alkyl chain length on the selectivity of hydrolyzes of isomeric mixtures of chlorohydrin esters is described. Regioselectivity was higher than 95% for some of the tested lipases. Novozym 435 allowed preparation of the (R)-4-chloro-2-butanol after 15 min of reaction at 30-40 degrees C. (c) 2006 Wiley-Liss, Inc.

  9. Functionalization of mesoporous silica membrane with a Schiff base fluorophore for Cu(II) ion sensing

    Energy Technology Data Exchange (ETDEWEB)

    Chen Xiaotong [Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku 980-8578, Sendai, Miyagi Prefecture (Japan); Department of Chemistry, Tsinghua University, Beijing 100084 (China); Yamaguchi, Akira [College of Science, Ibaraki University, Bunkyo 2-1-1, Mito, Ibaraki 310-8512 (Japan); Frontier Research Center for Applied Atomic Sciences, Ibaraki University, Tokai, Ibaraki 319-1106 (Japan); Namekawa, Manato [Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku 980-8578, Sendai, Miyagi Prefecture (Japan); Kamijo, Toshio [Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku 980-8578, Sendai, Miyagi Prefecture (Japan); Tsuruoka National College of Technology, Aza-Sawada, Tsuruoka 997-8511 (Japan); Teramae, Norio, E-mail: teramae@m.tohoku.ac.jp [Department of Chemistry, Graduate School of Science, Tohoku University, Aoba-ku 980-8578, Sendai, Miyagi Prefecture (Japan); Tong, Aijun, E-mail: tongaj@mail.tsinghua.edu.cn [Department of Chemistry, Tsinghua University, Beijing 100084 (China)

    2011-06-24

    Graphical abstract: Highlights: > A hybrid mesoporous membrane (SB-HMM) functionalized by Schiff base fluorophores was fabricated. > SB-HMM showed strong fluorescence with aggregation-induced emission enhancement properties. > SB-HMM was applicable for the detection of Cu(II) in an aqueous solution with good reversibility and reproducibility. - Abstract: A Schiff base (SB) immobilized hybrid mesoporous silica membrane (SB-HMM) was prepared by immobilizing a Schiff base onto the pore surface of mesoporous silica (pore size = 3.1 nm) embedded in the pores of a porous anodic alumina membrane. In contrast to the non-fluorescent analogous SB molecule in homogeneous solutions, SB-HMM exhibited intense fluorescence due to emission enhancement caused by aggregation of SB groups on the pore surface. The high quantum efficiency of the surface SB groups allows SB-HMM to function as a fluorescent sensor for Cu(II) ions in an aqueous solution with good sensitivity, selectivity and reproducibility. Under the optimal conditions described, the linear ranges of fluorescence intensity for Cu(II) are 1.2-13.8 (M (R{sup 2} = 0.993) and 19.4-60 (R{sup 2} = 0.992) (M. The limit of detection for Cu(II) is 0.8 {mu}M on basis of the definition by IUPAC (C{sub LOD} = 3.3S{sub b}/m).

  10. Oxygen sensing PLIM together with FLIM of intrinsic cellular fluorophores for metabolic mapping

    Science.gov (United States)

    Kalinina, Sviatlana; Schaefer, Patrick; Breymayer, Jasmin; Bisinger, Dominik; Chakrabortty, Sabyasachi; Rueck, Angelika

    2018-02-01

    Otical imaging techniques based on time correlated single photon counting (TCSPC) has found wide applications in medicine and biology. Non-invasive and information-rich fluorescence lifetime imaging microscopy (FLIM) is successfully used for monitoring fluorescent intrinsic metabolic coenzymes as NAD(P)H (nicotinamide adenine dinucleotide (phosphate)) and FAD+ (flavin adenine dinucleotide) in living cells and tissues. The ratio between proteinbound and free coenzymes gives an information about the balance between oxidative phosphorylation and glycolysis in the cells. The changes of the ratio reflects major cellular disorders. A correlation exists between metabolic activity, redox ratio and fluorescence lifetime during stem cell differentiation, neurodegenerative diseases, and carcinogenesis. A multichannel FLIM detection system was designed for monitoring the redox state of NAD(P)H and FAD+ and other intrinsic fluorophores as protoporphyrin IX. In addition, the unique upgrade is useful to perform FLIM and PLIM (phosphorescence lifetime imaging microscopy) simultaneously. PLIM is a promising method to investigate oxygen sensing in biomedical samples. In detail, the oxygen-dependent quenching of phosphorescence of some compounds as transition metal complexes enables measuring of oxygen partial pressure (pO2). Using a two-channel FLIM/PLIM system we monitored intrinsic pO2 by PLIM simultaneously with NAD(P)H by FLIM providing complex metabolic and redox imaging of living cells. Physico-chemical properties of oxygen sensitive probes define certain parameters including their localisation. We present results of some ruthenium based complexes including those specifically bound to mitochondria.

  11. Multimodal fluorescence molecular imaging for in vivo characterization of skin cancer using endogenous and exogenous fluorophores

    Science.gov (United States)

    Miller, Jessica P.; Habimana-Griffin, LeMoyne; Edwards, Tracy S.; Achilefu, Samuel

    2017-06-01

    Similarity of skin cancer with many benign skin pathologies requires reliable methods to detect and differentiate the different types of these lesions. Previous studies have explored the use of disparate optical techniques to identify and estimate the invasive nature of melanoma and basal cell carcinoma with varying outcomes. Here, we used a concerted approach that provides complementary information for rapid screening and characterization of tumors, focusing on squamous cell carcinoma (SCC) of the skin. Assessment of in vivo autofluorescence lifetime (FLT) imaging of endogenous fluorophores that are excitable at longer wavelengths (480 nm) than conventional NADH and FAD revealed a decrease in the short FLT component for SCC compared to normal skin, with mean values of 0.57±0.026 ns and 0.61±0.021 ns, respectively (p=0.004). Subsequent systemic administration of a near-infrared fluorescent molecular probe in SCC bearing mice, followed by the implementation of image processing methods on data acquired from two-dimensional and three-dimensional fluorescence molecular imaging, allowed us to estimate the tumor volume and depth, as well as quantify the fluorescent probe in the tumor. The result suggests the involvement of lipofuscin-like lipopigments and riboflavin in SCC metabolism and serves as a model for staging SCC.

  12. A laser scanner for imaging fluorophore labeled molecules in electrophoretic gels

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, D.J.; Sutherland, J.C. [Brookhaven National Lab., Upton, NY (United States). Biology Dept.

    1995-08-01

    A laser scanner for imaging electrophoretic gels was constructed and tested. The scanner incorporates a green helium-neon (HeNe) laser (543.5nm wavelength) and can achieve a spatial resolution of 19{micro}m. The instrument can function in two modes : snap-shot and finish-line. In snapshot mode, all samples are electrophoresed for the same time and the gel is scanned after completion of electrophoresis, while in finish-line mode, fluorophore labeled samples are electrophoresed for a constant distance and the image is formed as the samples pass under the detector. The resolving power of the finish-line mode of imaging is found to be greater than that of the snapshot mode of imaging. This laser scanner is also compared with a Charge Coupled Device (CCD) camera and in terms of resolving power is found to be superior. Sensitivity of the instrument is presented in terms of the minimum amount of DNA that can be detected verses its molecular length.

  13. Hyperfine interaction mechanism of magnetic field effects in sequential fluorophore and exciplex fluorescence.

    Science.gov (United States)

    Dodin, Dmitry V; Ivanov, Anatoly I; Burshtein, Anatoly I

    2013-03-28

    The magnetic field effect on the fluorescence of the photoexcited electron acceptor, (1)A∗, and the exciplex, (1)[D(+δ)A(-δ)] formed at contact of (1)A∗ with an electron donor (1)D, is theoretically explored in the framework of Integral Encounter Theory. It is assumed that the excited fluorophore is equilibrated with the exciplex that reversibly dissociates into the radical-ion pair. The magnetic field sensitive stage is the spin conversion in the resulting geminate radical-ion pair, (1, 3)[D(+)...A(-)] that proceeds due to hyperfine interaction. We confirm our earlier conclusion (obtained with a rate description of spin conversion) that in the model with a single nucleus spin 1/2 the magnitude of the Magnetic Field Effect (MFE) also vanishes in the opposite limits of low and high dielectric permittivity of the solvent. Moreover, it is shown that MFE being positive at small hyperfine interaction A, first increases with A but approaching the maximum starts to decrease and even changes the sign.

  14. Catecholamine uptake sites: characterization, localization, and a role in the production of N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced Parkinsonism

    International Nuclear Information System (INIS)

    Javitch, J.A.

    1985-01-01

    Dopamine and norepinephrine are inactivated by specific high affinity transport systems which mediate the recapture of the amines into presynaptic nerve terminals. [ 3 H]Maxindol labels neuronal dopamine uptake sites in corpus striatum membranes and neuronal norepinephrine uptake sites in cerebral cortex and submaxillary/sublingual gland membranes. The potencies of various inhibitors of biogenic amine uptake in reducing [ 3 H]mazindol binding in striatal membranes correlate with their potencies for inhibition of neurona [ 3 H]dopamine accumulation, whereas their potencies in reducing [ 3 H]mazindol binding to cortical and salivary gland membranes correlate with their potencies for inhibition of neuronal [ 3 H]norepinephrine accumulation. The association of [ 3 H]mazindol binding sites with neuronal dopamine uptake sites in the corpus striatum is further supported by the reduction of [ 3 H]mazindol binding sites in striatal membranes following destruction of dopaminergic neurons by 6-hydroxydopamine. Similarly, destruction of noradrenergic neurons by N-(2-chloro-ethyl)-N-ethyl-2-bromobenzylamine(DSP-4) decreases [ 3 H]mazindol binding to cortical membranes. Dopamine and norepinephrine uptake sites in rat brain have been differentially visualized using [ 3 H]mazindol autoradiography. N-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) produces neuropathologic and clinical abnormalities in humans and animals that closely resemble idiopathic Parkinson disease. [ 3 H]MPTP binds with high affinity to brain membranes. The chemical specificity of the binding sites corresponds to structure-activity requirements for neurotoxicity

  15. The thermal conductivity of 1-chloro-1,1-difluoroethane (HCFC-142b)

    Science.gov (United States)

    Sousa, A. T.; Fialho, P. S.; Nieto de Castro, C. A.; Tufeu, R.; Le Neindre, B.

    1992-05-01

    The thermal conductivity of 1-chloro-1,1-difluoroethane (HCFC-142b) has been measured in the temperature range 290 to 504 K and pressures up to 20 MPa with a concentric-cylinder apparatus operating in a steady-state mode. These temperature and pressure ranges cover all fluid states. The estimated accuracy of the method is about 2%. The density dependence of the thermal conductivity has been studied in the liquid region.

  16. Fourier transform infrared and FT-Raman spectra, assignment, ab initio, DFT and normal co-ordinate analysis of 2-chloro-4-methylaniline and 2-chloro-6-methylaniline.

    Science.gov (United States)

    Arjunan, V; Mohan, S

    2009-03-01

    The Fourier transform infrared (FTIR) and FT-Raman spectra of 2-chloro-4-methylaniline and 2-chloro-6-methylaniline have been measured in the range 4000-400 and 4000-100cm(-1), respectively. Utilising the observed FTIR and FT-Raman data, a complete vibrational assignment and analysis of the fundamental modes of the compounds were carried out. The vibrational frequency which were determined experimentally are compared with those obtained theoretically from ab initio HF and DFT gradient calculations employing the HF/6-31G(d,p) and B3LYP/6-31G(d,p) methods for optimised geometries. The geometries and normal modes of vibration obtained from the HF and DFT methods are in good agreement with the experimental data. The normal co-ordinate analysis was also carried out on the basis of ab initio force fields utilising Wilson's FG matrix method. The manifestations of NH-pi interactions and the influence of bulky chlorine and methyl group on the vibrational modes of the amino group are investigated.

  17. A comparative study on vibrational, conformational and electronic structure of 2-chloro-4-methyl-3-nitropyridine and 2-chloro-6-methylpyridine

    Science.gov (United States)

    Arjunan, V.; Saravanan, I.; Marchewka, Mariusz K.; Mohan, S.

    Experimental FTIR and FT-Raman spectroscopic analysis of 2-chloro-4-methyl-3-nitropyridine (2C4M3NP) and 2-chloro-6-methylpyridine (2C6MP) have been performed. A detailed quantum chemical calculations have been carried out using B3LYP and B3PW91 methods with 6-311++G** and cc-pVTZ basis sets. Conformation analysis was carried for 2C4M3NP and 2C6MP. The temperature dependence of thermodynamic properties has been analysed. The atomic charges, electronic exchange interaction and charge delocalisation of the molecule have been performed by natural bond orbital (NBO) analysis. Molecular electrostatic surface potential (MESP), total electron density distribution and frontier molecular orbitals (FMOs) are constructed at B3LYP/6-311++G** level to understand the electronic properties. The charge density distribution and site of chemical reactivity of the molecules have been obtained by mapping electron density isosurface with electrostatic potential surfaces (ESP). The electronic properties, HOMO and LUMO energies were measured by time-dependent TD-DFT approach.

  18. 1-Acetyl-5-ferrocenyl-3-phenyl-2-pyrazoline

    Directory of Open Access Journals (Sweden)

    Orhan Büyükgüngör

    2009-02-01

    Full Text Available In the title compound, [Fe(C5H5(C16H15N2O], the pyrazoline ring and the phenyl ring are nearly coplanar, making a dihedral angle of 6.54 (2°, while the substituted cyclopentadienyl ring is twisted out of the pyrazoline ring plane by 81.32 (1°. The molecules in the crystal structure are held together by weak C—H...O intermolecular hydrogen bonds and two C—H...π interactions.

  19. Radiation initiated polymerisation of phenyl methacrylate. [Gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Raghunath, S.; Rao, M.H.; Rao, K.N. (Bhabha Atomic Research Centre, Bombay (India). Chemistry Div.)

    1983-01-01

    Radiation initiated polymerisation of phenyl methacrylate has been studied at various dose rates and temperature. Predominant chain transfer to the monomer was observed and ksub(tran)/Ksub(p) the chain transfer constant ratio was found to be 4 x 10/sup -2/.ksub(p)/ksub(tsup(1/2)) value determined by the kinetic data and the molecular weight data were 0.0821 and 0.0198, respectively. IR studies of polymer at low conversion showed the presence of terminal unsaturation which disappeared at saturation conversion, thus showing its participation in the formation of a three dimensional network.

  20. Biophysical properties of phenyl succinic acid derivatised hyaluronic acid

    DEFF Research Database (Denmark)

    Neves-Petersen, Maria Teresa; Klitgaard, Søren; Skovsen, Esben

    2010-01-01

    Modification of hyaluronic acid (HA) with aryl succinic anhydrides results in new biomedical properties of HA as compared to non-modified HA, such as more efficient skin penetration, stronger binding to the skin, and the ability to blend with hydrophobic materials. In the present study, hyaluronic...... acid has been derivatised with the anhydride form of phenyl succinic acid (PheSA). The fluorescence of PheSA was efficiently quenched by the HA matrix. HA also acted as a singlet oxygen scavenger. Fluorescence lifetime(s) of PheSA in solution and when attached to the HA matrix has been monitored...

  1. Ruthenium(II) carbonyl compounds with the 4'-chloro-2,2':6',2''-terpyridine ligand.

    Science.gov (United States)

    Tatikonda, Rajendhraprasad; Haukka, Matti

    2017-04-01

    Two ruthenium carbonyl complexes with the 4'-chloro-2,2':6',2''-terpyridine ligand (tpy-Cl, C 15 H 10 ClN 3 ), i.e. [RuCl(tpy-Cl)(CO) 2 ][RuCl 3 (CO) 3 ] (I) [systematic name: cis -di-carbonyl-chlorido(4'-chloro-2,2':6',2''-terpyridine-κ 3 N )ruthenium(II) fac -tricarbonyltri-chlorido-ruthenate(II)], and [RuCl 2 (tpy-Cl)(CO) 2 ] (II) [ cis -dicarbonyl- trans -di-chlorido(4'-chloro-2,2':6',2''-terpyridine-κ 2 N 1 , N 1' )ruthenium(II)], were synthesized and characterized by single-crystal X-ray diffraction. The Ru II atoms in both centrosymmetric structures (I) and (II) display similar, slightly distorted octa-hedral coordination spheres. The coordination sphere in the complex cation in compound (I) is defined by three N atoms of the tridentate tpy-Cl ligand, two carbonyl carbon atoms and one chlorido ligand; the charge is balanced by an octa-hedral [Ru(CO) 3 Cl 3 ] - counter-anion. In the neutral compound (II), the tpy-Cl ligand coordinates to the metal only through two of its N atoms. The coordination sphere of the Ru II atom is completed by two carbonyl and two chlorido ligands. In the crystal structures of both (I) and (II), weak C-H⋯Cl inter-actions are observed.

  2. High-resolution of particle contacts via fluorophore exclusion in deep-imaging of jammed colloidal packings

    Science.gov (United States)

    Kyeyune-Nyombi, Eru; Morone, Flaviano; Liu, Wenwei; Li, Shuiqing; Gilchrist, M. Lane; Makse, Hernán A.

    2018-01-01

    Understanding the structural properties of random packings of jammed colloids requires an unprecedented high-resolution determination of the contact network providing mechanical stability to the packing. Here, we address the determination of the contact network by a novel strategy based on fluorophore signal exclusion of quantum dot nanoparticles from the contact points. We use fluorescence labeling schemes on particles inspired by biology and biointerface science in conjunction with fluorophore exclusion at the contact region. The method provides high-resolution contact network data that allows us to measure structural properties of the colloidal packing near marginal stability. We determine scaling laws of force distributions, soft modes, correlation functions, coordination number and free volume that define the universality class of jammed colloidal packings and can be compared with theoretical predictions. The contact detection method opens up further experimental testing at the interface of jamming and glass physics.

  3. Absorption and fluorescence spectroscopy of 3-hydroxy-3-phenyl-1-o-carboxyphenyltriazene and its copper (II), nickel (II) and zinc (II) complexes: a novel fluorescence sensor

    International Nuclear Information System (INIS)

    Ressalan, S.; Iyer, C.S.P.

    2005-01-01

    Absorption and fluorescence spectroscopic properties of 3-hydroxy-3-phenyl-1-o-carboxyphenyltriazene (HT) are studied. The mechanism of photo-induced electron transfer (PET) followed by energy transfer process of the ligand and the Cu (II), Ni (II) and Zn (II) metal complexes have been investigated. The excited state photo induced intramolecular hydrogen transfer from N-OH to triazene 1-nitrogen atom is explained. The effect of pH, solvent and concentration on the absorption and fluorescence of the ligand is studied and it has been found that the absorption and fluorescence of HT is highly pH, solvent and concentration dependent. Participation of the N-OH proton of HT in the solvent assisted O to N-proton transfer has also been proposed. The fluorescence band shift and changes in intensity is modulated by protonation and complexation with metal ions. This fluorophore can thus be used as a pH dependent and M (n+1)+ /M n+ redox on/off switchable molecular sensor

  4. Ratiometric fluorescent sensing of pH values in living cells by dual-fluorophore-labeled i-motif nanoprobes.

    Science.gov (United States)

    Huang, Jin; Ying, Le; Yang, Xiaohai; Yang, Yanjing; Quan, Ke; Wang, He; Xie, Nuli; Ou, Min; Zhou, Qifeng; Wang, Kemin

    2015-09-01

    We designed a new ratiometric fluorescent nanoprobe for sensing pH values in living cells. Briefly, the nanoprobe consists of a gold nanoparticle (AuNP), short single-stranded oligonucleotides, and dual-fluorophore-labeled i-motif sequences. The short oligonucleotides are designed to bind with the i-motif sequences and immobilized on the AuNP surface via Au-S bond. At neutral pH, the dual fluorophores are separated, resulting in very low fluorescence resonance energy transfer (FRET) efficiency. At acidic pH, the i-motif strands fold into a quadruplex structure and leave the AuNP, bringing the dual fluorophores into close proximity, resulting in high FRET efficiency, which could be used as a signal for pH sensing. The nanoprobe possesses abilities of cellular transfection, enzymatic protection, fast response and quantitative pH detection. The in vitro and intracellular applications of the nanoprobe were demonstrated, which showed excellent response in the physiological pH range. Furthermore, our experimental results suggested that the nanoprobe showed excellent spatial and temporal resolution in living cells. We think that the ratiometric sensing strategy could potentially be applied to create a variety of new multicolor sensors for intracellular detection.

  5. Internalization and Subcellular Trafficking of Poly-l-lysine Dendrimers Are Impacted by the Site of Fluorophore Conjugation.

    Science.gov (United States)

    Avaritt, Brittany R; Swaan, Peter W

    2015-06-01

    Internalization and intracellular trafficking of dendrimer-drug conjugates play an important role in achieving successful drug delivery. In this study, we aimed to elucidate the endocytosis mechanisms and subcellular localization of poly-l-lysine (PLL) dendrimers in Caco-2 cells. We also investigated the impact of fluorophore conjugation on cytotoxicity, uptake, and transepithelial transport. Oregon green 514 (OG) was conjugated to PLL G3 at either the dendrimer periphery or the core. Chemical inhibitors of clathrin-, caveolin-, cholesterol-, and dynamin-mediated endocytosis pathways and macropinocytosis were employed to establish internalization mechanisms, while colocalization with subcellular markers was used to determine dendrimer trafficking. Cell viability, internalization, and uptake were all influenced by the site of fluorophore conjugation. Uptake was found to be highly dependent on cholesterol- and dynamin-mediated endocytosis as well as macropinocytosis. Dendrimers were trafficked to endosomes and lysosomes, and subcellular localization was impacted by the fluorophore conjugation site. The results of this study indicate that PLL dendrimers exploit multiple pathways for cellular entry, and internalization and trafficking can be impacted by conjugation. Therefore, design of dendrimer-drug conjugates requires careful consideration to achieve successful drug delivery.

  6. Red Emitting Phenyl-Polysiloxane Based Scintillators for Neutron Detection

    International Nuclear Information System (INIS)

    Dalla Palma, Matteo; Quaranta, Alberto; Marchi, Tommaso; Gramegna, Fabiana; Cinausero, Marco; Carturan, Sara; Collazuol, Gianmaria

    2013-06-01

    In this work, the performances of new red emitting phenyl- substituted polysiloxane based scintillators are described. Three dyes were dispersed in a phenyl-polysiloxane matrix in order to shift the scintillation wavelength towards the red part of the visible spectrum. PPO, Lumogen Violet (BASF) and Lumogen Red (BASF) were mixed to the starting resins with different wt. % and the analysis of the different samples was performed by means of fluorescence measurements. The scintillation yield to alpha particles at the different dye ratios was monitored by detecting either the full spectrum or the red part of the emitted light. Finally, thin red scintillators with selected compositions were coupled to Avalanche Photodiode sensors, which are usually characterized by higher efficiency in the red part of the spectrum. An increased light output of about 17% has been obtained comparing the red scintillators to standard blue emitting systems. Preliminary results on the detection of fast neutrons with the APD-red scintillator system are also presented. (authors)

  7. Imaging of Lymph Flow in Breast Cancer Patients after Microdose Administration of a Near-Infrared Fluorophore: Feasibility Study1

    Science.gov (United States)

    Sevick-Muraca, Eva M.; Sharma, Ruchi; Rasmussen, John C.; Marshall, Milton V.; Wendt, Juliet A.; Pham, Hoang Q.; Bonefas, Elizabeth; Houston, Jessica P.; Sampath, Lakshmi; Adams, Kristen E.; Blanchard, Darlene Kay; Fisher, Ronald E.; Chiang, Stephen B.; Elledge, Richard; Mawad, Michel E.

    2011-01-01

    Purpose To prospectively demonstrate the feasibility of using indocyanine green, a near-infrared (NIR) fluorophore at the minimum dose needed for noninvasive optical imaging of lymph nodes (LNs) in breast cancer patients undergoing sentinel lymph node mapping (SLNM). Materials and Methods Informed consent was obtained from 24 women (age range, 30–85 years) who received intradermal subcutaneous injections of 0.31–100 μg indocyanine green in the breast in this IRB-approved, HIPAA-compliant, dose escalation study to find the minimum microdose for imaging. The breast, axilla, and sternum were illuminated with NIR light and the fluorescence generated in the tissue was collected with an NIR-sensitive intensified charged-coupled device. Lymphoscintigraphy was also performed. Resected LNs were evaluated for the presence of radioactivity, blue dye accumulation, and fluorescence. The associations between the resected LNs that were fluorescent and (a) the time elapsed between NIR fluorophore administration and resection and (b) the dosage of NIR fluorophores were tested with the Spearman rank and Pearson product moment correlation tests, respectively. Results Lymph imaging consistently failed with indocyanine green microdosages between 0.31 and 0.77 μg. When indocyanine green dosages were 10 μg or higher, lymph drainage pathways from the injection site to LNs were imaged in eight of nine women; lymph propulsion was observed in seven of those eight. When propulsion in the breast and axilla regions was present, the mean apparent velocities ranged from 0.08 to 0.32 cm/sec, the time elapsed between “packets” of propelled fluid varied from 14 to 92 seconds. In patients who received 10 μg of indocyanine green or more, a weak negative correlation between the fluorescence status of resected LNs and the time between NIR fluorophore administration and LN resection was found. No statistical association was found between the fluorescence status of resected LNs and the dose of

  8. Azadioxatriangulenium: a long fluorescence lifetime fluorophore for large biomolecule binding assay

    International Nuclear Information System (INIS)

    Sørensen, Thomas Just; Thyrhaug, Erling; Szabelski, Mariusz; Gryczynski, Ignacy; Gryczynski, Zygmunt; Luchowski, Rafal; Laursen, Bo W

    2013-01-01

    Of the many optical bioassays available, sensing by fluorescence anisotropy has great advantages as it provides a sensitive, instrumentally simple, ratiometric method of detection. However, it is hampered by a severe limitation, as the emission lifetime of the label needs to be comparable to the correlation lifetime (tumbling time) of the biomolecule which is labelled. For proteins of moderate size this is on the order of 20–200 ns, which due to practical issues currently limits the choice of labels to the dansyl-type dyes and certain aromatic dyes. These have the significant drawback of UV/blue absorption and emission as well as an often significant solvent sensitivity. Here, we report the synthesis and characterization of a new fluorescent label for high molecular weight biomolecule assay based on the azadioxatriangulenium motif. The NHS ester of the long fluorescence lifetime, red-emitting fluorophore: azadioxatriangulenium (ADOTA-NHS) was conjugated to anti-rabbit Immunoglobulin G (antiIgG). The long fluorescence lifetime was exploited to determine the correlation time of the high molecular weight antibody and its complex with rabbit Immunoglobulin G (IgG) with steady-state fluorescence anisotropy and time-resolved methods: solution phase immuno-assay was performed following either steady-state or time-resolved fluorescence anisotropy. By performing a variable temperature experiment it was determined that the binding of the ligand resulted in an increase in correlation time of more than 75%, and an increase in the steady-state anisotropy of 18%. The results show that the triangulenium class of dyes can be used in anisotropy assay to detect binding events involving biomolecules of far larger size than what is possible with most other red-emitting organic dyes. (paper)

  9. Azadioxatriangulenium: a long fluorescence lifetime fluorophore for large biomolecule binding assay

    Science.gov (United States)

    Just Sørensen, Thomas; Thyrhaug, Erling; Szabelski, Mariusz; Luchowski, Rafal; Gryczynski, Ignacy; Gryczynski, Zygmunt; Laursen, Bo W.

    2013-06-01

    Of the many optical bioassays available, sensing by fluorescence anisotropy has great advantages as it provides a sensitive, instrumentally simple, ratiometric method of detection. However, it is hampered by a severe limitation, as the emission lifetime of the label needs to be comparable to the correlation lifetime (tumbling time) of the biomolecule which is labelled. For proteins of moderate size this is on the order of 20-200 ns, which due to practical issues currently limits the choice of labels to the dansyl-type dyes and certain aromatic dyes. These have the significant drawback of UV/blue absorption and emission as well as an often significant solvent sensitivity. Here, we report the synthesis and characterization of a new fluorescent label for high molecular weight biomolecule assay based on the azadioxatriangulenium motif. The NHS ester of the long fluorescence lifetime, red-emitting fluorophore: azadioxatriangulenium (ADOTA-NHS) was conjugated to anti-rabbit Immunoglobulin G (antiIgG). The long fluorescence lifetime was exploited to determine the correlation time of the high molecular weight antibody and its complex with rabbit Immunoglobulin G (IgG) with steady-state fluorescence anisotropy and time-resolved methods: solution phase immuno-assay was performed following either steady-state or time-resolved fluorescence anisotropy. By performing a variable temperature experiment it was determined that the binding of the ligand resulted in an increase in correlation time of more than 75%, and an increase in the steady-state anisotropy of 18%. The results show that the triangulenium class of dyes can be used in anisotropy assay to detect binding events involving biomolecules of far larger size than what is possible with most other red-emitting organic dyes.

  10. Azadioxatriangulenium (ADOTA+): A long fluorescence lifetime fluorophore for large biomolecule binding assay

    Science.gov (United States)

    Sørensen, Thomas Just; Thyrhaug, Erling; Szabelski, Mariusz; Luchowski, Rafal; Gryczynski, Ignacy; Gryczynski, Zygmunt; Laursen, Bo W.

    2013-01-01

    Of the many optical bioassays available, sensing by fluorescence anisotropy have great advantages as it provides a sensitive, instrumentally simple, ratiometric method of detection. However, it is hampered by a severe limitation as the emission lifetime of the label needs to be comparable to the correlation lifetime (tumbling time) of the biomolecule which is labelled. For proteins of moderate size this is in the order of 20–200 ns, which due to practical issues currently limits the choice of labels to the dansyl-type dyes and certain aromatics dyes. These have the significant drawback of UV/blue absorption and emission as well as an often significant solvent sensitivity. Here, we report the synthesis and characterization of a new fluorescent label for high molecular weight biomolecules assay based on the azadioxatriangulenium motif. The NHS ester of the long fluorescence lifetime, red emitting fluorophore: azadioxatriangulenium (ADOTA-NHS) was conjugated to anti-rabbit Immunoglobulin G (antiIgG). The long fluorescence lifetime was exploited to determine the correlation time of the high molecular weight antibody and its complex with rabbit Immuniglobulin G (IgG) with steady-state fluorescence anisotropy and time-resolved methods: solution phase immuno-assay was performed following either steady-state or time-resolved fluorescence anisotropy. By performing a variable temperature experiment it was determined that the binding of the ligand resulted in an increase in correlation time by more than 75 %, and a change in the steady-state anisotropy increase of 18%. The results show that the triangulenium class of dyes can be used in anisotropy assay for detecting binding events involving biomolecules of far larger size than what is possible with the other red emitting organic dyes. PMID:24058730

  11. 2-(4-Methylpiperazin-1-yl-4-phenyl-6-(thiophen-2-yl-pyridine-3-carbonitrile

    Directory of Open Access Journals (Sweden)

    Nawal Mishriky

    2013-02-01

    Full Text Available 2-(4-Methylpiperazin-1-yl-4-phenyl-6-(thiophen-2-yl-pyridine-3-carbonitrile (4 was synthesized via nucleophilic substitution reaction of 1-methylpiperazine with 2-bromo analogue 3. The latter was obtained through bromination (Br2/AcOH of 2-[3-oxo-1-phenyl-3-(thiophen-2-ylpropyl]malononitrile (2.

  12. Ideal gas thermodynamic properties for the phenyl, phenoxy, and o-biphenyl radicals

    Science.gov (United States)

    Burcat, A.; Zeleznik, F. J.; Mcbride, B. J.

    1985-01-01

    Ideal gas thermodynamic properties of the phenyl and o-biphenyl radicals, their deuterated analogs and the phenoxy radical were calculated to 5000 K using estimated vibrational frequencies and structures. The ideal gas thermodynamic properties of benzene, biphenyl, their deuterated analogs and phenyl were also calculated.

  13. 40 CFR 721.2577 - Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Copper complex of (substituted... Copper complex of (substituted sulfonaphthyl azo substituted phenyl) disulfonaphthyl azo, amine salt... substances identified generically as copper complex of (substituted sulfonaphthyl azo substituted phenyl...

  14. Positron Lifetime Study of the Transition from Glassy to Normal Liquid State for Two Phenyl Ethers

    DEFF Research Database (Denmark)

    Pethrick, R. A.; Jacobsen, F. M.; Mogensen, O. E.

    1980-01-01

    Positron lifetime measurements are reported as a function of temperature for bis[m-(m-phenoxyphenoxy)phenyl] ether and m-phenoxyphenyl-m-(m-phenoxyphenoxy)phenyl ether. The decay curves were analysed in terms of three lifetime components; two short lifetimes of typically 200 and 500 ps associated...

  15. Synthesis, characterization and crystal structure of 6-Chloro-4,4‧-dimethyl-2,2‧-bipyridine and 4,4‧-Dimethyl 2,2‧-bipyridine N-Oxide

    Science.gov (United States)

    Conterosito, Eleonora; Magistris, Claudio; Barolo, Claudia; Croce, Gianluca; Milanesio, Marco

    2016-03-01

    The synthesis, the NMR characterization and the crystal structure of 6-Chloro 4,4‧-dimethyl 2,2‧-bipyridine and of the reaction intermediate 4,4‧-Dimethyl 2,2‧-bipyridine N-Oxide are here reported. The target compound crystallizes in the orthorhombic system while the intermediate is monoclinic. In both structures, the molecules are linked by weak interactions. The structure of the reaction intermediate N-oxide is characterized by a dihedral angle between the two phenyl rings of 161.77° while the other is almost planar with a dihedral angle of 179.15°. The crystal packing was investigated, also with the aid of Hirshfeld surface analysis. In the N-oxide reaction intermediate the packing is governed by CH-O interactions, while in the product the packing is simply driven by minimizing the voids and thus maximizing the density, with a prevalence of H•••H and C•••H contacts, as indicated by fingerprint decomposition analysis.

  16. Synthesis, characterization and corrosion inhibition properties of benzamide-2-chloro-4-nitrobenzoic acid and anthranilic acid-2-chloro-4-nitrobenzoic acid for mild steel corrosion in acidic medium

    Science.gov (United States)

    Pandey, Archana; Verma, Chandrabhan; Singh, B.; Ebenso, Eno E.

    2018-03-01

    The present study deals with the synthesis of two new compounds namely, benzamide - 2-chloro-4-nitrobenzoic acid (BENCNBA) and anthranilic acid-2-chloro-4-nitrobenzoic acid (AACNBA) using solid phase reactions. The phase diagram studies revealed that formation of the investigated compounds occurs in 1:1 molar ratio. The synthesized compounds were characterized using several spectral techniques such as FT-IR, 1H and 13C NMR, UV-Vis, powder X-ray diffraction (PXRD). Single crystal XRD (SCXRD) study showed that both BENCNBA and AACNBA compounds crystallize in triclinic crystal system with P-1 space group. Further, the presence of intermolecular hydrogen bonding between the constituent components was also supported by single crystal X-ray diffraction (SCXRD) method. Heat of mixing, entropy of fusion, roughness parameter, interfacial energy and excess thermodynamic functions have also been computed using the enthalpy of fusion values derived from differential scanning calorimeter (DSC) study. The inhibition effect of BENCNBA and AACNBA on the mild steel corrosion in hydrochloric acid solution was tested using electrochemical methods. Electrochemical impedance spectroscopy (EIS) study revealed that both BENCNBA and AACNBA behaved as interface corrosion inhibitors and showed maximum inhibition efficiencies of 95.71% and 96.42%, respectively at 400 ppm (1.23 × 10-3 M) concentration. Potentiodynamic polarization (PDP) measurements suggested that BENCNBA and AACNBA acted as mixed type corrosion inhibitors. EIS and PDP results showed that BENCNBA and AACNBA act as efficient corrosion inhibitors for mild steel and their inhibition efficiencies enhances on increasing their concentrations.

  17. Inhibiting the corrosion of MNZh 5-1 alloy in neutral solutions of 5-chloro-1,2,3-benzotrialzol

    Science.gov (United States)

    Kuznetsov, Yu. I.; Agafonkina, M. O.; Andreeva, N. P.; Arkhipushkin, I. A.; Kazansky, L. P.

    2017-11-01

    The adsorption and protective properties of 5-chloro-1,2,3-benzotriazol (5-chloro-BTA) are studied in relation to MNZh 5-1 alloy in a chloride borate buffer solution with pH 7.4. It is shown that this inhibitor can stabilize the passive state of the alloy at a concentration of 0.12 mmol/g. The adsorption of 5-chloro-BTA on a surface of MNZh 5-1 alloy is polymolecular; the free energy of adsorption is about 80 kJ/mol. The advantages of adsorption and protective properties of 5-chloro-BTA compared to BTA on both MNZh 5-1 alloy and the metals contained in the alloy (Ni, Cu) are shown. XPS data indicate a 5-chloro-BTA monolayer formed on the surface of the alloy. This monolayer was composed of inhibitor molecules, which are normally oriented toward a surface and are not removed during ultrasonic washing of the electrode.

  18. SYNTHESIS OF ALLYL PHENYL ETHER AND CLAISEN REARRANGEMENT

    Directory of Open Access Journals (Sweden)

    Gagik Torosyan

    2011-12-01

    Full Text Available It has been established the possibility for phenol allylation on natural zeolites and them analogs. Here is demonstrated the synthesis of allyl phenol, which has wide industrial applications. The offered method in comparison with the traditional methods has more advantages – higher selectivity, smaller material and power resources consumption. It has been obtained the mixture of allylating phenols (30% in general with allyl phenyl ether (1 with 80% yields. At 600 K is obtained allylphenyl ether, at 700 K beginning the formation of allyl phenols, which is the result of direct C-allylation of the aromatic ring. It has been investigated the possibility of Claisen rearrangement in the same conditions. All of that are established by gas-liquid chromatography and liquid chromatography data.

  19. 1-Methyl-5-nitro-3-phenyl-1H-indazole

    Directory of Open Access Journals (Sweden)

    Mohammed Naas

    2016-06-01

    Full Text Available The title compound, C14H11N3O2, crystallizes with two molecules in the asymmetric unit. The indazole ring system and the nitro group are nearly coplanar, with the largest deviations from the mean plane being 0.070 (4 Å in one molecule and 0.022 (3 Å in the second. The dihedral angle between the mean plane through the phenyl ring and the mean plane of the indazole ring system is of 23.24 (18° in the first molecule and 26.87 (18° in the second. In the crystal, molecules are linked by two C—H...O hydrogen bonds, forming linear zigzag tapes running along the c-axis direction, and by π–π stacking of molecules along the b axis, generating a three-dimensional structure.

  20. Updated European Union Risk Assessment Report of Alkanes, C10-13, Chloro

    OpenAIRE

    2008-01-01

    A risk assessment of alkanes, C10-13, chloro (short-chain chlorinated paraffins or SCCPs) produced in accordance with Council Regulation (EEC) 793/93 was published in October 1999 . Subsequent marketing and use restrictions for two uses (metal working and use for fat liquoring of leather) have come into force in the European Union through Directive 2002/45/EC . This Directive also states that all remaining uses of short-chain chlorinated paraffins will be reviewed by the European Commission ...

  1. Purification and characterization of the 3-chloro-4-hydroxy-phenylacetate reductive dehalogenase of Desulfitobacterium hafniense

    DEFF Research Database (Denmark)

    Christensen, Nina; Ahring, Birgitte Kiær; Wohlfarth, Gert

    1998-01-01

    The membrane-bound 3-chloro-4-hydroxyphenylacetate (Cl-OHPA) reductive dehalogenase from the chlorophenol- educing anaerobe Desulfitobacterium hafniense was purified 11.3-fold to apparent homogeneity in the presence of the detergent CHAPS. The purified dehalogenase catalyzed the reductive...... dechlorination of Cl-OHPA to 4-hydroxyphenylacetate with reduced methyl viologen as the electron donor at a specific activity of 103.2 nkat/mg protein. SDS-PAGErevealed a single protein band with an apparent molecular mass of 46.5 kDa. The enzyme contained 0.68±0.2 mol corrinoid, 12.0±0.7 mol iron, and 13...

  2. 40 CFR 721.1000 - Benzenamine, 3-chloro-2,6-dinitro-N,N-dipropyl-4-(tri-fluoro-methyl)-.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Benzenamine, 3-chloro-2,6-dinitro-N,N-dipropyl-4-(tri-fluoro-methyl)-. 721.1000 Section 721.1000 Protection of Environment ENVIRONMENTAL... Significant New Uses for Specific Chemical Substances § 721.1000 Benzenamine, 3-chloro-2,6-dinitro-N,N...

  3. Synthesis of 9H-indeno [1, 2-b] pyrazine and 11H-indeno [1, 2-b] quinoxaline derivatives in one-step reaction from 2-bromo-4-chloro-1-indanone

    OpenAIRE

    Jasouri, S.; Khalafy, J.; Badali, M.; Prager, R.H.

    2011-01-01

    The reaction of 2-bromo-4-chloro-1-indanone with 2,3-diaminomaleonitrile, benzene-1,2-diamine and 4-methylbenzene-1,2-diamine in glacial acetic acid gave 8-chloro-9H-indeno[1,2-b]pyrazine-2,3-dicarbonitrile, 1-chloro-11H-indeno[1,2-b]quinoxa-line and 1-chloro-7-methyl-11H-indeno[1,2-b]quinoxaline, respectively, in good yield.

  4. Identification of α-Chloro-2,2',4,4',6,6'-Hexanitrobibenzyl as an Impurity in Hexanitrostilbene

    Science.gov (United States)

    Bellamy, A. J.

    2010-01-01

    The final intermediate in the Shipp synthesis of 2,2‧,4,4‧,6,6‧-hexanitrostilbene (HNS) from TNT, α-chloro-2,2‧,4,4‧,6,6‧-hexanitrobibenzyl, has been extracted and characterized by nuclear magnetic resonance (NMR) spectroscopy, chlorine elemental analysis, and high-performance liquid chromatography (HPLC). It has also been shown that digestion in NMP of HNS containing α-chlorohexanitrobibenzyl generates another chlorine-containing by-product, 2-chloro-2‧,4,4‧,6,6‧-pentanitrostilbene. This too has been characterized by NMR spectroscopy, chlorine elemental analysis, and HPLC.

  5. 3,5-Bis(4-methoxyphenyl-1-phenyl-4,5-dihydro-1H-pyrazole

    Directory of Open Access Journals (Sweden)

    Zeliha Baktır

    2011-02-01

    Full Text Available In the title compound, C23H22N2O2, the central pyrazole ring is nearly planar (r.m.s. deviation = 0.046 Å and it makes a dihedral angle of 18.5 (2° with the phenyl ring. The dihedral angles between the phenyl and the two methoxy-substituted phenyl rings are 26.2 (2 and 80.6 (2°. The crystal structure is stabilized by C—H...π stacking interactions and weak π–π interactions [centriod–centroid distance = 3.891 (2 Å].

  6. Metabolism of chinoform(5-chloro-7-iodo-8-quinolinol)-14C in dog

    International Nuclear Information System (INIS)

    Urakubo, Goro; Kido, Yasumasa; Ikebuchi, Hideharu; Nagamatsu, Kunisuke

    1975-01-01

    Chinoform (6-chloro-7-iodo-8-quinolinol)- 14 C (302.4μCi/83 mg) packed in a capsule was given orally to a dog weighing 10.5 kg, and the urine and feces were collected for 5 days after dosing. Excretion of a large portion of the radioactivity in urine and feces was observed on the 1st day and 3rd day after dosing. The total radioactivity in both excreta in 5 days was about 70% of dose. The urine was used for the study of metabolites. The urine was extracted with a mixture of benzene and pyridine (9:1), and an organic layer and an aqueous layer were obtained. Intact chinoform and 5-chloro-8-quinolinol (a deiodinated product of chinoform) were identified in the organic layer by radiochromatography and by an isotope dilution method. From the water layer of urine, glucuronides of chinoform and the deiodinated product, and sulfate of chinoform were identified as the metabolites. (author)

  7. Metabolism of chinoform(5-chloro-7-iodo-8-quinolinol)-/sup 14/C in dog

    Energy Technology Data Exchange (ETDEWEB)

    Urakubo, G; Kido, y; Ikebuchi, H; Nagamatsu, K [National Inst. of Hygienic Sciences, Tokyo (Japan)

    1975-07-01

    Chinoform (6-chloro-7-iodo-8-quinolinol)-/sup 14/C (302.4..mu..Ci/83 mg) packed in a capsule was given orally to a dog weighing 10.5 kg, and the urine and feces were collected for 5 days after dosing. Excretion of a large portion of the radioactivity in urine and feces was observed on the 1st day and 3rd day after dosing. The total radioactivity in both excreta in 5 days was about 70% of dose. The urine was used for the study of metabolites. The urine was extracted with a mixture of benzene and pyridine (9:1), and an organic layer and an aqueous layer were obtained. Intact chinoform and 5-chloro-8-quinolinol (a deiodinated product of chinoform) were identified in the organic layer by radiochromatography and by an isotope dilution method. From the water layer of urine, glucuronides of chinoform and the deiodinated product, and sulfate of chinoform were identified as the metabolites.

  8. Radiolytic generation of chloro-organic compounds in transuranic and low-level radioactive waste

    International Nuclear Information System (INIS)

    Reed, D.T.; Armstrong, S.C.; Krause, T.R.

    1993-01-01

    The radiolytic degradation of chloro-plastics is being investigated to evaluate the formation of chlorinated volatile organic compounds in radioactive waste. These chlorinated VOCs, when their subsequent migration in the geosphere is considered, are potential sources of ground-water contamination. This contamination is an important consideration for transuranic waste repositories being proposed for the Waste Isolation Pilot Plant project and the several additional low-level radioactive waste sites being considered throughout the United States. The production of chlorinated volatile organic compounds due to the interaction of ionizing radiation with chloro-plastic materials has been well-established in both this work and past studies. This occurs as a result of gamma, beta, and alpha particle interactions with the plastic material. The assemblage of organic compounds generated depends on the type of plastic material, the type of ionizing radiation, the gaseous environment present and the irradiation temperature. In the authors' experiments, gas generation data were obtained by mounting representative plastics near (3 mm) an alpha particle source (Am-241 foil). This assembly was placed in an irradiation vessel which contained air, nitrogen, or a hydrogen/carbon dioxide mixture, at near-atmospheric pressures, to simulate the range of atmospheres likely to be encountered in the subsurface. The gas phase in the vessels are periodically sampled for net gas production. The gas phase concentrations are monitored over time to determine trends and calculate the radiolytic yield for the various gaseous products

  9. Enhanced bioreduction synthesis of ethyl (R)-4-chloro-3-hydroybutanoate by alkalic salt pretreatment.

    Science.gov (United States)

    Chong, Ganggang; Di, Junhua; Ma, Cuiluan; Wang, Dajing; Wang, Chu; Wang, Lingling; Zhang, Pengqi; Zhu, Jun; He, Yucai

    2018-08-01

    In this study, biomass-hydrolysate was used for enhancing the bioreduction of ethyl 4-chloro-3-oxobutanoate (COBE). Firstly, dilute alkalic salt pretreatment was attempted to pretreat bamboo shoot shell (BSS). It was found that enzymatic in situ hydrolysis of 20-50 g/L BSS pretreated with dilute alkalic salts (0.4% Na 2 CO 3 , 0.032% Na 2 S) at 7.5% sulfidity by autoclaving at 110 °C for 40 min gave sugar yields at 59.9%-73.5%. Moreover, linear relationships were corrected on solid recovery-total delignification-sugar yield. In BSS-hydrolysates, xylose and glucose could promote the reductase activity of recombinant E. coli CCZU-A13. Compared with glucose, hydrolysate could increase the reductase activity by 1.35-folds. Furthermore, the cyclohexane-hydrolysate (10:90, v/v) biphasic media containing ethylene diamine tetraacetic acid (EDTA, 40 mM) and l-glutamine (150 mM) was built for the effective biosynthesis of ethyl (R)-4-chloro-3-hydroxybutanoate [(R)-CHBE] (94.6% yield) from 500 mM COBE. In conclusion, this strategy has high potential for the effective biosynthesis of (R)-CHBE (>99% e.e.). Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Activatable Optical Imaging with a Silica-Rhodamine Based Near Infrared (SiR700) Fluorophore: A comparison with cyanine based dyes

    Science.gov (United States)

    McCann, Thomas E.; Kosaka, Nobuyuki; Koide, Yuichiro; Mitsunaga, Makoto; Choyke, Peter L.; Nagano, Tetsuo; Urano, Yasuteru; Kobayashi, Hisataka

    2011-01-01

    Optical imaging is emerging as an important tool to visualize tumors. However, there are many potential choices among the available fluorophores. Optical imaging probes that emit in the visible range can image superficial tumors with high quantum yields, however, if deeper imaging is needed then near infrared (NIR) fluorophores are necessary. Most commercially available NIR fluorophores are cyanine based and are prone to non-specific binding and relatively limited photostability. Silica-containing rhodamine (SiR) fluorophores represent a new class of NIR fluorophores, which permit photoactivation via H-dimer formation as well as demonstrate improved photostability. This permits higher tumor-to-background ratios (TBRs) to be achieved over longer periods of time. Here, we compared an avidin conjugated with SiR700 (Av-SiR700) to similar compounds based on cyanine dyes (Av-Cy5.5 and Av-Alexa Fluor 680) in a mouse tumor model of ovarian cancer metastasis. We found that the Av-SiR700 probe demonstrated superior quenching enabling activation after binding-internalization to the target cell. As a result, Av-SiR700 had higher TBRs compared to Av-Cy5.5, and better biostability compared to Av-Alexa Fluor 680. PMID:22034863

  11. Reversible switching of fluorophore property based on intrinsic conformational transition of adenylate kinase during its catalytic cycle.

    Science.gov (United States)

    Fujii, Akira; Hirota, Shun; Matsuo, Takashi

    2013-07-17

    Adenylate kinase shows a conformational transition (OPEN and CLOSED forms) during substrate binding and product release to mediate the phosphoryl transfer between ADP and ATP/AMP. The protein motional characteristics will be useful to construct switching systems of fluorophore properties caused by the catalytic cycle of the enzyme. This paper demonstrates in situ reversible switching of a fluorophore property driven by the conformational transition of the enzyme. The pyrene-conjugated mutant adenylate kinase is able to switch the monomer/excimer emission property of pyrene on addition of ADP or P(1)P(5)-di(adenosine-5')pentaphosphate (Ap5A, a transition state analog). The observation under the dilute condition (~0.1 μM) indicates that the emission spectral change was caused by the motion of a protein molecule and not led by protein-protein interactions through π-π stacking of pyrene rings. The switching can be reversibly conducted by using hexokinase-coupling reaction. The fashion of the changes in emission intensities at various ligand concentrations is different between ADP, Mg(2+)-bound ADP, and Mg(2+)-bound Ap5A. The emission property switching is repeatable by a sequential addition of a substrate in a one-pot process. It is proposed that the property of a synthetic molecule on the enzyme surface is switchable in response to the catalytic cycle of adenylate kinase.

  12. The Effect of a Fluorophore Photo-Physics on the Lipid Vesicle Diffusion Coefficient Studied by Fluorescence Correlation Spectroscopy.

    Science.gov (United States)

    Drabik, Dominik; Przybyło, Magda; Sikorski, Aleksander; Langner, Marek

    2016-03-01

    Fluorescence Correlation Spectroscopy (FCS) is a technique, which allows determination of the diffusion coefficient and concentration of fluorescent objects suspended in the solution. The measured parameter is the fluctuation of the fluorescence signal emitted by diffusing molecules. When 100 nm DOPC vesicles labeled with various fluorescent dyes (Fluorescein-PE, NBD-PE, Atto488 DOPE or βBodipy FL) were measured, different values of diffusion coefficients have been obtained. These diffusion coefficients were different from the expected values measured using the dynamic light scattering method (DLS). The FCS was initially developed for solutions containing small fluorescent molecules therefore the observed inconsistency may result from the nature of vesicle suspension itself. The duration of the fluorescence signal may depend on the following factors: the exposure time of the labeled object to the excitation beam, the photo-physical properties (e.g., stability) of a fluorophore, the theoretical model used for the calculations of the diffusion coefficient and optical properties of the vesicle suspension. The diffusion coefficients determined for differently labeled liposomes show that its dependence on vesicle size and quantity of fluorescent probed used for labeling was significant demonstrating that the fluorescence properties of the fluorophore itself (bleaching and/or blinking) were critical factors for a correct outcome of FCS experiment. The new, based on combined FCS and DLS measurements, method for the determination of the focal volume prove itself to be useful for the evaluation of a fluorescence dye with respect to its applicability for FCS experiment.

  13. Exploring selectivity requirements for COX-2 versus COX-1 binding of 2-(5-phenyl-pyrazol-1-yl)-5-methanesulfonylpyridines using topological and physico-chemical parameters.

    Science.gov (United States)

    Chakraborty, Santanu; Sengupta, Chandana; Roy, Kunal

    2005-04-01

    Considering the current need for development of selective cyclooxygenase-2 (COX-2) inhibitors, an attempt has been made to explore physico-chemical requirements of 2-(5-phenyl-pyrazol-1-yl)-5-methanesulfonylpyridines for binding with COX-1 and COX-2 enzyme subtypes and also to explore the selectivity requirements. In this study, E-states of different common atoms of the molecules (calculated according to Kier & Hall), first order valence connectivity and physicochemical parameters (hydrophobicity pi, Hammett sigma and molar refractivity MR of different ring substituents) were used as independent variables along with suitable dummy parameters in the stepwise regression method. The best equation describing COX-1 binding affinity [n = 25, Q2 = 0.606, R(a)2 = 0.702, R2 = 0.752, R = 0.867, s = 0.447, F = 15.2 (df 4, 20)] suggests that the COX-1 binding affinity increases in the presence of a halogen substituent at R1 position and a p-alkoxy or p-methylthio substituent at R2 position. Furthermore, a difluoromethyl group is preferred over a trifluoromethyl group at R position for the COX-1 binding. The best equation describing COX-2 binding affinity [n = 32, Q2 = 0.622, R(a)2= 0.692, R2 = 0.732, R = 0.856, s = 0.265, F = 18.4 (df 4, 27)] shows that the COX-2 binding affinity increases with the presence of a halogen substituent at R1 position and increase of size of R2 substituents. However, it decreases in case of simultaneous presence of 3-chloro and 4-methoxy groups on the phenyl nucleus and in the presence of highly lipophilic R2 substituents. The best selectivity relation [n = 25, Q2 = 0.455, R(a)2 = 0.605, R2 = 0.670, R = 0.819, s = 0.423, F = 10.2 (df 4, 20)] suggests that the COX-2 selectivity decreases in the presence of p-alkoxy group and electron-withdrawing para substituents at R2 position. Again, a trifluoro group is conductive for the selectivity instead of a difluoromethyl group at R position. Furthermore, branching may also play significant role in

  14. trans-2-Phenyl-4-thiophenoxy-3,4-dihydro-2H-1-benzothiopyran

    Directory of Open Access Journals (Sweden)

    Rammohan Pal

    2011-02-01

    Full Text Available Iodine-catalyzed cyclocondensation of cinnamaldehyde and thiophenol yields rapidly trans-2-phenyl-4-thiophenoxy-3,4-dihydro-2H-1-benzothiopyran in excellent yield with very high diastereoselectivity.

  15. Enzymatic synthesis of S-phenyl-L-cysteine from keratin hydrolysis industries wastewater with tryptophan synthase.

    Science.gov (United States)

    Xu, Lisheng; Wang, Zhiyuan; Mao, Pingting; Liu, Junzhong; Zhang, Hongjuan; Liu, Qian; Jiao, Qing-Cai

    2013-04-01

    An economical method for production of S-phenyl-L-cysteine from keratin acid hydrolysis wastewater (KHW) containing L-serine was developed by recombinant tryptophan synthase. This study provides us with an alternative KHW utilization strategy to synthesize S-phenyl-L-cysteine. Tryptophan synthase could efficiently convert L-serine contained in KHW to S-phenyl-L-cysteine at pH 9.0, 40°C and Trion X-100 of 0.02%. In a scale up study, L-serine conversion rate reach 97.1% with a final S-phenyl-L-cysteine concentration of 38.6 g l(-1). Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Quantitative time domain analysis of lifetime-based Förster resonant energy transfer measurements with fluorescent proteins: Static random isotropic fluorophore orientation distributions

    DEFF Research Database (Denmark)

    Alexandrov, Yuriy; Nikolic, Dino Solar; Dunsby, Christopher

    2018-01-01

    Förster resonant energy transfer (FRET) measurements are widely used to obtain information about molecular interactions and conformations through the dependence of FRET efficiency on the proximity of donor and acceptor fluorophores. Fluorescence lifetime measurements can provide quantitative...... into new software for fitting donor emission decay profiles. Calculated FRET parameters, including molar population fractions, are compared for the analysis of simulated and experimental FRET data under the assumption of static and dynamic fluorophores and the intermediate regimes between fully dynamic...... analysis of FRET efficiency and interacting population fraction. Many FRET experiments exploit the highly specific labelling of genetically expressed fluorescent proteins, applicable in live cells and organisms. Unfortunately, the typical assumption of fast randomization of fluorophore orientations...

  17. Exciton Transport Simulations in Phenyl Cored Thiophene Dendrimers

    Science.gov (United States)

    Kim, Kwiseon; Erkan Kose, Muhammet; Graf, Peter; Kopidakis, Nikos; Rumbles, Garry; Shaheen, Sean E.

    2009-03-01

    Phenyl cored 3-arm and 4-arm thiophene dendrimers are promising materials for use in photovoltaic devices. It is important to understand the energy transfer mechanisms in these molecules to guide the synthesis of novel dendrimers with improved efficiency. A method is developed to estimate the exciton diffusion lengths for the dendrimers and similar chromophores in amorphous films. The approach exploits Fermi's Golden Rule to estimate the energy transfer rates for an ensemble of bimolecular complexes in random orientations. Using Poisson's equation to evaluate Coulomb integrals led to efficient calculation of excitonic couplings between the transition densities. Monte-Carlo simulations revealed the dynamics of energy transport in the dendrimers. Experimental exciton diffusion lengths of the dendrimers range 10 ˜ 20 nm, increasing with the size of the dendrimer. Simulated diffusion lengths correlate well with experiments. The chemical structure of the chromophore, the shape of the transition densities and the exciton lifetime are found to be the most important factors that determine the exciton diffusion length in amorphous films.

  18. Extraction studies on rare earths using dinonyl phenyl phosphoric acid

    International Nuclear Information System (INIS)

    Anitha, M.; Singh, D.K.; Kotekar, M.K.; Vijayalakshmi, R.; Singh, H.

    2011-01-01

    Rare earths are widely used in phosphor materials, magnetic substances, alloys, catalyst, lasers, superconductors, solid oxide fuel cells and in nuclear applications. The high value of these elements depends on their effective separation into high purity compounds. The separation into individual rare earths is very difficult to achieve, due to the very low separation factors between two adjacent rare earths arising due to similar chemical properties. Taking the advantage of variation in basicity, the separation is generally accomplished by solvent extraction or ion exchange. There are several references on the separation of rare earth in different media employing various types of extractants such as 2-ethylhexyl 2-ethyhexylphosphonic acid (EHEHPA) and di-2-ethyl hexyl phosphoric acid (D2EHPA) which have been widely used for the separation and purification of rare earths. Dinonyl phenyl phosphoric acid (DNPPA) is an organo phosphorus extractant (pKa = 2.54) and is an aromatic analogue of D2EHPA, which extracts metal ion by cation exchange mechanism. DNPPA was explored to recover rare earths from phosphate media such as wet process phosphoric acid and merchant grade acid. However, there is no information available in literature on DNPPA for RE extraction from chloride medium. Therefore, an attempt has been made in the present study to investigate the feasibility of using DNPPA for extraction of La(III), Dy(III) and Y(III) from chloride medium

  19. Growth and characterization of new nonlinear optical 1-phenyl-3-(4-dimethylamino phenyl) prop-2-en-1-one (PDAC) single crystals

    Science.gov (United States)

    Ravindraswami, K.; Janardhana, K.; Gowda, Jayaprakash; Moolya, B. Narayana

    2018-04-01

    Non linear optical 1-phenyl-3-(4-dimethylamino phenyl) prop-2-en-1-one (PDAC) was synthesized using Claisen - Schmidt condensation method and studied for optical nonlinearity with an emphasis on structure-property relationship. The structural confirmation studies were carried out using 1H-NMR, FT-IR and single crystal XRD techniques. The nonlinear absorption and nonlinear refraction parameters in z-scan with nano second laser pulses were obtained by measuring the profile of propagated beam through the samples. The real and imaginary parts of third-order bulk susceptibility χ(3) were evaluated. Thermo gravimetric analysis is carried out to investigate the thermal stability.

  20. Theoretical investigation of tautomeric equilibrium in ortho-hydroxy phenyl Schiff bases

    Science.gov (United States)

    Kluba, M.; Lipkowski, P.; Filarowski, A.

    2008-10-01

    This Letter presents a study of the tautomeric equilibrium in ortho-hydroxy phenyl Schiff bases. The influence of substitution and solvent (simulated by the self-consistent reaction field model, SCRF) on the energy barrier of the transition state and on proton transfer is investigated. Dependencies of the HOMA and HOSE aromaticity indices on the molecular, transition state, and proton transfer forms were obtained. The state of chelate chain and phenyl ring aromaticity depending on the tautomeric equilibrium is studied.

  1. EXPOSURE-DISEASE CONTINUUM FOR 2-CHLORO-2'-DEOXYADENOSINE (2CDA), A PROTOTYPE OCULAR TERATOGEN. 1. DOSE-RESPONSE ANALYSIS

    Science.gov (United States)

    Treatment of pregnant mice with 2-chloro-2'-deoxyadenosine (2CdA) on day 8 of gestation induces coloboma, microphthalmia and anophthalmia through a mechanism coupled to the effects of the p53 tumor suppressor gene (Wubah et al.'96). The present study defines the dosimetry for 2Cd...

  2. A facile one-pot synthesis of (Z-α-chloro-α,β-unsaturated esters from alcohols

    Directory of Open Access Journals (Sweden)

    U. Karama

    2017-05-01

    Full Text Available Treatment of N-Chlorosuccinimide with (ethoxycarbonylmethylene-triphenylphosphorane followed by oxidation of alcohol using DMSO/SO3.Pyridine complex as a mild oxidant and trapping of the aldehydes constitutes a stereoselective single flask procedure for the preparation of Z-configured α-chloro-α,β-unsaturated esters.

  3. An Efficient Synthesis of 1-Alkyl-2-phenyl-4-quinolones from 2-Halobenzoic Acids

    International Nuclear Information System (INIS)

    Song, Yoon Ju; Choi, Jin Sun; Lee, Jae In

    2013-01-01

    The present method offers an efficient synthesis of 1-alkyl-2-phenyl-4-quinolones from 2-haloben-zoic acids. It has the advantages with respect to (i) synthesis of 2 equiv of alkynones 5 from 1 equiv of 4,6-pyrimidyl di(2-halobenzoates) 3, (ii) synthesis of versatile 1-alkyl-2-phenyl-4-quinolones in high overall yields, and (iii) use of readily available and cheap starting materials. Therefore, this method could be utilized as a practical synthesis of 1-alkyl-2-phenyl-4-quinolones. Several methods have been developed to synthesize 1-alkyl-2-phenyl-4-quinolones from 2'-substituted acetophenones, anilines, and 2-halobenzoyl chlorides as starting materials. The reaction of N-methylisatoic anhydride with the lithium enolate of an 4'-methoxyacetophenone afforded the 1-methyl-2-phenyl-4-quinolone in a short sequence, but the yield was low. N-(2-Acetylphenyl)benzamides, prepared by Friedel-Crafts acylation of N-phenyl benzamides with acetyl chloride or benzoylation of 2'-aminoacetophenones with benzoyl chlorides,8 were cyclized with potassium t-butoxide to yield 2-aryl-4-quinolones, which were further alkylated with alkyl iodides to give 1-alkyl-2-aryl-4-quinolones

  4. An Efficient Synthesis of 1-Alkyl-2-phenyl-4-quinolones from 2-Halobenzoic Acids

    Energy Technology Data Exchange (ETDEWEB)

    Song, Yoon Ju; Choi, Jin Sun; Lee, Jae In [Duksung Women' s Univ., Seoul (Korea, Republic of)

    2013-10-15

    The present method offers an efficient synthesis of 1-alkyl-2-phenyl-4-quinolones from 2-haloben-zoic acids. It has the advantages with respect to (i) synthesis of 2 equiv of alkynones 5 from 1 equiv of 4,6-pyrimidyl di(2-halobenzoates) 3, (ii) synthesis of versatile 1-alkyl-2-phenyl-4-quinolones in high overall yields, and (iii) use of readily available and cheap starting materials. Therefore, this method could be utilized as a practical synthesis of 1-alkyl-2-phenyl-4-quinolones. Several methods have been developed to synthesize 1-alkyl-2-phenyl-4-quinolones from 2'-substituted acetophenones, anilines, and 2-halobenzoyl chlorides as starting materials. The reaction of N-methylisatoic anhydride with the lithium enolate of an 4'-methoxyacetophenone afforded the 1-methyl-2-phenyl-4-quinolone in a short sequence, but the yield was low. N-(2-Acetylphenyl)benzamides, prepared by Friedel-Crafts acylation of N-phenyl benzamides with acetyl chloride or benzoylation of 2'-aminoacetophenones with benzoyl chlorides,8 were cyclized with potassium t-butoxide to yield 2-aryl-4-quinolones, which were further alkylated with alkyl iodides to give 1-alkyl-2-aryl-4-quinolones.

  5. Spectral behavior and photophysical parameters of (2Z)-3-[4-(dimethylamino) phenyl]-2-(4-fluorophenyl) prop-2-ene-nitrile (DPF) in different media

    Energy Technology Data Exchange (ETDEWEB)

    Pannipara, Mehboobali [Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Asiri, Abdullah M. [Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Center of Excellence for Advanced Materials Research, King Abdulaziz University, Jeddah 21589, P.O. Box 80203 (Saudi Arabia); Alamry, Khalid A. [Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Salem, Ibrahim A. [Department of Chemistry, Faculty of Science, Tanta University, 31527 Tanta (Egypt); El-Daly, Samy A., E-mail: samyeldaly@yahoo.com [Department of Chemistry, Faculty of Science, King Abdulaziz University, P.O. Box 80203, Jeddah 21589 (Saudi Arabia); Department of Chemistry, Faculty of Science, Tanta University, 31527 Tanta (Egypt)

    2015-01-15

    A new fluorophore, (2Z)-3-[4-(dimethylamino) phenyl]-2-(4-fluorophenyl) prop-2-ene-nitrile (DPF), was synthesized by knoevenagel condensation of 4-(dimethylamino) benzaldehyde and 4-fluorobenzyl cyanide in ethanol using NaOH as base. The electronic absorption and emission characteristic of DPF were studied in different solvents. The X-ray crystallographic structure of DPF was also investigated. DPF exhibits a red-shift in its emission spectrum as solvent polarity increases, indicating a large change in the dipole moment of dye molecule upon excitation due to intramolecular charge transfer in excited DPF{sup ⁎}. The fluorescence quantum yield depends strongly on the properties of the solvents, which was attributed to positive and negative solvatokinetic effects. A crystalline solid of DPF gives a strong yellow emission at about 532 nm; these phenomena are important for the application of DPF dye in organic photoemitting diode. The photochemical quantum yield of cis–trans isomerization of DPF was also determined in different solvents. The DPF dye displays solubilization in both cationic (CTAB) and anionic (SDS) micelle and may be used as a probe to determine the critical micelle concentration (CMC) of SDS and CTAB. - Highlights: • Organic pi conjugated molecule with a donor acceptor group was studied. • Crystalline solid of the molecule shows strong and intense yellow emission. • The dye displays solubilization in cationic micelle with abrupt change in emission intensity at CMC. • This work gives an insight into the application of organic luminescent material in various fields.

  6. Synthesis and characterization of Mn(III) chloro complexes with salen-type ligands

    International Nuclear Information System (INIS)

    Byun, Jong Chul; Han, Chung Hun; Lee, Nam Ho; Baik, Jong Seok; Park, Yu Chul

    2002-01-01

    A series of novel salen-type complexes ((Mn(III)(L acn )Cl): n=1∼11) containing Cl - ion were obtained by reactions of the Mn(CH 3 COO) 2 ·4H 2 O with the potentially tetradentate compartmental ligand (H 2 L acn ), prepared by condensation the of one mole of diamine (ethylenediamine, 1,3-propanediamine, o-phenylenediamine, and 2,2-dimethyl-1,3-propanediamine) with two moles of aldehyde (salicylaldehyde, 5-chloro- salicylaldehyde, 3,5-dichlorosalicylal-dehyde, and 3,5-di-tert-butyl-2-hydroxy-benzaldehyde) in a methanol solution . The resulting salen-type ligands and their Mn(III) complexes were identified and characterized by elemental analysis, conductivity, thermogravimetry and UV-VIS, IR, and NMR spectroscopy

  7. Synthesis, spectral characterizations and antimicrobial activity of some Schiff bases of 4-chloro-2-aminophenol

    Directory of Open Access Journals (Sweden)

    A. Seher Birteksöz

    2011-12-01

    Full Text Available A series of 4-chloro-2-[(arylmethylideneamino]phenols (1–11 including methoxy group were synthesized using appropriate synthetic route. The structures of the Schiff bases were characterized by FT-IR, UV-Vis, ESI-MS, 1H and 13C-NMR spectroscopic techniques and analytical methods. A relation is observed between melting points and existence of intramolecular hydrogen bonding. IR spectra of the compounds including and not including hydrogen bonding were compared. The compounds 2 and 4 show the characteristic UV bands attributed to the NH-forms. According to the 1H-NMR spectral data the compound 2 has the strongest intramolecular hydrogen bonding and the compound 6 shows two isomeric structure. On the other hand, antibacterial and antifungal activities of the compounds were investigated. Most of the compounds show selective activity toward S. epidermidis and C. albicans.

  8. Rotational study on the van der Waals complex 1-chloro-1,1-difluoroethane-argon

    Science.gov (United States)

    Wang, Juan; Chen, Junhua; Feng, Gang; Xia, Zhining; Gou, Qian

    2018-03-01

    The rotational spectrum of the van der Waals complex formed between 1-chloro-1,1-difluoroethane and argon has been investigated by using a pulsed jet Fourier transform microwave spectrometer. Only one set of rotational transitions belonging to the lowest energy conformer has been observed and assigned, although theoretical calculations suggest six stable conformers that might be observed. The observed conformer, according to the experimental evidence from two isotopologues (35Cl and 37Cl), adopts a configuration in which the argon atom is located, close to the sbnd CF2Cl top, between the CCF and CCCl planes (the dihedral angle ∠ ArCCCl is 65.2°). The distance between argon atom and the center of mass of CH3CF2Cl is 3.949(2) Å. The dissociation energy, with pseudo diatomic approximation, is evaluated to be 2.4 kJ mol- 1.

  9. Rotational Spectrum and Internal Rotation Barrier of 1-Chloro-1,1-difluoroethane

    Science.gov (United States)

    Alonso, José L.; López, Juan C.; Blanco, Susana; Guarnieri, Antonio

    1997-03-01

    The rotational spectra of 1-chloro-1,1-difluoroethane (HCFC-142b) has been investigated in the frequency region 8-115 GHz with Stark, waveguide Fourier transform (FTMW), and millimeter-wave spectrometers. Assignments in large frequency regions with the corresponding frequency measurements have been made for the ground andv18= 1 (CH3torsion) vibrational states of the35Cl isotopomer and for the ground state of the37Cl species. Accurate rotational, quartic centrifugal distortion, and quadrupole coupling constants have been determined from global fits considering all these states. SmallA-Einternal rotation splittings have been observed for thev18= 1 vibrational state using FTMW spectroscopy. The barrier height for the internal rotation of the methyl group has been determined to be 3751 (4) cal mol-1, in disagreement with the previous microwave value of 4400 (100) cal mol-1reported by G. Graner and C. Thomas [J. Chem. Phys.49,4160-4167 (1968)].

  10. Vibrational analysis of 4-chloro-3-nitrobenzonitrile by quantum chemical calculations

    Science.gov (United States)

    Sert, Yusuf; Çırak, Çağrı; Ucun, Fatih

    2013-04-01

    In the present study, the experimental and theoretical harmonic and anharmonic vibrational frequencies of 4-chloro-3-nitrobenzonitrile were investigated. The experimental FT-IR (400-4000 cm-1) and μ-Raman spectra (100-4000 cm-1) of the molecule in the solid phase were recorded. Theoretical vibrational frequencies and geometric parameters (bond lengths and bond angles) were calculated using ab initio Hartree Fock (HF), density functional B3LYP and M06-2X methods with 6-311++G(d,p) basis set by Gaussian 09 W program, for the first time. The assignments of the vibrational frequencies were performed by potential energy distribution (PED) analysis by using VEDA 4 program. The theoretical optimized geometric parameters and vibrational frequencies were compared with the corresponding experimental data, and they were seen to be in a good agreement with each other. Also, the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies were found.

  11. The Study of the Polymorphic System of 2-chloro-4-nitrobenzoic Acid

    International Nuclear Information System (INIS)

    Barskky, I.; Bernstein, J.; Stephens, P.; Stone, K.

    2008-01-01

    The solid-state behaviour of 2-chloro-4-nitrobenzoic ( 2c4n) acid has been reinvestigated. Infrared spectra, differential scanning calorimetry (DSC), and thermomicroscopy investigations as well as X-ray powder patterns for two modifications of the substance are described. Modification II is the thermodynamically stable crystal form from absolute zero to its transition point which occurs at approximately 97 C according to the DSC analysis. Above that temperature, the material transforms to modification I which undergoes dramatic evolution of its lattice parameters with increasing temperature. Synchrotron powder diffraction measurements confirm the existence of two polymorphic forms. Both modifications have been structurally characterized by single-crystal X-ray diffraction. The acid molecules in both crystal structures are organized into R22(8) dimer units at the first graph set level in modification I and at the second level in modification II.

  12. Degradation of 4-Chloro phenol by gamma radiation of 137Cs and X-rays

    International Nuclear Information System (INIS)

    Gonzalez J, J. C.; Jimenez B, J.; Cejudo A, J.

    2010-01-01

    This paper presents results of radiolytic degradation of 4-chloro phenol in the presence of TiO 2 , Al 2 O 3 and SiO 2 , using different radiation sources than 60 Co, which is so common in this type of experiment. The radiation sources used were X-rays with energy of 100 keV and radiation from 137 Cs (662 keV). After irradiation with a dose of 50 c Gy X-ray and TiO 2 obtained a degradation of about 5%, no degradation was obtained with 137 Cs source and other oxides. This may be due to the fact that X-rays have a linear energy transfer greater value, and in the case of TiO 2 present a crystalline structure, whereas the other two oxides are amorphous. Both characteristics result in better formation of a reactive species that allows the degradation of the compound. (Author)

  13. Distribution and excretion of methyl and phenyl mercury salts

    Energy Technology Data Exchange (ETDEWEB)

    Gage, J C

    1964-01-01

    The distribution, metabolism, and excretion of phenyl mercury acetate (P.M.A.) and of methyl mercury dicyanidiamide (M.M.D.) has been studied in the rat during the repeated subcutaneous administration of small doses over a period of six weeks, and for several weeks after a single dose. The results indicate that P.M.A. is absorbed unchanged into the circulation from which it is mainly removed by the liver and kidneys where it is metabolized and excreted in the feces and urine mostly as inorganic mercury. During repeated dosage the rats reached a steady state by the end of the second week when excretion approximately balanced intake. No measurable amount of mercury was found in the central nervous system. After repeated dosage with M.M.D. there is no clear indication of a steady state being reached after six weeks. There is an accumulation of organic mercury in all tissues, particularly in the red cells, and a progressive increase in the brain concentration. M.M.D. is more slowly released from the tissues than P.M.A. and the breakdown to inorganic mercury is low. The control of human exposure to alkyl and aryl mercury salts is considered in the light of these experimental observations. The recommendation that the concentration of alkyl mercury salts in the atmosphere should not exceed 0-01 mg/m/sup 3/ seems justifiable, but there appears to be no reason to establish the figure for aryl mercury salts below the 0-1 mg/m/sup 3/ recommended for inorganic mercury vapor. 13 references, 4 tables.

  14. Fluorescence and physical properties of the organic salt 2-chloro-4-nitrobenzoate–3-ammonium-phenol

    Energy Technology Data Exchange (ETDEWEB)

    Mani, Rajaboopathi, E-mail: mrajaboopathi@gmail.com [Department of Physics, Periyar University, Salem 636 011, Tamilnadu (India); Rietveld, Ivo B.; Nicolaï, Béatrice [Laboratoire de Chimie Physique, Faculté de Pharmacie, Université Paris Descartes, 75006 Paris (France); Varadharajan, Krishnakumar, E-mail: vkrishna_kumar@yahoo.com [Department of Physics, Periyar University, Salem 636 011, Tamilnadu (India); Louhi-Kultanen, Marjatta [Department of Chemical Technology, Lappeenranta University of Technology, Lappeenranta 53851 (Finland); Narasimhan, Surumbarkuzhali [Department of Physics, Government Arts College (Autonomous), Salem 636 007, Tamilnadu (India)

    2015-09-08

    Highlights: • Organic salt of 2-chloro-4-nitrobenzoate–3-ammonium-phenol (CNBA{sup −} · AP{sup +}) was grown by solution growth technique. • Single crystal X-ray diffraction demonstrate that two molecules were linked via N{sup +}–H⋯O{sup −} interactions. • The narrow spatial overlap between HOMO and LUMO leads to low ΔE{sub ST} = 73 meV. • The fluorescence emission was observed at ≈338 nm with Stokes shift of 53 nm. • The melting point of CNBA{sup −} · AP{sup +} is 187 °C which is higher than the individual components. - Abstract: Organic salt 2-chloro-4-nitrobenzoate (CNBA{sup −}) 3-ammonium-phenol (AP{sup +}) exhibits fluorescence at 338 nm in solution and frontier molecular orbitals generated from TDDFT calculations indicate that the ground state and the excited state are physically separated on AP{sup +} and CNBA{sup −}. The crystal structure and physical–chemical properties of the CNBA{sup −} · AP{sup +} were investigated using X-ray single crystal and powder diffraction, SEM, FTIR, UV–Vis–NIR, and fluorescence spectrometry. X-ray diffraction demonstrates that the two molecules are linked via N{sup +}–H⋯O{sup −} ammonium–carboxylate interactions, as expected considering their interaction propensities. Proton transfer has been confirmed by FTIR analysis. The melting point of CNBA{sup −} · AP{sup +} was observed at 186 °C, which is higher than pure CNBA (140 °C) or AP (120 °C). The observation of a spatially separated HOMO and LUMO possessing a narrow ΔE{sub ST} = 73.3 meV and an emission in the blue region is promising as an alternative method for the production of OLED materials.

  15. Understanding the scale of the single ion free energy: A critical test of the tetra-phenyl arsonium and tetra-phenyl borate assumption

    Science.gov (United States)

    Duignan, Timothy T.; Baer, Marcel D.; Mundy, Christopher J.

    2018-06-01

    The tetra-phenyl arsonium and tetra-phenyl borate (TATB) assumption is a commonly used extra-thermodynamic assumption that allows single ion free energies to be split into cationic and anionic contributions. The assumption is that the values for the TATB salt can be divided equally. This is justified by arguing that these large hydrophobic ions will cause a symmetric response in water. Experimental and classical simulation work has raised potential flaws with this assumption, indicating that hydrogen bonding with the phenyl ring may favor the solvation of the TB- anion. Here, we perform ab initio molecular dynamics simulations of these ions in bulk water demonstrating that there are significant structural differences. We quantify our findings by reproducing the experimentally observed vibrational shift for the TB- anion and confirm that this is associated with hydrogen bonding with the phenyl rings. Finally, we demonstrate that this results in a substantial energetic preference of the water to solvate the anion. Our results suggest that the validity of the TATB assumption, which is still widely used today, should be reconsidered experimentally in order to properly reference single ion solvation free energy, enthalpy, and entropy.

  16. Extending the fundamental imaging-depth limit of multi-photon microscopy by imaging with photo-activatable fluorophores.

    Science.gov (United States)

    Chen, Zhixing; Wei, Lu; Zhu, Xinxin; Min, Wei

    2012-08-13

    It is highly desirable to be able to optically probe biological activities deep inside live organisms. By employing a spatially confined excitation via a nonlinear transition, multiphoton fluorescence microscopy has become indispensable for imaging scattering samples. However, as the incident laser power drops exponentially with imaging depth due to scattering loss, the out-of-focus fluorescence eventually overwhelms the in-focal signal. The resulting loss of imaging contrast defines a fundamental imaging-depth limit, which cannot be overcome by increasing excitation intensity. Herein we propose to significantly extend this depth limit by multiphoton activation and imaging (MPAI) of photo-activatable fluorophores. The imaging contrast is drastically improved due to the created disparity of bright-dark quantum states in space. We demonstrate this new principle by both analytical theory and experiments on tissue phantoms labeled with synthetic caged fluorescein dye or genetically encodable photoactivatable GFP.

  17. Real-time detection of TDP1 activity using a fluorophore-quencher coupled DNA-biosensor

    DEFF Research Database (Denmark)

    Jensen, Pia Wrensted; Falconi, Mattia; Kristoffersen, Emil Laust

    2013-01-01

    structure of the biosensor. The specific action of TDP1 removes the quencher, thereby enabling optical detection of the fluorophore. Since the enzymatic action of TDP1 is the only “signal amplification” the increase in fluorescence may easily be followed in real-time and allows quantitative analyses of TDP1......Real-time detection of enzyme activities may present the easiest and most reliable way of obtaining quantitative analyses in biological samples. We present a new DNA-biosensor capable of detecting the activity of the potential anticancer drug target tyrosyl-DNA phosphodiesterase 1 (TDP1) in a very...... simple, high throughput, and real-time format. The biosensor is specific for Tdp1 even in complex biological samples, such as human cell extracts, and may consequently find future use in fundamental studies as well as a cancer predictive tool allowing fast analyses of diagnostic cell samples...

  18. Fast screening of glycosaminoglycan disaccharides by fluorophore-assisted carbohydrate electrophoresis (FACE): applications to biologic samples and pharmaceutical formulations.

    Science.gov (United States)

    Karousou, Evgenia; Asimakopoulou, Athanasia P; Zafeiropoulou, Vassiliki; Viola, Manuela; Monti, Luca; Rossi, Antonio; Passi, Alberto; Karamanos, Nikos

    2015-01-01

    Hyaluronan (HA), chondroitin sulfate (CS), and heparan sulfate (HS) are glycosaminoglycans (GAGs) with a great importance in biological processes as they participate in functional cell properties, such as migration, adhesion, and proliferation. A perturbation of the quantity and/or the sulfation of GAGs is often associated with pathological conditions. In this chapter, we present valuable and validated protocols for the analysis of HA-, CS-, and HS-derived disaccharides after derivatization with 2-aminoacridone and by using the fluorophore-assisted carbohydrate electrophoresis (FACE). FACE is a well-known technique and a reliable tool for a fast screening of GAGs, as it is possible to analyze 16 samples at the same time with one electrophoretic apparatus. The protocols for the gel preparation are based on the variations of the acrylamide/bisacrylamide and buffer concentrations. Different approaches for the extraction and purification of the disaccharides of various biologic samples and pharmaceutical preparations are also stressed.

  19. Autofluorescence Imaging With Near-Infrared Excitation:Normalization by Reflectance to Reduce Signal From Choroidal Fluorophores

    Science.gov (United States)

    Cideciyan, Artur V.; Swider, Malgorzata; Jacobson, Samuel G.

    2015-01-01

    Purpose. We previously developed reduced-illuminance autofluorescence imaging (RAFI) methods involving near-infrared (NIR) excitation to image melanin-based fluorophores and short-wavelength (SW) excitation to image lipofuscin-based flurophores. Here, we propose to normalize NIR-RAFI in order to increase the relative contribution of retinal pigment epithelium (RPE) fluorophores. Methods. Retinal imaging was performed with a standard protocol holding system parameters invariant in healthy subjects and in patients. Normalized NIR-RAFI was derived by dividing NIR-RAFI signal by NIR reflectance point-by-point after image registration. Results. Regions of RPE atrophy in Stargardt disease, AMD, retinitis pigmentosa, choroideremia, and Leber congenital amaurosis as defined by low signal on SW-RAFI could correspond to a wide range of signal on NIR-RAFI depending on the contribution from the choroidal component. Retinal pigment epithelium atrophy tended to always correspond to high signal on NIR reflectance. Normalizing NIR-RAFI reduced the choroidal component of the signal in regions of atrophy. Quantitative evaluation of RPE atrophy area showed no significant differences between SW-RAFI and normalized NIR-RAFI. Conclusions. Imaging of RPE atrophy using lipofuscin-based AF imaging has become the gold standard. However, this technique involves bright SW lights that are uncomfortable and may accelerate the rate of disease progression in vulnerable retinas. The NIR-RAFI method developed here is a melanin-based alternative that is not absorbed by opsins and bisretinoid moieties, and is comfortable to view. Further development of this method may result in a nonmydriatic and comfortable imaging method to quantify RPE atrophy extent and its expansion rate. PMID:26024124

  20. An evaluation of the performance and mechanistic action of the costabiliser N-phenyl-3-acetyl pyrrolidine-2,4-dione and its derivatives in poly(vinyl chloride)

    International Nuclear Information System (INIS)

    Chaudhry, H.I.

    1999-10-01

    N-phenyl-3-acetyl pyrrolidine-2,4-dione (F6) and its derivatives (F6c and F6d) have been investigated as costabilisers for PVC at processing temperatures, along with the commercial costabilisers: dehydroacetic acid (DHA) and Rhodiostab-83 (R83). Spectroscopic (fluorescence, Fourier-transform infrared and nuclear magnetic resonance) studies on PVC itself, and model compounds of PVC impurities (e.g. 4-chloro-2-hexene) have shown two distinct modes of action: in which a metal complex between the costabiliser and a metal soap stabiliser (zinc stearate and calcium stearate is the active entity, one in which costabiliser action is facilitated by release of zinc chloride. F6 was shown to substitute for allylic chloride by a C-alkylation reaction so inhibiting polyene formation and giving very good initial colour. It was demonstrated that F6 formed a complex with the zinc stearate at room temperature to give a chelate in which the zinc ion is tetracoordinated. Because the costabiliser is able to co-ordinate readily to zinc stearate, this leads to good initial colour, but a more rapid evolution of HCl ('short-term' costabilisation). When the -C=O substituent in the 3-position was replaced by a '-C=N-alkyl' (F6d), or a '-C=N-phenyl' (F6c) group, the behaviour was changed markedly. FTIR and HCl evolution showed that F6d was unstable at 180 deg. C and reacted with HCl evolved from the degraded PVC, decomposing into a basic gas and a structure similar to F6. F6d being more basic formed a complex with the Lewis acid ZnCI 2 instead of zinc stearate. F6c did not interact with the ZnCl 2 or ZnSt 2 , despite the fact that it has an extra nitrogen atom. The reason for this is that the π orbital system of the N-substituted phenyl ring in the 3-position in the pyrrolidine ring is conjugated with the C=N double bond. DHA also interacted with the zinc stearate, but this interaction was significant only at higher temperatures, i.e. after heating to processing temperatures. The

  1. A pilot-scale study of the precursors leading to the formation of mixed bromo-chloro dioxins and furans

    Energy Technology Data Exchange (ETDEWEB)

    Lemieux, P.M.; Stewart, E.S. [US EPA, Research Triangle Park, NC (USA). Office of Research & Development

    2004-02-01

    Experiments were performed in a pilot-scale rotary kiln incinerator simulator, where a mixture of chlorinated and brominated surrogate waste was burned in the presence of injected flyash from a coal-fired utility boiler. Measurements were made of semivolatile products of incomplete combustion (PICs), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDDs/Fs), and mixed bromo-chloro dibenzo-p-dioxins and furans (PXDDs/Fs). A statistical analysis of the data has been performed so that variability in the PCDDs/Fs can be accounted for by variation in the semivolatile PICs, particularly the chlorobenzenes (CBz) and chlorophenols (CPh). In addition, a statistical analysis was performed to investigate the variability of the PXDDs/Fs as a function of the concentrations of the semivolatile chlorinated, brominated, and mixed bromo-chloro organics.

  2. In vitro anti-leukemic activity and chemical transformation of the 5'-chloro-5'-deoxy derivative of cyclo-cytidine

    International Nuclear Information System (INIS)

    Stankovicova, M.; Bachrata, M.; Sveda, P.; Rauko, P.; Blesova, P.

    1995-01-01

    Hydrochloride of 5'-chloro-5'-deoxy-cytocytidine (Cl-cC) is an analogue of hydrochloride (cC), a pro-drug of the compound with of the compound with the strong anti-leukemic activity arabinosylcytosine (araC). This paper is devoted to the study of its cytotoxic activity in vitro and to the effect of acid alkaline conditions and temperature on its stability. Cl-cC inhibits not only the growth of L1210 leukemia cells in vitro and the DNA synthesis (IC 50 = 0.09 μmol/dm 3 ) but, at the same time, it has a weak effect on RNA synthesis (IC 50 > 250 μmol/dm 3 ) and no effect on proteosynthesis. In alkaline conditions Cl-cC is transformed to 5'-chloro-araC and 2',5'-anhydro-araC but is more stable in acid solutions. (author)

  3. Pulse-radiolytic one-electron reduction of anthraquinone and chloro-anthraquinones in aqueous-isopropanol-acetone mixed solvent

    International Nuclear Information System (INIS)

    Rath, M.C.; Pal, H.; Mukherjee, T.

    1996-01-01

    One-electron reduction of 9,10-anthraquinone and some chloro-anthraquinones and the characteristics of the semiquinones thus formed have been investigated in aqueous-isipropanol-acetone mixed solvent using electron pulse radiolysis technique. Spectroscopic characteristics, kinetic parameters of formation and decay, and the acid/base behaviour of the semiquinones have been investigated. The one-electron reduction potential of the quinones have been measured following electron transfer equilibria with a reference redox system (methyl viologen) and the values thus obtained have been compared with those of some other anthrasemiquinone systems. An analysis of the characteristics of the semiquinones shows that α-chloro substituents adjacent to the C=O group act as electron withdrawing groups. (author)

  4. Esterification of phenyl acetic acid with p-cresol using metal cation exchanged montmorillonite nanoclay catalysts.

    Science.gov (United States)

    Bhaskar, M; Surekha, M; Suma, N

    2018-02-01

    The liquid phase esterification of phenyl acetic acid with p -cresol over different metal cation exchanged montmorillonite nanoclays yields p -cresyl phenyl acetate. Different metal cation exchanged montmorillonite nanoclays (M n +  = Al 3+ , Zn 2+ , Mn 2+ , Fe 3+ , Cu 2+ ) were prepared and the catalytic activity was studied. The esterification reaction was conducted by varying molar ratio of the reactants, reaction time and catalyst amount on the yield of the ester. Among the different metal cation exchanged catalysts used, Al 3+ -montmorillonite nanoclay was found to be more active. The characterization of the material used was studied under different techniques, namely X-ray diffraction, scanning electron microscopy and thermogravimetric analysis. The product obtained, p -cresyl phenyl acetate, was identified by thin-layer chromotography and confirmed by Fourier transform infrared, 1 H NMR and 13 C NMR. The regeneration activity of used catalyst was also investigated up to fourth generation.

  5. Absorption and emission spectroscopic characterization of 10-phenyl-isoalloxazine derivatives

    International Nuclear Information System (INIS)

    Shirdel, J.; Penzkofer, A.; Prochazka, R.; Daub, J.; Hochmuth, E.; Deutzmann, R.

    2006-01-01

    The flavoquinone dyes 10-phenyl-isoalloxazine-3-acetic acid ethyl ester (1) and 10-(4-bromo-phenyl)-3-methyl-isoalloxazine (2) in dichloromethane, acetonitrile, and methanol are characterized by absorption and emission spectroscopy. Absorption cross-section spectra, stimulated emission cross-section spectra, fluorescence quantum distributions, quantum yields, lifetimes, and degrees of fluorescence polarization are determined. The blue-light photo-degradation of the dyes is studied. Mass spectroscopic measurements reveal the formation of phenyl-benzo-pteridine (isoalloxazine) derivatives, tetraaza-benzo-aceanthrylene derivatives, dihydro-quinooxaline derivatives, and pyrazino-carbazole derivatives. An enhancement of photo-degradation is observed by the formed photo-fragments

  6. Synthesis and structure-activity relationship exploration of some potent anti-cancer phenyl amidrazone derivatives.

    Science.gov (United States)

    Habashneh, Almeqdad Y; El-Abadelah, Mustafa M; Bardaweel, Sanaa K; Taha, Mutasem O

    2017-12-04

    Amidrazones have been reported to have significant anti-tumor properties against several cancer cell lines. The current project aims to profile the structure-anticancer activity relationship of phenyl-amidrazons. Fifteen phenyl-amidrazone-piperazine derivatives were prepared and tested against four cancer cell lines (leukemia, prostate, breast and colon cancers). Six compounds illustrated low micromolar anticancer IC50 values, while the remaining compounds were either inactive or of moderate potencies. All compounds were virtually nontoxic against normal fibroblast cells. Docking into the oncogenic kinase bcr/abl illustrated the critical importance of (i) p-halogen substituent on the ligand's phenyl ring and (ii) the presence of positive ionizable moiety at the ligand's piperazine fragment for anticancer activity. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  7. Radiation decomposition of alcohols and chloro phenols in micellar systems; Descomposicion por irradiacion de alcoholes y clorofenoles en sistemas micelares

    Energy Technology Data Exchange (ETDEWEB)

    Moreno A, J

    1999-12-31

    The effect of surfactants on the radiation decomposition yield of alcohols and chloro phenols has been studied with gamma doses of 2, 3, and 5 KGy. These compounds were used as typical pollutants in waste water, and the effect of the water solubility, chemical structure, and the nature of the surfactant, anionic or cationic, was studied. The results show that anionic surfactant like sodium dodecylsulfate (SDS), improve the radiation decomposition yield of ortho-chloro phenol, while cationic surfactant like cetyl trimethylammonium chloride (CTAC), improve the radiation decomposition yield of butyl alcohol. A similar behavior is expected for those alcohols with water solubility close to the studied ones. Surfactant concentrations below critical micellar concentration (CMC), inhibited radiation decomposition for both types of alcohols. However radiation decomposition yield increased when surfactant concentrations were bigger than the CMC. Aromatic alcohols decomposition was more marked than for linear alcohols decomposition. On a mixture of alcohols and chloro phenols in aqueous solution the radiation decomposition yield decreased with increasing surfactant concentration. Nevertheless, there were competitive reactions between the alcohols, surfactants dimers, hydroxyl radical and other reactive species formed on water radiolysis, producing a catalytic positive effect in the decomposition of alcohols. Chemical structure and the number of carbons were not important factors in the radiation decomposition. When an alcohol like ortho-chloro phenol contained an additional chlorine atom, the decomposition of this compound was almost constant. In conclusion the micellar effect depend on both, the nature of the surfactant (anionic or cationic) and the chemical structure of the alcohols. The results of this study are useful for wastewater treatment plants based on the oxidant effect of the hydroxyl radical, like in advanced oxidation processes, or in combined treatment such as

  8. Efficient sonochemical synthesis of alkyl 4-aryl-6-chloro-5-formyl-2-methyl-1,4-dihydropyridine-3-carboxylate derivatives.

    Science.gov (United States)

    Ruiz, Enrique; Rodríguez, Hortensia; Coro, Julieta; Niebla, Vladimir; Rodríguez, Alfredo; Martínez-Alvarez, Roberto; de Armas, Hector Novoa; Suárez, Margarita; Martín, Nazario

    2012-03-01

    A facile, efficient and environment-friendly protocol for the synthesis of 6-chloro-5-formyl-1,4-dihydropyridine derivatives has been developed by the convenient ultrasound-mediated reaction of 2(1H)pyridone derivatives with the Vilsmeier-Haack reagent. This method provides several advantages over current reaction methodologies including a simpler work-up procedure, shorter reaction times and higher yields. Copyright © 2011. Published by Elsevier B.V.

  9. Acute Oral Toxicity of 3-Chloro-4,4-dimethyl-2-oxazolidinone (Compound 1) in ICR Mice

    Science.gov (United States)

    1990-10-01

    number) FIELD GROUP SUB-GROUP Acute Oral Toxicity, N- Chloramine , Mouse, Mammalian Toxicology, Water Disinfectant , 3-Chloro-4, 4 -dimethyl-2...Amer Ind Hyg Assoc Q 1943; 10:93-96. 7. Mora EC, Kohl HH, Wheatley WB, et al. Properties or a new chloramine disinfectant and detoxicant. Poultry Sci...ORGANIZATION Mammalian Toxicology (If applicable) US Army Biomedical Research Division of Toxicology SGRD-ULE- T and Development Laboratory 6c. ADDRESS

  10. N-Chloro and N-bromosaccharins: valuable reagents for halogenation of electron rich aromatics and cohalogenation of alkenes

    Directory of Open Access Journals (Sweden)

    Souza Soraia P. L. de

    2003-01-01

    Full Text Available N-Chloro- and N-bromosaccharins react with electron rich aromatic compounds (anisole, acetanilide, N,N-dimethylaniline producing halogenated compounds. The reaction with N-bromosaccharin gives para- substituted compounds only, whereas N-chlorosaccharin produces orto and para mixtures (para isomer predominantly, ca. 4-5 : 1. The reactions of the N-halosaccharins with alkenes (cyclohexene, styrene, a-methylstyrene, and 1-hexene give the corresponding halohydrins.

  11. Radiation decomposition of alcohols and chloro phenols in micellar systems; Descomposicion por irradiacion de alcoholes y clorofenoles en sistemas micelares

    Energy Technology Data Exchange (ETDEWEB)

    Moreno A, J

    1998-12-31

    The effect of surfactants on the radiation decomposition yield of alcohols and chloro phenols has been studied with gamma doses of 2, 3, and 5 KGy. These compounds were used as typical pollutants in waste water, and the effect of the water solubility, chemical structure, and the nature of the surfactant, anionic or cationic, was studied. The results show that anionic surfactant like sodium dodecylsulfate (SDS), improve the radiation decomposition yield of ortho-chloro phenol, while cationic surfactant like cetyl trimethylammonium chloride (CTAC), improve the radiation decomposition yield of butyl alcohol. A similar behavior is expected for those alcohols with water solubility close to the studied ones. Surfactant concentrations below critical micellar concentration (CMC), inhibited radiation decomposition for both types of alcohols. However radiation decomposition yield increased when surfactant concentrations were bigger than the CMC. Aromatic alcohols decomposition was more marked than for linear alcohols decomposition. On a mixture of alcohols and chloro phenols in aqueous solution the radiation decomposition yield decreased with increasing surfactant concentration. Nevertheless, there were competitive reactions between the alcohols, surfactants dimers, hydroxyl radical and other reactive species formed on water radiolysis, producing a catalytic positive effect in the decomposition of alcohols. Chemical structure and the number of carbons were not important factors in the radiation decomposition. When an alcohol like ortho-chloro phenol contained an additional chlorine atom, the decomposition of this compound was almost constant. In conclusion the micellar effect depend on both, the nature of the surfactant (anionic or cationic) and the chemical structure of the alcohols. The results of this study are useful for wastewater treatment plants based on the oxidant effect of the hydroxyl radical, like in advanced oxidation processes, or in combined treatment such as

  12. Novel 2-phenyl-3-{4’-[N-(4”-aminophenylcarbamoyl]-phenyl}-quinazoline-4(3Hone-6-sulphonic acidbased mono azo reactive dyes

    Directory of Open Access Journals (Sweden)

    DIVYESH R. PATEL

    2011-02-01

    Full Text Available A series of new heterocyclic mono azo reactive dyes 7a–m were prepared by diazotization of 2-phenyl-3-{4’-[N-(4”-aminophenylcarbamoyl]-phenyl}-quinazoline-4(3H-one-6-sulphonic acid (3 and coupling with various cyanurated coupling components 6a–m and their dyeing performance on silk, wool and cotton fibres was assessed. These dyes were found to give a variety of colour shades with very good depth and levelness on the fibres. All the compounds were identified by conventional method (IR and 1H-NMR and elemental analyses. The percentage dye bath exhaustion on different fibres was reasonably good and acceptable. The dyed fibre showed moderate to very good fastness to light, washing and rubbing.

  13. 5-(2,4-Dichlorophenoxy-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde

    Directory of Open Access Journals (Sweden)

    S. Madan Kumar

    2016-07-01

    Full Text Available In the crystal structure of the title compound, C17H12Cl2N2O2, the pyrazole ring makes dihedral angles of 65.0 (2 and 43.9 (2° with the dichlorophenyl and phenyl rings, respectively. The dihedral angle between the chlorophenyl and phenyl rings is 59.1 (2°. In the crystal, the molecules are linked by C—H...O hydrogen bonds and weak C—Cl...π and C—H...π interactions, generating a three-dimensional network.

  14. Controlled switching of single-molecule junctions by mechanical motion of a phenyl ring

    Directory of Open Access Journals (Sweden)

    Yuya Kitaguchi

    2015-10-01

    Full Text Available Mechanical methods for single-molecule control have potential for wide application in nanodevices and machines. Here we demonstrate the operation of a single-molecule switch made functional by the motion of a phenyl ring, analogous to the lever in a conventional toggle switch. The switch can be actuated by dual triggers, either by a voltage pulse or by displacement of the electrode, and electronic manipulation of the ring by chemical substitution enables rational control of the on-state conductance. Owing to its simple mechanics, structural robustness, and chemical accessibility, we propose that phenyl rings are promising components in mechanical molecular devices.

  15. 1-[3-(2-Nitrophenyl-5-phenyl-2-pyrazolin-1-yl]ethanone

    Directory of Open Access Journals (Sweden)

    Huan-Mei Guo

    2010-07-01

    Full Text Available The title compound, C17H15N3O3, was prepared from 1-(2-nitrophenyl-3-phenylprop-2-en-1-one and hydrazine. The dihedral angle between the benzene and phenyl rings is 74.55 (2°. The pyrazoline ring is in a slight envelope conformation with the C atom bonded to the phenyl ring forming the flap. In the crystal structure, weak intermolecular C—H...O hydrogen bonds connect molecules into chains along [100].

  16. Oxidation of phenyl alanine by pyridinium chlorochromate in acidic DMF–water medium: A kinetic study

    Directory of Open Access Journals (Sweden)

    B.L. Hiran

    2016-11-01

    Full Text Available The kinetics of oxidation of phenyl alanine by pyridinium chlorochromate in DMF–water (70:30% mixture in presence of perchloric acid leads to the formation of corresponding aldehyde. The reaction is of first order each in [PCC], [HClO4] and [AA]. Michaelis–Menten type kinetics was observed with phenyl alanine. The reaction rates were determined at different temperatures [25, 30, 35, 40, 45, 50 °C] and the activation parameters were calculated. The reaction does not induce polymerization of acrylonitrile. With an increase in the amount of DMF in its aqueous mixture, the rate increases. A suitable mechanism for the reaction was postulated.

  17. Near Infrared Spectroscopic Identification of Alkyl Aromatic Esters and Phenyl Ketones

    Science.gov (United States)

    Nelyubov, D. V.; Vazhenin, D. A.; Kudriavtsev, A. A.; Buzolina, A. Yu.

    2018-03-01

    Bands characterizing the content of carbon atoms in alkyl (7177-7205 cm-1) and phenyl structural fragments (9175-9192 cm-1) in organic molecules were revealed by studying the near infrared spectra of such compounds. The optical density at the maxima of these absorption bands was shown to depend strongly on the fraction of carbon atoms in the corresponding fragments. The developed models proved to be adequate for determining the fraction of carbon atoms in alkyl aromatic esters and phenyl ketones. The feasibility of modeling the molecular structure of alkyl aromatic esters using regression models was demonstrated for the product of the condensation of oleic acid and benzyl alcohol.

  18. Synthesis and Characterization of Ti-Phenyl at SiO2 Core-Shell Nanoparticles Catalyst

    International Nuclear Information System (INIS)

    Syamsi Aini; Jon Efendi; Syamsi Aini; Jon Efendi

    2012-01-01

    This study highlights the potential use of Ti-Phenyl at SiO 2 core-shell nanoparticles as heterogeneous catalysis in oxidation reaction. The Ti-Phenyl at SiO 2 was synthesized by reduction of TiCl 4 and diazonium salt with sodium borohydride to produce phenyl titanium nanoparticles (Ti-Phenyl), followed by the silica shell coating using tetraethyl orthosilicate (TEOS). The Ti-Phenyl at SiO 2 nanoparticles were characterized by Fourier transform infrared (FTIR) spectrometer, diffuse reflectance (DR) UV-visible spectrometer, thermogravimetric analyzer (TGA), X-ray diffraction (XRD) spectrometer, field emission scanning electron microscope (FESEM) and transmission electron microscope (TEM). The core-shell size of Ti-Phenyl at SiO 2 was in the range of 40 to 100 nm with its core composed with an agglomeration of Ti-Phenyl. The Ti-Phenyl at SiO 2 was active as a catalyst in the liquid phase epoxidation of 1-octene with aqueous hydrogen peroxide as an oxidant. (author)

  19. UV-visible spectrum of the phenyl radical and kinetics of its reaction with NO in the gas phase

    DEFF Research Database (Denmark)

    Wallington, T.J.; Egsgaard, H.; Nielsen, O.J.

    1998-01-01

    Pulse radiolysis transient UV-visible absorption spectroscopy was used to study the UV-visible absorption spectrum (225-575 nm) of the phenyl radical, C6H5(.), and kinetics of its reaction with NO. Phenyl radicals have a strong broad featureless absorption in the region of 225-340 nm...

  20. Effect of the modification of a natural mexican zeolite in the sorption of cadmium and 4-chloro phenol

    International Nuclear Information System (INIS)

    Cortes M, R.

    2007-01-01

    Clinoptilolite type zeolite is a material of relative abundance in Mexico, which possess ion exchange properties and it can be used in the removal of metal ions from polluted waters. The external surface of zeolites can be modified with cationic surfactants. This modification could have a negative effect on the removal of metal ions and provides to the material the capacity to adsorb phenolic compounds. For this reason, it is important to know the capability of the modified material on the sorption of metal ions and phenolic compounds, simultaneously. The aim of this work was to evaluate the effect of the external surface modification with surfactant of a Mexican zeolite over its sorption capacity of cadmium and 4-chloro phenol, in batch and column systems. To accomplish that, a clinoptilolite type zeolitic rock from a deposit located in the state of Sonora, Mexico, was used. It was ground, sieved and characterized with different techniques; and its external surface area was modified with hexadecyltrimethylammonium bromide (HDTMA-Br). A grain size fraction was selected to carry out sorption kinetics and equilibrium experiments, as well as packed column tests with zeolitic material and solutions of cadmium and 4-chloro phenol. There are different models proposed in literature that are used to describe sorption kinetics and equilibrium. In this work, the sorption experimental results were adjusted to some of these models to identify controlling mechanisms on the kinetics and equilibrium of the studied systems. The results showed that the cadmium adsorption on natural and modified zeolite was similar in batch systems. For the case of 4-chloro phenol sorption, it was observed that natural zeolite does not retain this compound, while in modified zeolite the sorption is better than other comparable materials. The results also showed that for the case of cadmium sorption, the mechanism involved was ion exchange; while for sorption of 4-chloro phenol, a partition mechanism

  1. [Determination of residual solvents in 7-amino-3-chloro cephalosporanic acid by gas chromatography].

    Science.gov (United States)

    Ma, Li; Yao, Tong-wei

    2011-01-01

    To develop a gas chromatography method for determination of residual solvents in 7-amino-3-chloro cephalosporanic acid (7-ACCA). The residual levels of acetone, methanol, dichloromethane, ethyl acetate, isobutanol, pyridine and toluene in 7-ACCA were measured by gas chromatography using Agilent INNOWAX capillary column (30 m × 0.32 mm,0.5 μm). The initial column temperature was 70° maintained for 6 min and then raised (10°C/min) to 160°C for 1 min. Nitrogen gas was used as carrier and FID as detector. The flow of carrier was 1.0 ml/min, the temperature of injection port and detector was 200°C and 250°C, respectively. The limits of detection for acetone, methanol, dichloromethane, ethyl acetate, isobutanol, pyridine, toluene in 7-ACCA were 2.5 μg/ml, 1.5 μg/ml, 15 μg/ml, 2.5 μg/ml, 2.5 μg/ml, 2.5 μg/ml and 11 μg/ml, respectively. Only acetone was detected in the sample, and was less than the limits of Ch.P. The method can effectively detect the residual solvents in 7-ACCA.

  2. Synthesis, thermogravimetric, spectroscopic and theoretical characterization of copper(II) complex with 4-chloro-2-nitrobenzenosulfonamide

    Science.gov (United States)

    Camí, G.; Chacón Villalba, E.; Di Santi, Y.; Colinas, P.; Estiu, G.; Soria, D. B.

    2011-05-01

    4-Chloro-2-nitrobenzenesulfonamide (ClNbsa) was purified and characterized. A new copper(II) complex, [Cu(ClNbsa) 2(NH 3) 2], has been prepared using the sulfonamide as ligand. The thermal behavior of both, the ligand and the Cu(II) complex, was investigated by thermogravimetric analyses (TG) and differential thermal analysis (DT), and the electronic characteristics analyzed by UV-VIS, FTIR, Raman and 1H NMR spectroscopies. The experimental IR, Raman and UV-VIS spectra have been assigned on the basis of DFT calculations at the B3LYP level of theory using the standard (6-31 + G ∗∗) basis set. The geometries have been fully optimized in vacuum and in modeled dimethylsulfoxide (DMSO) solvent, using for the latter a continuum solvation model that reproduced the experimental conditions of the UV-VIS spectroscopy. The theoretical results converged to stable conformations for the free sulfonamide and for the complex, suggesting for the latter a distorted square planar geometry in both environments.

  3. Degradation of 4-Chloro phenol by gamma radiation of {sup 137}Cs and X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez J, J. C. [Instituto Tecnologico de Toluca, Av. Tecnologico s/n, Ex-Rancho La Virgen, 52140 Metepec, Estado de Mexico (Mexico); Jimenez B, J.; Cejudo A, J., E-mail: jaime.jimenez@inin.gob.m [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2010-07-01

    This paper presents results of radiolytic degradation of 4-chloro phenol in the presence of TiO{sub 2}, Al{sub 2}O{sub 3} and SiO{sub 2}, using different radiation sources than {sup 60}Co, which is so common in this type of experiment. The radiation sources used were X-rays with energy of 100 keV and radiation from {sup 137}Cs (662 keV). After irradiation with a dose of 50 c Gy X-ray and TiO{sub 2} obtained a degradation of about 5%, no degradation was obtained with {sup 137}Cs source and other oxides. This may be due to the fact that X-rays have a linear energy transfer greater value, and in the case of TiO{sub 2} present a crystalline structure, whereas the other two oxides are amorphous. Both characteristics result in better formation of a reactive species that allows the degradation of the compound. (Author)

  4. Effects of Acupuncture on 1-Chloro-2,4-dinitrochlorobenzene-Induced Atopic Dermatitis

    Directory of Open Access Journals (Sweden)

    Ji-Yeun Park

    2013-01-01

    Full Text Available Though the effects of acupuncture in atopic dermatitis have been proven in clinical studies, its mechanism remains unclear. In this study, we investigate the effectiveness and mechanism of action for acupuncture treatment on the LI11 meridian point for treatment of allergic contact dermatitis. BALB/c mice received 1-chloro-2,4-dinitrobenzene (DNCB application to induce skin inflammation. Acupuncture treatment on LI11 significantly inhibited cutaneous hyperplasia, serum IgE levels, and expression of proinflammatory cytokine (IL-4, IL-8, and TNF-α mRNA and NF-κB, ERK1/2, JNK, and p38 proteins. Acupuncture treatment of local points also inhibited cutaneous hyperplasia and serum IgE levels; however, it was not effective in regulating proinflammatory cytokines and proteins. In addition, LI11 treatment is more effective at reducing serum IgE levels and pro-inflammatory cytokines and proteins than local point treatment. These results suggest that acupuncture treatment is effective in alleviating allergic contact dermatitis by reducing pro-inflammatory cytokines and proteins.

  5. Structural, antimicrobial and computational characterization of 1-benzoyl-3-(5-chloro-2-hydroxyphenyl)thiourea.

    Science.gov (United States)

    Atiş, Murat; Karipcin, Fatma; Sarıboğa, Bahtiyar; Taş, Murat; Çelik, Hasan

    2012-12-01

    A new thiourea derivative, 1-benzoyl-3-(5-chloro-2-hydroxyphenyl)thiourea (bcht) has been synthesized from the reaction of 2-amino-4-chlorophenol with benzoyl isothiocyanate. The title compound has been characterized by elemental analyses, FT-IR, (13)C, (1)H NMR spectroscopy and the single crystal X-ray diffraction analysis. The structure of bcht derived from X-ray diffraction of a single crystal has been presented. The structural and spectroscopic data of the molecule in the ground state were calculated by using density functional method using 6-311++G(d,p) basis set. The complete assignments of all vibrational modes were performed on the basis of the total energy distributions (TED). Isotropic chemical shifts ((13)C NMR and (1)H NMR) were calculated using the gauge-invariant atomic orbital (GIAO) method. Theoretical calculations of bond parameters, harmonic vibration frequencies and nuclear magnetic resonance are in good agreement with experimental results. The UV absorption spectra of the compound that dissolved in ACN and MeOH were recorded. Bcht was also screened for antimicrobial activity against pathogenic bacteria and fungi. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Synthesis and Crystal Structure of 1-Chloro-2-methyl-4-nitrobenzene

    Directory of Open Access Journals (Sweden)

    Jim Simpson

    2012-03-01

    Full Text Available The title compound (3 was prepared from 4-chloroaniline in good yield on successive oxidation and methylation and its crystal and molecular structure is reported. The compound crystallizes in the monoclinic space group P 21/n with unit cell dimensions a = 13.5698(8, b = 3.7195 (3, c = 13.5967 (8 Å, ß = 91.703(3 °, V = 685.96 (10 Å3. The molecule is essentially planar with a dihedral angle of 6.2(3 ° between the nitro group and the phenyl ring. The crystal structure is stabilised by π...π contacts between adjacent benzene rings together with C–H...O hydrogen bonds and close Cl...O contacts.

  7. Synthesis of highly fluorescent silica nanoparticles in a reverse microemulsion through double-layered doping of organic fluorophores

    International Nuclear Information System (INIS)

    Yoo, Hyojong; Pak, Joonsung

    2013-01-01

    Water-soluble, highly fluorescent double-layered silica nanoparticles (FL-DLSN) have been successfully synthesized through a reverse (water-in-oil) microemulsion method. The microemulsion was prepared by mixing a surfactant (Brij35), co-surfactant, organic solvent, water, and fluorescein as an organic fluorophore. The sizes of the silica nanoparticles were successfully controlled in the reverse microemulsion using Brij35 by changing the water-to-Brij35 ratio and by adding HCl. Initially, tetraethylorthosilicate was hydrolyzed by adding NH 4 OH as a catalyst and then polymerized to generate core fluorescent silica nanoparticles with fluorescein. 3-(Aminopropyl)triethoxysilane (APTS) was sequentially added into the reaction mixture, and reacted on the surface of pre-generated core silica nanoparticles to form the second layer in the form of a shell. The second silica layer that was derived from the condensation of APTS effectively protected the fluorescein dye within the silica matrix. This is a novel and simple synthetic approach to generate highly fluorescent, monodispersed silica nanoparticles by doping organic molecules into a silica matrix.Graphical Abstract

  8. Synthesis of highly fluorescent silica nanoparticles in a reverse microemulsion through double-layered doping of organic fluorophores

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Hyojong, E-mail: hyojong@hallym.ac.kr; Pak, Joonsung [Hallym University, Department of Chemistry (Korea, Republic of)

    2013-05-15

    Water-soluble, highly fluorescent double-layered silica nanoparticles (FL-DLSN) have been successfully synthesized through a reverse (water-in-oil) microemulsion method. The microemulsion was prepared by mixing a surfactant (Brij35), co-surfactant, organic solvent, water, and fluorescein as an organic fluorophore. The sizes of the silica nanoparticles were successfully controlled in the reverse microemulsion using Brij35 by changing the water-to-Brij35 ratio and by adding HCl. Initially, tetraethylorthosilicate was hydrolyzed by adding NH{sub 4}OH as a catalyst and then polymerized to generate core fluorescent silica nanoparticles with fluorescein. 3-(Aminopropyl)triethoxysilane (APTS) was sequentially added into the reaction mixture, and reacted on the surface of pre-generated core silica nanoparticles to form the second layer in the form of a shell. The second silica layer that was derived from the condensation of APTS effectively protected the fluorescein dye within the silica matrix. This is a novel and simple synthetic approach to generate highly fluorescent, monodispersed silica nanoparticles by doping organic molecules into a silica matrix.Graphical Abstract.

  9. Identification of nodal tissue in the living heart using rapid scanning fiber-optics confocal microscopy and extracellular fluorophores.

    Science.gov (United States)

    Huang, Chao; Kaza, Aditya K; Hitchcock, Robert W; Sachse, Frank B

    2013-09-01

    Risks associated with pediatric reconstructive heart surgery include injury of the sinoatrial node (SAN) and atrioventricular node (AVN), requiring cardiac rhythm management using implantable pacemakers. These injuries are the result of difficulties in identifying nodal tissues intraoperatively. Here we describe an approach based on confocal microscopy and extracellular fluorophores to quantify tissue microstructure and identify nodal tissue. Using conventional 3-dimensional confocal microscopy we investigated the microstructural arrangement of SAN, AVN, and atrial working myocardium (AWM) in fixed rat heart. AWM exhibited a regular striated arrangement of the extracellular space. In contrast, SAN and AVN had an irregular, reticulated arrangement. AWM, SAN, and AVN tissues were beneath a thin surface layer of tissue that did not obstruct confocal microscopic imaging. Subsequently, we imaged tissues in living rat hearts with real-time fiber-optics confocal microscopy. Fiber-optics confocal microscopy images resembled images acquired with conventional confocal microscopy. We investigated spatial regularity of tissue microstructure from Fourier analysis and second-order image moments. Fourier analysis of fiber-optics confocal microscopy images showed that the spatial regularity of AWM was greater than that of nodal tissues (37.5 ± 5.0% versus 24.3 ± 3.9% for SAN and 23.8 ± 3.7% for AVN; Pfiber-optics confocal microscopy. Application of the approach in pediatric reconstructive heart surgery may reduce risks of injuring nodal tissues.

  10. Spectrofluorimetric determination of gemifloxacin mesylate and linezolid in pharmaceutical formulations: Application of quinone-based fluorophores and enhanced native fluorescence

    Directory of Open Access Journals (Sweden)

    Moussa Bahia Abbas

    2014-03-01

    Full Text Available Quinone-based fluorophores and enhanced native fluorescence techniques were applied for a fast quantitative analysis of gemifloxacin mesylate (GEM and linezolid (LIN in pharmaceutical formulations. For this purpose, three sensitive, accurate and precise spectrofluorimetric methods were developed. GEM, as an n-electron donor, reacts with 7,7,8,8-tetracyanoquinodimethane (method A and 2,5-dichloro-3,6-dihydroxy-p-benzoquinone (method B as п-electron acceptors, forming charge transfer complexes that exhibit high fluorescence intensity at 441 and 390 nm upon excitation at 260 and 339 nm, respectively. Method C depends on measurement of enhanced native fluorescence of LIN in phosphate buffer (pH 5 at 380 nm upon excitation at 260 nm. Experimental factors affecting fluorescence intensity were optimized. Linearity was obtained over concentration ranges 50-500, 10-60 and 20-400 ng mL-1 for methods A, B and C, respectively. The developed methods were validated and successfully applied for determination of the cited drugs in tablets.

  11. Thermodynamic models for determination of 3-chloro-N-phenylphthalimide solubility in binary solvent mixtures of (acetone, ethyl acetate or 1,4-dioxane + methanol)

    International Nuclear Information System (INIS)

    Xie, Yong; Shi, Hongwei; Du, Cunbin; Cong, Yang; Wang, Jian; Zhao, Hongkun

    2016-01-01

    Highlights: • Solubility of 3-chloro-N-phenylphthalimide in binary mixed solvents were determined. • Solubility data were correlated and calculated by five models. • The standard molar enthalpy for the dissolution processes were calculated. - Abstract: The solubility of 3-chloro-N-phenylphthalimide in binary mixed solvents of (acetone + methanol, ethyl acetate + methanol and 1,4-dioxane + methanol) were determined experimentally by using the isothermal dissolution equilibrium method within the temperature range from (288.15 to 323.15) K under atmosphere pressure. For the binary systems of (acetone + methanol) and (1,4-dioxane + methanol), the solubility of 3-chloro-N-phenylphthalimide increased with increasing temperature and mass fraction of acetone or 1,4-dioxane; and for the (ethyl acetate + methanol) system, at a given composition of ethyl acetate, the solubility of 3-chloro-N-phenylphthalimide increased with an increase in temperature; nevertheless at the same temperature, they increased at first and then decreased with increasing mass fraction of 1,4-dioxane. At the same temperature and mass fraction of acetone, ethyl acetate or 1,4-dioxane, the solubility of 3-chloro-N-phenylphthalimide was greater in (1,4-dioxane + methanol) than in the other two mixed solvents. The solubility values were correlated by employing the Jouyban–Acree model, van’t Hoff–Jouyban–Acree model, Apelblat–Jouyban–Acree model, Ma model, and Sun model. On the whole, the Ma model and Sun model were proven to provide good representation of the experimental solubility results. Furthermore, the dissolution enthalpies of the dissolution process were calculated. The dissolution process of 3-chloro-N-phenylphthalimide in these mixed solvents is endothermic. The experimental solubility and the models in this study could be helpful in purifying 3-chloro-N-phenylphthalimide.

  12. (2E-3-(3-Methoxy-1-phenyl-1H-pyrazol-4-yl-2-propenal

    Directory of Open Access Journals (Sweden)

    Algirdas Šačkus

    2009-12-01

    Full Text Available The palladium-catalyzed reaction of 4-bromo-3-methoxy-1-phenyl-1H-pyrazole with acrolein diethyl acetal gives the title compound in good yield. Detailed spectroscopic data (1H NMR, 13C NMR, 15N NMR, IR, MS are presented.

  13. 4-Benzyl-6-bromo-2-phenyl-4H-imidazo[4,5-b]pyridine

    Directory of Open Access Journals (Sweden)

    Y. Ouzidan

    2010-04-01

    Full Text Available The imidazopyridine fused ring in the title compound, C19H14BrN3, is almost coplanar with the phenyl ring at the 2-position of the five-membered ring [dihedral angle = 2.4 (1. The crystal structure features short Br...Br contacts [3.562 (1 Å].

  14. 1-phenyl-2-decanoylamino-3-morpholino-1-propanol chemosensitizes neuroblastoma cells for taxol and vincristine

    NARCIS (Netherlands)

    Sietsma, H; Veldman, Robert; Ausema, B; Nijhof, W; Kamps, W; Vellenga, E; Kok, JW

    In this study, we show that an inhibitor of glycosphingolipid biosynthesis, D,L-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), increases the chemosensitivity of neuroblastoma tumor cells for Taxol and vincristine. At noneffective low doses of Taxol or vincristine, the addition of a

  15. Crystal structure of (E-N-phenyl-N′-[1-(thiophen-2-ylethylidene]formohydrazide

    Directory of Open Access Journals (Sweden)

    C. S. Dileep

    2014-09-01

    Full Text Available In the title compound, C13H12N2OS, the planes of the thiophene and phenyl rings are nearly perpendicular to each other, making a dihedral angle of 86.42 (12°. In the crystal, molecules are linked by C—H...O hydrogen bonds, forming a helical chain along the b-axis direction.

  16. Influencing the electronic interaction in diferrocenyl-1-phenyl-1H-pyrroles.

    Science.gov (United States)

    Hildebrandt, Alexander; Lang, Heinrich

    2011-11-28

    Functionalised diferrocenyl-1-phenyl-1H-pyrroles were synthesised using Negishi C,C cross-coupling reactions. The influence of different substituents at the phenyl moiety on the electronic interaction was studied using electrochemistry (cyclic and square-wave voltammetry) and spectro-electrochemistry (in situ UV/Vis-NIR spectroscopy). The ferrocenyl moieties gave rise to two sequential, reversible redox processes in each of the diferrocenyl-1-phenyl-1H-pyrroles. The observed ΔE(1/2) values (ΔE(1/2) = difference between first and second oxidation) range between 420 and 480 mV. A linear relationship between the Hammett constants σ of the substituents and the separation of the redox potentials exists. The NIR measurements confirm electronic communication between the iron centers as intervalence charge transfer (IVCT) absorptions were observed in the corresponding mixed-valent monocationic species. All compounds were classified as class II systems according to Robin and Day (M. B. Robin and P. Day, Adv. Inorg. Chem., 1967, 10, 247-423). The oscillator strength of the charge transfer transition highly depends on the electron donating or electron withdrawing character of the phenyl substituents. This enables direct tuning of the intermetallic communication by simple modification of the molecule's functional group. Hence, this series of molecules may be regarded as model compounds for single molecule transistors.

  17. Microwave Accelerated Polymerization of 2-Phenyl-2-Oxazoline: Microwave or Temperature Effects?

    NARCIS (Netherlands)

    Hoogenboom, R.; Leenen, M.A.M.; Wiesbrock, F.D.; Schubert, U.S.

    2005-01-01

    Summary: Investigations regarding the cationic ring-opening polymerization of 2-phenyl-2-oxazoline under microwave irradiation and conventional heating are reported. This study was inspired by contradictory reports of the (non-)existence of non-thermal microwave effects that might accelerate the

  18. [2-(2,4-dimethylphenylthio)phenyl] aniline and its amide derivatives ...

    Indian Academy of Sciences (India)

    YOGESH PATIL

    2018-02-15

    Feb 15, 2018 ... These derivatives could be considered as a precursor structure for further design of antituberculosis agent. Keywords. [2-(2,4-dimethylphenylthio)phenyl] aniline; antituberculosis activity; cytotoxicity. 1. Introduction. Tuberculosis (TB) is a contagious disease caused by the. Mycobacterium tuberculosis (MTB).

  19. Isolation of novel para-pentyl phenyl benzoate from Mondia whitei ...

    African Journals Online (AJOL)

    Results: The structure of the compound was elucidated as para pentyl phenyl benzoate. The neuropharmacological evaluation of the compound indicated significant (p<0.05) depression of the central nervous system. The binding characteristics of the compound to gamma amino butyric acid A receptors appears to be more ...

  20. Asimetric synthesis of alpha-phenyl amino acids; Sintesis asimetrica de alfa-fenilaminoacidos

    Energy Technology Data Exchange (ETDEWEB)

    Caltiviela, C.; Diaz de Villegas, M.D.; Galvez, J.A.; Lapena, Y. [Departamento de Quimica Organica, Universidad de Zaragoza, Zaragoza (Spain)

    1994-12-31

    A new synthetic strategy to obtain alpha-phenyl amino acids in enantiomerically pure form is described. The new route is based on the highly diastereoselective alkylation of (1S,2R,4R)-10-dicyclohexylsulfamoylisobornyl 2-phenylcianoacetate and subsequent curtis type rearrangement of the alkylated compound with total retention of configuration. 17 refs

  1. Pharmacological Studies of p, N-(3, 4-Methylenedioxy phenyl Benzoic Acid (RRL-1364 - Part-I

    Directory of Open Access Journals (Sweden)

    Dahanukar Sharadini

    1978-01-01

    Full Text Available Detailed pharmacological investigations of p-N-(3, 4-methylene dioxy phenyl benzoic acid revealed marked hypotensive action which was dose dependent and most marked in cats; it was absent in rats. Atropine could block this hypotensive action, thus suggest-ing cholinomimetic mechanism. Further studies indicated that the hypotension produced was central and possibly medullary in origin.

  2. Substituent effects on the excited states of phenyl-capped phenylene vinylene tetramers

    NARCIS (Netherlands)

    Candeias, L.P.; Gelinck, G.H.; Piet, J.J.; Piris, J.; Wegewijs, B.; Peeters, E.; Wildeman, J.; Hadziioannou, G.; Müllen, K.

    2001-01-01

    The singlet and triplet excited states of phenyl-capped tetramers of phenylene vinylene with different alkyl, alkoxy or cyano substituents, were investigated in benzene solution. The lowest singlet states were studied by laser flash-photolysis with time-resolved microwave conductivity and

  3. Synthesis of a new scintillator 2-phenyl-5(4-p-terphenylyl)Oxazole

    International Nuclear Information System (INIS)

    Dhane, D.L.; Gaiki, G.M.

    1979-01-01

    Friedel-Crafts reaction between hippuryl chloride and p-terphenyl gave benzoylaminomethyl-(4-p-terphenylyl) ketone (II) which on cyclodehydration gave hitherto unreported 2-phenyl-5-(4-p-terphenylyl) oxazole (I). IR, UV absorption and fluorescence spectra of I have been recorded. The performance of I as a scintillator solute has been tested. (auth.)

  4. Page 1 Constitution of Dalbergin—V 109 (ii) 3-Bromo-4-phenyl-6: 7 ...

    Indian Academy of Sciences (India)

    of 4-phenyl-6: 7: 8-trimethoxy coumarin (3.1 g) in glacial acetic acid (20 c.c.) was added a ... i.e., the colour reaction with magnesium and hydrochloric acid and the trans- formation with alkali and mercuric oxide into coumarilic acids are shown.

  5. In vivo evaluation of [{sup 11}C]N-(2-chloro-5-thiomethylphenyl)-N'- (3-methoxy-phenyl)-N'-methylguanidine ([{sup 11}C]GMOM) as a potential PET radiotracer for the PCP/NMDA receptor

    Energy Technology Data Exchange (ETDEWEB)

    Waterhouse, Rikki N. E-mail: rnw7@columbia.edu; Slifstein, Mark; Dumont, Filip; Zhao Jun; Chang, Raymond C.; Sudo, Yasuhiko; Sultana, Abida; Balter, Andrew; Laruelle, Marc

    2004-10-01

    The development of imaging methods to measure changes in NMDA ion channel activation would provide a powerful means to probe the mechanisms of drugs and device based treatments (e.g., ECT) thought to alter glutamate neurotransmission. To provide a potential NMDA/PCP receptor PET tracer, we synthesized the radioligand [{sup 11}C]GMOM (K{sub i} = 5.2 {+-}0.3 nM; log P = 2.34) and evaluated this ligand in vivo in awake male rats and isoflurane anesthetized baboons. In rats, the regional brain uptake of [{sup 11}C]GMOM ranged from 0.75{+-}0.13% ID/g in the medulla and pons to 1.15{+-}0.17% ID/g in the occipital cortex. MK801 (1 mg/kg i.v.) significantly reduced (24-28%) [{sup 11}C]GMOM uptake in all regions. D-serine (10 mg/kg i.v.) increased [{sup 11}C]GMOM %ID/g values in all regions (10-24%) reaching significance in the frontal cortex and cerebellum only. The NR2B ligand RO 25-6981 (10 mg/kg i.v.) reduced [{sup 11}C]GMOM uptake significantly (24-38%) in all regions except for the cerebellum and striatum. Blood activity was 0.11{+-}0.03 %ID/g in the controls group and did not vary significantly across groups. PET imaging in isoflurane-anesthetized baboons with high specific activity [{sup 11}C]GMOM provided fairly uniform regional brain distribution volume (V{sub T}) values (12.8-17.1 ml g{sup -1}). MK801 (0.5 mg/kg, i.v., n = 1, and 1.0 mg/kg, i.v., n = 1) did not significantly alter regional V{sub T} values, indicating a lack of saturable binding. However, the potential confounding effects associated with ketamine induction of anesthesia along with isoflurane maintenance must be considered because both agents are known to reduce NMDA ion channel activation. Future and carefully designed studies, presumably utilizing an optimized NMDA/PCP site tracer, will be carried out to further explore these hypotheses. We conclude that, even though [{sup 11}C]GMOM is not an optimized PCP site radiotracer, its binding is altered in vivo in awake rats as expected by modulation of NMDA ion channel activity by MK801, D-serine or RO 25-6981. The development of higher affinity NMDA/PCP site radioligands is in progress.

  6. Synthesis, characterization, crystal structure, and thermal analysis of 2-chloro-N-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-yl) acetamide

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, R. [University of Jammu, X-ray Crystallography Laboratory, Post-Graduate Department of Physics & Electronics (India); Nayak, P. S.; Narayana, B. [Mangalore University, Mangalagangotri, Department of Studies in Chemistry (India); Kant, R., E-mail: rkvk.paper11@gmail.com [University of Jammu, X-ray Crystallography Laboratory, Post-Graduate Department of Physics & Electronics (India)

    2015-12-15

    The title compound, C{sub 13}H{sub 14}O{sub 2}N{sub 3}Cl, has been synthesized by the reaction of chloroacetyl chloride with 4-aminoantipyrine in basic media and characterized by FT-IR, CHN elemental analysis, UV-Vis, TGA, DTA, DSC and single crystal X-ray diffraction. crystals are monoclinic, sp. gr. P2{sub 1}/c, a = 6.9994(6), b = 12.4035(13), c = 15.836(2) Å, β = 100.367(9)°, Z = 4. The crystal structure is stabilized by N–H···O and C–H···O interactions, the former interactions result in the formation of dimers corresponding to R{sub 2}{sup 2} (10) graphset motif and the dimers are further connected by C–H···O hydrogen bonding forming chains. In addition, the thermal stability of the compound was determined by TGA, DTA, DSC analysis, and absorption at λ{sub max} = 298 nm was determined by UV-Vis spectrophotometer.

  7. 7-Chloro-11a-phenyl-2,3,5,10,11,11a-hexahydro-1H-pyrrolo[2,1-c][1,4]benzodiazepine-5,11-dione

    Directory of Open Access Journals (Sweden)

    Vahan Martirosyan

    2008-03-01

    Full Text Available The title compound, C18H15ClN2O2, is a potential human immunodeficiency virus type-1 (HIV-1 non-nucleoside reverse transcriptase inhibitor. The pyrrolidine ring adopts an envelope and the diazepine ring a boat conformation. In the crystal structure, two isomers (R and S form centrosymmetric dimers via N—H...O hydrogen bonds.

  8. Synthesis and Evaluation of Tricarbonyl 99mTc-Labeled 2-(4-Chloro)phenyl-imidazo[1,2-a]pyridine Analogs as Novel SPECT Imaging Radiotracer for TSPO-Rich Cancer

    Science.gov (United States)

    Choi, Ji Young; Iacobazzi, Rosa Maria; Perrone, Mara; Margiotta, Nicola; Cutrignelli, Annalisa; Jung, Jae Ho; Park, Do Dam; Moon, Byung Seok; Denora, Nunzio; Kim, Sang Eun; Lee, Byung Chul

    2016-01-01

    The 18-kDa translocator protein (TSPO) levels are associated with brain, breast, and prostate cancer progression and have emerged as viable targets for cancer therapy and imaging. In order to develop highly selective and active ligands with a high affinity for TSPO, imidazopyridine-based TSPO ligand (CB256, 3) was prepared as the precursor. 99mTc- and Re-CB256 (1 and 2, respectively) were synthesized in high radiochemical yield (74.5% ± 6.4%, decay-corrected, n = 5) and chemical yield (65.6%) by the incorporation of the [99mTc(CO)3(H2O)3]+ and (NEt4)2[Re(CO)3Br3] followed by HPLC separation. Radio-ligand 1 was shown to be stable (>99%) when incubated in human serum for 4 h at 37 °C with a relatively low lipophilicity (logD = 2.15 ± 0.02). The rhenium-185 and -187 complex 2 exhibited a moderate affinity (Ki = 159.3 ± 8.7 nM) for TSPO, whereas its cytotoxicity evaluated on TSPO-rich tumor cell lines was lower than that observed for the precursor. In vitro uptake studies of 1 in C6 and U87-MG cells for 60 min was found to be 9.84% ± 0.17% and 7.87% ± 0.23% ID, respectively. Our results indicated that 99mTc-CB256 can be considered as a potential new TSPO-rich cancer SPECT imaging agent and provides the foundation for further in vivo evaluation. PMID:27399688

  9. Effective photo-enhancement of cellular activity of fluorophore-octaarginine antisense PNA conjugates correlates with singlet oxygen formation, endosomal escape and chromophore lipophilicity

    DEFF Research Database (Denmark)

    Yarani, Reza; Shiraishi, Takehiko; Nielsen, Peter E.

    2018-01-01

    Photochemical internalization (PCI) is a cellular drug delivery method based on the generation of light-induced reactive oxygen species (ROS) causing damage to the endosomal membrane and thereby resulting in drug release to the cytoplasm. In our study a series of antisense fluorophore octaarginin...... indicate that efficient photodynamic endosomal escape is strongly dependent on the quantum yield for photochemical singlet oxygen formation, photostability as well as the lipophilicity of the chromophore....

  10. A turn-on near-infrared fluorescent chemosensor for selective detection of lead ions based on a fluorophore-gold nanoparticle assembly.

    Science.gov (United States)

    Wang, Shaozhen; Sun, Junyong; Gao, Feng

    2015-06-21

    A turn-on fluorescent chemosensor of Pb(2+) in the near-infrared (NIR) region, which is based on the Pb(2+)-tuned restored fluorescence of a weakly fluorescent fluorophore-gold nanoparticle (AuNPs) assembly, has been reported. In this fluorophore-AuNP assembly, NIR fluorescent dye brilliant cresyl blue (BCB) molecules act as fluorophores and are used for signal transduction of fluorescence, while AuNPs act as quenchers to quench the nearby fluorescent BCB molecules via electron transfer. In the presence of Pb(2+), fluorescent BCB molecules detached from AuNPs and restored their fluorescence due to the formation of a chelating complex between Pb(2+) and glutathione confined on AuNPs. Under the optimal conditions, the present BCB-AuNP assembly is capable of detecting Pb(2+) with a concentration ranging from 7.5 × 10(-10) to 1 × 10(-8) mol L(-1) (0.16-2.1 ng mL(-1)) and a detection limit of 0.51 nM (0.11 ng mL(-1)). The present BCB-AuNP assembly can be used in aqueous media for the determination of Pb(2+) unlike common organic fluorescent reagents, and also shows advantages of NIR fluorescence spectrophotometry such as less interference, lower detection limit, and higher sensitivity. Moreover, the present method was successfully applied for the detection of Pb(2+) in water samples with satisfactory results.

  11. Synthesis of 2-phenyl- and 2,3-diphenyl-quinolin-4-carboxylic acid derivatives

    International Nuclear Information System (INIS)

    Elhadi, S. A.

    2004-09-01

    Quinolin derivatives are a group of compounds known to possess a wide range of biological activities. The chemistry of quinolines together with their corresponding aldehydes were dealt with in chapter one of this study. Special emphasis was given to the chemistry of benzaldehyde. Twenty five 2-phenyl- and 2,3-diphenyl-quinolin-4-carboxylic acid derivatives together with their corresponding intermediates were prepared in this work. Basically, the synthetic design of these compounds arise from the appropriate disconnections of the target 2-phenyl and 2,3-diphenyl-quinolin-4-carboxylic acids. The retro synthesis analysis of these compounds reveals pyruvic acid, aromatic amine and benzaldehyde or phenyl pyruvic acid, aromatic amine and benzaldehyde as possible logical precursors for 2-phenyl-and 2,3-diphenyl- quinoline-4-carboxylic acids respectively. The purity and identities of the synthesized compounds were elucidated through chromatographic and spectroscopic techniques. The compounds were heavily subjected to spectroscopic analysis (UV, IR, GC/MS, 1 H-and 13 C- NMR). The appropriate disconnections and the mechanisms of the corresponding reactions were given and discussed in chapter three. The spectral data were interpreted and correlated with the target structures. The prepared 2-phenyl- and 2,3-diphenyl-quinoline-4-carboxylic acid derivatives were screened for their antibacterial activity. The compounds were tested against the standard bacterial organisms B. subtilis, S. aureus, E. coli and P. vulgaris. Some of these compounds were devoid of antibacterial activity against S. aureus and P. vulgaris, while others showed moderate activity. All of the tested compounds showed an activity against B. subtilis and E. coli. 2,3-diphenyl -6-sulphanilamide-quinolin-4-carboxylic acid showed the highest activity against the four standard tested organisms.(Author)

  12. Synthesis of 2-phenyl- and 2,3-diphenyl-quinolin-4-carboxylic acid derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Elhadi, S A [Department of Chemistry, Faculty of Education, University of Khartoum, Khartoum (Sudan)

    2004-09-01

    Quinolin derivatives are a group of compounds known to possess a wide range of biological activities. The chemistry of quinolines together with their corresponding aldehydes were dealt with in chapter one of this study. Special emphasis was given to the chemistry of benzaldehyde. Twenty five 2-phenyl- and 2,3-diphenyl-quinolin-4-carboxylic acid derivatives together with their corresponding intermediates were prepared in this work. Basically, the synthetic design of these compounds arise from the appropriate disconnections of the target 2-phenyl and 2,3-diphenyl-quinolin-4-carboxylic acids. The retro synthesis analysis of these compounds reveals pyruvic acid, aromatic amine and benzaldehyde or phenyl pyruvic acid, aromatic amine and benzaldehyde as possible logical precursors for 2-phenyl-and 2,3-diphenyl- quinoline-4-carboxylic acids respectively. The purity and identities of the synthesized compounds were elucidated through chromatographic and spectroscopic techniques. The compounds were heavily subjected to spectroscopic analysis (UV, IR, GC/MS, {sup 1}H-and {sup 13}C- NMR). The appropriate disconnections and the mechanisms of the corresponding reactions were given and discussed in chapter three. The spectral data were interpreted and correlated with the target structures. The prepared 2-phenyl- and 2,3-diphenyl-quinoline-4-carboxylic acid derivatives were screened for their antibacterial activity. The compounds were tested against the standard bacterial organisms B. subtilis, S. aureus, E. coli and P. vulgaris. Some of these compounds were devoid of antibacterial activity against S. aureus and P. vulgaris, while others showed moderate activity. All of the tested compounds showed an activity against B. subtilis and E. coli. 2,3-diphenyl -6-sulphanilamide-quinolin-4-carboxylic acid showed the highest activity against the four standard tested organisms.(Author)

  13. Degradation of 4-chloro 2-aminophenol using combined strategies based on ultrasound, photolysis and ozone.

    Science.gov (United States)

    Barik, Arati J; Gogate, Parag R

    2016-01-01

    The present work investigates the degradation of 4-chloro 2-aminophenol (4C2AP), a highly toxic organic compound, using ultrasonic reactors and combination of ultrasound with photolysis and ozonation for the first time. Two types of ultrasonic reactors viz. ultrasonic horn and ultrasonic bath operating at frequency of 20 kHz and 36 kHz respectively have been used in the work. The effect of initial pH, temperature and power dissipation of the ultrasonic horn on the degradation rate has been investigated. The established optimum parameters of initial pH as 6 (natural pH of the aqueous solution) and temperature as 30 ± 2°C were then used in the degradation studies using the combined approaches. Kinetic study revealed that degradation of 4C2AP followed first order kinetics for all the treatment approaches investigated in the present work. It has been established that US+UV+O3 combined process was the most promising method giving maximum degradation of 4C2AP in both ultrasonic horn (complete removal) and bath (89.9%) with synergistic index as 1.98 and 1.29 respectively. The cavitational yield of ultrasonic bath was found to be eighteen times higher as compared to ultrasonic horn implying that configurations with higher overall areas of transducers would be better selection for large scale treatment. Overall, the work has clearly demonstrated that combined approaches could synergistically remove the toxic pollutant (4C2AP). Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Biotransformation of trans-1-chloro-3,3,3-trifluoropropene (trans-HCFO-1233zd)

    International Nuclear Information System (INIS)

    Schmidt, Tobias; Bertermann, Rüdiger; Rusch, George M.; Tveit, Ann; Dekant, Wolfgang

    2013-01-01

    trans-1-Chloro-3,3,3-trifluoropropene (trans-HCFO-1233zd) is a novel foam blowing and precision cleaning agent with a very low impact for global warming and ozone depletion. trans-HCFO-1233zd also has a low potential for toxicity in rodents and is negative in genotoxicity testing. The biotransformation of trans-HCFO-1233zd and kinetics of metabolite excretion with urine were assessed in vitro and in animals after inhalation exposures. For in vitro characterization, liver microsomes from rats, rabbits and humans were incubated with trans-HCFO-1233zd. Male Sprague Dawley rats and female New Zealand White rabbits were exposed to 2,000, 5,000 and 10,000 ppm for 6 h and urine was collected for 48 h after the end of the exposure. Study specimens were analyzed for metabolites using 19 F NMR, LC-MS/MS and GC/MS. S-(3,3,3-trifluoro-trans-propenyl)-glutathione was identified as predominant metabolite of trans-HCFO-1233zd in all microsomal incubation experiments in the presence of glutathione. Products of the oxidative biotransformation of trans-HCFO-1233zd were only minor metabolites when glutathione was present. In rats, both 3,3,3-trifluorolactic acid and N-acetyl-(3,3,3-trifluoro-trans-propenyl)-L-cysteine were observed as major urinary metabolites. 3,3,3-Trifluorolactic acid was not detected in the urine of rabbits. Quantitation showed rapid excretion of both metabolites in both species (t 1/2 1/2 < 6 h). ► Glutathione adduct as predominant in vitro metabolite in all tested species. ► Toxic metabolites could not be detected in any great extent

  15. Effects of diphenyl and p-chloro-diphenyl diselenides on feeding behavior of rats.

    Science.gov (United States)

    Bortolatto, Cristiani F; Heck, Suélen O; Gai, Bibiana M; Zborowski, Vanessa A; Neto, José S S; Nogueira, Cristina W

    2015-07-01

    The searching for safe and effective antiobesity drugs has been the subject of intense research. Previous studies have shown several pharmacological applications of organoselenium compounds; however, their possible anorectic-like actions have not been investigated. This study aims to investigate the effects of (PhSe)2 and (p-ClPhSe)2 on feeding behavior of rats and their potential as weight-reducing agents. The effects of intraperitoneal administration of diselenides were investigated through the microstructural pattern of feeding behavior, behavioral satiety sequence (BSS), hypothalamic serotonin (5-HT) uptake, body weight, and epididymal fat content of male rats. Our findings demonstrated that food intake of fasted rats was reduced by both diselenides (1 and 10 mg/kg). Diphenyl diselenide [(PhSe)2] (1 mg/kg) and p-chloro-diphenyl diselenide [(p-ClPhSe)2] (10 mg/kg) decreased the frequency, mean duration, and mean size of meals compared with the control treatment. The BSS structure was preserved when organoselenium compounds (1 mg/kg) were administered, and it was associated to a displacement to the left when the resting period started indicating a satiating action. Inhibition of 5-HT uptake in the hypothalamus (∼20 %) was also found in rats treated with low doses of (PhSe)2 and (p-ClPhSe)2 (1 mg/kg). Treatments with a high dose of both diselenides (10 mg/kg) carried out for 7 days induced weight loss and epididymal fat reduction in sated rats. This study suggests that diselenides caused a satiating action in rats that could be partially explained by the inhibition of hypothalamic 5-HT uptake. These organoselenium compounds were potential weight-reducing agents when repeatedly administered.

  16. Measurement of fluorophore concentrations and fluorescence quantum yield in tissue-simulating phantoms using three diffusion models of steady-state spatially resolved fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Diamond, Kevin R; Farrell, Thomas J; Patterson, Michael S [Department of Medical Physics, Juravinski Cancer Centre and McMaster University, 699 Concession Street, Hamilton, Ontario L8V 5C2 (Canada)

    2003-12-21

    Steady-state diffusion theory models of fluorescence in tissue have been investigated for recovering fluorophore concentrations and fluorescence quantum yield. Spatially resolved fluorescence, excitation and emission reflectance were calculated by diffusion theory and Monte Carlo simulations, and measured using a multi-fibre probe on tissue-simulating phantoms containing either aluminium phthalocyanine tetrasulfonate (AlPcS{sub 4}), Photofrin or meso-tetra-(4-sulfonatophenyl)-porphine dihydrochloride (TPPS{sub 4}). The accuracy of the fluorophore concentration and fluorescence quantum yield recovered by three different models of spatially resolved fluorescence were compared. The models were based on: (a) weighted difference of the excitation and emission reflectance, (b) fluorescence due to a point excitation source or (c) fluorescence due to a pencil beam excitation source. When literature values for the fluorescence quantum yield were used for each of the fluorophores, the fluorophore absorption coefficient (and hence concentration) at the excitation wavelengthwas recovered with a root-mean-square accuracy of 11.4% using the point source model of fluorescence and 8.0% using the more complicated pencil beam excitation model. The accuracy was calculated over a broad range of optical properties and fluorophore concentrations. The weighted difference of reflectance model performed poorly, with a root-mean-square error in concentration of about 50%. Monte Carlo simulations suggest that there are some situations where the weighted difference of reflectance is as accurate as the other two models, although this was not confirmed experimentally. Estimates of the fluorescence quantum yield in multiple scattering media were also made by determining independently from the fitted absorption spectrum and applying the various diffusion theory models. The fluorescence quantum yields for AlPcS{sub 4} and TPPS{sub 4} were calculated to be 0.59 {+-} 0.03 and 0.121 {+-} 0

  17. Measurement of fluorophore concentrations and fluorescence quantum yield in tissue-simulating phantoms using three diffusion models of steady-state spatially resolved fluorescence

    International Nuclear Information System (INIS)

    Diamond, Kevin R; Farrell, Thomas J; Patterson, Michael S

    2003-01-01

    Steady-state diffusion theory models of fluorescence in tissue have been investigated for recovering fluorophore concentrations and fluorescence quantum yield. Spatially resolved fluorescence, excitation and emission reflectance were calculated by diffusion theory and Monte Carlo simulations, and measured using a multi-fibre probe on tissue-simulating phantoms containing either aluminium phthalocyanine tetrasulfonate (AlPcS 4 ), Photofrin or meso-tetra-(4-sulfonatophenyl)-porphine dihydrochloride (TPPS 4 ). The accuracy of the fluorophore concentration and fluorescence quantum yield recovered by three different models of spatially resolved fluorescence were compared. The models were based on: (a) weighted difference of the excitation and emission reflectance, (b) fluorescence due to a point excitation source or (c) fluorescence due to a pencil beam excitation source. When literature values for the fluorescence quantum yield were used for each of the fluorophores, the fluorophore absorption coefficient (and hence concentration) at the excitation wavelengthwas recovered with a root-mean-square accuracy of 11.4% using the point source model of fluorescence and 8.0% using the more complicated pencil beam excitation model. The accuracy was calculated over a broad range of optical properties and fluorophore concentrations. The weighted difference of reflectance model performed poorly, with a root-mean-square error in concentration of about 50%. Monte Carlo simulations suggest that there are some situations where the weighted difference of reflectance is as accurate as the other two models, although this was not confirmed experimentally. Estimates of the fluorescence quantum yield in multiple scattering media were also made by determining independently from the fitted absorption spectrum and applying the various diffusion theory models. The fluorescence quantum yields for AlPcS 4 and TPPS 4 were calculated to be 0.59 ± 0.03 and 0.121 ± 0.001 respectively using the point

  18. Phenyl- and benzylurea cytokinins as competitive inhibitors of cytokinin oxidase/dehydrogenase: a structural study.

    Science.gov (United States)

    Kopecný, David; Briozzo, Pierre; Popelková, Hana; Sebela, Marek; Koncitíková, Radka; Spíchal, Lukás; Nisler, Jaroslav; Madzak, Catherine; Frébort, Ivo; Laloue, Michel; Houba-Hérin, Nicole

    2010-08-01

    Cytokinin oxidase/dehydrogenase (CKO) is a flavoenzyme, which irreversibly degrades the plant hormones cytokinins and thereby participates in their homeostasis. Several synthetic cytokinins including urea derivatives are known CKO inhibitors but structural data explaining enzyme-inhibitor interactions are lacking. Thus, an inhibitory study with numerous urea derivatives was undertaken using the maize enzyme (ZmCKO1) and the crystal structure of ZmCKO1 in a complex with N-(2-chloro-pyridin-4-yl)-N'-phenylurea (CPPU) was solved. CPPU binds in a planar conformation and competes for the same binding site with natural substrates like N(6)-(2-isopentenyl)adenine (iP) and zeatin (Z). Nitrogens at the urea backbone are hydrogen bonded to the putative active site base Asp169. Subsequently, site-directed mutagenesis of L492 and E381 residues involved in the inhibitor binding was performed. The crystal structures of L492A mutant in a complex with CPPU and N-(2-chloro-pyridin-4-yl)-N'-benzylurea (CPBU) were solved and confirm the importance of a stacking interaction between the 2-chloro-4-pyridinyl ring of the inhibitor and the isoalloxazine ring of the FAD cofactor. Amino derivatives like N-(2-amino-pyridin-4-yl)-N'-phenylurea (APPU) inhibited ZmCKO1 more efficiently than CPPU, as opposed to the inhibition of E381A/S mutants, emphasizing the importance of this residue for inhibitor binding. As highly specific CKO inhibitors without undesired side effects are of major interest for physiological studies, all studied compounds were further analyzed for cytokinin activity in the Amaranthus bioassay and for binding to the Arabidopsis cytokinin receptors AHK3 and AHK4. By contrast to CPPU itself, APPU and several benzylureas bind only negligibly to the receptors and exhibit weak cytokinin activity. Copyright 2010 Elsevier Masson SAS. All rights reserved.

  19. Real-time fluorescence assay of alkaline phosphatase in living cells using boron-doped graphene quantum dots as fluorophores.

    Science.gov (United States)

    Chen, Li; Yang, Guancao; Wu, Ping; Cai, Chenxin

    2017-10-15

    This work reports a convenient and real-time assay of alkaline phosphatase (ALP) in living cells based on a fluorescence quench-recovery process at a physiological pH using the boron-doped graphene quantum dots (BGQDs) as fluorophore. The fluorescence of BGQDs is found to be effectively quenched by Ce 3+ ions because of the coordination of Ce 3+ ions with the carboxyl group of BGQDs. Upon addition of adenosine triphosphate (ATP) into the system, the quenched fluorescence can be recovered by the ALP-positive expressed cells (such as MCF-7 cells) due to the removal of Ce 3+ ions from BGQDs surface by phosphate ions, which are generated from ATP under catalytic hydrolysis of ALP that expressed in cells. The extent of fluorescence signal recovery depends on the level of ALP in cells, which establishes the basis of ALP assay in living cells. This approach can also be used for specific discrimination of the ALP expression levels in different type of cells and thus sensitive detection of those ALP-positive expressed cells (for example MCF-7 cells) at a very low abundance (10±5 cells mL -1 ). The advantages of this approach are that it has high sensitivity because of the significant suppression of the background due to the Ce 3+ ion quenching the fluorescence of BGQDs, and has the ability of avoiding false signals arising from the nonspecific adsorption of non-target proteins because it operates via a fluorescence quench-recovery process. In addition, it can be extended to other enzyme systems, such as ATP-related kinases. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Excited-state intramolecular proton transfer (ESIPT) inspired azole-quinoline based fluorophores: Synthesis and photophysical properties study

    Energy Technology Data Exchange (ETDEWEB)

    Padalkar, Vikas S.; Sekar, Nagaiyan, E-mail: n.sekar@ictmumbai.edu.in

    2014-11-15

    7-Hydroxy-3-(4-nitrophenyl)quinoline-6-carboxylic acid was obtained by the condensation reaction of p-amino salicylic acid and 4-nitrophenylmalonadialdehyde which was obtained from phenylacetonitrile through nitration, hydrolysis and Vilsmeier reaction. 7-Hydroxy-3-(4-nitrophenyl) quinoline-6-carboxylic acid was condensed with different o-aminophenols or o-aminothiophenol in ethanol in the presence of phosphorustrichloride. Synthesized quinoline contained benzimidazole and benzothiazole moieties. Photophysical behaviors of these compounds in solvents of different polarities were studied using UV–vis and fluorescence spectroscopy. The compounds showed single absorption in all the studied solvents. The dual emissions (normal emission and ESIPT emission) as well as large Stokes' shift emission pattern were observed for the synthesized fluorophores. The photophysical study shows that the emission properties of the compounds depend on the solvent polarity. The photophysical properties of the compounds were compared with structurally analogous ESIPT quinoline. Thermal stability of the compounds was studied using thermogravimetric analysis and results show that compounds are thermally stable up to 300 °C. The synthesized quinoline derivatives were characterized using elemental analysis, FT-IR and {sup 1}H –NMR, {sup 13}C –NMR spectroscopy and mass spectral analysis. - Highlights: • First and unique study of quinoline derivatives contain ESIPT azole unit at 6-position and hydroxyl group at 7-position. • Compounds are fluorescent with considerable quantum yields. • All compounds showed absorption in ultraviolet region and emission in visible region with large Stokes' shift. • The photophysical properties of new compounds were compared with reported ESIPT quinoline analogous.

  1. Optical Sensing of Aromatic Amino Acids and Dipeptides by a Crown-Ether-Functionalized Perylene Bisimide Fluorophore.

    Science.gov (United States)

    Weißenstein, Annike; Saha-Möller, Chantu R; Würthner, Frank

    2018-06-04

    The host-guest binding properties of a fluorescent perylene bisimide (PBI) receptor equipped with crown ether were studied in detail with a series of aromatic amino acids and dipeptides by UV/Vis, fluorescence and NMR spectroscopy. Fluorescence titration experiments showed that electron-rich aromatic amino acids and dipeptides strongly quench the fluorescence of the electron-poor PBI host molecule. Benesi-Hildebrand plots of fluorescence titration data confirmed the formation of host-guest complexes with 1:2 stoichiometry. Binding constants determined by global analysis of UV/Vis and fluorescence titration experiments revealed values between 10 3  m -1 and 10 5  m -1 in acetonitrile/methanol (9:1) at 23 °C. These data showed that amino acid l-Trp having an indole group and dipeptides containing this amino acid bind to the PBI receptor more strongly than other amino acids and dipeptides investigated here. For dipeptides containing l-Trp or l-Tyr, the binding strength is dependent on the distance between the ammonium group and the aromatic unit of the amino acids and dipeptides leading to a strong sensitivity for Ala-Trp dipeptide. 1D and 2D NMR experiments also corroborated 1:2 host-guest complexation and indicated formation of two diastereomeric species of host-guest complexes. The studies have shown that a properly functionalized PBI fluorophore functions as a molecular probe for the optical sensing of aromatic amino acids and dipeptides. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Rational Design of in Vivo Tau Tangle-Selective Near-Infrared Fluorophores: Expanding the BODIPY Universe.

    Science.gov (United States)

    Verwilst, Peter; Kim, Hye-Ri; Seo, Jinho; Sohn, Nak-Won; Cha, Seung-Yun; Kim, Yeongmin; Maeng, Sungho; Shin, Jung-Won; Kwak, Jong Hwan; Kang, Chulhun; Kim, Jong Seung

    2017-09-27

    The elucidation of the cause of Alzheimer's disease remains one of the greatest questions in neurodegenerative research. The lack of highly reliable low-cost sensors to study the structural changes in key proteins during the progression of the disease is a contributing factor to this lack of insight. In the current work, we describe the rational design and synthesis of two fluorescent BODIPY-based probes, named Tau 1 and Tau 2. The probes were evaluated on the molecular surface formed by a fibril of the PHF6 ( 306 VQIVYK 311 ) tau fragment using molecular docking studies to provide a potential molecular model to rationalize the selectivity of the new probes as compared to a homologous Aβ-selective probe. The probes were synthesized in a few steps from commercially available starting products and could thus prove to be highly cost-effective. We demonstrated the excellent photophysical properties of the dyes, such as a large Stokes shift and emission in the near-infrared window of the electromagnetic spectrum. The probes demonstrated a high selectivity for self-assembled microtubule-associated protein tau (Tau protein), in both solution and cell-based experiments. Moreover, the administration to an acute murine model of tauopathy clearly revealed the staining of self-assembled hyperphosphorylated tau protein in pathologically relevant hippocampal brain regions. Tau 1 demonstrated efficient blood-brain barrier penetrability and demonstrated a clear selectivity for tau tangles over Aβ plaques, as well as the capacity for in vivo imaging in a transgenic mouse model. The current work could open up avenues for the cost-effective monitoring of the tau protein aggregation state in animal models as well as tissue staining. Furthermore, these fluorophores could serve as the basis for the development of clinically relevant sensors, for example based on PET imaging.

  3. ChloroSSRdb: a repository of perfect and imperfect chloroplastic simple sequence repeats (cpSSRs) of green plants.

    Science.gov (United States)

    Kapil, Aditi; Rai, Piyush Kant; Shanker, Asheesh

    2014-01-01

    Simple sequence repeats (SSRs) are regions in DNA sequence that contain repeating motifs of length 1-6 nucleotides. These repeats are ubiquitously present and are found in both coding and non-coding regions of genome. A total of 534 complete chloroplast genome sequences (as on 18 September 2014) of Viridiplantae are available at NCBI organelle genome resource. It provides opportunity to mine these genomes for the detection of SSRs and store them in the form of a database. In an attempt to properly manage and retrieve chloroplastic SSRs, we designed ChloroSSRdb which is a relational database developed using SQL server 2008 and accessed through ASP.NET. It provides information of all the three types (perfect, imperfect and compound) of SSRs. At present, ChloroSSRdb contains 124 430 mined SSRs, with majority lying in non-coding region. Out of these, PCR primers were designed for 118 249 SSRs. Tetranucleotide repeats (47 079) were found to be the most frequent repeat type, whereas hexanucleotide repeats (6414) being the least abundant. Additionally, in each species statistical analyses were performed to calculate relative frequency, correlation coefficient and chi-square statistics of perfect and imperfect SSRs. In accordance with the growing interest in SSR studies, ChloroSSRdb will prove to be a useful resource in developing genetic markers, phylogenetic analysis, genetic mapping, etc. Moreover, it will serve as a ready reference for mined SSRs in available chloroplast genomes of green plants. Database URL: www.compubio.in/chlorossrdb/ © The Author(s) 2014. Published by Oxford University Press.

  4. 3,5-Bis(4-meth-oxy-phen-yl)-1-phenyl-4,5-dihydro-1H-pyrazole.

    Science.gov (United States)

    Baktır, Zeliha; Akkurt, Mehmet; Samshuddin, S; Narayana, B; Yathirajan, H S

    2011-01-12

    In the title compound, C(23)H(22)N(2)O(2), the central pyrazole ring is nearly planar (r.m.s. deviation = 0.046 Å) and it makes a dihedral angle of 18.5 (2)° with the phenyl ring. The dihedral angles between the phenyl and the two meth-oxy-substituted phenyl rings are 26.2 (2) and 80.6 (2)°. The crystal structure is stabilized by C-H⋯π stacking inter-actions and weak π-π inter-actions [centriod-centroid distance = 3.891 (2) Å].

  5. Some Anilides of 2-Alkylthio- and 2-Chloro-6-Alkylthio-4-Pyridinecarboxylic Acids: Synthesis and Photosynthesis-Inhibiting Activity

    Directory of Open Access Journals (Sweden)

    Miloš Macháček

    2001-06-01

    Full Text Available Many compounds containing a -CONH- group display photosynthesis inhibiting activity. Based on this structural feature, a group of anilides of 2-alkylthio-(1b-4f or 2-chloro-6-alkylthio-4-pyridinecarboxylic acids (5a-6c was synthesised. The prepared compounds were tested for their inhibition of the oxygen evolution rate (OER in spinach chloroplasts. A quasi-parabolic dependence between photosynthesis-inhibiting activity and the lipophilicity of the compounds was determined for 1b-4f as well as for 5a-6c. The inhibitory activity of compounds 1b-4f was higher than that of 5a-6c for comparable lipophilicity values.

  6. Reduction of 2-chloro-N-phenylpropanamide and 2-methyl-N-phenylaziridine with lithium aluminium hydride

    DEFF Research Database (Denmark)

    Vilhelmsen, Mie Højer; Østergaard, Lars Frøsig; Nielsen, Mogens Brøndsted

    2008-01-01

    in the reduction and can be isolated from reactions with less LiAlH4. Reduction of 2-methyl-N-phenylaziridine itself proceeds non-regioselectively to provide a mixture of propyl- and isopropylanilines. Formation of the amines by reduction of the aziridine is much slower than formation by reduction of the 2......-chloropropanamide, which indicates that Lewis acid catalysis (by aluminium chlorohydrides) facilitates the reduction of the aziridine. In addition, Lewis acid catalysis increases the relative yield of the propylamine product. The reduction of 2-chloro-N-phenylpropanamide furnishes 2-phenylamino-1-propanol as a by...

  7. One-step versus two-step mechanism of Diels-Alder reaction of 1-chloro-1-nitroethene with cyclopentadiene and furan.

    Science.gov (United States)

    Jasiński, Radomir

    2017-08-01

    DFT computational study shows that Diels-Alder (DA) reactions of 1-chloro-1-nitroethene with cyclopentadiene and furan have polar nature. However, their mechanism is substantially different. In particular, 1-chloro-1-nitroethene react with cyclopentadiene according to one-step mechanism. In the same time, more favourable channel associated with the P-DA reaction between furan and 1-chloro-1-nitroethene is a domino process, that comprises an initial hetero-Diels-Alder reaction yielding a [2+4] cycloadduct, which experiences a subsequent [3,3] sigmatropic shift to yield the expected formal [4+2] cycloadduct. This is a consequence of more polar nature of reaction, due to higher nucleophilicity of furan in comparison to cyclopentadiene. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Effective Biotransformation of Ethyl 4-Chloro-3-Oxobutanoate into Ethyl (S)-4-Chloro-3-Hydroxybutanoate by Recombinant E. coli CCZU-T15 Whole Cells in [ChCl][Gly]-Water Media.

    Science.gov (United States)

    Dai, Yong; Huan, Bin; Zhang, Hai-Sheng; He, Yu-Cai

    2017-04-01

    To increase the biocatalytic activity of Escherichia coli CCZU-T15 whole cells, choline chloride/glycerol ([ChCl][Gly]) was firstly used as biocompatible solvent for the effective biotransformation of ethyl 4-chloro-3-oxobutanoate (COBE) into ethyl (S)-4-chloro-3-hydroxybutanoate [(S)-CHBE]. Furthermore, L-glutamine (150 mM) was added into [ChCl][Gly]-water ([ChCl][Gly] 12.5 vol%, pH 6.5) media instead of NAD + for increasing the biocatalytic efficiency. To further improve the biosynthesis of (S)-CHBE (>99 % e.e.) by E. coli CCZU-T15 whole cells, Tween-80 (7.5 mM) was also added into this reaction media, and (S)-CHBE (>9 % e.e.) could be effectively synthesized from 2000 and 3000 mM COBE in the yields of 100 and 93.0 % by whole cells of recombinant E. coli CCZU-T15, respectively. TEM image indicated that the cell membrane was permeabilized and lost its integrity and when the cell was exposed to [ChCl][Gly]-water media with Tween-80. Clearly, this bioprocess has high potential for the effective biosynthesis of (S)-CHBE (>99 % e.e.).

  9. Synthesis of the enantiomers of [3-{sup 3}H]-2-[[4-[(7-chloro-4-quinolinyl)-amino]pentyl]ethylamino]eth anol, [3-{sup 3}H]-hydroxychloroquine

    Energy Technology Data Exchange (ETDEWEB)

    Ellames, G.J.; Herbert, J.M.; Peace, J.E.; Smith, D.J.; Wedge, K.J. [Sterling Winthrop Research Centre, Alnwick (United Kingdom). Pharmaceuticals Research Div.

    1995-01-01

    The enantiomers of [3-{sup 3}H]-2-[[4-[(7-chloro-4-quinolinyl)amino] pentyl]ethylamino]ethanol, [3-{sup 3}H]-hydroxychloroquine, (R)-8 and (S)-8, have been prepared in two steps from the known precursors 4,7-dichloro-3-iodoquinoline, and the enantiomers of 2-[(4-aminopentyl) ethyl-amino]ethanol, (R)-2 and (S)-2, by formation of the enantiomers of 2-[[4-[(7-chloro-3-iodo-4-quinolinyl)amino]pentyl]ethylamino] ethanol, (R)-3 and (S)-3, and subsequent reductive deiodination with tritium gas over 10% palladium on charcoal. (Author).

  10. Synthesis of the enantiomers of [3-3H]-2-[[4-[(7-chloro-4-quinolinyl)-amino]pentyl]ethylamino]eth anol, [3-3H]-hydroxychloroquine

    International Nuclear Information System (INIS)

    Ellames, G.J.; Herbert, J.M.; Peace, J.E.; Smith, D.J.; Wedge, K.J.

    1995-01-01

    The enantiomers of [3- 3 H]-2-[[4-[(7-chloro-4-quinolinyl)amino] pentyl]ethylamino]ethanol, [3- 3 H]-hydroxychloroquine, (R)-8 and (S)-8, have been prepared in two steps from the known precursors 4,7-dichloro-3-iodoquinoline, and the enantiomers of 2-[(4-aminopentyl) ethyl-amino]ethanol, (R)-2 and (S)-2, by formation of the enantiomers of 2-[[4-[(7-chloro-3-iodo-4-quinolinyl)amino]pentyl]ethylamino] ethanol, (R)-3 and (S)-3, and subsequent reductive deiodination with tritium gas over 10% palladium on charcoal. (Author)

  11. 1-[(Oxiran-2-ylmethyl]-3-phenyl-1,2-dihydroquinoxalin-2-one

    Directory of Open Access Journals (Sweden)

    Nadeem Abad

    2018-04-01

    Full Text Available The asymmetric unit of the title compound, C17H14N2O2, consists of two independent molecules differing mainly in the orientations of the phenyl and oxirane substituents. In the first molecule, the dihedral angle between the dihydroquinoxaline ring system and phenyl ring is 28.4 (2° and the N—C—C—O torsion angle is 87.8 (5°; corresponding data for the second molecule are 23.1 (2 and −85.6 (5°, respectively. In the crystal, offset π-stacking interactions between the dihydroquinoxaline moieties form oblique stacks, which are connected into layers parallel to the bc plane by C—H...O hydrogen bonds and C—H...π(ring interactions. Additional C—H...π(ring interactions tie the layers together. The model was refined as a two-component twin.

  12. Biotransformation of trans-1-chloro-3,3,3-trifluoropropene (trans-HCFO-1233zd)

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Tobias [Institut für Toxikologie, Universität Würzburg, Versbacher Str. 9, 97078 Würzburg (Germany); Bertermann, Rüdiger [Institut für Anorganische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg (Germany); Rusch, George M.; Tveit, Ann [Honeywell, P.O. Box 1057, Morristown, NJ 07962-1057 (United States); Dekant, Wolfgang, E-mail: dekant@toxi.uni-wuerzburg.de [Institut für Toxikologie, Universität Würzburg, Versbacher Str. 9, 97078 Würzburg (Germany)

    2013-05-01

    trans-1-Chloro-3,3,3-trifluoropropene (trans-HCFO-1233zd) is a novel foam blowing and precision cleaning agent with a very low impact for global warming and ozone depletion. trans-HCFO-1233zd also has a low potential for toxicity in rodents and is negative in genotoxicity testing. The biotransformation of trans-HCFO-1233zd and kinetics of metabolite excretion with urine were assessed in vitro and in animals after inhalation exposures. For in vitro characterization, liver microsomes from rats, rabbits and humans were incubated with trans-HCFO-1233zd. Male Sprague Dawley rats and female New Zealand White rabbits were exposed to 2,000, 5,000 and 10,000 ppm for 6 h and urine was collected for 48 h after the end of the exposure. Study specimens were analyzed for metabolites using {sup 19}F NMR, LC-MS/MS and GC/MS. S-(3,3,3-trifluoro-trans-propenyl)-glutathione was identified as predominant metabolite of trans-HCFO-1233zd in all microsomal incubation experiments in the presence of glutathione. Products of the oxidative biotransformation of trans-HCFO-1233zd were only minor metabolites when glutathione was present. In rats, both 3,3,3-trifluorolactic acid and N-acetyl-(3,3,3-trifluoro-trans-propenyl)-L-cysteine were observed as major urinary metabolites. 3,3,3-Trifluorolactic acid was not detected in the urine of rabbits. Quantitation showed rapid excretion of both metabolites in both species (t{sub 1/2} < 6 h) and the extent of biotransformation of trans-HCFO-1233zd was determined as approximately 0.01% of received dose in rabbits and approximately 0.002% in rats. trans-HCFO-1233zd undergoes both oxidative biotransformation and glutathione conjugation at very low rates. The low extent of biotransformation and the rapid excretion of metabolites formed are consistent with the very low potential for toxicity of trans-HCFO-1233zd in mammals. - Highlights: ► No lethality and clinical signs were observed. ► Glutathione S-transferase and cytochrome P-450 dependent

  13. Disposition of inhaled 1-chloro-2-propanol in F344/N rats

    International Nuclear Information System (INIS)

    Bond, J.A.; Birnbaum, L.S.; Dahl, A.R.; Medinsky, M.A.; Sabourin, P.J.; Henderson, R.F.

    1988-01-01

    Propylene chlorohydrins, of which 1-chloro-2-propanol (1-CP) is a constituent, used as intermediates in the manufacture of propylene oxide and have been identified as potential air pollutants. The objective of these studies was to determine whether changes in the inhaled exposure concentration would affect the disposition of 1-CP in rats. In addition, experiments were conducted to identify the carbon atom of 1-CP that is metabolized to CO2. Rats were exposed nose-only to [14C]1-CP for 6 hr to 8.3 +/- 1.0 ppm (26.1 +/- 3.2 micrograms/liter air) or 77 +/- 4 ppm (245 +/- 13 micrograms/liter air) (mean +/- SE). There were two major routes of elimination of 14C, urinary and exhalation of CO2, which together accounted for about 80% of the total 14C in excreta and carcass. Half-times for elimination of 14C in urine as 14CO2 were between 3 and 7 hr with no effect of exposure concentration on the elimination half-times for either route. After the end of exposure, kidneys, livers, trachea, and nasal turbinates contained high concentrations of [14C]1-CP equivalents at both exposure concentrations (30-50 nmol 14C/g tissue for the 8 ppm exposure level and 200-350 nmol 14C/g tissue for the 80 ppm exposure level). Elimination of 14C from tissues was biphasic with about 50% of the material in a tissue being rapidly eliminated with a half-time of 1 to 3 hr and the remaining material slowly eliminated with a half-time of 40 to 80 hr. There was no effect of exposure concentration on elimination half-times in tissues. Major metabolites detected in urine and tissues (liver, kidney, and lung) were N-acetyl-S-(hydroxypropyl)cysteine and/or S-(2-hydroxypropyl)-cysteine. Little unmetabolized 1-CP (less than 1%) was detected in analyzed tissues or urine

  14. Recovery of plutonium from oxalate supernatant using 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone

    International Nuclear Information System (INIS)

    Mohapatra, P.K.; Manchanda, V.K.; Gupta, K.K.; Singh, R.K.

    1997-01-01

    Extraction of Pu(IV) from oxalate supernatant was carried out employing varying concentrations of 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP). Near quantitative extraction of Pu(IV) from an aqueous solution of 0.2M oxalic acid and 3M HNO 3 was possible employing 0.05M PMBP solution in xylene. Extraction studies at different uranium loading conditions were carried out and conditions for quantitative stripping were arrived at. (author). 2 refs., 4 tabs

  15. An improved synthesis of 2,2−-((4-substituted phenyl methylene difurans by Ultrasound irradiation

    Directory of Open Access Journals (Sweden)

    Naween M. Yonis

    2016-09-01

    Full Text Available A new series of 2,2−((4-substituted phenyl methylene difuran was synthesized by one-pot cyclocondensation of aldehyde with excess furan at room temperature using trifluoro acetic acid as a catalyst under ultrasound irradiation in the absence of solvent. The products were compared with the classical condensation reactions. This method consistently enjoys the advantages of mild reaction conditions, excellent yields, easy work up and short time.

  16. Phenyl thiazolyl urea and carbamate derivatives as new inhibitors of bacterial cell-wall biosynthesis.

    Science.gov (United States)

    Francisco, Gerardo D; Li, Zhong; Albright, J Donald; Eudy, Nancy H; Katz, Alan H; Petersen, Peter J; Labthavikul, Pornpen; Singh, Guy; Yang, Youjun; Rasmussen, Beth A; Lin, Yang-I; Mansour, Tarek S

    2004-01-05

    Over 50 phenyl thiazolyl urea and carbamate derivatives were synthesized for evaluation as new inhibitors of bacterial cell-wall biosynthesis. Many of them demonstrated good activity against MurA and MurB and gram-positive bacteria including MRSA, VRE and PRSP. 3,4-Difluorophenyl 5-cyanothiazolylurea (3p) with clog P of 2.64 demonstrated antibacterial activity against both gram-positive and gram-negative bacteria.

  17. New phenyl-ethanediols from the culture broth of Boletus edulis.

    Science.gov (United States)

    Yang, Wan-Qiu; Qin, Xiang-Dong; Shao, Hong-Jun; Fang, Li-Zhen; Wang, Fei; Ding, Zhi-Hui; Dong, Ze-Jun; Liu, Ji-Kai

    2007-04-01

    A new phenyl-ethanediol, (1S)-(4-acetylphenyl)-1, 2-ethanediol (1), and a new natural product, (1S)-(3-ethenylphenyl)-1, 2-ethanediol (2), were isolated from the culture broth of the basidiomycete Boletus edulis together with three related known compounds, 1-(4-ethylphenyl)-1, 2-ethanediol (3), 1-(3-ethylphenyl)-1, 2-ethanediol (4) and 1-(3-formylphenyl)-ethanone (5). Their structures were elucidated by spectroscopic methods including extensive 2D-NMR techniques.

  18. Coalescence of 3-phenyl-propynenitrile on Cu(111) into interlocking pinwheel chains

    Science.gov (United States)

    Luo, Miaomiao; Lu, Wenhao; Kim, Daeho; Chu, Eric; Wyrick, Jon; Holzke, Connor; Salib, Daniel; Cohen, Kamelia D.; Cheng, Zhihai; Sun, Dezheng; Zhu, Yeming; Einstein, T. L.; Bartels, Ludwig

    2011-10-01

    3-phenyl-propynenitrile (PPN) adsorbs on Cu(111) in a hexagonal network of molecular trimers formed through intermolecular interaction of the cyano group of one molecule with the aromatic ring of its neighbor. Heptamers of trimers coalesce into interlocking pinwheel-shaped structures that, by percolating across islands of the original trimer coverage, create the appearance of gear chains. Density functional theory aids in identifying substrate stress associated with the chemisorption of PPN's acetylene group as the cause of this transition.

  19. {2,6-Bis[(di-tert-butyl-phosphino)-methyl]-phenyl}chloridonickel(II).

    Science.gov (United States)

    Boro, Brian J; Dickie, Diane A; Goldberg, Karen I; Kemp, Richard A

    2008-09-20

    In the title compound, [Ni(C(24)H(43)P(2))Cl], the Ni atom adopts a distorted square-planar geometry, with the P atoms of the 2,6-bis-[(di-tert-butyl-phosphino)meth-yl]phenyl ligand trans to one another. The P-Ni-P plane is twisted out of the plane of the aromatic ring by 21.97 (6)°.

  20. Synthesis and properties of complexes of 1-phenyl-2,3-dimetylpyrazolone-5-thione with metals

    International Nuclear Information System (INIS)

    Bikkulova, A.T.; Kapina, A.P.; Medvedeva, E.A.

    1985-01-01

    Cadmium complexes with thiopyrine (1-phenyl-2.3-dimethylpyrazolone-5-thione) (R) of the composition CdR 2 X 2 are obtained by precipitation from hydrochloric acid solutions at pH=1 and at chloride and bromide (X) excess. The formation of coordination bond of a metal through the sulphur atom is established by the IR- and NMR-spectroscopy methods. Fungicidal activity of the compositions obtained is detected

  1. 2-[3-(4-Methoxyphenyl-1-phenyl-1H-pyrazol-5-yl]phenol

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available The title compound, C22H18N2O2, was derived from 1-(2-hydroxyphenyl-3-(4-methoxyphenylpropane-1,3-dione. The central pyrazole ring forms dihedral angles of 16.83 (5, 48.97 (4 and 51.68 (4°, respectively, with the methoxyphenyl, phenyl and hydroxyphenyl rings. The crystal packing is stabilized by O—H...N hydrogen bonding.

  2. Synthesis, Characterization and Chelating Properties of 4-Butyrylsemicarbazone-1-phenyl-3-methyl-2-pyrazolin-5-one

    Directory of Open Access Journals (Sweden)

    J. D. Patel

    2010-01-01

    Full Text Available 4-Butyrylsemicarbazone-1-phenyl-3-methyl-2-pyrazolin-5-one (BUMP-SC was prepared and its metal chelates of Cu2+, Ni2+, Co2+, Mn2+, Fe2+, Fe3+, Cr3+, UO2 and OV were prepared. The ligands and its chelates were characterized by elemental analysis, metal:ligand (M:L stoichiometry, IR-electronic spectral studies and magnetic properties. The compounds also were screened for their antimicrobial activity.

  3. Radical cation spectroscopy of substituted alkyl phenyl ketones via tunnel ionization

    Energy Technology Data Exchange (ETDEWEB)

    Bohinski, Timothy; Moore Tibbetts, Katharine [Center for Advanced Photonics Research, Temple University, Philadelphia, PA 19122 (United States); Department of Chemistry, Temple University, Philadelphia, PA 19122 (United States); Munkerup, Kristin [Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø (Denmark); Tarazkar, Maryam [Center for Advanced Photonics Research, Temple University, Philadelphia, PA 19122 (United States); Department of Chemistry, Temple University, Philadelphia, PA 19122 (United States); Romanov, Dmitri A. [Center for Advanced Photonics Research, Temple University, Philadelphia, PA 19122 (United States); Department of Physics, Temple University, Philadelphia, PA 19122 (United States); Matsika, Spiridoula [Department of Chemistry, Temple University, Philadelphia, PA 19122 (United States); Levis, Robert J., E-mail: rjlevis@temple.edu [Center for Advanced Photonics Research, Temple University, Philadelphia, PA 19122 (United States); Department of Chemistry, Temple University, Philadelphia, PA 19122 (United States)

    2014-10-17

    Highlights: • Infrared strong field spectroscopy on (o, m, p)-methylacetophenone was performed. • Electronic resonance in the radical cations at 1370 nm produces benzoyl fragment. • Magnitude of resonance feature increases from ortho to meta to para isomer. • Hydrogen interactions and moment of inertia account for the trend across isomers. - Abstract: Mass spectra are measured for 2′-, 3′- and 4′-(ortho, meta and para) methyl substituted alkyl phenyl ketones excited at wavelengths ranging from 1200 to 1500 nm in the strong field regime. The selective loss of a methyl group from the acetyl group of the parent molecular ion upon excitation at ∼1370 nm is attributed to an electronic resonance between ground D{sub 0} and excited D{sub 2} state of the radical cation. Depletion of the parent molecular ion is enhanced as the methyl substituent is moved from the 2′ to 3′ to 4′ position on the phenyl ring with respect to the acetyl group. The phenyl-acetyl dihedral angle is the relevant coordinate enabling excitation to the dissociative D{sub 2} state. Calculations on the radical cation of 2′-methylacetophenone show two stable geometries with dihedral angles of 7 degrees and 63 degrees between the phenyl and acetyl groups. The barrier to rotation for the 2′ isomer limits population transfer to the D{sub 2} state. In contrast, calculations on the radical cations of 3′- and 4′-methylacetophenone reveal no rotational barrier to prevent population transfer to the excited state, which is consistent with the enhanced dissociation yield in comparison with the 2′ substitution. The enhanced dissociation of the 4′ isomer as compared to the 3′ isomer is attributed to its lower moment of inertia about the dihedral angle.

  4. Electroplex emission from bilayer LED based on 1-phenyl-3-(dimethyl-amino) styryl-5-(p-(dimethylamino) phenyl) pyrazoline and 2,2'-(2,5-thiophenediyl) bis-(5-phenyl)-1,3,4-oxadiazole

    International Nuclear Information System (INIS)

    Zhang Zhiming; Li Guowen; Shen Jiacong; Ma Yuguang

    2003-01-01

    The photoluminescence (PL) and electroluminescence (EL) properties of a novel organic compound, 2,2'-(2,5-thiophenediyl) bis-(5-phenyl)-1,3,4-oxadiazole (TOXD), were studied as electron transporting material. The PL emission maximum peak is at 408 nm of TOXD in chloroform and is at 472 nm in solid film, respectively. The EL emission maximum peaks of the bilayer ITO/PDP/TOXD/Al LED located between emission maximum peaks of TOXD (470 nm) and PDP (500 nm) at lower driving voltage, 4.5-5.4 V, and shifted to 508 nm at 6.0 V and 518 nm at 7.0 V with increase of applied voltage. The new EL emission peak at 518 nm from the bilayer LED is ascribed to electroplex formation at the interface of TOXD and PDP film in bilayer LED under external electric field. The electroplex emission is close to the energy levels of PDP and TOXD

  5. Electroplex emission from bilayer LED based on 1-phenyl-3-(dimethyl-amino) styryl-5-(p-(dimethylamino) phenyl) pyrazoline and 2,2'-(2,5-thiophenediyl) bis-(5-phenyl)-1,3,4-oxadiazole

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Zhiming; Li Guowen; Shen Jiacong; Ma Yuguang

    2003-12-20

    The photoluminescence (PL) and electroluminescence (EL) properties of a novel organic compound, 2,2'-(2,5-thiophenediyl) bis-(5-phenyl)-1,3,4-oxadiazole (TOXD), were studied as electron transporting material. The PL emission maximum peak is at 408 nm of TOXD in chloroform and is at 472 nm in solid film, respectively. The EL emission maximum peaks of the bilayer ITO/PDP/TOXD/Al LED located between emission maximum peaks of TOXD (470 nm) and PDP (500 nm) at lower driving voltage, 4.5-5.4 V, and shifted to 508 nm at 6.0 V and 518 nm at 7.0 V with increase of applied voltage. The new EL emission peak at 518 nm from the bilayer LED is ascribed to electroplex formation at the interface of TOXD and PDP film in bilayer LED under external electric field. The electroplex emission is close to the energy levels of PDP and TOXD.

  6. Solar photoelectro-Fenton degradation of the herbicide 4-chloro-2-methylphenoxyacetic acid optimized by response surface methodology.

    Science.gov (United States)

    Garcia-Segura, Sergi; Almeida, Lucio Cesar; Bocchi, Nerilso; Brillas, Enric

    2011-10-30

    A central composite rotatable design and response surface methodology (RSM) were used to optimize the experimental variables of the solar photoelectro-Fenton (SPEF) treatment of the herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA). The experiments were made with a flow plant containing a Pt/air-diffusion reactor coupled to a solar compound parabolic collector (CPC) under recirculation of 10 L of 186 mg L(-1) MCPA solutions in 0.05 M Na(2)SO(4) at a liquid flow rate of 180 L h(-1) with an average UV irradiation intensity of about 32 Wm(-2). The optimum variables found for the SPEF process were 5.0 A, 1.0mM Fe(2+) and pH 3.0 after 120 min of electrolysis. Under these conditions, 75% of mineralization with 71% of current efficiency and 87.7 k Wh kg(-1) TOC of energy consumption were obtained. MCPA decayed under the attack of generated hydroxyl radicals following a pseudo-first-order kinetics. Hydroxyl radicals also destroyed 4-chloro-2-methylphenol, methylhydroquinone and methyl-p-benzoquinone detected as aromatic by-products. Glycolic, maleic, fumaric, malic, succinic, tartronic, oxalic and formic acids were identified as generated carboxylic acids, which form Fe(III) complexes that are quickly photodecarboxylated by the UV irradiation of sunlight at the CPC photoreactor. A reaction sequence for the SPEF degradation of MCPA was proposed. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Novel organic dyes based on phenyl-substituted benzimidazole for dye sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Saltan, Gözde Murat [Department of Chemistry, Faculty of Arts and Science, Celal Bayar University, Yunus Emre, 45140 Manisa (Turkey); Dinçalp, Haluk, E-mail: haluk.dincalp@cbu.edu.tr [Department of Chemistry, Faculty of Arts and Science, Celal Bayar University, Yunus Emre, 45140 Manisa (Turkey); Kıran, Merve; Zafer, Ceylan [Solar Energy Institute, Ege University, Bornova, 35100 Izmir (Turkey); Erbaş, Seçil Çelik [Celal Bayar University, Materials Engineering Department, Faculty of Engineering, Yunus Emre, 45140 Manisa (Turkey)

    2015-08-01

    Two new sensitizers derived from benzimidazole core for dye-sensitized solar cell (DSSC) applications were designed and synthesized as D–π–A structures, in which two phenyl-substituted benzimidazole group, a phenyl ring and a cyanoacrylic acid were used as the electron donor, π-conjugated linkage and the electron acceptor, respectively. Effect of methoxy- and N,N-dimetylamino- moieties attached to the phenyl groups of benzimidazole were investigated by means of optical and photovoltaic measurements. The compounds exhibit broad absorption maximum at 387 nm with the tail extending up to 500 nm on TiO{sub 2}-coated thin film. The longer wavelength absorption band around 360 nm and the much longer decay components could be attributed to the existence of charge transfer state of the dyes in solutions. DSSC device fabricated by using methoxy substituted dye (BI5a) as a sensitizer shows much better incident photon-to-current conversion efficiency (IPCE) of 64% giving cell efficiency of 2.68%. - Graphical abstract: Display Omitted - Highlights: • Long decay times suggest the delayed fluorescence caused by the existence of ICT. • The best solar energy conversion efficiency was obtained for BI5a dye (2.68%). • More fluorescent BI5a dye gives higher photocurrent generation.

  8. Synthesis, biological evaluation and molecular docking of N-phenyl thiosemicarbazones as urease inhibitors.

    Science.gov (United States)

    Hameed, Abdul; Khan, Khalid Mohammed; Zehra, Syeda Tazeen; Ahmed, Ramasa; Shafiq, Zahid; Bakht, Syeda Mahwish; Yaqub, Muhammad; Hussain, Mazhar; de la Vega de León, Antonio; Furtmann, Norbert; Bajorath, Jürgen; Shad, Hazoor Ahmad; Tahir, Muhammad Nawaz; Iqbal, Jamshed

    2015-08-01

    Urease is an important enzyme which breaks urea into ammonia and carbon dioxide during metabolic processes. However, an elevated activity of urease causes various complications of clinical importance. The inhibition of urease activity with small molecules as inhibitors is an effective strategy for therapeutic intervention. Herein, we have synthesized a series of 19 benzofurane linked N-phenyl semithiocarbazones (3a-3s). All the compounds were screened for enzyme inhibitor activity against Jack bean urease. The synthesized N-phenyl thiosemicarbazones had varying activity levels with IC50 values between 0.077 ± 0.001 and 24.04 ± 0.14 μM compared to standard inhibitor, thiourea (IC50 = 21 ± 0.11 μM). The activities of these compounds may be due to their close resemblance of thiourea. A docking study with Jack bean urease (PDB ID: 4H9M) revealed possible binding modes of N-phenyl thiosemicarbazones. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Optimization of lipase-catalyzed enantioselective production of 1-phenyl 1-propanol using response surface methodology.

    Science.gov (United States)

    Soyer, Asli; Bayraktar, Emine; Mehmetoglu, Ulku

    2010-01-01

    Optically active 1-phenyl 1-propanol is used as a chiral building block and synthetic intermediate in the pharmaceutical industries. In this study, the enantioselective production of 1-phenyl 1-propanol was investigated systematically using response surface methodology (RSM). Before RSM was applied, the effects of the enzyme source, the type of acyl donor, and the type of solvent on the kinetic resolution of 1-phenyl 1-propanol were studied. The best results were obtained with Candida antartica lipase (commercially available as Novozym 435), vinyl laurate as the acyl donor, and isooctane as the solvent. In the RSM, substrate concentration, molar ratio of acyl donor to the substrate, amount of enzyme, temperature, and stirring rate were chosen as independent variables. The predicted optimum conditions for a higher enantiomeric excess (ee) were as follows: substrate concentration, 233 mM; molar ratio of acyl donor to substrate, 1.5; enzyme amount, 116 mg; temperature, 47 °C; and stirring rate, 161 rpm. A verification experiment conducted at these optimized conditions for maximum ee yielded 91% for 3 hr, which is higher than the predicted value of 83%. The effect of microwave on the ee was also investigated and ee reached 87% at only 5 min.

  10. Click functionalization of phenyl-capped bithiophene on azide-terminated self-assembled monolayers

    International Nuclear Information System (INIS)

    Zheng, Yijun; Cui, Jiaxi; Ikeda, Taichi

    2015-01-01

    Graphical abstract: - Highlights: • Electrochemically-active self-assembled monolayers with phenyl-capped bithiophene were prepared. • Post-functionalization method based on click chemistry solved the solubility issue of phenyl-capped thiophene alkanethiol. • The capture and release of the counter anions during the redox reaction were detectable by E-QCM. - Abstract: We immobilized tetra(ethylene glycol)-substituted phenyl-capped bithiophene with alkyne terminals (Ph2TPh-alkyne) on azide-terminated self-assembled monolayers (N 3 -SAMs) by Cu-catalyzed azide-alkyne cycloaddition reaction. Ph2TPh-functionalized SAMs on a gold substrate showed reversible electrochemical response. The surface densities of the azide groups in N 3 -SAMs and Ph2TPh units in Ph2TPh-functionalized SAMs were estimated to be 7.3 ± 0.3 × 10 −10 mol cm −2 and 4.6 ± 0.3 × 10 −10 mol cm −2 , respectively, by quartz crystal microbalance (QCM). Most of Ph2TPh-alkynes are considered to be anchored on N 3 -SAMs via both terminal groups. Ph2TPh-functionalized SAMs exhibited reversible redox peaks in cyclic voltammetry (CV). In redox reaction, reversible capture and release of the counter anion could be monitored by electrochemical QCM (E-QCM).

  11. Click functionalization of phenyl-capped bithiophene on azide-terminated self-assembled monolayers

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Yijun; Cui, Jiaxi [Max Planck Institute for Polymer Research (MPIP), Ackermannweg 10, Mainz 55128 (Germany); Ikeda, Taichi, E-mail: IKEDA.Taichi@nims.go.jp [Max Planck Institute for Polymer Research (MPIP), Ackermannweg 10, Mainz 55128 (Germany); Polymer Materials Unit, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba 305-0044 (Japan)

    2015-11-15

    Graphical abstract: - Highlights: • Electrochemically-active self-assembled monolayers with phenyl-capped bithiophene were prepared. • Post-functionalization method based on click chemistry solved the solubility issue of phenyl-capped thiophene alkanethiol. • The capture and release of the counter anions during the redox reaction were detectable by E-QCM. - Abstract: We immobilized tetra(ethylene glycol)-substituted phenyl-capped bithiophene with alkyne terminals (Ph2TPh-alkyne) on azide-terminated self-assembled monolayers (N{sub 3}-SAMs) by Cu-catalyzed azide-alkyne cycloaddition reaction. Ph2TPh-functionalized SAMs on a gold substrate showed reversible electrochemical response. The surface densities of the azide groups in N{sub 3}-SAMs and Ph2TPh units in Ph2TPh-functionalized SAMs were estimated to be 7.3 ± 0.3 × 10{sup −10} mol cm{sup −2} and 4.6 ± 0.3 × 10{sup −10} mol cm{sup −2}, respectively, by quartz crystal microbalance (QCM). Most of Ph2TPh-alkynes are considered to be anchored on N{sub 3}-SAMs via both terminal groups. Ph2TPh-functionalized SAMs exhibited reversible redox peaks in cyclic voltammetry (CV). In redox reaction, reversible capture and release of the counter anion could be monitored by electrochemical QCM (E-QCM).

  12. Novel organic dyes based on phenyl-substituted benzimidazole for dye sensitized solar cells

    International Nuclear Information System (INIS)

    Saltan, Gözde Murat; Dinçalp, Haluk; Kıran, Merve; Zafer, Ceylan; Erbaş, Seçil Çelik

    2015-01-01

    Two new sensitizers derived from benzimidazole core for dye-sensitized solar cell (DSSC) applications were designed and synthesized as D–π–A structures, in which two phenyl-substituted benzimidazole group, a phenyl ring and a cyanoacrylic acid were used as the electron donor, π-conjugated linkage and the electron acceptor, respectively. Effect of methoxy- and N,N-dimetylamino- moieties attached to the phenyl groups of benzimidazole were investigated by means of optical and photovoltaic measurements. The compounds exhibit broad absorption maximum at 387 nm with the tail extending up to 500 nm on TiO 2 -coated thin film. The longer wavelength absorption band around 360 nm and the much longer decay components could be attributed to the existence of charge transfer state of the dyes in solutions. DSSC device fabricated by using methoxy substituted dye (BI5a) as a sensitizer shows much better incident photon-to-current conversion efficiency (IPCE) of 64% giving cell efficiency of 2.68%. - Graphical abstract: Display Omitted - Highlights: • Long decay times suggest the delayed fluorescence caused by the existence of ICT. • The best solar energy conversion efficiency was obtained for BI5a dye (2.68%). • More fluorescent BI5a dye gives higher photocurrent generation

  13. Hypochlorous acid turn-on boron dipyrromethene probe based on oxidation of methyl phenyl sulfide

    International Nuclear Information System (INIS)

    Liu, Shi-Rong; Vedamalai, Mani; Wu, Shu-Pao

    2013-01-01

    Graphical abstract: -- Highlights: •A BODIPY-based green fluorescent probe for sensing HOCl was developed. •The probe utilizes HOCl-promoted oxidation of methyl phenyl sulfide to produce a proportional fluorescence response to the concentration of HOCl. •Confocal fluorescence microscopy imaging of RAW264.7 cells demonstrated that the HCS probe might have application in the investigation of HOCl roles in biological systems. -- Abstract: A boron dipyrromethene (BODIPY)-based fluorometric probe, HCS, has been successfully developed for the highly sensitive and selective detection of hypochlorous acid (HOCl). The probe is based on the specific HOCl-promoted oxidation of methyl phenyl sulfide. The reaction is accompanied by a 160-fold increase in the fluorescent quantum yield (from 0.003 to 0.480). The fluorescent turn-on mechanism is accomplished by suppression of photoinduced electron transfer (PET) from the methyl phenyl sulfide group to BODIPY. The fluorescence intensity of the reaction between HOCl and HCS shows a good linearity in the HOCl concentration range 1–10 μM. The detection limit is 23.7 nM (S/N = 3). In addition, confocal fluorescence microscopy imaging using RAW264.7 macrophages demonstrates that the HCS probe could be an efficient fluorescent detector for HOCl in living cells

  14. Hypochlorous acid turn-on boron dipyrromethene probe based on oxidation of methyl phenyl sulfide

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shi-Rong; Vedamalai, Mani; Wu, Shu-Pao, E-mail: spwu@mail.nctu.edu.tw

    2013-10-24

    Graphical abstract: -- Highlights: •A BODIPY-based green fluorescent probe for sensing HOCl was developed. •The probe utilizes HOCl-promoted oxidation of methyl phenyl sulfide to produce a proportional fluorescence response to the concentration of HOCl. •Confocal fluorescence microscopy imaging of RAW264.7 cells demonstrated that the HCS probe might have application in the investigation of HOCl roles in biological systems. -- Abstract: A boron dipyrromethene (BODIPY)-based fluorometric probe, HCS, has been successfully developed for the highly sensitive and selective detection of hypochlorous acid (HOCl). The probe is based on the specific HOCl-promoted oxidation of methyl phenyl sulfide. The reaction is accompanied by a 160-fold increase in the fluorescent quantum yield (from 0.003 to 0.480). The fluorescent turn-on mechanism is accomplished by suppression of photoinduced electron transfer (PET) from the methyl phenyl sulfide group to BODIPY. The fluorescence intensity of the reaction between HOCl and HCS shows a good linearity in the HOCl concentration range 1–10 μM. The detection limit is 23.7 nM (S/N = 3). In addition, confocal fluorescence microscopy imaging using RAW264.7 macrophages demonstrates that the HCS probe could be an efficient fluorescent detector for HOCl in living cells.

  15. 2-[(3,5-Dimethyl-1-phenyl-1H-pyrazol-4-ylmethylene]indane-1,3-dione

    Directory of Open Access Journals (Sweden)

    Abdullah M. Asiri

    2011-02-01

    Full Text Available The title compound 2-[(3,5-dimethyl-1-phenyl-1H-pyrazol-4-ylmethylene]-indane-1,3-dione (3 was synthesized in high yield by reaction of 3,5-dimethyl-1-phenyl-pyrazole-4-carbaldehyde and indane-1,3-dione in ethanol in the presence of pyridine. The structure of this new compound was confirmed by elemental analysis, IR, 1H NMR, 13C NMR and GC-MS spectral analysis.

  16. Synthesis and characterization of tris[butyl-(1-methyl-3-phenyl-propyl-dithiocarbamato]-cobalt(III seskvitoluene

    Directory of Open Access Journals (Sweden)

    TIBOR SABO

    2002-02-01

    Full Text Available A new bidentate ligand butyl-(1-methyl-3-phenyl-propyl-dithiocarbamate (bmFpdtc was prepared, as the sodium salt. In the reaction of hexaaminecobalt(III chloride with NabmFpdtc, the corresponding tris[butyl-(1-methyl-3-phenyl-propyl-dithiocarbamato]cobalt(III, [Co(bmFpdtc3] complex was prepared. The complex was characterized by elemental analysis, infrared, electronic absorption, 1H and 13C-NMR spectroscopy.

  17. Synthesis and characterization of tris[butyl-(1-methyl-3-phenyl-propyl)-dithiocarbamato]-cobalt(III) seskvitoluene

    OpenAIRE

    TIBOR SABO; ISMET M. HODZIC; SRECKO R. TRIFUNOVIC; VESNA M. DJINOVIC; GORAN N. KALUDJEROVIC

    2002-01-01

    A new bidentate ligand butyl-(1-methyl-3-phenyl-propyl)-dithiocarbamate (bmFpdtc) was prepared, as the sodium salt. In the reaction of hexaaminecobalt(III) chloride with NabmFpdtc, the corresponding tris[butyl-(1-methyl-3-phenyl-propyl)-dithiocarbamato]cobalt(III), [Co(bmFpdtc)3] complex was prepared. The complex was characterized by elemental analysis, infrared, electronic absorption, 1H and 13C-NMR spectroscopy.

  18. Diode laser slit-jet spectra and analysis of the ν14 fundamental of 1-chloro-1,1-difluoroethane (HCFC-142b)

    Science.gov (United States)

    D'Amico, Giuseppe; Snels, Marcel

    2003-01-01

    High resolution infrared spectra (0.001 cm -1 FWHM) have been measured for mixtures of 1-chloro-1,1-difluoroethane in Ne, expanded in a supersonic planar jet. The ν14 fundamental has been analyzed for both isotopic species, CH3CF235Cl and CH3CF237Cl.

  19. Bioactivation mechanism of the cytotoxic and nephrotoxic S-conjugate S-(2-chloro-1,1,2-trifluoroethyl)-L-cysteine

    International Nuclear Information System (INIS)

    Dekant, W.; Lash, L.H.; Anders, M.W.

    1987-01-01

    The bioactivation of S-(2-chloro-1,1,2-trifluoroethyl)-L-cysteine (CTFC) was studied with purified bovine kidney cysteine conjugate β-lyase and with N-dodecylpyridoxal bromide in cetyltrimethylammonium bromide micelles as a pyridoxal model system. The β-lyase and the pyridoxal model system converted CTFC to chlorofluoroacetic acid and inorganic fluoride, which were identified by 19 F NMR spectrometry. 2-Chloro-1,1,2-trifluoroethanethiol and chlorofluorothionoacetyl fluoride were formed as metabolites of CTFC and were trapped with benzyl bromide and diethylamine, respectively, to yield benzyl 2-chloro-1,1,2-trifluoroethyl sulfide and N,N-diethyl chlorofluorothioacetamide, which were identified by gas chromatography/mass spectrometry. The bioactivation mechanism of CTFC therefore involves the initial formation of the unstable thiol 2-chloro-1,1,2-trifluoroethanethiol, which loses hydrogen fluoride to form the acylating agent chlorofluorothionoacetyl fluoride; hydrolysis of the thionoacyl fluoride affords the stable, terminal metabolites chlorofluoroacetic acid and inorganic fluoride. The intermediate acylating agent and chlorofluoroacetic acid may contribute to the cytotoxic effects of CTFC

  20. {4-Phenyl-1-[1-(1,3-thiazol-2-ylethylidene]thiosemicarbazidato}{4-phenyl-1-[1-(1,3-thiazol-2-ylethylidene]thiosemicarbazide}nickel(II chloride monohydrate

    Directory of Open Access Journals (Sweden)

    Ramaiyer Venkatraman

    2010-05-01

    Full Text Available In the title compound, [Ni(C12H11N4S2(C12H12N4S2]Cl·H2O, the NiII ion is chelated by two 2-acetylthiazole-3-phenylthiosemicarbazone ligands, forming a distorted octahedral complex. The metal ion is coordinated via the thiazole nitrogen, imine nitrogen and thione sulfur atoms from each thiosemicarbazone ligand, and two coordinating units lie almost perpendicular to each other give dihedral angle = 81.89 (1°]. One thiosemicarbazone unit is found to bind a chloride anion through two hydrogen bonds, while the other is linked with the disordered crystal water molecule. Two molecules are connected to each other through an intermolecular N—H...S interaction, forming a centrosymmetric dimer. Dimers are linked into sheets by π–π stacking of two phenyl rings [shortest C...C distance = 4.041 (3 Å].

  1. Extending the synthetic utilities of the tandem cyclic sulfate rearrangement-opening process: Synthesis of β-hydroxy-y-phenyl-γ-phenyl-γ-lactam

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Nagum; Yu, Min Lee; Jun, Hye Yeon; Ko, Soo Y. [Dept. of Chemistry, Ewha Womans University, Seoul (Korea, Republic of)

    2016-12-15

    Cinnamyl alcohol is an obvious choice of starting material that provides the carbon framework for the syntheses of these compounds. Stereoselective oxidations (epoxidation or dihydroxylation) pave the way for the introductions of O-/N-substituents. Issues of regioselections need to be dealt with in these transformation, which may be tackled either in the activation steps, in the substitution steps, or in the protection steps. In conclusion, we have incorporated a nitrile function at C-3 of the phenylpropyl skeleton in our tandem cyclic sulfate rearrangement-epoxide opening and epoxide ring closure-epoxide opening processes. The one-carbon extension broadens the synthetic utilities of our tandem processes, as exemplified in our synthesis of β-hydroxy-γ-phenyl-γ-lactam.

  2. Preparation of (+)- and (-)- β-phenyl- and β-(4-chlorophenyl)-γ- butyro lactones: Key intermediates in the synthesis of β-phenyl-Gaba and baclofene

    Energy Technology Data Exchange (ETDEWEB)

    Gomez G, J.; Melendez R, M.; Suarez C, O. R.; Castelan D, L. E.; Fragoso V, M. J.; Lopez V, E.; Sanchez Z, M., E-mail: melendez@uaeh.edu.mx [Universidad Autonoma del Estado de Hidalgo, Area Academica de Quimica, Carretera Pachuca-Tulancingo Km. 4.5, Mineral de la Reforma 42184, Hidalgo (Mexico)

    2014-07-01

    the preparation of β-phenyl- and β-(4-chlorophenyl)-γ-butyro lactones (±)-4 and their resolution to the corresponding (+)-(S)-3, (-)-(R)-3 and (+)-(S)-4, (-)-(R)-4 through formation, flash column chromatography separation and subsequent hydrolysis of dia stereoisomeric 4-hydroxybutyramide s (2'R,3S)-5, (2'R,3R)-5, (2'R,3S)-6 and (2'R,3R)-6 is described. The absolute configuration assignment of enantiopure 3 and 4 was supported by X-ray crystallographic structures of (2'R,3R)-5, (2'R,3S)-6 and (2'R,3R)-6. (Author)

  3. Preparation of (+)- and (-)- β-phenyl- and β-(4-chlorophenyl)-γ- butyro lactones: Key intermediates in the synthesis of β-phenyl-Gaba and baclofene

    International Nuclear Information System (INIS)

    Gomez G, J.; Melendez R, M.; Suarez C, O. R.; Castelan D, L. E.; Fragoso V, M. J.; Lopez V, E.; Sanchez Z, M.

    2014-01-01

    the preparation of β-phenyl- and β-(4-chlorophenyl)-γ-butyro lactones (±)-4 and their resolution to the corresponding (+)-(S)-3, (-)-(R)-3 and (+)-(S)-4, (-)-(R)-4 through formation, flash column chromatography separation and subsequent hydrolysis of dia stereoisomeric 4-hydroxybutyramide s (2'R,3S)-5, (2'R,3R)-5, (2'R,3S)-6 and (2'R,3R)-6 is described. The absolute configuration assignment of enantiopure 3 and 4 was supported by X-ray crystallographic structures of (2'R,3R)-5, (2'R,3S)-6 and (2'R,3R)-6. (Author)

  4. Covalent modification of mutant rat P2X2 receptors with a thiol-reactive fluorophore allows channel activation by zinc or acidic pH without ATP.

    Directory of Open Access Journals (Sweden)

    Shlomo S Dellal

    Full Text Available Rat P2X2 receptors open at an undetectably low rate in the absence of ATP. Furthermore, two allosteric modulators, zinc and acidic pH, cannot by themselves open these channels. We describe here the properties of a mutant receptor, K69C, before and after treatment with the thiol-reactive fluorophore Alexa Fluor 546 C(5-maleimide (AM546. Xenopus oocytes expressing unmodified K69C were not activated under basal conditions nor by 1,000 µM ATP. AM546 treatment caused a small increase in the inward holding current which persisted on washout and control experiments demonstrated this current was due to ATP independent opening of the channels. Following AM546 treatment, zinc (100 µM or acidic external solution (pH 6.5 elicited inward currents when applied without any exogenous ATP. In the double mutant K69C/H319K, zinc elicited much larger inward currents, while acidic pH generated outward currents. Suramin, which is an antagonist of wild type receptors, behaved as an agonist at AM546-treated K69C receptors. Several other cysteine-reactive fluorophores tested on K69C did not cause these changes. These modified receptors show promise as a tool for studying the mechanisms of P2X receptor activation.

  5. Magnetic field effects on exciplex-forming systems: the effect on the locally excited fluorophore and its dependence on free energy.

    Science.gov (United States)

    Kattnig, Daniel R; Rosspeintner, Arnulf; Grampp, Günter

    2011-02-28

    This study addresses magnetic field effects in exciplex forming donor-acceptor systems. For moderately exergonic systems, the exciplex and the locally excited fluorophore emission are found to be magneto-sensitive. A previously introduced model attributing this finding to excited state reversibility is confirmed. Systems characterised by a free energy of charge separation up to approximately -0.35 eV are found to exhibit a magnetic field effect on the fluorophore. A simple three-state model of the exciplex is introduced, which uses the reaction distance and the asymmetric electron transfer reaction coordinate as pertinent variables. Comparing the experimental emission band shapes with those predicted by the model, a semi-quantitative picture of the formation of the magnetic field effect is developed based on energy hypersurfaces. The model can also be applied to estimate the indirect contribution of the exchange interaction, even if the perturbative approach fails. The energetic parameters that are essential for the formation of large magnetic field effects on the exciplex are discussed.

  6. Allergenicity evaluation of p-chloro-m-cresol and p-chloro-m-xylenol by non-radioactive murine local lymph-node assay and multiple-dose guinea pig maximization test

    International Nuclear Information System (INIS)

    Yamano, Tetsuo; Shimizu, Mitsuru; Noda, Tsutomu

    2003-01-01

    p-Chloro-m-cresol (PCMC) and p-chloro-m-xylenol (PCMX) are known to cause allergic contact dermatitis. For risk assessment of skin sensitizers, information on dose-response profiles in the induction and elicitation phases and cross-reactivity with analogous chemicals are important. In the non-radioactive local lymph-node assay (LLNA) using 5-bromo-2'-deoxyuridine instead of 3 H-methyl thymidine, significant effect on lymph node cell proliferation was detected at 10% PCMC and 25% PCMX, while in the multiple-dose guinea pig maximization test (GPMT) at least one animal tested in the group was sensitized at a 5 ppm induction dose of either chemical. When mean skin reaction score in an animal group maximally sensitized with each allergen with the GPMT was plotted against log challenge concentration, linear regression lines with high correlations were obtained in both cases. The calculated elicitation threshold was lower for PCMC than PCMX. The area under the linear regression line between the threshold point and 1% of the elicitation concentration, another index of relative elicitation potency, was also greater for PCMC. Bidirectional cross-reactivity between PCMX and PCMC was detected in the GPMT. PCMC was thus identified in both LLNA and GPMT as a stronger sensitizer than PCMX in both the induction and elicitation phases. These results suggest that the non-radioactive LLNA is a simple and useful method for evaluating allergenicity in the induction phase, while the GPMT using a maximally sensitized animal group is more suitable for assessing the dose-response profile and cross-reactivity in the elicitation phase

  7. Electrochemical oxidation of 4-chloro phenol over a carbon paste electrode modified with Zn Al layered double hydroxides

    International Nuclear Information System (INIS)

    Hernandez F, D.; Palomar P, M.; Licona S, T. de J.; Romero R, M.; Valente, Jaime S.

    2014-01-01

    A study is presented on the electrochemical oxidation of 4-chloro phenol (4cp) in aqueous solution using a bare carbon paste electrode, Cpe, and another one that was modified with Zn Al layered double hydroxides (Cpe/Zn Al-LDH). The electro-oxidation was effected at ph values ranging from 3 up to 11. It was found through cyclic voltammetry that this process was irreversible, namely, there were no reduction peaks, and that depending on the nature of the electrode, the anodic current was limited either by adsorption (Cpe) or diffusion (Cpe/Zn Al-LDH). The energy required and the oxidation reaction rate depended on the ph and on the nature of the electrode, such that the greater rates were obtained when the Cpe/Zn Al-LDH electrode and acid ph were used. The Zn Al-LDH was characterized by means of X-ray diffraction. (Author)

  8. p-chloro- and p-bromo-benzoylacetoneoxime as the spectrophotometric reagents for palladium and ruthenium(III)

    International Nuclear Information System (INIS)

    Yeole, V.V.; Langade, A.D.; Shinde, V.M.

    1980-01-01

    A procedure is described for the extractive spectrophotometric determination of palladium or ruthenium(III) using p-chloro or p-bromobenzoylacetoneoxime as the reagent. The yellow palladium complexes which are extracted into chloroform from an aqueous solution of pH 3.5, absorb as 400 nm and conform to Beer's law in the range of 10 to 100 μg of Pd/10 ml of organic phase. The orange-red ruthenium complexes which are extracted into ethylacetate from an aqueous solution of pH 5.0, absorbs at 475 nm and conforms to Beer's law in the range of 20 to 200 μg of Ru/10 ml of organic phase. The molar absorptivities, Sandell's sensitivities and instability constants are reported. (author)

  9. Occurrence of 3-chloro-propane-1,2-diol (3-MCPD) and related compounds in foods: a review.

    Science.gov (United States)

    Hamlet, C G; Sadd, P A; Crews, C; Velísek, J; Baxter, D E

    2002-07-01

    A critical review of the occurrence of 3-chloro-propane-1,2-diol (3-MCPD) in foods not known to contain hydrolysed vegetable proteins is presented. The review covers the properties and chemistry of 3-MCPD and the current methods of analysis in foodstuffs. The results of UK surveys of 3-MCPD occurrence in both retail foods and commercial food ingredients are discussed with particular reference to cereal, meat and dairy products. The possible mechanisms for the formation and decay of 3-MCPD in foods are suggested. The review does not cover the detailed toxicology of 3-MCPD and its occurrence in hydrolysed vegetable proteins, which have been considered elsewhere, nor possible issues such as in-vivo formation.

  10. A localized surface plasmon resonance (LSPR) immunosensor for CRP detection using 4-chloro-1-naphtol (4-CN) precipitation

    Science.gov (United States)

    Ha, Su-Ji; Park, Jin-Ho; Byun, Ju-Young; Ahn, Young-Deok; Kim, Min-Gon

    2017-07-01

    In this study, C-reactive protein (CRP) was detected by monitoring of LSPR shift promoted by precipitation of 4-chloro-1-naphthol (4-CN). The precipitation occurred by horseradish peroxide (HRP) catalyst which is modified at CRP-detection antibody utilized in sandwich enzyme-linked immunosorbent assay (ELISA) on gold nano bipyramid (GNBP) substrate. Due to 4-CN precipitates which are located nearby the surface of GNBP, local refractive index (RI) and molecular density were greatly increased. This phenomenon eventually induced strong spectral red-shift of absorption band of GNBP. An excellent linear relationship (R2=0.9895) between the LSPR shift and CRP concentration was obtained in the range from 100 pg/mL to 100 ng/mL and limit of detection (LOD) was reached to 87 pg/mL.

  11. A new look into the quantum chemical and spectroscopic investigations of 5-chloro-1-methyl-4-nitroimidazole.

    Science.gov (United States)

    Arjunan, V; Raj, Arushma; Anitha, R; Mohan, S

    2014-05-05

    Optimised geometrical structural parameters, harmonic vibrational frequencies, natural bonding orbital analysis and frontier molecular orbitals are determined by B3LYP and B3PW91 methods. The exact geometry of 5-chloro-1-methyl-4-nitroimidazole is determined through conformational analysis. The experimentally observed infrared and Raman bands have been assigned and analysed. The (13)C and (1)H NMR chemical shifts of the compound are investigated. The total electron density and molecular electrostatic potentials are determined. The electrostatic potential (electron+nuclei) distribution, molecular shape, size and dipole moments of the molecule have been displayed. The energies of the frontier molecular orbitals and LUMO-HOMO energy gap are measured. The possible electronic transitions of the molecule are studied by TD-DFT method along with the UV-Visible spectrum. The structure-activity relationship of the compound is also investigated by conceptual DFT methods. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Electrochemical oxidation of 4-chloro phenol over a carbon paste electrode modified with Zn Al layered double hydroxides

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez F, D.; Palomar P, M.; Licona S, T. de J.; Romero R, M. [Universidad Autonoma Metropolitana, Unidad Azcapotzalco, Departamento de Materiales, Av. San Pablo 180, Col. Reynosa-Tamaulipas, 02200 Mexico D. F. (Mexico); Valente, Jaime S., E-mail: mepp@correo.azc.uam.mx [Instituto Mexicano del Petroleo, Eje Central No. 152, 07730 Mexico D. F. (Mexico)

    2014-07-01

    A study is presented on the electrochemical oxidation of 4-chloro phenol (4cp) in aqueous solution using a bare carbon paste electrode, Cpe, and another one that was modified with Zn Al layered double hydroxides (Cpe/Zn Al-LDH). The electro-oxidation was effected at ph values ranging from 3 up to 11. It was found through cyclic voltammetry that this process was irreversible, namely, there were no reduction peaks, and that depending on the nature of the electrode, the anodic current was limited either by adsorption (Cpe) or diffusion (Cpe/Zn Al-LDH). The energy required and the oxidation reaction rate depended on the ph and on the nature of the electrode, such that the greater rates were obtained when the Cpe/Zn Al-LDH electrode and acid ph were used. The Zn Al-LDH was characterized by means of X-ray diffraction. (Author)

  13. Solar photoelectro-Fenton degradation of the herbicide 4-chloro-2-methylphenoxyacetic acid optimized by response surface methodology

    International Nuclear Information System (INIS)

    Garcia-Segura, Sergi; Almeida, Lucio Cesar; Bocchi, Nerilso; Brillas, Enric

    2011-01-01

    Highlights: → The herbicide MCPA is quickly mineralized by solar photoelectro-Fenton. → A CCRD allowed the optimization of current, Fe 2+ content and solution pH. → TOC, MCE and energy consumption are described by response surface methodology. → Generated hydroxyl radical destroys MCPA and its aromatic oxidation by-products. → UV light of solar irradiation photolyzes the Fe(III)-carboxylate complexes produced. - Abstract: A central composite rotatable design and response surface methodology (RSM) were used to optimize the experimental variables of the solar photoelectro-Fenton (SPEF) treatment of the herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA). The experiments were made with a flow plant containing a Pt/air-diffusion reactor coupled to a solar compound parabolic collector (CPC) under recirculation of 10 L of 186 mg L -1 MCPA solutions in 0.05 M Na 2 SO 4 at a liquid flow rate of 180 L h -1 with an average UV irradiation intensity of about 32 W m -2 . The optimum variables found for the SPEF process were 5.0 A, 1.0 mM Fe 2+ and pH 3.0 after 120 min of electrolysis. Under these conditions, 75% of mineralization with 71% of current efficiency and 87.7 kWh kg -1 TOC of energy consumption were obtained. MCPA decayed under the attack of generated hydroxyl radicals following a pseudo-first-order kinetics. Hydroxyl radicals also destroyed 4-chloro-2-methylphenol, methylhydroquinone and methyl-p-benzoquinone detected as aromatic by-products. Glycolic, maleic, fumaric, malic, succinic, tartronic, oxalic and formic acids were identified as generated carboxylic acids, which form Fe(III) complexes that are quickly photodecarboxylated by the UV irradiation of sunlight at the CPC photoreactor. A reaction sequence for the SPEF degradation of MCPA was proposed.

  14. Antifungal Effect of Novel 2-bromo-2-chloro-2-(4-chlorophenylsulfonyl-1-phenylethanone against Candida strains

    Directory of Open Access Journals (Sweden)

    Monika Staniszewska

    2016-08-01

    Full Text Available We investigated the antifungal activity of novel a 2-bromo-2-chloro-2-(4-chlorophenylsulfonyl-1-phenylethanone (compound 4. The synthesis of compound 4 was commenced from sodium 4-chlorobenzene sulfinate and the final product was obtained by treatment of β-chloro β-keto-sulfone with sodium hypobromite. The sensitivity of sixty three clinical isolates belonging to the most relevant Candida species towards compound 4 using the method M27-A3 was evaluated. We observed among most of the clinical strains of C. albicans MIC ranging from 0.00195 to 0.0078 µg/mL. Compound 4 at 32 μg/mL exhibited fungicidal activity against nine Candida strains tested using the MFC assay. Compound 4 displayed anti-Candida activity (with clear endpoint against 22% of clinical strains of Candida. Under compound 4, Candida susceptibility and tolerance, namely paradoxical effect (PG, was found for only two clinical isolates (C. glabrata and C. parapsilosis and reference strain 14053 using both M27-A3 and MFC method. We found that compound 4 does not induce toxicity in vivo against larvae of Galleria mellonella (≥97% survival and it displays reduced toxicity on mammalian cells in vitro (

  15. Conducting polymers of decanedioic acid bis-(4-pyrrol-1-yl-phenyl) ester

    International Nuclear Information System (INIS)

    Cirpan, A.; Guner, Y.; Toppare, L.

    2004-01-01

    A dipyrrolyl monomer was synthesized via the reaction between 4-pyrrol-1-yl phenol and decanedioyl dichloride. The electrochemical behavior of this monomer was studied. Polymerization of decanedioic acid bis-(4-pyrrol-1-yl-phenyl) ester (DAPE) was achieved by chemical and constant current electrolyses methods. Copolymerization of DAPE with thiophene was performed by constant potential electrolysis in acetonitrile-tetrabutylammonium tetrafluoroborate (TBAFB), dichloromethane-TBAFB, solvent-electrolyte couples. The chemical structures and properties were investigated by Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, differential scanning calorimetry and thermal gravimetry analysis. The conductivities of the samples were measured by a four-probe technique

  16. Conducting polymers of decanedioic acid bis-(4-pyrrol-1-yl-phenyl) ester

    Energy Technology Data Exchange (ETDEWEB)

    Cirpan, A.; Guner, Y.; Toppare, L

    2004-05-15

    A dipyrrolyl monomer was synthesized via the reaction between 4-pyrrol-1-yl phenol and decanedioyl dichloride. The electrochemical behavior of this monomer was studied. Polymerization of decanedioic acid bis-(4-pyrrol-1-yl-phenyl) ester (DAPE) was achieved by chemical and constant current electrolyses methods. Copolymerization of DAPE with thiophene was performed by constant potential electrolysis in acetonitrile-tetrabutylammonium tetrafluoroborate (TBAFB), dichloromethane-TBAFB, solvent-electrolyte couples. The chemical structures and properties were investigated by Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, differential scanning calorimetry and thermal gravimetry analysis. The conductivities of the samples were measured by a four-probe technique.

  17. Phenyl ethers from cultured lichen mycobionts of Graphis scripta var. serpentina and G. rikuzensis.

    Science.gov (United States)

    Takenaka, Yukiko; Tanahashi, Takao; Nagakura, Naotaka; Hamada, Nobuo

    2003-07-01

    Spore-derived mycobionts of the lichen Graphis scripta var. serpentina and G. rikuzensis were cultivated on a malt-yeast extract medium supplemented with 10% sucrose and their metabolites were investigated. 3,3'-Dihydroxy-5,5'-dimethyldiphenyl ether was isolated from the cultures of the mycobionts of G. scripta var. serpentina, while a new phenyl ether, rikuzenol, along with two known diphenyl ethers, violaceol-I and violaceol-II, were isolated from those of G. rikuzensis. The structure of the new compound was determined by spectroscopic methods. Violaceol-I was chemically synthesized and interconversion between violaceol-I and violaceol-II was proven.

  18. (O-Methyl di-thio-carbonato-κS)tri-phenyl-tin(IV).

    Science.gov (United States)

    Javed, Fatima; Ali, Saqib; Shah, Wajid; Tahir, M Nawaz; Ullah, Hameed

    2013-06-01

    In the title compound, [Sn(C6H5)3(C2H3OS2)], the Sn(IV) atom adopts a distorted SnC3S tetra-hedral coordination geometry. A short Sn⋯O contact [2.988 (4) Å] is also present. The phenyl rings are each disordered over two sets of sites with an occupancy ratio of 0.550 (8):0.450 (8). The crystal studied was found to be a racemic twin with a twin component ratio of 0.57 (18):0.43 (18).

  19. Diazido{(S-1-phenyl-N,N-bis[(2-pyridylmethyl]ethanamine}copper(II

    Directory of Open Access Journals (Sweden)

    Sankara Rao Rowthu

    2011-07-01

    Full Text Available In the title compound, [Cu(N32(C20H21N3], the CuII ion is coordinated by the three N atoms of the (S-1-phenyl-N,N-bis[(2-pyridylmethyl]ethanamine ligand and two N atoms from two azide anions, resulting in a distorted square-pyramidal environment. A weak intermolecular C—H...N hydrogen-bonding interaction between one pyridine group of the ligand and an azide N atom of an adjacent complex unit gives a one-dimensional chain structure parallel to the c axis.

  20. A New Phenyl Ethyl Glycoside from the Twigs of Acer tegmentosum.

    Science.gov (United States)

    Park, Seonju; Lee, Hwa Young; Nhiem, Nguyen Xuan; Lee, Taek Hwan; Kim, Nanyoung; Cho, Seung Hun; Kim, Seung Hyun

    2015-07-01

    One new phenyl ethyl glycoside, 2-(4-hydroxyphenyl)ethyl-O-α-L-arabinofuranosyl-(1 --> 6)-O-β-D-glucopyranoide (1) and 11 known compounds (2-12) were isolated from the twigs of Acer tegmentosum. Compound 6 showed potent anti-neuroinflammatory activity against the LPS-stimulated BV-2 microglial cells with tNO production of 25.0 ± 2.5 μM and TNF-α concentration of 617.6 ± 47.1 pg/mL at 30 μM.

  1. Synthesis and biological evaluation of trans-3-phenyl-1-indanamines as potential norepinephrine transporter imaging agents

    International Nuclear Information System (INIS)

    McConathy, Jonathan; Owens, Michael J.; Kilts, Clinton D.; Malveaux, Eugene J.; Votaw, John R.; Nemeroff, Charles B.; Goodman, Mark M.

    2005-01-01

    The development of radioligands suitable for studying the central nervous system (CNS) norepinephrine transporter (NET) in vivo will provide important new tools for examining the pathophysiology and pharmacotherapy of a variety of neuropsychiatric disorders including major depression. Towards this end, a series of trans-3-phenyl-1-indanamine derivatives were prepared and evaluated in vitro. The biological properties of the most promising compound, [ 11 C]3-BrPA, were investigated in rat biodistribution and nonhuman primate PET studies. Despite high in vitro affinity for the human NET, the uptake of [ 11 C]3-BrPA in the brain and the heart was not displaceable with pharmacological doses of NET antagonists

  2. Crystal structure of a diaryl carbonate: 1,3-phenylene bis(phenyl carbonate

    Directory of Open Access Journals (Sweden)

    Marina A. Solomos

    2017-12-01

    Full Text Available The whole molecule of the title compound, C20H14O6, is generated by mirror symmetry, the mirror bisecting the central benzene ring. The carbonate groups adopt an s-cis-s-cis conformation, with torsion angles of 58.7 (2 and 116.32 (15°. The crystal structure of 1,3-phenylene bis(phenyl carbonate contains no strong hydrogen bonds, though weak C—H...O and offset π–π interactions are observed, forming layers parallel to the ac plane.

  3. Derivatives of phenyl tribromomethyl sulfone as novel compounds with potential pesticidal activity

    Directory of Open Access Journals (Sweden)

    Krzysztof M. Borys

    2012-02-01

    Full Text Available A halogenmethylsulfonyl moiety is incorporated in numerous active herbicides and fungicides. The synthesis of tribromomethyl phenyl sulfone derivatives as novel potential pesticides is reported. The title sulfone was obtained by following three different synthetic routes, starting from 4-chlorothiophenol or 4-halogenphenyl methyl sulfone. Products of its subsequent nitration were subjected to the SNAr reactions with ammonia, amines, hydrazines and phenolates to give 2-nitroaniline, 2-nitrophenylhydrazine and diphenyl ether derivatives. Reduction of the nitro group of 4-tribromomethylsulfonyl-2-nitroaniline yielded the corresponding o-phenylenediamine substrate for preparation of structurally varied benzimidazoles.

  4. A theoretical study of the relaxation of a phenyl group chemisorbed to an RDX freestanding thin film

    Energy Technology Data Exchange (ETDEWEB)

    Pereverzev, Andrey, E-mail: pereverzeva@missouri.edu; Sewell, Thomas D., E-mail: sewellt@missouri.edu [Department of Chemistry, University of Missouri-Columbia, Columbia, Missouri 65211-7600 (United States)

    2016-08-07

    Energy relaxation from an excited phenyl group chemisorbed to the surface of a crystalline thin film of α-1,3,5-trinitro-1,3,5-triazacyclohexane (α-RDX) at 298 K and 1 atm is simulated using molecular dynamics. Two schemes are used to excite the phenyl group. In the first scheme, the excitation energy is added instantaneously as kinetic energy by rescaling momenta of the 11 atoms in the phenyl group. In the second scheme, the phenyl group is equilibrated at a higher temperature in the presence of static RDX geometries representative of the 298 K thin film. An analytical model based on ballistic phonon transport that requires only the harmonic part of the total Hamiltonian and includes no adjustable parameters is shown to predict, essentially quantitatively, the short-time dynamics of the kinetic energy relaxation (∼200 fs). The dynamics of the phenyl group for times longer than about 6 ps follows exponential decay and agrees qualitatively with the dynamics described by a master equation. Long-time heat propagation within the bulk of the crystal film is consistent with the heat equation.

  5. 1-(6-Chloro-2-methyl-4-phenylquinolin-3-yl-3-(3-methoxyphenylprop-2-en-1-one

    Directory of Open Access Journals (Sweden)

    Wan-Sin Loh

    2010-01-01

    Full Text Available In the title compound, C26H20ClNO2, the quinoline ring system is approximately planar with a maximum deviation of 0.028 (2 Å and forms a dihedral angle of 73.84 (5° with the phenyl ring. Two neighbouring molecules are arranged into a centrosymmetric dimer through a pair of intermolecular C—H...Cl interactions. A pair of intermolecular C—H...O hydrogen bonds link two methoxyphenyl groups into another centrosymmetric dimer, generating an R22(8 ring motif. The structure is further stabilized by C—H...π interactions.

  6. Photoluminescence and electroluminescence of a novel green-yellow emitting material-5,6-Bis-[4-(naphthalene-1-yl-phenyl-amino)-phenyl] -pyrazine-2,3-dicarbonitrile

    International Nuclear Information System (INIS)

    Chew Siewling; Wang Pengfei; Hong Zirou; Kwong, H.L.; Tang Jianxin; Sun Shiling; Lee, C.S.; Lee, S.-T.

    2007-01-01

    A new compound with intramolecular charge transfer (ICT) property-5,6-Bis-[4-(naphthalene-1-yl-phenyl-amino)-phenyl] -pyrazine-2,3-dicarbonitrile(BNPPDC) was synthesized. The new compound was strongly fluorescent in non-polar and moderately polar solvents, as well as in thin solid film. The absorption and emission maxima shifted to longer wavelength with increasing solvent polarity. The fluorescence quantum yield also increased with increasing solvent polarity from non-polar to moderately polar solvents, then decreased with further increase of solvent polarity. This indicates both 'positive' and 'negative' solvatokinetic effects co-existed. Using this material as hole-transporting emitter and host emitter, we fabricated two electroluminescent (EL) devices with structures of A (ITO/BNPPDC (45 nm)/1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBI) (45 nm)/Mg:Ag (200 nm) and B (ITO/N,N'-diphenyl-N,N'-bis-(3-methylphenyl) (1,1'-diphenyl)4,4'-diamine (TPD) (50 nm)/BNPPDC (20 nm)/1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBI) (45 nm)/Mg:Ag (200 nm). The devices showed green-yellow EL emission with good efficiency and high brightness. For example, the device A exhibited a high brightness of 17400 cd/m 2 at a driving voltage of 11 V and a very low turn-on voltage (2.9 V), as well as a maximum luminous efficiency 3.61 cd/A. The device B showed a similar performance with a high brightness of 12650 cd/m 2 at a driving voltage of 13 V and a maximum luminous efficiency 3.62 cd/A. In addition, the EL devices using BNPPDC as a host and 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl) -4H-pyran (DCJTB) as a dopant (configuration: ITO/TPD (60 nm)/BNPPDC:DCJTB (2%) (30 nm)/TPBI (35 nm)/Mg:Ag (200 nm)) showed a good performance with a brightness of 150 cd/m 2 at 4.5 V, a maximum brightness of 12600 cd/m 2 at 11.5 V, and a maximum luminous efficiency of 3.30 cd/A

  7. Photoluminescence and electroluminescence of a novel green-yellow emitting material-5,6-Bis-[4-(naphthalene-1-yl-phenyl-amino)-phenyl] -pyrazine-2,3-dicarbonitrile

    Energy Technology Data Exchange (ETDEWEB)

    Chew Siewling [Center of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong (China); Wang Pengfei [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100101 (China)]. E-mail: wangpf@mail.ipc.ac.cn; Hong Zirou [Center of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong (China); Kwong, H.L. [Department of Biology and Chemistry, City University of Hong Kong, Hong Kong (China); Tang Jianxin [Center of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong (China); Sun Shiling [Center of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong (China); Lee, C.S. [Center of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong (China)]. E-mail: apcslee@cityu.edu.hk; Lee, S.-T. [Center of Super-Diamond and Advanced Films (COSDAF) and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong (China)]. E-mail: apannale@cityu.edu.hk

    2007-06-15

    A new compound with intramolecular charge transfer (ICT) property-5,6-Bis-[4-(naphthalene-1-yl-phenyl-amino)-phenyl] -pyrazine-2,3-dicarbonitrile(BNPPDC) was synthesized. The new compound was strongly fluorescent in non-polar and moderately polar solvents, as well as in thin solid film. The absorption and emission maxima shifted to longer wavelength with increasing solvent polarity. The fluorescence quantum yield also increased with increasing solvent polarity from non-polar to moderately polar solvents, then decreased with further increase of solvent polarity. This indicates both 'positive' and 'negative' solvatokinetic effects co-existed. Using this material as hole-transporting emitter and host emitter, we fabricated two electroluminescent (EL) devices with structures of A (ITO/BNPPDC (45 nm)/1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBI) (45 nm)/Mg:Ag (200 nm) and B (ITO/N,N'-diphenyl-N,N'-bis-(3-methylphenyl) (1,1'-diphenyl)4,4'-diamine (TPD) (50 nm)/BNPPDC (20 nm)/1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBI) (45 nm)/Mg:Ag (200 nm). The devices showed green-yellow EL emission with good efficiency and high brightness. For example, the device A exhibited a high brightness of 17400 cd/m{sup 2} at a driving voltage of 11 V and a very low turn-on voltage (2.9 V), as well as a maximum luminous efficiency 3.61 cd/A. The device B showed a similar performance with a high brightness of 12650 cd/m{sup 2} at a driving voltage of 13 V and a maximum luminous efficiency 3.62 cd/A. In addition, the EL devices using BNPPDC as a host and 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl) -4H-pyran (DCJTB) as a dopant (configuration: ITO/TPD (60 nm)/BNPPDC:DCJTB (2%) (30 nm)/TPBI (35 nm)/Mg:Ag (200 nm)) showed a good performance with a brightness of 150 cd/m{sup 2} at 4.5 V, a maximum brightness of 12600 cd/m{sup 2} at 11.5 V, and a maximum luminous efficiency of 3.30 cd/A.

  8. Design, synthesis and inhibitory activities of 8-(substituted styrol-formamido)phenyl-xanthine derivatives on monoamine oxidase B.

    Science.gov (United States)

    Hu, Suwen; Nian, Siyun; Qin, Kuiyou; Xiao, Tong; Li, Lingna; Qi, Xiaolu; Ye, Faqing; Liang, Guang; Hu, Guoxin; He, Jincai; Yu, Yinfei; Song, Bo

    2012-01-01

    The design and synthesis of two series of 8-(substituted styrol-formamido)phenyl-xanthine derivatives are described. Their in vitro monoamine oxidase B (MAO-B) inhibition were tested and the effect of substituents on the N-7, phenyl and the substituted positions are discussed. It was observed that compound 9b displayed significant MAO-B inhibition activity and selectivity, fluorine substitution plays a key role in the selectivity of MAO-B inhibition, and the styrol-formamido group at position-3' may enhance the activity and selectivity of 8-phenyl-xanthine analogues. These results suggest that such compounds may be utilized for the development of new candidate MAO-B inhibitors for treatment of Parkinson's disease.

  9. Photochemical oxidation processes for the elimination of phenyl-urea herbicides in waters

    International Nuclear Information System (INIS)

    Benitez, F. Javier; Real, Francisco J.; Acero, Juan L.; Garcia, Carolina

    2006-01-01

    Four phenyl-urea herbicides (linuron, chlorotoluron, diuron, and isoproturon) were individually photooxidized by monochromatic UV radiation in ultra-pure aqueous solutions. The influence of pH and temperature on the photodegradation process was established, and the first-order rate constants and quantum yields were evaluated. The sequence of photodecomposition rates was: linuron > chlorotoluron > diuron > isoproturon. The simultaneous photooxidation of mixtures of the selected herbicides in several types of waters was then performed by means of UV radiation alone, and by UV radiation combined with hydrogen peroxide. The types of waters used were: ultra-pure water, a commercial mineral water, a groundwater, and a lake water. The influence of the independent variables in these processes - the presence or absence of tert-butyl alcohol, types of herbicide and waters, and concentration of hydrogen peroxide - were established and discussed. A kinetic study was performed using a competitive kinetic model that allowed various rate constants to be evaluated for each herbicide. This kinetic model allows one to predict the elimination of these phenyl-urea herbicides in contaminated waters by the oxidation systems used (UV alone and combined UV/H 2 O 2 ). The herbicide concentrations predicted by this model agree well with the experimental results that were obtained

  10. Covalent modification of calcium hydroxyapatite surface by grafting phenyl phosphonate moieties

    International Nuclear Information System (INIS)

    Aissa, Abdallah; Debbabi, Mongi; Gruselle, Michel; Thouvenot, Rene; Gredin, Patrick; Traksmaa, Rainer; Tonsuaadu, Kaia

    2007-01-01

    The reaction between phenyl phosphonic dichloride (C 6 H 5 P(O)Cl 2 ) and synthetic calcium hydroxy- and fluorapatite has been investigated. The presence of mono- or polymeric (C 6 H 5 PO) fragment bound to hydroxyapatite was evidenced by IR, and solid-state 31 P NMR spectroscopy. X-ray powder analysis has shown that the apatitic structure remains unchanged during the reaction. In contrast, no reaction was found using fluorapatite. According to the results found for these two different apatites a mechanism was proposed for the formation of covalent P-O-P bonds as the result of a reaction between the C 6 H 5 P(O)Cl 2 organic reagent and (HPO 4 ) - and/or OH - ions of the hydroxyapatite. - Graphical abstract: Representation of the first step of the reaction between the phenyl phosphonic dichloride and the hydroxyl groups on the surface of the apatite, leading to covalent P-O-P bond with elimination of HCl

  11. Microwave Assisted Enzymatic Kinetic Resolution of (±-1-Phenyl-2-propyn-1-ol in Nonaqueous Media

    Directory of Open Access Journals (Sweden)

    Saravanan Devendran

    2014-01-01

    Full Text Available Kinetic resolution of 1-phenyl-2-propyn-1-ol, an important chiral synthon, was studied through trans-esterification with acyl acetate to investigate synergism between microwave irradiation and enzyme catalysis. Lipases from different microbial origins were employed for the kinetic resolution of (R/S-1-phenyl-2-propyn-1-ol, among which Candida antarctica lipase B, immobilized on acrylic resin (Novozym 435, was found to be the best catalyst in n-hexane as solvent. Vinyl acetate was the most effective among different acyl esters studied. The effect of various parameters was studied in a systematic manner. Definite synergism between microwave and enzyme was observed. The initial rate was improved around 1.28 times under microwave irradiation than conventional heating. Under optimum conditions, maximum conversion (48.78% and high enantiomeric excess (93.25% were obtained in 2 h. From modeling studies, it is concluded that the reaction follows the Ping-Pong bi-bi mechanism with dead end alcohol inhibition. Kinetic parameters were obtained by using nonlinear regression. This process is green, clean, and easily scalable as compared to the chemical process.

  12. Kinetic α secondary deuterium isotope effects for O-ethyl S-phenyl benzaldehyde acetal hydrolysis

    International Nuclear Information System (INIS)

    Ferraz, J.P.; Cordes, E.H.

    1979-01-01

    The rate of hydrolysis of O-ethyl S-phenyl benzaldehyde acetal at 25 0 C in 20% dioxane--80% water is independent of pH over the range pH6-12; k/sub obsd/ = 1.9 x 10 -7 s -1 . Under more acidic conditions, the rate increases linearly with the activity of the hydrated proton; k 2 = 2.95 x 10 -2 M -1 s -1 . The kinetic α secondary deuterium isotope effect for acid-catalyzed hydrolysis of O-ethyl S-phenyl benzaldehyde acetal, measured at 25 0 C in 20% aqueous dioxane containing 0.05 M HCl, is k/sub H//k/sub D/ = 1.038 +- 0.008, a value consistent with a transition state in which the C--S bond is stretched rather little. In contrast, the corresponding isotope effect for the pH-independent hydrolysis of this substrate, measured at 42.5 0 C in 20% dioxane, is 1.13 +- 0.02, a value consistent with complete C--S bond cleavage in the transition state and rate-determining diffusion apart of the ion-pair formed as the initial intermediate, in accord with the suggestion of Jensen and Jencks. 1 figure, 4 tables

  13. Photochemical oxidation processes for the elimination of phenyl-urea herbicides in waters

    Energy Technology Data Exchange (ETDEWEB)

    Benitez, F. Javier [Departamento de Ingenieria Quimica y Energetica, Universidad de Extremadura, 06071 Badajoz (Spain)]. E-mail: javben@unex.es; Real, Francisco J. [Departamento de Ingenieria Quimica y Energetica, Universidad de Extremadura, 06071 Badajoz (Spain); Acero, Juan L. [Departamento de Ingenieria Quimica y Energetica, Universidad de Extremadura, 06071 Badajoz (Spain); Garcia, Carolina [Departamento de Ingenieria Quimica y Energetica, Universidad de Extremadura, 06071 Badajoz (Spain)

    2006-11-16

    Four phenyl-urea herbicides (linuron, chlorotoluron, diuron, and isoproturon) were individually photooxidized by monochromatic UV radiation in ultra-pure aqueous solutions. The influence of pH and temperature on the photodegradation process was established, and the first-order rate constants and quantum yields were evaluated. The sequence of photodecomposition rates was: linuron > chlorotoluron > diuron > isoproturon. The simultaneous photooxidation of mixtures of the selected herbicides in several types of waters was then performed by means of UV radiation alone, and by UV radiation combined with hydrogen peroxide. The types of waters used were: ultra-pure water, a commercial mineral water, a groundwater, and a lake water. The influence of the independent variables in these processes - the presence or absence of tert-butyl alcohol, types of herbicide and waters, and concentration of hydrogen peroxide - were established and discussed. A kinetic study was performed using a competitive kinetic model that allowed various rate constants to be evaluated for each herbicide. This kinetic model allows one to predict the elimination of these phenyl-urea herbicides in contaminated waters by the oxidation systems used (UV alone and combined UV/H{sub 2}O{sub 2}). The herbicide concentrations predicted by this model agree well with the experimental results that were obtained.

  14. Acquisition of a potent and selective TC-PTP inhibitor via a stepwise fluorophore-tagged combinatorial synthesis and screening strategy.

    Science.gov (United States)

    Zhang, Sheng; Chen, Lan; Luo, Yong; Gunawan, Andrea; Lawrence, David S; Zhang, Zhong-Yin

    2009-09-16

    Protein tyrosine phosphatases (PTPs) regulate a broad range of cellular processes including proliferation, differentiation, migration, apoptosis, and immune responses. Dysfunction of PTP activity is associated with cancers, metabolic syndromes, and autoimmune disorders. Consequently, small molecule PTP inhibitors should serve not only as powerful tools to delineate the physiological roles of these enzymes in vivo but also as lead compounds for therapeutic development. We describe a novel stepwise fluorophore-tagged combinatorial library synthesis and competitive fluorescence polarization screening approach that transforms a weak and general PTP inhibitor into an extremely potent and selective TC-PTP inhibitor with highly efficacious cellular activity. The result serves as a proof-of-concept in PTP inhibitor development, as it demonstrates the feasibility of acquiring potent, yet highly selective, cell permeable PTP inhibitory agents. Given the general nature of the approach, this strategy should be applicable to other PTP targets.

  15. Use of zero order diffraction of a grating monochromator towards convenient and sensitive detection of fluorescent analytes in multi fluorophoric systems

    Science.gov (United States)

    Panigrahi, Suraj Kumar; Mishra, Ashok Kumar

    2018-02-01

    White light excitation fluorescence (WLEF) is known to possess analytical advantage in terms of enhanced sensitivity and facile capture of the entire fluorescence spectral signature of multi component fluorescence systems. Using the zero order diffraction of the grating monochromator on the excitation side of a commercial spectrofluorimeter, it has been shown that WLEF spectral measurements can be conveniently carried out. Taking analyte multi-fluorophoric systems like (i) drugs and vitamins spiked in urine sample, (ii) adulteration of extra virgin olive oil with olive pomace oil and (iii) mixture of fabric dyes, it was observed that there is a significant enhancement of measurement sensitivity. The total fluorescence spectral response could be conveniently analysed using PLS2 regression. This work brings out the ease of the use of a conventional fluorimeter for WLEF measurements.

  16. Migration of methyl and phenyl radicals, oxygen and sulphur atoms in certain diphenylthiophosphorane derivatives under electron impact

    International Nuclear Information System (INIS)

    Cauquis, G.; Divisia, B.; Ulrich, J.

    The fragmentation of various diphenylthiophosphoranes (Ph 2 P(S)R) subjected to electron impact gives rise to rearrangements dependent on the nature of the radical R. Migrations of phenyl or methyl radicals from phosphorus towards sulphur were thus observed for R=Ph, CH 3 , CH 2 Ph and NH 2 . When an electrophilic centre is formed, during a fragmentation, on a carbon in the α-position of the diphenylthiophosphoranyl radical, migrations of sulphur atoms and phenyl radicals take place from the phosphorus towards the carbon. This is found to be the case with certain fragmentations of diazo 5 and 6 compounds [fr

  17. Substituted piperazines as nootropic agents: 2- or 3-phenyl derivatives structurally related to the cognition-enhancer DM235.

    Science.gov (United States)

    Guandalini, Luca; Martino, Maria Vittoria; Di Cesare Mannelli, Lorenzo; Bartolucci, Gianluca; Melani, Fabrizio; Malik, Ruchi; Dei, Silvia; Floriddia, Elisa; Manetti, Dina; Orlandi, Francesca; Teodori, Elisabetta; Ghelardini, Carla; Romanelli, Maria Novella

    2015-04-15

    A series of 2-phenyl- or 3-phenyl piperazines, structurally related to DM235 and DM232, two potent nootropic agents, have been prepared and tested in the mouse passive-avoidance test, to assess their ability to revert scopolamine-induced amnesia. Although the newly synthesized molecules were less potent than the parent compounds, some useful information has been obtained from structure-activity relationships. A small but significant enantioselectivity has been found for the most potent compound 5a. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Synthesis of optically active α-Methylstyrene-N- phenyl maleamic acid copolymer via asymmetric induction by 1-menthol

    International Nuclear Information System (INIS)

    Khettab, F. A.; Korshid, C. A.

    1998-01-01

    Copolymerization of α-methylstyrene with N-phenyl maleamic acid was studied in the presence and absence of 1-menthol, using 2,2 ' - azobis (isobutyronitrils) AIBN as initiator in toluene. The optically active copolymer is formed by the addition of 1-menthol of the copolymerization system. The observed optical activity is presumed to be due to asymmetry induced in the backbone of the copolymer by the chirality of 1-menthol. The influence of 1-menthol is considered to be caused by an electrostatic interaction between N-phenyl maleamic acid and the polar group of 1-menthol. (author). 9 refs., 1 fig., 4 tabs

  19. Crystal structure of 3-({[(morpholin-4-yl)carbono-thio-yl]sulfan-yl}acet-yl)phenyl benzoate.

    Science.gov (United States)

    Ambekar, Sachin P; Mahesh Kumar, K; Shirahatti, Arun Kumar M; Kotresh, O; Anil Kumar, G N

    2014-11-01

    In the title compound, C20H19NO4S2, the morpholine ring adopts the expected chair conformation. The central phenyl ring makes dihedral angles of 67.97 (4) and 7.74 (3)°, respectively, with the benzoate phenyl ring and the morpholine mean plane. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming zigzag chains along the b-axis direction. C-H⋯π inter-actions link centrosymmetrically related mol-ecules, reinforcing the three-dimensional structure.

  20. The periplasmic transaminase PtaA of Pseudomonas fluorescens converts the glutamic acid residue at the pyoverdine fluorophore to α-ketoglutaric acid.

    Science.gov (United States)

    Ringel, Michael T; Dräger, Gerald; Brüser, Thomas

    2017-11-10

    The periplasmic conversion of ferribactin to pyoverdine is essential for siderophore biogenesis in fluorescent pseudomonads, such as pathogenic Pseudomonas aeruginosa or plant growth-promoting Pseudomonas fluorescens The non-ribosomal peptide ferribactin undergoes cyclizations and oxidations that result in the fluorophore, and a strictly conserved fluorophore-bound glutamic acid residue is converted to a range of variants, including succinamide, succinic acid, and α-ketoglutaric acid residues. We recently discovered that the pyridoxal phosphate-containing enzyme PvdN is responsible for the generation of the succinamide, which can be hydrolyzed to succinic acid. Based on this, a distinct unknown enzyme was postulated to be responsible for the conversion of the glutamic acid to α-ketoglutaric acid. Here we report the identification and characterization of this enzyme in P. fluorescens strain A506. In silico analyses indicated a periplasmic transaminase in fluorescent pseudomonads and other proteobacteria that we termed PtaA for " p eriplasmic t ransaminase A " An in-frame-deleted ptaA mutant selectively lacked the α-ketoglutaric acid form of pyoverdine, and recombinant PtaA complemented this phenotype. The ptaA / pvdN double mutant produced exclusively the glutamic acid form of pyoverdine. PtaA is homodimeric and contains a pyridoxal phosphate cofactor. Mutation of the active-site lysine abolished PtaA activity and affected folding as well as Tat-dependent transport of the enzyme. In pseudomonads, the occurrence of ptaA correlates with the occurrence of α-ketoglutaric acid forms of pyoverdines. As this enzyme is not restricted to pyoverdine-producing bacteria, its catalysis of periplasmic transaminations is most likely a general tool for specific biosynthetic pathways. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Phenyl hepta cyclopentyl – polyhedral oligomeric silsesquioxane (ph,hcp-POSS/Polystyrene (PS nanocomposites: the influence of substituents in the phenyl group on the thermal stability

    Directory of Open Access Journals (Sweden)

    I. Blanco

    2012-12-01

    Full Text Available Some new Polystyrene (PS nanocomposites were prepared by using two Polyhedral Oligomeric Silsesquioxanes (POSSs, namely RR’7(SiO1.58 (where R = 4-methoxyphenyl or 2,4-difluorophenyl and R’ = cyclopentyl, as fillers, and their degradation was studied to investigate the effect of the electron-donor or electron-withdrawing character of the phenyl group substituents on thermal stability. Nanocomposites were synthesized by in situ polymerization of styrene in the presence of various concentrations of POSS. Proton nuclear magnetic resonance (1H NMR spectra indicated that the POSS content in the obtained nanocomposites was higher than that in reactant mixtures. Inherent viscosity (ηinh and glass transition temperature (Tg determinations indicated that the average molar mass of polymer in 4-methoxynanocomposites was the same than neat PS, while it was much lower in 2,4-difluoro derivatives. Degradations were carried out in both flowing nitrogen and static air atmospheres, in the scanning mode, at various heating rates, and temperature at 5% mass loss (T5% and the activation energy (Ea of degradation of various nanocomposites were determined. The values obtained for 4-methoxyderivatives were higher than unfilled PS thus indicating higher thermal stability. Conversely, the values found for 2,4-difluoro derivatives were lower, in some cases even than those of neat PS. The results were discussed and interpreted.

  2. [6-chloro-3-pyridylmethyl-3H]neonicotinoids as high-affinity radioligands for the nicotinic acetylcholine receptor: preparation using NaB3H4 and LiB3H4

    International Nuclear Information System (INIS)

    Latli, Bachir; Casida, J.E.

    1996-01-01

    NaB 3 H 4 and LiB 3 H 4 at 78% and 97% isotopic enrichments, respectively, were used in the synthesis of 3 H-labeled 1-(6-chloro-3-pyridyl)-methyl-2-nitromethyleneimidazolidine (CH-IMI) and N'-[(6-chloro-3-pyridyl)methyl]-n''-cyano-n'-methylacetamidine (acetamiprid) (two very potent insecticides) and of 1-(6-chloro-3-pyridyl)methyl-2-iminoimidazolidine (desnitro-IMI) (a metabolite of the commercial insecticides imidacloprid). 6-Chloronicotinoyl chloride was treated with either NaB 3 H 4 in methanol or LiB 3 H 4 in tetrahydrofuran and the resulting alcohol transformed to 2-chloro-5-chloromethylpyridine, which was then coupled to N-cyano-N'-methylacetamidine to give [ 3 H] acetamiprid (45 Ci/mmol). 2-Chloro-5-chloro[ 3 H]methylpyridine was also reacted with ethylenediamine and the product was either refluxed in absolute ethanol with 1,1-bis(methylthio)-2-nitro-ethylene to provide [ 3 H]CH-IMI or reacted in toluene with a solution of cyanogen bromide to produce [ 3 H] desnitro-IMI (each 55 Ci/mmol. (author)

  3. 40 CFR 721.5356 - Ethanol, 2,2′2″-nitrilotris-, compound with alpha-2,4,6-tris (1-phenylethyl)phenyl]-omega...

    Science.gov (United States)

    2010-07-01

    ...-, compound with alpha-2,4,6-tris (1-phenylethyl)phenyl]-omega-hydroxypoly (oxy-1,2-ethanediyl) phosphate. 721...]-omega-hydroxypoly (oxy-1,2-ethanediyl) phosphate. (a) Chemical substance and significant new uses... alpha-[2,4,6-tris(1-phenylethyl)phenyl]-omega-hydroxypoly (oxy-1,2-ethanediyl) phosphate (PMN P-98-185...

  4. Techniques in gas-phase thermolyses - Part 7. Direct surface participation in gas-phase Curie-point pyrolysis: The pyrolysis of phenyl azide

    DEFF Research Database (Denmark)

    Egsgaard, Helge; Carlsen, Lars

    1986-01-01

    The possible direct participation of the hot reactor surface in the formation of pyrolysis products was elucidated through the pyrolytic decomposition of phenyl azide. It is demonstrated that the intermediate phenyl nitrene generated reacts with elemental carbon at the filament surface, leading...

  5. Investigating Spectrum of Biological Activity of 4- and 5-Chloro-2-hydroxy-N-[2-(arylamino-1-alkyl-2-oxoethyl]benzamides

    Directory of Open Access Journals (Sweden)

    Jirina Stolarikova

    2011-03-01

    Full Text Available In this study, a series of twenty-two 5-chloro-2-hydroxy-N-[2-(arylamino-1-alkyl-2-oxoethyl]benzamides and ten 4-chloro-2-hydroxy-N-[2-(arylamino-1-alkyl-2-oxoethyl]benzamides is described. The compounds were analyzed using RP-HPLC to determine lipophilicity. Primary in vitro screening of the synthesized compounds was performed against mycobacterial, bacterial and fungal strains. They were also evaluated for their activity related to the inhibition of photosynthetic electron transport (PET in spinach (Spinacia oleracea L. chloroplasts. The compounds showed biological activity comparable with or higher than the standards isoniazid, fluconazole, penicillin G or ciprofloxacin. For all the compounds, the relationships between the lipophilicity and the chemical structure of the studied compounds as well as their structure-activity relationships are discussed.

  6. The synthesis of 7-chloro-5-pentadeuteriophenyl-1-methyl-1H-1, 5-benzodiazepine-2,4(3H, 5H)dione ([2H5]clobazam)

    International Nuclear Information System (INIS)

    Borel, A.G.; Abbott, F.S.

    1990-01-01

    Pentadeuteriophenyl clobazam was synthesized in essentially quantitative isotopic purity, and characterized by 1 H-NMR and mass spectroscopy. The title compound was found to be >98% pure by HPLC, and its retention time (t R 6.17 min) was less than that of an authentic clobazam standard (t R 6.32 min). Of the five steps in the synthesis of clobazam, the most susceptible to deuterium exchange was the nucleophilic substitution of 2,4-dichloronitrobenzene by aniline-d 7 to form N-(5-chloro-2-nitrophenyl)penta-deuteriophenylamine. In this step, the isotopic impurity aniline-2,3,4,5-d 5 introduced protons from nitrogen into the ortho and para positions of the deuteriophenyl ring of N-(5-chloro-2-nitrophenyl)pentadeuteriophenylamine. (author)

  7. CdBr2 complexes of 1,2-bis-[2-(5-H/methyl/chloro/nitro)-1H-benzimidazolyl]-1,2-ethanediols

    International Nuclear Information System (INIS)

    Aydin Tavman

    2005-01-01

    The complexes of 1,2-bis-[2-(5-H/methyl/chloro/nitro)-1H-benzimidazolyl]-1,2-ethanediols with CdBr 2 were synthesized and characterized by elemental analysis, molar conductivity, IR and NMR spectra. The ligands act as a bidentate only through both oxygen atoms of hydroxyl groups in complexes with ratio M:L=1:1 [ru

  8. Vilsmeier-Haack reagent: A facile synthesis of 2-(4-chloro-3,3-dimethyl-7-phenoxyindolin-2-ylidenemalonaldehyde and transformation into different heterocyclic compounds

    Directory of Open Access Journals (Sweden)

    Laya Roohi

    2013-10-01

    Full Text Available 2-(5-Chloro-2-phenoxyphenylhydrazine was converted to corresponding 3H-indole by Fischer method utilizing the isopropyl methyl ketone in acetic acid. The reaction of 3H-indole with Vilsmeier-Haack reagent furnished aminomethylene malonaldehyde in excellent yield while the reactions of malonaldehyde with hydrazine, arylhydrazines, amines, cyanoacetamide and hydroxylamine hydrochloride, led to the corresponding pyrazole derivatives, enamines, cyanopyridone, and cyanoacetamide derivatives respectively.

  9. Linking structure and vibrational mode coupling using high-resolution infrared spectroscopy: A comparison of gauche and trans 1-chloro-2-fluoroethane

    Science.gov (United States)

    Miller, C. Cameron; Stone, Stephen C.; Philips, Laura A.

    1995-01-01

    The high-resolution infrared spectrum of 1-chloro-2-fluoroethane in a molecular beam was collected over the 2975-2994 cm-1 spectral region. The spectral region of 2975-2981 cm-1 contains a symmetric C-H stretching vibrational band of the gauche conformer containing the 35Cl isotope. The spectral region of 2985-2994 cm-1 contains three vibrational bands of the trans conformer. Two of the three bands are assigned as an antisymmetric C-H stretch of each of the two different chlorine isotopes. The third band is assigned as a symmetric C-H stretch of the 35Cl isotope. The gauche conformer of 1-chloro-2-fluoroethane showed doublet patterns similar to those previously observed in 1,2-difluoroethane. The model for 1,2-difluoroethane is further refined in the present work. These refinements suggest that the coupling dark state in 1,2-difluoroethane is composed of 1 quantum C-H bend, 1 quantum C-C stretch, and 12 quanta of torsion. For 1-chloro-2-fluoroethane the dark state could not be identified due to a small data set. The trans conformer of 1-chloro-2-fluoroethane showed no evidence of mode coupling in the three vibrational bands. Including 2-fluoroethanol in this series of molecules, the extent of vibrational mode coupling did not correlate with the density of states available for coupling. Therefore, density of states alone is insufficient to explain the observed trend. A correlation was observed between the degree of intramolecular interaction and vibrational mode coupling.

  10. Diode laser slit-jet spectra and analysis of the fundamental of 1-chloro-1,1-difluoroethane (HCFC-142b)

    Science.gov (United States)

    Snels, M.; D'Amico, G.

    2002-11-01

    High resolution infrared spectra (0.001 cm^{-1}) have been measured for mixtures of 1-chloro-1,1-difluoroethane in Ne, expanded in a supersonic planar jet. The ν_7 fundamental has been analyzed for both isotopic species, CH3CF2 ^{35}Cl and CH3CF2 ^{37}Cl. A weak b-type component has been observed for the first time.

  11. Negative photoion spectroscopy of the core-excited bromo-chloro-alkanes, Br(CH2)nCl, n = 1-4

    International Nuclear Information System (INIS)

    Scully, S W J; Mackie, R A; Browning, R; Dunn, K F; Latimer, C J

    2004-01-01

    Polar photodissociation of a set of bromo-chloro-alkanes in the vicinity of the Br 3d core edge has been observed for the first time. It is shown that negative photoion spectroscopy is a powerful tool for investigating the various decay mechanisms of core-excited molecules. Analysis of these results indicates that the observed polar photodissociation arises from two competing spectator Auger decay processes in which the molecule can dissociate either before or after the core hole relaxation

  12. In-vitro antimicrobial screening and molecular docking studies of synthesized 2-chloro-N-(4-phenylthiazol-2-ylacetamide derivatives

    Directory of Open Access Journals (Sweden)

    Rahmat Ali

    2015-01-01

    Full Text Available Introduction: Glucosamine-6-phosphate (GlcN6P synthase biosynthetic pathway has been identified as potential targets for the development of new antimicrobial agents. Aim: A series of 2-chloro-N-(42-phenylthiazol-25-ylacetamide derivatives (3a-r was synthesized and evaluated their antimicrobial activity. Materials and Methods: The 2-chloro-N-(Para substituted phenylthiazol-25-yl acetamide (2a-c were synthesized by stirring intermediates (1a-c with 2-chloroacetylchloride in dichloromethane in the presence of K2CO3. The intermediate (2a-c were further reacted with different secondary amine such as pyrrolidine, N-methyl piperazine, N-ethyl piperazine, thiomorpholine, morpholine, piperidine etc in ethanol in presence of TEA Triethylamine (TEA to get desired compounds (3a-r. Compounds were characterized by a spectroscopic technique such as Fourier transform infraredFTIR, 1 H-NMR, 13 C-NMR, and mass spectrometry. The synthesized thiazole derivatives (3a-r were screened for anti-bacterial and anti-fungal activity against Escherichia coli, Staphylococcus aureus NCTC 6571, Pseudomonas aeruginosa NCTC 10662, CandidaC. albicans (MTCC-183, AspergillusA. niger (MTCC 281 NCTC 10418 and AspergillusA. flavus (MTCC 277. Result and Conclusion: The results of anti-bacterial screening revealed that among all the screened compounds, eight compounds viz. 3b, 3c, 3d, 3e, 3i, 3j, 3k, and 3p showed moderate to good anti-bacterial and antifungal activity having minimum inhibitory concentration (MIC between 6.25- and 25 µg/ml. While compound 3d showed the most promising antibacterial activity against E. coli and S. aureus, while the compound 3j showed promising antifungal activity with MIC value 6.25 µg/ml against C. albicans, A. niger and A. flavus. In addition, all these eight potential molecules were also examined for possible binding on enzyme GlcN6Pglucosamine-6-phosphate synthase by molecular docking studies on (PDB ID 1JXA.

  13. Catalytic hydroprocessing of lignin β-O-4 ether bond model compound phenethyl phenyl ether over ruthenium catalysts

    NARCIS (Netherlands)

    Gomez-Monedero, B.; Faria, J.; Bimbela, F.; Ruiz, M.P.

    2017-01-01

    The catalytic hydroprocessing of phenethyl phenyl ether (PPE), a model compound of one of the most significant ether linkages within lignin structure, β-O-4, has been studied. Reactions were carried out using two ruthenium-based catalysts, supported on different materials: 3.8 wt.% Ru/C and 3.9 wt.%

  14. Spectral Properties of Novel 1,3-oxazol-5(4H)-ones With Substituted Benzylidene and Phenyl Rings

    DEFF Research Database (Denmark)

    Palcut, Marián

    2009-01-01

    In the present work, five novel (4Z)-4-benzylidene-2-phenyl-1,3-oxazol-5(4H)-ones (azlactones) were investigated by the infra-red (IR) and nuclear magnetic resonance spectroscopy (NMR) of the 1H and 13C nuclei. The spectral properties of the oxazolone ring were monitored with respect to the subst...

  15. Antifouling phenyl ethers and other compounds from the invertebrates and their symbiotic fungi collected from the South China Sea.

    Science.gov (United States)

    Wang, Chao-Yi; Wang, Kai-Ling; Qian, Pei-Yuan; Xu, Ying; Chen, Min; Zheng, Juan-Juan; Liu, Min; Shao, Chang-Lun; Wang, Chang-Yun

    2016-12-01

    Marine organism-derived secondary metabolites are promising potential sources for discovering environmentally safe antifouling agents. In present study, 55 marine secondary metabolites and their synthesized derivatives were tested and evaluated for their antifouling activities and security. These compounds include 44 natural products isolated from marine invertebrates and their symbiotic microorganisms collected from the South China Sea and 11 structural modified products derived from the isolated compounds. The natural secondary metabolites, covering phenyl ether derivatives, terpenoids, 9, 11-secosteroids, anthraquinones, alkaloids, nucleoside derivatives and peptides, were isolated from two corals, one sponge and five symbiotic fungi. All of the isolated and synthesized compounds were tested for their antifouling activities against the cyprids of barnacle Balanus (Amphibalanus) amphitrite Darwin. Noticeably, five phenyl ether derivatives (9, 11, 13-15) exhibited potent anti-larval settlement activity with the EC 50 values lower than 3.05 μM and the LC 50 /EC 50 ratios higher than 15. The study of structure-activity relationship (SAR) revealed that the introduction of acetoxy groups and bromine atoms to phenyl ether derivatives could significantly improve their antifouling activities. This is the first report on the SAR of phenyl ether derivatives on antifouling activity against barnacle B. amphitrite. The polybrominated diphenyl ether derivative, 2, 4, 6, 2', 4', 6'-hexabromo-diorcinol (13), which displayed excellent antifouling activity, was considered as a promising candidate of environmentally friendly antifouling agents.

  16. 4-{[(1-Phenyl-1H-pyrazol-3-yloxy]methyl}-1,3-dioxolan-2-one

    Directory of Open Access Journals (Sweden)

    Algirdas Šačkus

    2012-11-01

    Full Text Available The title compound was obtained by the reaction of tosylated glycerol carbonate with 1-phenyl-1H-pyrazol-3-ol in a good 71% yield. Detailed spectroscopic data (1H-NMR, 13C-NMR, 15N-NMR, IR, MS are presented.

  17. 4-(ALPHA, ALPHA-DIMETHYLBENZYL)PHENYL METHACRYLATE .3. SYNTHESIS, TACTICITY AND GLASS-TRANSITION TEMPERATURES OF ITS POLYMERS

    NARCIS (Netherlands)

    VANEKENSTEIN, GORA; TAN, YY

    Depending on the kind of initiator, anionic Polymerization of 4-(alpha,alpha-dimethylbenzyl)phenyl methacrylate in toluene at -78-degrees-C led either to highly isotactic or predominantly syndiotactic polymers as determined by C-13 NMR spectro copy. The glass transition temperature difference

  18. NaSO2Ph Induced Exclusive Isomerization of 1,2-Allenyl Sulfoxides to 2-Alkynylic Phenyl Sulfoxides

    Institute of Scientific and Technical Information of China (English)

    傅春玲; 麻生明

    2005-01-01

    The clean isomerization of 1,2-allenyl sulfoxides in the presence of NaSO2Ph afforded 2-alkynylic phenyl sulfoxides in good yields and selectivities. Although strong base-catalyzed isomerization of allenes to alkynes is known, the mechanism for the current reaction is interesting for the obvious reason that NaSOEPh is a weak base.

  19. Some New Routes for the Preparation of 3-Amino-2-phenyl-4(1H)-quinolinones from Anthranilamides

    Czech Academy of Sciences Publication Activity Database

    Hradil, P.; Grepl, M.; Hlaváč, J.; Soural, M.; Maloň, Michal; Bertolasi, V.

    2006-01-01

    Roč. 71, č. 2 (2006), s. 819-822 ISSN 0022-3263 Institutional research plan: CEZ:AV0Z50380511 Keywords : RESONANCE * 3-amino-2-phenyl-4-1(H)-quinolinone * quinolinones 7 Subject RIV: CE - Biochemistry Impact factor: 3.790, year: 2006

  20. Antifouling phenyl ethers and other compounds from the invertebrates and their symbiotic fungi collected from the South China Sea

    KAUST Repository

    Wang, Chao-Yi

    2016-10-26

    Marine organism-derived secondary metabolites are promising potential sources for discovering environmentally safe antifouling agents. In present study, 55 marine secondary metabolites and their synthesized derivatives were tested and evaluated for their antifouling activities and security. These compounds include 44 natural products isolated from marine invertebrates and their symbiotic microorganisms collected from the South China Sea and 11 structural modified products derived from the isolated compounds. The natural secondary metabolites, covering phenyl ether derivatives, terpenoids, 9, 11-secosteroids, anthraquinones, alkaloids, nucleoside derivatives and peptides, were isolated from two corals, one sponge and five symbiotic fungi. All of the isolated and synthesized compounds were tested for their antifouling activities against the cyprids of barnacle Balanus (Amphibalanus) amphitrite Darwin. Noticeably, five phenyl ether derivatives (9, 11, 13–15) exhibited potent anti-larval settlement activity with the EC50 values lower than 3.05 μM and the LC50/EC50 ratios higher than 15. The study of structure–activity relationship (SAR) revealed that the introduction of acetoxy groups and bromine atoms to phenyl ether derivatives could significantly improve their antifouling activities. This is the first report on the SAR of phenyl ether derivatives on antifouling activity against barnacle B. amphitrite. The polybrominated diphenyl ether derivative, 2, 4, 6, 2′, 4′, 6′-hexabromo-diorcinol (13), which displayed excellent antifouling activity, was considered as a promising candidate of environmentally friendly antifouling agents.

  1. Inhibitors of inosine monophosphate dehydrogenase: SARs about the N-[3-Methoxy-4-(5-oxazolyl)phenyl moiety.

    Science.gov (United States)

    Iwanowicz, Edwin J; Watterson, Scott H; Guo, Junqing; Pitts, William J; Murali Dhar, T G; Shen, Zhongqi; Chen, Ping; Gu, Henry H; Fleener, Catherine A; Rouleau, Katherine A; Cheney, Daniel L; Townsend, Robert M; Hollenbaugh, Diane L

    2003-06-16

    The first reported structure-activity relationships (SARs) about the N-[3-methoxy-4-(5-oxazolyl)phenyl moiety for a series of recently disclosed inosine monophosphate dehydrogenase (IMPDH) inhibitors are described. The syntheses and in vitro inhibitory values for IMPDH II, and T-cell proliferation (for select analogues) are given.

  2. Synthesis of 2-phenyl-1,2-benziso[77Se]selenazol-3(2H)-one: ''Ebselen''

    International Nuclear Information System (INIS)

    Oppenheimer, Jossian; Silks, L.A. III

    1996-01-01

    Synthesis of 2-Phenyl-1,2-benziso[ 77 Se]selenazol-3(2H)-one has been accomplished in one step from 94% 77 Se and commercially available starting materials in 76% yield based on the enriched elemental selenium. (author)

  3. 5-(4-Methoxyphenyl-4-methyl-1-phenyl-3-p-tolyl-1H-pyrazole

    Directory of Open Access Journals (Sweden)

    Yahya Ben Soumane

    2017-11-01

    Full Text Available The title compound, C24H22N2O, crystallizes with two independent molecules (A and B in the asymmetric unit. The phenyl, p-tolyl and p-methoxyphenyl rings are inclined to the pyrazole ring by 42.5 (2, 17.68 (19 and 52.20 (19°, respectively, in molecule A, and by 39.5 (2, 40.77 (19 and 59.76 (18°, respectively, in molecule B. In the asymmetric unit, the pyrarole ring of molecule A makes a dihedral angle of 3.7 (2° with that of molecule B. In the crystal, the two independent molecules are linked to each other by a C—H...O hydrogen bond.

  4. Kinetics and Mechanism of Nanoparticles-Catalyzed Piperidinolysis of Anionic Phenyl Salicylate

    Directory of Open Access Journals (Sweden)

    Norazizah Abd. Razak

    2014-01-01

    Full Text Available The values of the relative counterion (X binding constant RXBr (=KX/KBr, where KX and KBr represent cetyltrimethylammonium bromide, CTABr, micellar binding constants of Xv- (in non-spherical micelles, v=1,2, and Br− (in spherical micelles are 58, 68, 127, and 125 for Xv−=1−, 12−, 2−, and 22-, respectively. The values of 15 mM CTABr/[NavX] nanoparticles-catalyzed apparent second-order rate constants for piperidinolysis of ionized phenyl salicylate at 35°C are 0.417, 0.488, 0.926, and 0.891 M−1 s−1 for NavX = Na1, Na21, Na2, and Na22, respectively. Almost entire catalytic effect of nanoparticles catalyst is due to the ability of nonreactive counterions, Xv-, to expel reactive counterions, 3−, from nanoparticles to the bulk water phase.

  5. Cardiac metabolism of 15 (p-I-123 phenyl-) pentadecanoic acid after intracoronary tracer application

    Energy Technology Data Exchange (ETDEWEB)

    Reske, S.N.; Reichmann, K.; Knopp, R.; Winkler, C.; Koischwitz, D.; Machulla, H.J.; Simon, H.

    1984-05-01

    Myocardial turnover of ..omega..-(p/sup 123/I-Phenyl-) pentadecanoic acid and release of its metabolites into the coronary sinus and peripheral blood has been studied in patients with coronary artery and valvular heart disease. After intracoronary tracer injection myocardial extraction fractions of 45-53% in control subjects were observed. In patients with coronary artery disease (CAD) normal to reduced values (34-61%) were established. Hydrophilic catabolites of I-PPA, probably p/sup 123/I-benzoic and -hippuric acid as well as small amounts of the non-metabolized tracer were found in coronary sinus and peripheral blood. Myocardial tracer uptake and clearance patterns were clearly different in normal myocardium when compared to that obtained in patients with CAD. Thus, evaluation of myocardial I-PPA metabolism might provide a new diagnostic tool for assessment of integrity of the heart's muscular metabolic function.

  6. New phenyl derivatives from endophytic fungus Aspergillus flavipes AIL8 derived of mangrove plant Acanthus ilicifolius.

    Science.gov (United States)

    Bai, Zhi-Qiang; Lin, Xiuping; Wang, Yizhu; Wang, Junfeng; Zhou, Xuefeng; Yang, Bin; Liu, Juan; Yang, Xianwen; Wang, Yi; Liu, Yonghong

    2014-06-01

    Two new aromatic butyrolactones, flavipesins A (1) and B (2), two new natural products (3 and 4), and a known phenyl dioxolanone (5) were isolated from marine-derived endophytic fungus Aspergillus flavipes. The structures of compounds 1-5 were elucidated by 1D- and 2D-NMR and MS analysis, the absolute configurations were assigned by optical rotation and CD data, and the stereochemistry of 1 was determined by X-ray crystallography analysis. 1 demonstrated lower MIC values against Staphylococcus aureus (8.0 μg/mL) and Bacillus subtillis (0.25 μg/mL). 1 also showed the unique antibiofilm activity of penetration through the biofilm matrix and kills live bacteria inside mature S. aureus biofilm. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Solvent extraction of gold(III) with 1-phenyl-3-methyl-4-trifluoroacetylpyrazolone-5

    International Nuclear Information System (INIS)

    Hasany, S.M.; Imtiaz Hanif

    1978-01-01

    A simple, rapid and selective separation procedure of gold based on its extraction with 1-phenyl-3-methyl-4-trifluoroacetylpyrazolone-5 has been developed. The dependence of the distribution ratio of gold on the pH of aqueous solutions, concentration of hydrochloric, nitric and perchloric acids and the organic solvents has been investigated. Decontamination factors for a number of metal ions with respect to gold are reported. Excellent separation of gold is obtained from many elements including noble metals. Citrate, cyanide, iodide, thiosulfate and thiourea completely mask gold, whereas oxalate does not interfere. Solutions of 1M HCl, 0.2M KCN, and the buffer of pH 0.8 readily strip gold from the organic phase. Some useful analytical applications of this procedure are discussed. (author)

  8. Nucleophilic reactions of hydrazido(2-) complexes of molybdenum and tungsten with succinyl dichloride and phenyl isocyanate

    International Nuclear Information System (INIS)

    Iwanami, Kiyotaka; Mizobe, Yasushi; Takahashi, Tamotsu; Kodama, Teruyuki; Uchida, Yasuzo

    1981-01-01

    Nucleophilic attack of the WNNH 2 group in the hydrazido(2-) complex [WF(NNH 2 )(dpe) 2 ][BF 4 ] (dpe = Ph 2 PCH 2 CH 2 PPh 2 ) on succinyl dichloride gives a novel ethanedioylhydrazido(2-) complex, [WF(NNCOCH 2 CH 2 CO)(dpe) 2 ][BF 4 ]. X-Ray structural analysis shows that the carbon, nitrogen, and oxygen atoms of the ethanedioylhydrazido(2-) ligand lie nearly in the same plane, indicating sp 2 character of the nitrogen atom bearing the two carbonyl groups. Phenyl isocyanate also undergoes nucleophilic attack by the hydrazido(2-) complex [MBr(NNH 2 )(dpe) 2 ]Br (M = Mo or W) to yield the phenylsemicarbazido(2-) type complex, [MBr(NNHCONHPh)(dpe) 2 ]Br. Treatment of the semicarbazido(2-) complex with triethylamine gives a new diazenido complex [MBr(NNCONHPh)(dpe) 2 ]. (author)

  9. Photochemistry and reactivity of the phenyl radical-water system: a matrix isolation and computational study.

    Science.gov (United States)

    Mardyukov, Artur; Crespo-Otero, Rachel; Sanchez-Garcia, Elsa; Sander, Wolfram

    2010-08-02

    The reaction of the phenyl radical 1 with water has been investigated by using matrix isolation spectroscopy and quantum chemical calculations. The primary thermal product of the reaction between 1 and water is a weakly bound complex stabilized by an OH...pi interaction. This complex is photolabile, and visible-light irradiation (lambda>420 nm) results in hydrogen atom transfer from water to radical 1 and the formation of a highly labile complex between benzene and the OH radical. This complex is stable under the conditions of matrix isolation, however, continuous irradiation with lambda>420 nm light results in the complete destruction of the aromatic system and formation of an acylic unsaturated ketene. The mechanisms of all reaction steps are discussed in the light of ab initio and DFT calculations.

  10. 1-Phenyl-5-{[2-(trimethylsilylethyl]sulfonyl}-1H-tetrazole

    Directory of Open Access Journals (Sweden)

    David Tymann

    2011-09-01

    Full Text Available The title compound, C12H18N4O2SSi, was synthesized to be employed in a Julia–Kocieński olefination. In the molecule, the dihedral angle between the phenyl ring and the tetrazole ring is 41.50 (5°. The significantly longer Si—C(methylene bond [1.8786 (13 Å] and the shortened adjacent C—C bond [1.5172 (18 Å], as well as the significant deviation of the corresponding Si—C—C angle [114.16 (9°] from the ideal tetrahedral angle, can be attributed to the β-effect of silicon. In the crystal, molecules are held together by van der Waals interactions.

  11. Synergistic extraction of trivalent lanthanoids with 3-phenyl-4-benzoyl-5-isoxazolone and various sulphoxides

    International Nuclear Information System (INIS)

    Sahu, S.K.; Chakravortty, V.; Reddy, M.L.P.; Ramamohan, T.R.

    1999-01-01

    Synergistic extraction of trivalent lanthanoids Nd, Tb and Tm with mixtures of 3-phenyl-4-benzoyl-5-isoxazolone (HPBI) and dioctyl sulphoxide (DOSO), bis-2-ethylhexyl sulphoxide (B2EHSO) or diphenyl sulphoxide (DPhSO) in xylene from perchlorate solution was investigated. Lanthanoids were found to be extracted as Ln(PBI) 3 with HPBI alone. In the presence of sulphoxides, Nd(III) was found to be extracted as Nd(PBI) 3 . S and Nd(PBI) 3 . 2 S (where S = sulphoxide). On the other hand, Tb(III) and Tm(III) were extracted as Tb(PBI) 3 . S and Tm(PBI) 3 . S respectively. The equilibrium constants of the synergistic species were found to increase monotonically with decreasing ionic radii of these metal ions. The addition of a sulphoxide to the metal chelate system not only enhances the extraction efficiency but also improves the selectivities among these trivalent lanthanoids. (orig.)

  12. Hybrid Detectors for Neutrons Combining Phenyl- Polysiloxanes with 3D Silicon Detectors

    International Nuclear Information System (INIS)

    Dalla Palma, Matteo; Quaranta, Alberto; Collazuol, Gianmaria; Carturan, Sara; Cinausero, Marco; Gramegna, Fabiana; Marchi, Tommaso; Dalla Betta, Gian-Franco; Mendicino, Roberto; Povoli, Marco; Boscardin, Maurizio; Giacomini, Gabriele; Ronchin, Sabina; Zorzi, Nicola

    2013-06-01

    We report on the initial results of a research project aimed at the development hybrid detectors for fast neutrons by combining a phenyl-polysiloxane-based converter with a 3D silicon detector. To this purpose, new 3D sensor structures have been designed, fabricated and electrically tested, showing low depletion voltage and good leakage current. Moreover, the radiation detection capability of 3D sensors was tested by measuring the signals recorded from alpha particles, gamma rays, and pulsed lasers. The converter has been poured into the 3D cavities with excellent coupling, as confirmed by cross-section SEM analyses. Preliminary tests with neutrons have been carried out on the first hybrid detector prototypes at the CN accelerator of INFN LNL. The device design and technology are discussed, along with the first results from the electrical and functional characterization. (authors)

  13. 3-Phenyl-6-(2-pyridyl-1,2,4,5-tetrazine

    Directory of Open Access Journals (Sweden)

    Daniel Chartrand

    2008-01-01

    Full Text Available The title compound, C13H9N5, is the first asymmetric diaryl-1,2,4,5-tetrazine to be crystallographically characterized. We have been interested in this motif for incorporation into supramolecular assemblies based on coordination chemistry. The solid state structure shows a centrosymmetric molecule, forcing a positional disorder of the terminal phenyl and pyridyl rings. The molecule is completely planar, unusual for aromatic rings with N atoms in adjacent ortho positions. The stacking observed is very common in diaryltetrazines and is dominated by π stacking [centroid-to-centroid distance between the tetrazine ring and the aromatic ring of an adjacent molecule is 3.6 Å, perpendicular (centroid-to-plane distance of about 3.3 Å].

  14. Determination of aliphatic amines in mineral flotation liquors and reagents by high-performance liquid chromatography after derivatization with 4-chloro-7-nitrobenzofurazan.

    Science.gov (United States)

    Hao, F; Lwin, T; Bruckard, W J; Woodcock, J T

    2004-11-05

    The method described here fulfils the need for a suitable analytical method to determine the concentrations of single and mixed aliphatic amines in the range from hexylamine (C6) to octadecylamine (C18) in flotation test solutions and in commercial flotation collectors. Amines do not have a UV-vis spectrum in aqueous solution but by reacting an amine-containing solution with 4-chloro-7-nitrobenzofurazan solution (chloro-NBD), derivatized products (amino-NBDs) are formed which have absorbance maxima at 470nm. Excess chloro-NBD and the amino-NBDs can be separated from each other by high-performance liquid chromatography (HPLC) and their concentrations measured with a UV-vis detector. Important variables in the derivatization stage are pH, temperature, chloro-NBD concentration, and reaction time, all of which interact with each other. A three-stage statistical procedure was used to determine the optimum conditions. In each stage, an 8-test design was used in which a high and low limit was set for each variable, and the chromatogram peak area of the derived amino-NBD was measured. The optimum derivatization conditions established were pH 8.9, chloro-NBD concentration 0.20% (w/v), temperature 70 degrees C, and reaction time 60 min. Optimum elution conditions for chromatography were an eluent containing 80% (v/v) acetonitrile in aqueous solution containing 40mM acetic acid at pH 4.5. With a flow rate of 2.0 ml/min, dodecylamine had a retention time of about 3 min, whereas octadecylamine had a retention time of 44 min. Straight-line calibration curves were obtained up to at least 200 ppm of amine in solution. The lower limit of detection was estimated to be 0.05 microM (10ppb) with a signal to noise ratio of 3. No interfering substances were found. The method was successfully applied to the analysis of solutions from an actual flotation test and to a solid commercial amine.

  15. Radiation sensitization of Escherichia coli B/r by 2'-chloro-2'-deoxythymidine under various irradiation conditions

    International Nuclear Information System (INIS)

    Hayashi, M.; Kuwabara, M.; Sato, F.; Itoh, T.

    1985-01-01

    Marked sensitization of E. coli cells by 2'-chloro-2'-deoxythymidine to x-rays was observed, when E. coli cells labelled with 2' Cl-TdR were exposed to x-rays in the absence and presence of oxygen. The sensitization factor calculated from inactivation constants from survival curves irradiated in the absence of 0 2 was about half that obtained in its presence. When 2'Cl-TdR was not incorporated into the DNA of E. coli cells, the presence of 2'Cl-TdR in the cell suspension fluid at the time of irradiation caused no sensitization. The sensitization factor for 2'Cl-TdR obtained under N 2 O was almost the same as that obtained under N 2 . The sensitization factor obtained in the presence of glycerol at 1 mol dm -3 under N 2 was similar to that obtained in its presence. These results indicated that the radical at the C-2' position of the deoxyribose moiety in DNA produced by x-irradiation was transformed into lethal damage for E. coli cells even in the absence of O 2 , though more efficiently in its presence. (U.K.)

  16. Sulfonation of PEEK-WC polymer via chloro-sulfonic acid for potential PEM fuel cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Iulianelli, A.; Clarizia, G.; Gugliuzza, A.; Ebrasu, D.; Basile, A. [Institute on Membrane Technology, ITM-CNR, c/o University of Calabria, Via P. Bucci, Cubo 17/C, 87030 Rende (CS) (Italy); Bevilacqua, A. [Research Centre Italsistemi S.r.l., Via Avogadro, 88900 Crotone (KR) (Italy); Trotta, F. [Department of Organic Chemistry, University of Torino, C.So M. D' Azeglio 48, 10125 Torino (TO) (Italy)

    2010-11-15

    The preparation and characterization of thin dense sulfonated poly-ether-ether-ketone with cardo group (PEEK-WC) membranes for proton exchange membrane fuel cell (PEMFC) applications are described. The sulfonation of PEEK-WC polymer was realized via chloro-sulfonic acid and different kinds of membrane samples were prepared with a sulfonation degree ranging from 67 to 99%. The degree of sulfonation, homogeneity and thickness significantly affect both the membrane transport properties and the electrochemical performances. The dense character of the membranes was confirmed by SEM analysis. Proton conductivity measurements were carried out in a temperature range from 30 to 80 C and at 100% of relative humidity, reaching 5.40 x 10{sup -3} S/cm{sup -1} as best value at 80 C and with a sulfonation degree (DS) of 99%. At the same conditions, a water uptake of 17% was achieved. DSC and TGA characterizations were used in order to determine the thermal stability of the membranes, confirming a T{sub g} ranging between 206 and 216 C depending on the DS, whereas FT-IR yielded indication about intermolecular interactions and water uptake at various sulfonation degrees. (author)

  17. Degradation of 4-chloro 2-aminophenol using a novel combined process based on hydrodynamic cavitation, UV photolysis and ozone.

    Science.gov (United States)

    Barik, Arati J; Gogate, Parag R

    2016-05-01

    The degradation of 4-chloro 2-aminophenol (4C2AP), an acute toxic organic compound, has been studied using different approaches based on the hydrodynamic cavitation (HC) with orifice plate as cavitating device, photolysis (UV) and ozonation (O3). The dependency of extent of degradation on operating parameters like operating pressure (2-5 bar), initial pH (3-8) and temperature (30-38 °C) have been established initially to maximize the efficacy of hydrodynamic cavitation. Subsequently the degradation has been studied using combined treatment strategies as HC+UV, HC+O3, UV+O3 and HC+UV+O3 at the established optimum parameters of operating temperature as 30 °C, initial pH of 6 and inlet pressure of 4 bar. The maximum extent of degradation as 96.85% and 73.6% reduction in TOC has been obtained using hydrodynamic cavitation in combination with UV photolysis and ozonation under the optimized operating conditions. The degradation products of 4C2AP have been identified using GC-MS. The present work has clearly established the efficacy of combined treatment approach (HC+UV+O3) for the removal of organic pollutant for the first time. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Vibrational spectroscopic, structural and nonlinear optical activity studies on 2-amino-3-chloro-5-trifluoromethyl pyridine: A DFT approach

    Science.gov (United States)

    Asath, R. Mohamed; Premkumar, S.; Rekha, T. N.; Jawahar, A.; Mathavan, T.; Benial, A. Milton Franklin

    2016-05-01

    The conformational analysis was carried out for 2-amino-3-chloro-5-trifluoromethylpyridine using potential energy surface (PES) scan and the most stable optimized conformer was predicted. The theoretical vibrational frequencies were calculated for the optimized geometry using DFT/B3LYP cc-pVQZ basis set by Gaussian 09 Program. The vibrational frequencies were assigned on the basis of potential energy distribution calculation using VEDA 4.0 program package. The Mulliken atomic charge values were calculated. In the Frontier molecular orbitals analysis, the molecular reactivity, kinetic stability, intermolecular charge transfer studies and the calculation of ionization energy, electron affinity, global hardness, chemical potential, electrophilicity index and softness of the molecule were carried out. The nonlinear optical (NLO) activity was studied and the first order hyperpolarizability value was computed, which was 3.48 times greater than the urea. The natural bond orbital analysis was also performed to confirm the NLO activity of the molecule. Hence, the ACTP molecule is a promising candidate for NLO materials.

  19. Fluorimetric determination of proteins using 4-chloro-(2'-hydroxylophenylazo)rhodanine-Ti(IV) complex as a spectral probe.

    Science.gov (United States)

    Sun, Shuting; Ma, Hongmin; Chen, Xin; Zhang, Nuo; Wu, Dan; Du, Bin; Wei, Qin

    2008-01-01

    A novel method for the determination of proteins was developed, based on the enhancement of fluorescence with 4-chloro-(2'-hydroxylophenylazo)rhodanine-Ti(IV) [ClHARP-Ti(IV)] complex as a fluorescence probe. The excitation and emission wavelengths of the system were 335 nm and 376 nm, respectively. The presence of bis(2-ethylhexyl)sulphosuccinate sodium salt (AOT) microemulsion greatly increased the sensitivity of the system. Under optimal conditions, four kinds of proteins, including bovine serum albumin (BSA), human serum albumin (HSA), egg albumin (Ova), and gamma-globin (gamma-G) were studied. The detection limits were 0.182 microg/mL for BSA, 0.0788 microg/mL for HSA, 0.216 microg/mL for Ova and 0.484 microg/mL for gamma-G. The linear ranges of the calibration were 0-12.0, 0-10.0, 0-18.0 and 0-18.0 microg/mL, respectively. The method possessed high sensitivity, good selectivity and was applied to the analysis of protein in milk powder and cornmeal with satisfactory results.

  20. Session 6: Liquid-phase chloro-benzene hydrogenolysis over alkali-doped zirconia supported palladium catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Aramendia, M.A.; Borau, V.; Jimenez, C.; Marinas, A.; Marinas, J.M.; Moreno, J.M.; Ruiz, J.R.; Urbano, F.J. [University of Cordoba. Marie Curie Building, Dept. of Organic Chemistry (Spain)

    2004-07-01

    Chlorinated hydrocarbons constitute one of the most important kind of organic pollutants due to their environmental impact and noxious effects. Catalytic hydro-dehalogenation is now emerging as a promising non-destructive alternative technology whereby the chlorinated waste is converted to products with a commercial value. It is simple, safe, effective, and it ensures, in many instances, the regeneration of the initial raw material. One of the main problems of catalytic hydro-dehalogenation arise from the deactivating effect of the hydrogen halide released as by product. This can be surpassed by, for example, adding a base, such as NaOH, or modification of the catalyst in order to neutralize the hydrogen halide released. In conclusion, the alkali modification of the zirconia supported catalysts did not enhance the catalytic activity in comparison to the undoped Pd/ZrO{sub 2}. Moreover, the lithium doped catalyst exhibits very poor results in initial rate and final chloro-benzene conversion. This could be related to the reduction in BET surface area caused by the doping together with a lower enhancement of the surface basicity of the doped catalysts. (authors)

  1. Physico-chemical studies of the experimental and theoretical properties of organic nonlinear optical material 4-chloro-4'methoxy benzylideneaniline

    Science.gov (United States)

    George, Merin; John, Nimmy L.; Saravana Kumar, M.; Subashini, A.; Sajan, D.

    2017-01-01

    The FT-IR, FT-Raman and UV-visible spectral analysis of 4-chloro 4'-methoxy benzylidene aniline were done experimentally and interpreted with the aid of normal coordinate analysis based on density functional theory (DFT) at the B3LYP/6-311++G (d, p) level of theory. Natural Bond orbital analysis was performed to understand the charge transfer interactions and reactive sites within the system. HOMO-LUMO analysis and first static and dynamic hyperpolarizability calculations were carried out in order to confirm the NLO activity of CMOBA. Photophysical characterization was done to understand the fluorescence emission and lifetime of CMOBA leading to application in blue OLEDs. The Molecular Electrostatic Potential Map was simulated to identify the active sites for electrophilic and nucleophilic attack or the active sites of the molecule which can bind to proteins. Molecular docking analysis revealed its potential as an inhibitor for different proteins which are responsible for cancer and many inflammatory diseases such as rheumatoid arthritis, inflammatory bowel disease, Crohn's disease and psoriasis. Experimental studies of invitro antiproliferative effect by MTT assay verified the anticancer properties of CMOBA.

  2. Exposure of Human Lung Cancer Cells to 8-Chloro-Adenosine Induces G2/M Arrest and Mitotic Catastrophe

    Directory of Open Access Journals (Sweden)

    Hong-Yu Zhang

    2004-11-01

    Full Text Available 8-Chloro-adenosine (8-CI-Ado is a potent chemotherapeutic agent whose cytotoxicity in a variety of tumor cell lines has been widely investigated. However, the molecular mechanisms are uncertain. In this study, we found that exposure of human lung cancer cell lines A549 (p53-wt and H1299 (p53-depleted to 8-CI-Ado induced cell arrest in the G2/M phase, which was accompanied by accumulation of binucleated and polymorphonucleated cells resulting from aberrant mitosis and failed cytokinesis. Western blotting showed the loss of phosphorylated forms of Cdc2 and Cdc25C that allowed progression into mitosis. Furthermore, the increase in Ser10-phosphorylated histone H3-positive cells revealed by fluorescence-activated cell sorting suggested that the agent-targeted cells were able to exit the G2 phase and enter the M phase. Immunocytochemistry showed that microtubule and microfilament arrays were changed in exposed cells, indicating that the dynamic instability of microtubules and microfilaments was lost, which may correlate with mitotic dividing failure. Aberrant mitosis resulted in mitotic catastrophe followed by varying degrees of apoptosis, depending on the cell lines. Thus, 8-CI-Ado appears to exert its cytotoxicity toward cells in culture by inducing mitotic catastrophe.

  3. A theoretical study on 2-chloro-5-(2-hydroxyethyl-4-methoxy-6-methylpyrimidine by DFT/ab initio calculations

    Directory of Open Access Journals (Sweden)

    Gümüs Hacer Pir

    2015-06-01

    Full Text Available Quantum chemical calculations have been performed to study the molecular geometry, 1H and 13C NMR chemical shifts, conformational, natural bond orbital (NBO and nonlinear optical (NLO properties of the 2-chloro-5-(2-hydroxyethyl-4- methoxy-6-methylpyrimidine molecule in the ground state using DFT and HF methods with 6-311++G(d,p basis set. The optimized geometric parameters and 1H and 13C NMR chemical shifts have been compared with the experimental values of the title molecule. The results of the calculations show excellent agreement between the experimental and calculated frequencies at B3LYP/6-311++G(d,p level. In order to provide a full understanding of the properties of the title molecule in the context of molecular orbital picture, the highest occupied molecular energy level (EHOMO, the lowest unoccupied molecular energy level (ELUMO, the energy difference (DE between EHOMO and ELUMO, electronegativity (χ, hardness (η and softness (S have been calculated using B3LYP/6-311++G(d,p and HF/6-311++G(d,p levels. The calculated HOMO and LUMO energies show that the charge transfer occurs within the title molecule.

  4. Spectrophotometric methods for the determination of ampicillin by potassium permanganate and 1-chloro-2,4-dinitrobenzene in pharmaceutical preparations

    Directory of Open Access Journals (Sweden)

    Aftab Aslam Parwaz Khan

    2015-03-01

    Full Text Available Two simple and sensitive kinetic methods for the determination of ampicillin (AMP are described. The first method is based on kinetic investigation of the oxidation reaction of the drug with alkaline potassium permanganate at room temperature for a fixed time of 25 min. The absorbance of the colored manganate ions is measured at 610 nm. The second method is based on the reaction of AMP with 1-chloro-2,4-dinitrobenzene (CDNB in the presence of 0.1 mol L−1 sodium bicarbonate. Spectrophotometric measurement was achieved by recording the absorbance at 490 nm for a fixed time of 60 min. All variables affecting the development of the color were investigated and the conditions were optimized. Plots of absorbance against concentration in both procedures were rectilinear over the ranges 5–30 and 50–260 μg mL−1, with mean recoveries 99.80 and 99.91, respectively. The proposed methods were successfully applied for the determination of AMP in bulk powder and in capsule dosage form. The determination of AMP by the fixed concentration method is feasible with the calibration equations obtained, but the fixed time method proves to be more applicable.

  5. Methylene blue and 4-chloro phenol degradation by photo catalysis with ultraviolet light, using TiO2 as catalyst

    International Nuclear Information System (INIS)

    Martinez H, A.

    2010-01-01

    Within the decontamination and remediation processes of the contaminated waters, as the refining or tertiary processes are the Advanced Oxidation Technologies. Among this technology is the heterogeneous photo catalysis, which is the object of this work to de grate 4-chloro phenol and methylene blue, using as semiconductor commercial titanium dioxide (TiO 2 ). On the degradation the combination is exposed in the use of TiO 2 under gamma irradiation of 60 Co at different doses 400, 500, 800, 1000 and 1500 kGy. The organic compounds degradation was determined and the results show that to more radiation dose, the material is modified in such way that shows a major absorption of the organic compound, in the same way it is determined that to more dose which undergoes the TiO 2 generally a major degradation is observed, but also it is has to give a more time of previous stabilization, for that the degradation is observed of better way. (Author)

  6. Rapid-mix studies on the anomalous radiosensitization of mammalian cells by 5-chloro-1-methyl-4-nitroimidazole

    International Nuclear Information System (INIS)

    Watts, M.E.; Hodgkiss, R.J.; Sehmi, D.S.; Woodcock, M.

    1980-01-01

    It has been suggested that the anomalously high radiosensitization shown by 5-chloro-1-methyl-4-nitroimidazole (CMNI) arises from dissociation of the CMNI radical-anion, yielding Cl - and an arylating free radical, and that the importance of this dehalogenation process could be investigated by irradiating hypoxic mammalian cells in vitro in the presence of CMNI, followed by the rapid addition of oxygen to prevent the dehalogenation process. 0.1 mmol dm -3 CMNI gave a sensitizer enhancement ratio (SER) of 1.7 when irradiated under steady-state conditions with 250 kVp X-rays (dose rate 3.93 Gymin -1 ) using V79 379A cells. Irradiation with 2.5 MeV electrons in the rapid-mix apparatus with 0.15 mmol dm -3 CMNI flowing through both tubes gave a slightly lower value, SER=1.5, in hypoxia. When air- or oxygen saturated 0.15 mmol dm -3 CMNI in Eagle's MEM were added to cells irradiated in hypoxic 0.15 mmol dm -3 CMNI solution 17 ms after irradiation, no change in SER was observed. Control experiments without CMNI also confirmed that the addition of oxygen at this time has no influence on radiosensitization. It was concluded that since a significant reduction in SER was not observed, the elimination of the ortho-substituted 'leaving group' is not responsible for the anomalously high radiosensitization efficiency. (U.K.)

  7. Enhanced degradation and mineralization of 4-chloro-3-methyl phenol by Zn-CNTs/O3 system.

    Science.gov (United States)

    Liu, Yong; Zhou, Anlan; Liu, Yanlan; Wang, Jianlong

    2018-01-01

    A novel zinc-carbon nanotubes (Zn-CNTs) composite was prepared, characterized and used in O 3 system for the enhanced degradation and mineralization of chlorinated phenol. The Zn-CNTs was characterized by SEM, BET and XRD, and the degradation of 4-chloro-3-methyl phenol (CMP) in aqueous solution was investigated using Zn-CNTs/O 3 system. The experimental results showed that the rate constant of total organic carbon (TOC) removal was 0.29 min -1 , much higher than that of only O 3 system (0.059 min -1 ) because Zn-CNTs/O 2 system could generate H 2 O 2 in situ, the concentration of H 2 O 2 could reach 156.14 mg/L within 60 min at pH 6.0. The high mineralization ratio of CMP by Zn-CNTs/O 3 occurred at wide pH range (3.0-9.0). The increase of Zn-CNTs dosage or gas flow rate contributed to the enhancement of CMP mineralization. The intermediates of CMP degradation were identified and the possible degradation pathway was tentatively proposed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Effects of Acupuncture on 1-chloro-2,4-dinitrochlorobenzene-induced Allergic Contact Dermatitis in Mice

    Directory of Open Access Journals (Sweden)

    Cuicui Chen

    2017-08-01

    Full Text Available Allergic contact dermatitis (ACD is a chronic inflammatory skin disease. Topical corticosteroids are the first-line therapy for ACD despite their significant adverse effects. Acupuncture has been widely used in the treatment of various skin diseases, but its underlying mechanism remains unrevealed. In this study, we investigated the characteristics of acupuncture treatment based on effectiveness and mechanism. BALB/c mice received 1-chloro-2,4-dinitrobenzene (DNCB application to build AD-like model. Results showed that acupuncture was an effective treatment method in inhibiting inflammatory conditions, serum IgE levels, and expression of proinflammatory cytokine Th2 (IL-4, IL-6, and Th2 (IL-1β, TNF-α mRNA compared with DNCB treatment. Acupuncture treatment also inhibited nuclear factor-κB p65, phosphorylation of IκBα, and phosphorylation of occludin proteins expression. Furthermore, it could improve the expression of epidermal growth factor in both mRNA and protein levels. These results suggest that acupuncture, as an alternative therapy treatment for its no significant side effects, was effective in alleviating ACD by reducing proinflammatory cytokines and changing proteins' expression.

  9. Allergic Potential and Immunotoxicity Induced by Topical Application of 1-Chloro-4-(Trifluoromethyl)Benzene (PCBTF) in a Murine Model

    Science.gov (United States)

    Franko, Jennifer; Jackson, Laurel G.; Meade, B. Jean; Anderson, Stacey E.

    2011-01-01

    The purpose of the studies in this paper was to evaluate the allergic potential, immunotoxicity, and irritancy of the occupationally relevant chemical, 1-chloro-4-(trifluoromethyl)benzene, also known as parachlorobenzotrifluoride (PCBTF), following dermal exposure in a murine model. Evaluation of the sensitization potential, conducted using the local lymph node assay (LLNA) at concentrations ranging from 50% to 100%, identified a dose-dependent increase in lymphocyte proliferation with a calculated EC3 value of 53.1%. While no elevations in total or specific IgE were observed after exposure to any concentration of the chemical, significant increases in IFN-γ protein production by stimulated draining lymphoid cells were observed, indicating a T-cell-mediated response. Dermal exposure to PCBTF was not found to alter the immune response to a T-cell-dependant antigen. These results demonstrate that PCBTF has the potential to induce allergic sensitization following dermal exposure and based on LLNA results would be classified as a weak sensitizer. PMID:21747864

  10. Comparison of 4-chloro-2-nitrophenol adsorption on single-walled and multi-walled carbon nanotubes

    Directory of Open Access Journals (Sweden)

    Mehrizad Ali

    2012-09-01

    Full Text Available Abstract The adsorption characteristics of 4-chloro-2-nitrophenol (4C2NP onto single-walled and multi-walled carbon nanotubes (SWCNTs and MWCNTs from aqueous solution were investigated with respect to the changes in the contact time, pH of solution, carbon nanotubes dosage and initial 4C2NP concentration. Experimental results showed that the adsorption efficiency of 4C2NP by carbon nanotubes (both of SWCNTs and MWCNTs increased with increasing the initial 4C2NP concentration. The maximum adsorption took place in the pH range of 2–6. The linear correlation coefficients of different isotherm models were obtained. Results revealed that the Langmuir isotherm fitted the experimental data better than the others and based on the Langmuir model equation, maximum adsorption capacity of 4C2NP onto SWCNTs and MWCNTs were 1.44 and 4.42 mg/g, respectively. The observed changes in the standard Gibbs free energy, standard enthalpy and standard entropy showed that the adsorption of 4C2NP onto SWCNTs and MWCNTs is spontaneous and exothermic in the temperature range of 298–328 K.

  11. Photodissociation dynamics of 2-chloro-6-nitrotoluene and nitrocyclopentane in gas phase: Laser-induced fluorescence detection of OH

    Energy Technology Data Exchange (ETDEWEB)

    Kawade, Monali N.; Saha, Ankur; Upadhyaya, Hari P.; Kumar, Awadhesh; Naik, Prakash D., E-mail: pdnaik@barc.gov.in

    2014-10-31

    Highlights: • Photodissociation studies on chloronitrotoluene (ClNT) and nitrocyclopentane (NCP). • Nascent OH product detected state selectively using laser induced fluorescence. • OH formation takes place from the ground electronic state with an exit barrier. • UV photodissociation dynamics of ClNT and NCP is different. - Abstract: Photodissociation of 2-chloro-6-nitrotoluene (ClNT) at 193, 248 and 266 nm and nitrocyclopentane (NCP) at 193 nm leads to the formation of OH, as detected by laser-induced fluorescence (LIF). The nascent OH produced from the photolysis of ClNT at all the wavelengths is vibrationally cold, with the Boltzmann type rotational state distributions. However, the nascent OH product from NCP is in the ground and vibrationally excited states with the measured average relative population in ν{sup ″}=1 to that in ν{sup ″}=0 of 0.12 ± 0.03, and these levels are characterized by rotational temperatures of 650 ± 180 K and 1570 ± 90 K, respectively. The translational energy partitioned in the OH fragment has been measured for photodissociation of both ClNT and NCP. On the basis of both the experimental results and the ground state molecular orbital (MO) calculations, a plausible mechanism for the OH formation has been proposed.

  12. Photodissociation dynamics of 2-chloro-6-nitrotoluene and nitrocyclopentane in gas phase: Laser-induced fluorescence detection of OH

    Science.gov (United States)

    Kawade, Monali N.; Saha, Ankur; Upadhyaya, Hari P.; Kumar, Awadhesh; Naik, Prakash D.

    2014-10-01

    Photodissociation of 2-chloro-6-nitrotoluene (ClNT) at 193, 248 and 266 nm and nitrocyclopentane (NCP) at 193 nm leads to the formation of OH, as detected by laser-induced fluorescence (LIF). The nascent OH produced from the photolysis of ClNT at all the wavelengths is vibrationally cold, with the Boltzmann type rotational state distributions. However, the nascent OH product from NCP is in the ground and vibrationally excited states with the measured average relative population in ν″ = 1 to that in ν″ = 0 of 0.12 ± 0.03, and these levels are characterized by rotational temperatures of 650 ± 180 K and 1570 ± 90 K, respectively. The translational energy partitioned in the OH fragment has been measured for photodissociation of both ClNT and NCP. On the basis of both the experimental results and the ground state molecular orbital (MO) calculations, a plausible mechanism for the OH formation has been proposed.

  13. Effects of Acupuncture on 1-chloro-2,4-dinitrochlorobenzene-induced Allergic Contact Dermatitis in Mice.

    Science.gov (United States)

    Chen, Cuicui; Liu, Xiaozhu; Li, Yinfeng; Liang, Huankun; Li, Kangyan; Li, Jiali; Cheng, Chengwu; Liu, Xianpan; Zhong, Shuhai; Li, Laiqing; Wang, Yan

    2017-08-01

    Allergic contact dermatitis (ACD) is a chronic inflammatory skin disease. Topical corticosteroids are the first-line therapy for ACD despite their significant adverse effects. Acupuncture has been widely used in the treatment of various skin diseases, but its underlying mechanism remains unrevealed. In this study, we investigated the characteristics of acupuncture treatment based on effectiveness and mechanism. BALB/c mice received 1-chloro-2,4-dinitrobenzene (DNCB) application to build AD-like model. Results showed that acupuncture was an effective treatment method in inhibiting inflammatory conditions, serum IgE levels, and expression of proinflammatory cytokine Th2 (IL-4, IL-6), and Th2 (IL-1β, TNF-α) mRNA compared with DNCB treatment. Acupuncture treatment also inhibited nuclear factor-κB p65, phosphorylation of IκBα, and phosphorylation of occludin proteins expression. Furthermore, it could improve the expression of epidermal growth factor in both mRNA and protein levels. These results suggest that acupuncture, as an alternative therapy treatment for its no significant side effects, was effective in alleviating ACD by reducing proinflammatory cytokines and changing proteins' expression. Copyright © 2017. Published by Elsevier B.V.

  14. A novel high sensitivity HPLC assay for topiramate, using 4-chloro-7-nitrobenzofurazan as pre-column fluorescence derivatizing agent.

    Science.gov (United States)

    Bahrami, Gholamreza; Mohammadi, Bahareh

    2007-05-01

    A new, sensitive and simple high-performance liquid chromatographic method for analysis of topiramate, an antiepileptic agent, using 4-chloro-7-nitrobenzofurazan as pre-column derivatization agent is described. Following liquid-liquid extraction of topiramate and an internal standard (amlodipine) from human serum, derivatization of the drugs was performed by the labeling agent in the presence of dichloromethane, methanol, acetonitrile and borate buffer (0.05 M; pH 10.6). A mixture of sodium phosphate buffer (0.05 M; pH 2.4): methanol (35:65 v/v) was eluted as mobile phase and chromatographic separation was achieved using a Shimpack CLC-C18 (150 x 4.6 mm) column. In this method the limit of quantification of 0.01 microg/mL was obtained and the procedure was validated over the concentration range of 0.01 to 12.8 microg/mL. No interferences were found from commonly co-administrated antiepileptic drugs including phenytoin, phenobarbital carbamazepine, lamotrigine, zonisamide, primidone, gabapentin, vigabatrin, and ethosuximide. The analysis performance was carried-out in terms of specificity, sensitivity, linearity, precision, accuracy and stability and the method was shown to be accurate, with intra-day and inter-day accuracy from -3.4 to 10% and precise, with intra-day and inter-day precision from 1.1 to 18%.

  15. Migration studies of 3-chloro-1,2-propanediol (3-MCPD) in polyethylene extrusion-coated paperboard food packaging.

    Science.gov (United States)

    Pace, Gregory V; Hartman, Thomas G

    2010-06-01

    The manufacturing process of paperboard food packaging can produce small quantities of 3-chloro-1,2-propanediol (3-MCPD or 3-monochloropropane-1,2-diol) when wet-strength resins containing epichlorohydrin are used. 3-MCPD is from the same family as 1,3-dichloro-2-propanol (1,3-DCP), which is known to cause cancer in animals. 3-MCPD has been found in acid hydrolyzed vegetable protein, Asian sauces and paperboard for food contact. In this investigation, we conducted extraction studies to measure 3-MCPD migration into food simulant solvents from the food contact side of polyethylene extrusion-coated paperboard beverage cartons and aqueous extractions of cut pieces from the entire paperboard. We demonstrate that 3-MCPD confirmed present at concentrations up to 9.9 mg kg(-1) within the paperboard matrix does not migrate through the polyethylene-coated food contact surface. The aqueous extraction of the entire paperboard and food contact side extractions with aqueous/acidic food simulants were performed using US Food and Drug Administration (FDA) and European Commission (EU) migration testing protocols. We also show that no significant amount of 3-MCPD migrates through the unskived edges on the inside seam of the paperboard structure. The methodology for the aqueous and migration cell extractions using GC-MS analyses was validated with a limit of quantification (LOQ) of 0.009 mg kg(-1) and a limit of detection (LOD) of 0.005 mg kg(-1).

  16. Development and application of 3-chloro-1,2-propandiol electrochemical sensor based on a polyaminothiophenol modified molecularly imprinted film.

    Science.gov (United States)

    Sun, Xiulan; Zhang, Lijuan; Zhang, Hongxia; Qian, He; Zhang, Yinzhi; Tang, Lili; Li, Zaijun

    2014-05-21

    In this work, a novel electrochemical sensor for 3-chloro-1,2-propandiol (3-MCPD) detection based on a gold nanoparticle-modified glassy carbon electrode (AuNP/GCE) coated with a molecular imprinted polymer (MIP) film was constructed. p-Aminothiophenol (p-ATP) and 3-MCPD were self-assembled on a AuNP/GCE surface, and then a MIP film was formed by electropolymerization. The 3-MCPD template combined with p-ATP during self-assembly and electropolymerization, and the cavities matching 3-MCPD remained after the removal of the template. The MIP sensor was characterized by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and scanning electron microscopy (SEM). Many factors that affected the performance of the MIP membrane were discussed and optimized. Under optimal conditions, the DPV current was linear with the log of the 3-MCPD concentration in the range from 1.0 × 10(-17) to 1.0 × 10(-13) mol L(-1) (R(2) = 0.9939), and the detection limit was 3.8 × 10(-18) mol L(-1) (S/N = 3). The average recovery rate of 3-MCPD from spiked soy sauce samples ranged from 95.0% to 106.4% (RSD 3-MCPD.

  17. Synthesis and in-vitro antibacterial activity of N-piperazinyl quinolone derivatives with 5-chloro-2-thienyl group

    Directory of Open Access Journals (Sweden)

    2008-08-01

    Full Text Available Background and the purpose of the study: Fluoroquinolones are an important group of antimicrobial agents that are used widely in the treatment of various infectious diseases. The purpose of the present study was to synthesize new N-piperazinyl quinolone derivatives with 5-chloro-2-theinyl group having possible antimicrobial activity. Methods: Reaction of ciprofloxacin (1, norfloxacin (2 and enoxacin (3 with α-bromoketone 10 or α-bromooxime derivatives 11a-c in DMF, in the presence of NaHCO3 at room temperature, afforded corresponding ketones 4a-c or oxime derivatives 5-7(a-c, respectively. Results and major conclusion: The synthesized compounds were tested against a series of Gram-positive and Gram-negative bacteria. The results of MIC tests against both Gram-positive and Gram-negative bacteria revealed that ciprofloxacin derivatives (compounds 4a, 5a, 6a and 7a were more active than norfloxacin and enoxacin analogues. Compound 5a, containing N-[2-(5-chlorothiophen-2-yl-2-hydroxyiminoethyl] residue provided a high in vitro antibacterial activity against Gram-positive bacteria, with MIC of 0.06, 0.125, 0.5 and 0.125 μg/mL against S. aureus, S. epidermidis, E. feacalis and B. subtilis, respectively. Its activity was found to be 4 to 8 times better than reference drug (ciprofloxacin against all Gram-positive bacteria with the exception of E. feacalis.

  18. 3,5-Bis(4-meth­oxy­phen­yl)-1-phenyl-4,5-dihydro-1H-pyrazole

    OpenAIRE

    Baktır, Zeliha; Akkurt, Mehmet; Samshuddin, S.; Narayana, B.; Yathirajan, H. S.

    2011-01-01

    In the title compound, C23H22N2O2, the central pyrazole ring is nearly planar (r.m.s. deviation = 0.046 Å) and it makes a dihedral angle of 18.5 (2)° with the phenyl ring. The dihedral angles between the phenyl and the two methoxy-substituted phenyl rings are 26.2 (2) and 80.6 (2)°. The crystal structure is stabilized by C—H...π stacking interactions and weak π–π interactions [cen...

  19. In Vivo Imaging of Xenograft Tumors Using an Epidermal Growth Factor Receptor-Specific Affibody Molecule Labeled with a Near-infrared Fluorophore

    Directory of Open Access Journals (Sweden)

    Haibiao Gong

    2010-02-01

    Full Text Available Overexpression of epidermal growth factor receptor (EGFR is associated with many types of cancers. It is of great interest to noninvasively image the EGFR expression in vivo. In this study, we labeled an EGFR-specific Affibody molecule (Eaff with a near-infrared (NIR dye IRDye800CW maleimide and tested the binding of this labeled molecule (Eaff800 in cell culture and xenograft mouse tumor models. Unlike EGF, Eaff did not activate the EGFR signaling pathway. Results showed that Eaff800 was bound and taken up specifically by EGFR-overexpressing A431 cells. When Eaff800 was intravenously injected into nude mice bearing A431 xenograft tumors, the tumor could be identified 1 hour after injection and it became most prominent after 1 day. Images of dissected tissue sections demonstrated that the accumulation of Eaff800 was highest in the liver, followed by the tumor and kidney. Moreover, in combination with a human EGFR type 2 (HER2-specific probe Haff682, Eaff800 could be used to distinguish between EGFR- and HER2-overexpressing tumors. Interestingly, the organ distribution pattern and the clearance rate of Eaff800 were different from those of Haff682. In conclusion, Eaff molecule labeled with a NIR fluorophore is a promising molecular imaging agent for EGFR-overexpressing tumors.

  20. Cranial nerve contrast using nerve-specific fluorophores improved by paired-agent imaging with indocyanine green as a control agent

    Science.gov (United States)

    Torres, Veronica C.; Vuong, Victoria D.; Wilson, Todd; Wewel, Joshua; Byrne, Richard W.; Tichauer, Kenneth M.

    2017-09-01

    Nerve preservation during surgery is critical because damage can result in significant morbidity. This remains a challenge especially for skull base surgeries where cranial nerves (CNs) are involved because visualization and access are particularly poor in that location. We present a paired-agent imaging method to enhance identification of CNs using nerve-specific fluorophores. Two myelin-targeting imaging agents were evaluated, Oxazine 4 and Rhodamine 800, and coadministered with a control agent, indocyanine green, either intravenously or topically in rats. Fluorescence imaging was performed on excised brains ex vivo, and nerve contrast was evaluated via paired-agent ratiometric data analysis. Although contrast was improved among all experimental groups using paired-agent imaging compared to conventional, solely targeted imaging, Oxazine 4 applied directly exhibited the greatest enhancement, with a minimum 3 times improvement in CNs delineation. This work highlights the importance of accounting for nonspecific signal of targeted agents, and demonstrates that paired-agent imaging is one method capable of doing so. Although staining, rinsing, and imaging protocols need to be optimized, these findings serve as a demonstration for the potential use of paired-agent imaging to improve contrast of CNs, and consequently, surgical outcome.

  1. Synthesis of 14C-labelled polychlorobiphenyls derived from the labelled 4-chloro-, 2,5-dichloro-, 3,4-dichloro-, 2,3-dichloro-2,4,5-trichloro- and 2,3,6-trichloroanilines

    International Nuclear Information System (INIS)

    Bergman, A.; Bamford, I.; Wachtmeister, C.A.

    1981-01-01

    [ 14 C]Aniline hydrogen sulphate was acetylated, and the acetanilide obtained was chlorinated with N-chlorosuccinimide to 2-chloro, 4-chloro- and 2,4-dichloroacet[ 14 C]anilide. The labelled 2- and 4-chloroacet[ 14 C]anilides were hydrolyzed and treated with aluminium chloride, hydrogen chloride and chlorine in dry dichloromethane to give the major products 2,5-dichloro-and 3,4-dichloro[ 14 C]aniline. The labelled 2,3-dichloro- and 2,3,6-trichloroanilines were obtained as minor products from the chlorination of 2-chloro[ 14 C]aniline, likewise 2,4,5-trichloroaniline was obtained from 4-chloro[ 14 C]aniline. The [ 14 C]anilines prepared were coupled with benzene, 1,4-dichloro-, 1,2-dichloro- or 1,3-dichlorobenzene to give 4-chloro-, 2,3',4',5-tetrachloro-, 2,3,3',4'-tetrachloro-, 3,3',4,4'-tetrachloro-, 2,2',5,5'-tetrachloro-, 2,2',3,3'-tetrachloro-, 2,2',3,5',6-pentachloro-, 2,2',4,4',5-pentachloro- and 2,3',4,5,5'-pentachloro[ 14 C]biphenyl. 3,4-Dichloro[ 14 C]aniline and biphenyls prepared from this aniline were found to be contaminated by bromoanalogues. The origin of these have been studied. (author)

  2. Crystal structures of two erbium(III complexes with 4-aminobenzoic acid and 4-chloro-3-nitrobenzoic acid

    Directory of Open Access Journals (Sweden)

    Graham Smith

    2015-12-01

    Full Text Available The crystal structures of two erbium(III complexes with 4-aminobenzoic acid (4-ABAH, namely bis(μ2-4-aminobenzoato-κ2O:O′bis[bis(4-aminobenzoato-κ2O,O′diaquaerbium(III] dihydrate, [Er2(C7H6NO26(H2O4]·2H2O, (I, and 4-chloro-3-nitrobenzoic acid (CLNBAH, namely poly[hexakis(μ2-4-chloro-3-nitrobenzoato-κ2O:O′bis(dimethyl sulfoxide-κOdierbium(III], [Er2(C7H3ClNO46(C2H6OS2]n, (II, have been determined. In the structure of solvatomorphic compound (I, the symmetry-related irregular ErO8 coordination polyhedra in the discrete centrosymmetric dinuclear complex comprise two monodentate water molecules and six carboxylate O-atom donors, four from two bidentate carboxylate O,O′-chelate groups and two from the bis-monodentate O:O′-bridging group of the third 4-ABA anion. The Er—O bond-length range is 2.232 (3–2.478 (3 Å and the Er...Er separation in the dinuclear complex unit is 4.7527 (4 Å. One of the coordinating water molecules is involved in an intra-unit O—H...O hydrogen-bonding association with an inversion-related carboxylate O-atom acceptor. In contrast, the anhydrous compound (II is polymeric, based on centrosymmetric dinuclear repeat units comprising ErO7 coordination polyhedra which involve four O-atom donors from two bidentate O:O′-bridging carboxylate groups, one O-atom donor from the monodentate dimethyl sulfoxide ligand and two O-atom donors from the third bridging CLNBA anion. The latter provides the inter-unit link in the one-dimensional coordination polymer extending along [100]. The Er—O bond-length range in (II is 2.239 (6–2.348 (6 Å and the Er...Er separation within the dinuclear unit is 4.4620 (6 Å. In the crystal of (I, extensive inter-dimer O—H...O and N—H...O hydrogen-bonding interactions involving both the coordinating water molecules and the solvent water molecules, as well as the amine groups of the 4-ABA anions, give an overall three-dimensional network structure. Within

  3. AT_CHLORO, a comprehensive chloroplast proteome database with subplastidial localization and curated information on envelope proteins.

    Science.gov (United States)

    Ferro, Myriam; Brugière, Sabine; Salvi, Daniel; Seigneurin-Berny, Daphné; Court, Magali; Moyet, Lucas; Ramus, Claire; Miras, Stéphane; Mellal, Mourad; Le Gall, Sophie; Kieffer-Jaquinod, Sylvie; Bruley, Christophe; Garin, Jérôme; Joyard, Jacques; Masselon, Christophe; Rolland, Norbert

    2010-06-01

    Recent advances in the proteomics field have allowed a series of high throughput experiments to be conducted on chloroplast samples, and the data are available in several public databases. However, the accurate localization of many chloroplast proteins often remains hypothetical. This is especially true for envelope proteins. We went a step further into the knowledge of the chloroplast proteome by focusing, in the same set of experiments, on the localization of proteins in the stroma, the thylakoids, and envelope membranes. LC-MS/MS-based analyses first allowed building the AT_CHLORO database (http://www.grenoble.prabi.fr/protehome/grenoble-plant-proteomics/), a comprehensive repertoire of the 1323 proteins, identified by 10,654 unique peptide sequences, present in highly purified chloroplasts and their subfractions prepared from Arabidopsis thaliana leaves. This database also provides extensive proteomics information (peptide sequences and molecular weight, chromatographic retention times, MS/MS spectra, and spectral count) for a unique chloroplast protein accurate mass and time tag database gathering identified peptides with their respective and precise analytical coordinates, molecular weight, and retention time. We assessed the partitioning of each protein in the three chloroplast compartments by using a semiquantitative proteomics approach (spectral count). These data together with an in-depth investigation of the literature were compiled to provide accurate subplastidial localization of previously known and newly identified proteins. A unique knowledge base containing extensive information on the proteins identified in envelope fractions was thus obtained, allowing new insights into this membrane system to be revealed. Altogether, the data we obtained provide unexpected information about plastidial or subplastidial localization of some proteins that were not suspected to be associated to this membrane system. The spectral counting-based strategy was further

  4. Synthesis of 3-(4, 5-dihydro-1-phenyl-5-substituted phenyl-1H-pyrazol-3-yl-2H-chromen-2-one derivatives and evaluation of their anticancer activity

    Directory of Open Access Journals (Sweden)

    Nitin Kumar

    2017-05-01

    Full Text Available A novel series of 3-(4, 5-dihydro-1-phenyl-5-substituted phenyl-1H-pyrazol-3-yl-2H-chromen-2-one derivatives were synthesized. In the first step salicylaldehyde was reacted with ethylacetoacetate at room temperature by stirring which gives compound (I. Compound (I when refluxed with substituted benzaldehyde and diethylamine in the presence of n-butanol for 4–5 h gives substituted derivatives (IIa–d. Compounds synthesized in step 2 when refluxed with phenyl hydrazine in the presence of pyridine for 6–7 h gives the title compounds (IIIa–d. All the synthesized compounds were sent to NCI for anticancer activity. Synthesized compounds were tested for anticancer activity against 60 different cell lines. From the data thus obtained it was observed that simple coumarin ring derivatives were more effective in inhibiting the growth of cancerous cell lines, than coumarin-pyrazoline derivatives. Among all the synthesized compounds, irrespective of compounds having simple coumarin ring and coumarin-pyrazoline combination, compounds IIa–c, IIIb and IIId were potent anticancer agents. Compounds were active for the single dose therapeutic program at the dose of 1.00E-5 molar concentration. The main anti cancer activity is assumed to be due to the presence of the lactone structure in coumarin moiety.

  5. Effect of symmetric substitution on the phenyl groups of Eu{sup 3+}-dibenzoyl methane complexes on their luminescence properties

    Energy Technology Data Exchange (ETDEWEB)

    Shukla, P. [Bio-Organic Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Sudarsan, V.; Vatsa, R.K. [Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Nayak, S.K. [Bio-Organic Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India); Chattopadhyay, S., E-mail: schatt@barc.gov.i [Bio-Organic Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)

    2010-10-15

    Complexes of Eu{sup 3+} ion and ligands like dibenzoylmethane (DBM) as well as flouro- and methoxy-substituted DBMs have been prepared and characterized. Peak maxima and line shapes of the {pi}-{pi}{sup *} transitions arising from the ligands in these complexes were very sensitive to the nature of the substituents attached to the phenyl groups of DBM. Symmetric substitution at both the phenyl groups led to improved luminescence in terms of higher quantum yields of emission and longer lifetime of the excited state ({sup 5}D{sub 0}) of Eu{sup 3+} ions. Effective averaging/cancellation of the dipole-dipole interactions in symmetrically substituted ligands and the associated decrease in the extent of quenching were responsible for the improved luminescence from such complexes.

  6. FORMULA ESTABLISHMENT OF COLORLESS Pb(II COMPLEX WITH N-BENZOYL-N-PHENYL HYDROXYLAMINE (BPA USING ATOMIC ABSORPTION SPECTROSCOPY

    Directory of Open Access Journals (Sweden)

    Dhananjay B Sarode

    2012-02-01

    Full Text Available A new method for determination of stoichiometry of colorless complexes by using atomic absorption spectrophotometric technique in continuous variation method and slope ratio method was described here. This method can be used in same manner as that of mole ratio method and slope ratio method. In this method atomic absorption spectroscopy was used instead of UV-Vis spectrophotometry. Atomic absorption spectrophotometric technique is superior to UV-Vis spectrophotometry as it can be applied to colorless soluble complexes. Pb(II and n-benzoyl-n-phenyl hydroxylamine react to form colorless complex at pH 6.5, which can be easily determined by this method. It was found that Pb(II forms 1:2 complex with n-benzoyl-n-phenyl hydroxylamine and is quantitatively extracted back to aqueous solution for AAS analysis.

  7. New Poly(amide-imide)/Nanocomposites Reinforced Silicate Nanoparticles Based on N-pyromellitimido-L-phenyl Alanine Containing Ether Moieties

    Science.gov (United States)

    Faghihi, Khalil; Shabanian, Meisam; Dadfar, Ehsan

    2012-02-01

    A series of Poly(amide-imide)/montmorillonite nanocomposites containing N-pyromellitimido-L-phenyl alanine moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide-imide) (PAI) 5 as a source of polymer matrix was synthesized by the direct polycondensation reaction of N-pyromellitimido-L-phenyl alanine 3 with 4,4'-diamino diphenyl ether 4 in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). The resulting nanocomposite films were characterized by Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The results showed that organo-modified clay was dispersed homogeneously in PAI matrix. TGA indicated an enhancement of thermal stability of new nanocomposites compared with the pure polymer.

  8. (1S,3S,4S-tert-Butyl N-[1-benzyl-3-hydroxy-5-phenyl-4-(picolinamidopentyl]carbamate

    Directory of Open Access Journals (Sweden)

    Jian-Feng Zheng

    2008-07-01

    Full Text Available The title compound, C29H35N3O4, was obtained by the reaction of (2S,4S,5S-tert-butyl N-(4-amino-1-benzyl-3-hydroxy-5-phenylpentylcarbamate and picolinic acid using oxalyl chloride as a chlorinating reagent to activate the carboxyl group. In the crystal structure there are two molecules in the asymmetric unit, which are aligned edge-to-face. In one molecule, the pyridyl ring forms a dihedral angle of 22.0 (1° with the phenyl ring of the terminal benzyl group and 14.3 (1° with the other phenyl ring; in the other molecule, the corresponding angles are 12.1 (1 and 10.6 (1°, respectively. The packing is stabilized by intermolecular hydrogen bonds and C—H...π interactions.

  9. Purification of di-nonyl phenyl phosphoric acid (DNPPA) for synergistic extraction of uranium from strong phosphoric acid

    International Nuclear Information System (INIS)

    Singh, D.K.; Vijayalakshmi, R.; Singh, H.; Sharma, J.N.; Ruhela, R.

    2009-01-01

    Di-nonyl phenyl phosphoric acid (DNPPA) obtained from various synthesis methods is always associated with impurities such as mono-nonyl phenyl phosphoric acid and nonyl phenol which need to be separated for its effective use in the extraction of uranium from strong phosphoric acid. Two methods of purification namely liquid-solid separation method using neodymium salt and liquid-liquid separation method using methylene glycol have been described. In the liquid solid separation method the purity of DNPPA obtained was about 95% with less than 1.0% monoester, however it heavily suffers in the recovery aspect which is of the order of 50-60%. The methylene glycol treatment method, results in high purity and recovery of the product. Purity obtained was about 95.0% diester and less than 0.5% monoester and recovery was more than 90%. Analysis of DNPPA was done by potentiometric titration method using autotitrator. (author)

  10. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine inhibits proton motive force in energized liver mitochondria

    International Nuclear Information System (INIS)

    Singh, Y.; Bhatnagar, R.; Sidhu, G.S.; Batra, J.K.; Krishna, G.

    1989-01-01

    It is known that 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), which induces Parkinson's-like disease in primates and humans, depletes hepatocytes of ATP and subsequently causes cell death. Incubation of rat liver mitochondria with MPTP and 1-methyl-4-phenyl pyridinium ion (MPP+) significantly inhibited incorporation of 32 Pi into ATP. MPTP and MPP+ inhibited the development of membrane potential and pH gradient in energized rat liver mitochondria, suggesting that reduction of the proton motive force may have reduced ATP synthesis. Since deprenyl, an inhibitor of monoamine oxidase, prevented the formation of MPP+ and inhibited the decrease in membrane potential caused by MPTP, but not that caused by MPP+, these effects of MPTP, as well as cell death, probably were mediated by MPP+. This mechanism may play a role in the specific loss of dopaminergic neurons resulting in MPTP-induced Parkinson's disease

  11. Crystal structure of 1-methoxy-5-methyl-N-phenyl-1,2,3-triazole-4-carboxamide

    Directory of Open Access Journals (Sweden)

    Inna S. Khazhieva

    2015-10-01

    Full Text Available The title compound, C11H12N4O2,was prepared via the transformation of sodium 4-acetyl-1-phenyl-1H-[1.2.3]triazolate under the action of methoxyamine hydrochloride. The dihedral angle between the triazole and phenyl rings is 25.12 (16° and the C atom of the methoxy group deviates from the triazole plane by 0.894 (4Å. The conformation of the CONHR-group is consolodated by an intramolecular N—H...N hydrogen bond to an N-atom of the triazole ring, which closes an S(5 ring. In the crystal, weak N—H...N hydrogen bonds link the molecules into C(6 [010] chains.

  12. The liquid-liquid extraction of chloro-(trichlorostannato)-rhodium(I/III) and -ruthenium (II) complexes from dilute hydrochloric acid into 4-methylpentan-2-one

    International Nuclear Information System (INIS)

    Wyrley-Birch, J.M.

    1984-10-01

    The effect of stannous chloride on the liquid-liquid extraction of rhodium and ruthenium from hydrochloric acid solutions into 4-methyl-pentan-2-one (MIBK)/hexane mixtures was studied in detail. Stannous chloride concentrations were found to considerably increase the efficiency of the extraction of rhodium and ruthenium into the organic phase. Chloro-(trichlorostannato)-rhodium (I/III) complexes were formed at room temperature. The rate of chloro-(trichlorostannato)-ruthenium (II) complex formation was extremely slow at room temperature, but increased on heating of the aqueous solutions. The amount of rhodium and ruthenium extracted into the organic phase depend on the Sn(II):M molar ratio, the HCl, H sup(+) and Cl sup(-) concentrations, as well as the equilibration time. A 119 Sn NMR study of the MIBK extracts, showed that the stoichiometry of the chloro-(trichlorostannato)-rhodium (I/III) complexes extracted into the organic phase was dependent on the Sn(II):Rh(III) molar ratio as well as the HCl, H sup(+) and Cl sup(-) concentrations in the aqueous phase. The predominant species observed in the organic phase from HCl solutions containing Sn(II):Rh(III) ratios >= 5:1, was shown to be an hydrido complex having the form [RhH(SnCl 3 ) 4 Cl] 3 sup(-) or [RhH(SnCl 3 ) 4 ]2 sup(-). An essentially quantitative separation of rhodium and ruthenium was achieved utilising the variation in the rates of rhodium-tin and ruthenium-tin complex formation

  13. Ruthenium(II carbonyl compounds with the 4′-chloro-2,2′:6′,2′′-terpyridine ligand

    Directory of Open Access Journals (Sweden)

    Rajendhraprasad Tatikonda

    2017-04-01

    Full Text Available Two ruthenium carbonyl complexes with the 4′-chloro-2,2′:6′,2′′-terpyridine ligand (tpy-Cl, C15H10ClN3, i.e. [RuCl(tpy-Cl(CO2][RuCl3(CO3] (I [systematic name: cis-dicarbonylchlorido(4′-chloro-2,2′:6′,2′′-terpyridine-κ3Nruthenium(II fac-tricarbonyltrichloridoruthenate(II], and [RuCl2(tpy-Cl(CO2] (II [cis-dicarbonyl-trans-dichlorido(4′-chloro-2,2′:6′,2′′-terpyridine-κ2N1,N1′ruthenium(II], were synthesized and characterized by single-crystal X-ray diffraction. The RuII atoms in both centrosymmetric structures (I and (II display similar, slightly distorted octahedral coordination spheres. The coordination sphere in the complex cation in compound (I is defined by three N atoms of the tridentate tpy-Cl ligand, two carbonyl carbon atoms and one chlorido ligand; the charge is balanced by an octahedral [Ru(CO3Cl3]− counter-anion. In the neutral compound (II, the tpy-Cl ligand coordinates to the metal only through two of its N atoms. The coordination sphere of the RuII atom is completed by two carbonyl and two chlorido ligands. In the crystal structures of both (I and (II, weak C—H...Cl interactions are observed.

  14. 2?Diazo?1?phenyl?2?((trifluoromethyl)sulfonyl)ethan?1?one: Another Utility for Electrophilic Trifluoromethylthiolation Reactions

    OpenAIRE

    Huang, Zhongyan; Okuyama, Kenta; Wang, Chen; Tokunaga, Etsuko; Li, Xiaorui; Shibata, Norio

    2016-01-01

    Abstract 2?Diazo?1?phenyl?2?((trifluoromethyl)sulfonyl)ethan?1?one (diazo?triflone) (2) is not only a building block but also a reagent. In this study, diazo?triflone, which was originally used for the synthesis of ??lactam triflones as a trifluoromethanesulfonyl (SO2CF3) building block under catalyst?free thermal conditions, is redisclosed as an effective electrophilic trifluoromethylthiolation reagent under copper catalysis. A broad set of enamines, indoles, ??keto esters, pyrroles, and ani...

  15. Synthesis and Herbicidal Activity of 5-Heterocycloxy-3-substituted-1-(3-trifluoromethyl)phenyl-1H-pyrazole

    Institute of Scientific and Technical Information of China (English)

    XU Han; HU Xu-hong; ZOU Xiao-mao; ZHU You-quan; LIU Bin; HU Fang-zhong; YANG Hua-zheng

    2012-01-01

    The authors synthesized a series of novel 5-heterocycloxy-3-substituted-1-(3-trifluoromethyl)phenyl-1H- pyrazole derivatives.Herbicidal activities of the two intermediate compounds and thirteen target compounds were evaluated via Brassica napus and Echinochloa crusgalli(L.) Beauv tests.Bioassay results show that some of the compounds exhibit better inhibiting activities against Brassica napus and some of the compounds exhibit bleaching activities against Echinochloa crusgalli(L.) Beauv at 100 μg/mL.

  16. (3R,6S,7aS-3-Phenyl-6-(phenylsulfanylperhydropyrrolo[1,2-c]oxazol-5-one

    Directory of Open Access Journals (Sweden)

    Anthony D. Woolhouse

    2009-05-01

    Full Text Available Molecules of the title compound [systematic name: (2R,5S,7S-2-phenyl-7-phenylsulfanyl-1-aza-3-oxabicyclo[3.3.0]octan-8-one], C18H17NO2S, form high quality crystals even though they are only packed using C—H...O(carbonyl and weak C—H...S interactions. The dihedral angle between the aromatic rings is 85.53 (5°. The fused rings adopt envelope and twist conformations.

  17. 4-Allyl-6-bromo-2-phenyl-4H-imidazo[4,5-b]pyridine monohydrate

    Directory of Open Access Journals (Sweden)

    Younès Ouzidan

    2010-08-01

    Full Text Available In the molecule of the title compound, C15H12BrN3·H2O, the phenyl ring is coplanar with the imidazopyridine ring system [dihedral angle = 0.4 (1°]. The water molecule is disordered over two positions with occupancies of 0.58 (1 and 0.42 (1, and it is linked to the main molecule via an O—H...N hydrogen bond.

  18. 3-Phenyl-6-(2-pyrid­yl)-1,2,4,5-tetra­zine

    OpenAIRE

    Chartrand, Daniel; Laverdière, François; Hanan, Garry

    2007-01-01

    The title compound, C13H9N5, is the first asymmetric diaryl-1,2,4,5-tetrazine to be crystallographically characterized. We have been interested in this motif for incorporation into supramolecular assemblies based on coordination chemistry. The solid state structure shows a centrosymmetric molecule, forcing a positional disorder of the terminal phenyl and pyridyl rings. The molecule is completely planar, unusual for aromatic rings with N atoms in adjacent ortho positions. The stacking observed...

  19. 2-Chloro-2,2-difluoroacetophenone: a non-ODS-based difluorocarbene precursor and its use in the difluoromethylation of phenol derivatives.

    Science.gov (United States)

    Zhang, Laijun; Zheng, Ji; Hu, Jinbo

    2006-12-22

    A novel and non-ODS-based (ODS = ozone-depleting substance) preparation of 2-chloro-2,2-difluoroacetophenone (1) was achieved in high yield by using 2,2,2-trifluoroacetophenone as the starting material. Compound 1 was found to act as a good difluorocarbene reagent, which readily reacts with a variety of structurally diverse phenol derivatives 4 in the presence of potassium hydroxide or potassium carbonate to produce aryl difluoromethyl ethers 5 in good yields. This new and easy-to-handle synthetic methodology offers an environmentally friendly alternative to other Freon- or Halon-based difluoromethylating approaches.

  20. Synthesis and Conformational Assignment of N-(E-Stilbenyloxymethylenecarbonyl-Substituted Hydrazones of Acetone and o-(m- and p- Chloro- (nitro- benzaldehydes by Means of and NMR Spectroscopy

    Directory of Open Access Journals (Sweden)

    Przemysław Patorski

    2013-01-01

    Full Text Available Eighteen new N-(E-stilbenyloxyalkylcarbonyl-substituted hydrazones of ortho- (meta- and para- chloro- (nitro- benzaldehydes 1–18 and two analogous hydrazones of acetone 19-20 were prepared. The stereochemical behavior of 1–18 in dimethyl-d6 sulfoxide solution has been studied by NMR and NMR techniques, using spectral data of 19 and 20 as supporting material. The E-geometrical isomers and cis-/trans-amide conformers have been found for these hydrazones. Energy barriers of isomers are reported.

  1. Synthesis of Highly Branched Polyolefins Using Phenyl Substituted α-Diimine Ni(II Catalysts

    Directory of Open Access Journals (Sweden)

    Fuzhou Wang

    2016-04-01

    Full Text Available A series of α-diimine Ni(II complexes containing bulky phenyl groups, [ArN = C(NaphthC = NAr]NiBr2 (Naphth: 1,8-naphthdiyl, Ar = 2,6-Me2-4-PhC6H2 (C1; Ar = 2,4-Me2-6-PhC6H2 (C2; Ar = 2-Me-4,6-Ph2C6H2 (C3; Ar = 4-Me-2,6-Ph2C6H2 (C4; Ar = 4-Me-2-PhC6H3 (C5; Ar = 2,4,6-Ph3C6H2 (C6, were synthesized and characterized. Upon activation with either diethylaluminum chloride (Et2AlCl or modified methylaluminoxane (MMAO, all Ni(II complexes showed high activities in ethylene polymerization and produced highly branched amorphous polyethylene (up to 145 branches/1000 carbons. Interestingly, the sec-butyl branches were observed in polyethylene depending on polymerization temperature. Polymerization of 1-alkene (1-hexene, 1-octene, 1-decene and 1-hexadecene with C1-MMAO at room temperature resulted in branched polyolefins with narrow Mw/Mn values (ca. 1.2, which suggested a living polymerization. The polymerization results indicated the possibility of precise microstructure control, depending on the polymerization temperature and types of monomers.

  2. Negative polarity of phenyl-C61 butyric acid methyl ester adjacent to donor macromolecule domains

    International Nuclear Information System (INIS)

    Alley, Olivia J.; Dawidczyk, Thomas J.; Hardigree, Josué F. Martínez; Katz, Howard E.; Wu, Meng-Yin; Johns, Gary L.; Markovic, Nina; Arnold, Michael S.

    2015-01-01

    Interfacial fields within organic photovoltaics influence the movement of free charge carriers, including exciton dissociation and recombination. Open circuit voltage (V oc ) can also be dependent on the interfacial fields, in the event that they modulate the energy gap between donor HOMO and acceptor LUMO. A rise in the vacuum level of the acceptor will increase the gap and the V oc , which can be beneficial for device efficiency. Here, we measure the interfacial potential differences at donor-acceptor junctions using Scanning Kelvin Probe Microscopy, and quantify how much of the potential difference originates from physical contact between the donor and acceptor. We see a statistically significant and pervasive negative polarity on the phenyl-C 61 butyric acid methyl ester (PCBM) side of PCBM/donor junctions, which should also be present at the complex interfaces in bulk heterojunctions. This potential difference may originate from molecular dipoles, interfacial interactions with donor materials, and/or equilibrium charge transfer due to the higher work function and electron affinity of PCBM. We show that the contact between PCBM and poly(3-hexylthiophene) doubles the interfacial potential difference, a statistically significant difference. Control experiments determined that this potential difference was not due to charges trapped in the underlying substrate. The direction of the observed potential difference would lead to increased V oc , but would also pose a barrier to electrons being injected into the PCBM and make recombination more favorable. Our method may allow unique information to be obtained in new donor-acceptor junctions

  3. 2-Acetylpyridine N4-Phenyl- Thiosemicarbazone as a new tool for tumour diagnosis

    International Nuclear Information System (INIS)

    Soares, Marcella Araugio; Pesquero, Jorge Luiz

    2009-01-01

    The aim of this work was to determine in vivo biodistribution of radiolabelled 2-acetylpyridine N4 phenyl thiosemicarbazone (Ph) and to evaluate its applicability for tumour diagnosis. Ph was labelled with 125 I using lactoperoxidase method and radiochemical analysis was performed by chromatography. 125 I-Ph production was successful with 86 ± 9.2% of radiochemical purity and high specific activity (17.6 TBq /mmol). 125 I-Ph was used for biodistribution and pharmacokinetics studies on Swiss mice bearing Ehrlich solid tumour. 125 I-Ph presented a rapid blood clearance (T 1/2 = 97.2 min.) and the kidneys were the main excretion pathway (CL0.01 mL/min). 125 I-Ph uptake was significant in tumour (2.5%ID/g) and tumour-to-normal tissue uptake was more than 20-fold higher depending on the organ. The uptake by the organs like heart, lungs, stomach and liver followed the blood perfusion. Our results suggest that 125 I-Ph possess indispensable characteristics for an efficient radiopharmaceutical for tumour diagnosis. The next step will be to evaluate the quality of tumour SPECT images provided by 131 I-Ph. (author)

  4. Methyl 6-methoxycarbonylmethyl-2-oxo-4-phenyl-1,2,3,4-tetrahydropyrimidine-5-carboxylate

    Directory of Open Access Journals (Sweden)

    Lucia Veizerová

    2008-09-01

    Full Text Available The title compound, C15H16N2O5, belongs to the class of monastrol-type anti-cancer agents and was selected for crystal structure determination in order to determine the conformational details needed for subsequent structure–activity relationship studies. The central tetrahydropyrimidine ring has a flat-envelope conformation. The 4-phenyl group occupies a pseudo-axial position and is inclined at an angle of ca 90° to the mean plane of the heterocyclic ring. Of the two methyl ester groups, one (in the 5-position is in a coplanar and the other (in the 6-position in a perpendicular orientation with respect to the heterocyclic plane. The coplanar 5-ester group has its carbonyl bond oriented cis with respect to the pyrimidine C=C double bond. By comparison of the structural results for the present compound with those determined previously for its diethyl analogue, we have identified the molecular factors which control the dual course of the Biginelli reaction with salicylaldehyde. The crystal structure is dominated by two hydrogen bonds which link the molecules into chains of dimers.

  5. Mitochondria targeted peptides protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine neurotoxicity.

    Science.gov (United States)

    Yang, Lichuan; Zhao, Kesheng; Calingasan, Noel Y; Luo, Guoxiong; Szeto, Hazel H; Beal, M Flint

    2009-09-01

    A large body of evidence suggests that mitochondrial dysfunction and oxidative damage play a role in the pathogenesis of Parkinson's disease (PD). A number of antioxidants have been effective in animal models of PD. We have developed a family of mitochondria-targeted peptides that can protect against mitochondrial swelling and apoptosis (SS peptides). In this study, we examined the ability of two peptides, SS-31 and SS-20, to protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) neurotoxicity in mice. SS-31 produced dose-dependent complete protection against loss of dopamine and its metabolites in striatum, as well as loss of tyrosine hydroxylase immunoreactive neurons in substantia nigra pars compacta. SS-20, which does not possess intrinsic ability in scavenging reactive oxygen species, also demonstrated significant neuroprotective effects on dopaminergic neurons of MPTP-treated mice. Both SS-31 and SS-20 were very potent (nM) in preventing MPP+ (1-methyl-4-phenylpyridinium)-induced cell death in cultured dopamine cells (SN4741). Studies with isolated mitochondria showed that both SS-31 and SS-20 prevented MPP+-induced inhibition of oxygen consumption and ATP production, and mitochondrial swelling. These findings provide strong evidence that these neuroprotective peptides, which target both mitochondrial dysfunction and oxidative damage, are a promising approach for the treatment of PD.

  6. Synthesis and Application of Phenyl Nitrone Derivatives as Acidic and Microbial Corrosion Inhibitors

    Directory of Open Access Journals (Sweden)

    Shijun Chen

    2015-01-01

    Full Text Available Nitrone has drawn great attention due to its wide applications as a 1,3-dipole in heterocyclic compounds synthesis and the bioactivities. With the special structure, nitrone can also be used as ligand in inorganic chemistry. Based on the current research, the nitrones are anticipated to be effective inhibitors against acidic and microbial corrosion. The aim of this work is to investigate the inhibitory action of nitrones. In this work, a series of phenyl nitrone derivatives (PN was synthesized and used as acidic and microbial corrosion inhibitors. The results indicate that several compounds show moderate to high inhibition efficiency (IE in 3% HCl. Accompanied with HMTA or BOZ, the IEs greatly increase, and the highest efficiency of 98.5% was obtained by using PN4 + BOZ. Investigation of the antibacterial activity against oilfield microorganism shows that the nitrone derivatives can inhibit SRB, IB, and TGB with moderate to high efficiency under 1,000 mg/L, which makes them potential to be used as bifunctional oilfield chemicals.

  7. Synthesis and characterisation of new Schiff base monomers containing N-(alkyl and phenyl) pyrrole moieties

    Science.gov (United States)

    Amer, Ahcene Ait; Ilikti, Hocine; Maschke, Ulrich

    2017-11-01

    This article deals with the synthesis and characterisation of seven new functional Schiff base monomers, such as: M1: 1-(3-Pyrrole-1-yl-propylimino-methyl)-naphtalen-2-ol; M2: 2-(3-Pyrrole-1-yl-phenylimino-methyl)-phenol; M3: 1-(3-Pyrrole-1-yl-phenylimino-methyl)-naphtalen-2-ol; M4: N-(pyridin-2-yl-methylene)-2-(pyrrol-1-yl)-benzenamine; M5: N-(pyridin-2-yl-methylene)-3-(pyrrol-1-yl)-propan-1-amine; M6: 2-(3-pyrrol-1-yl-propylimino-methyl)-quinolin-8-ol; M7: 2-(3-pyrrol-1-yl-phenylimino-methyl)-quinolin-8-ol. Two series of compounds emerged from this study, N-propyl pyrrole derivatives (M1, M5, M6) and N-phenyl pyrrole compounds (M2, M3, M4, M7). All monomers were elaborated by condensation reactions between appropriate amines and aldehydes, and their molecular structures were confirmed by spectroscopic analysis methods like FT-IR, 1H NMR, 13C NMR, and GC-MS.

  8. Synthesis of [3-14C]- and [phenyl-U-14C] olaquindox

    International Nuclear Information System (INIS)

    Maul, W.; Scherling, D.; Seng, F.

    1981-01-01

    Olaquindox is a new feed additive. [ 14 C]Olaquindox, labelled in different positions, was needed for tracer-studies of pharmacokinetics, biotransformation and residues in several species of animals. 2-[N-(2-hydroxethyl)-carbamoyl]-3-methyl-[3- 14 C]quinoxaline-1,4-dioxide([3- 14 C]Olaquindox) was synthesized from barium[ 14 C]carbonate (22 mmoles; 1.15 Ci) via [1- 14 C]acetic acid, sodium[1- 14 C]acetate, [1- 14 C]acetylchloride, ethyl[3- 14 C]acetoacetate and 2-carbethoxy-3-methyl-[3- 14 C]quinoxaline-1,4-dioxide with an overall yield of 10%, based on barium[ 14 C]carbonate. The radiochemical purity was better than 98% (tlc). The specific activities of three preparations were 10.5, 8.4 and 5.45 μCi/mg respectively. [phenyl-U- 14 C]Olaquindox was synthesized starting from [U- 14 C]aniline (19.8 mmoles; 284.4 mCi). Intermediate products were N-acetyl[U- 14 C]aniline, 2-nitro-N-acetyl[U- 14 C]aniline, 2-nitro[U- 14 C]aniline and [U- 14 C]benzofurazanoxide. The total yield was 50% as calculated for [U- 14 C]aniline. At calibration samples of two preparations showed specific activities of 49.5 and 11.1 μCi/mg respectively. The radiochemical purity was checked by tlc and exceeded 98%. (author)

  9. Inactivation of acetylcholinesterase by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine hydrochloride.

    Science.gov (United States)

    Zang, Lun-Yi; Misra, Hara P

    2003-12-01

    The neurotoxicant 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) has been shown to reversibly inhibit the activity of acetylcholinesterase. The inactivation of the enzyme was detected by monitoring the accumulation of yellow color produced from the reaction between thiocholine and dithiobisnitrobenzoate ion. The kinetic parameter, Km for the substrate (acetylthiocholine), was found to be 0.216 mM and Ki for MPTP inactivation of acetylcholinesterase was found to be 2.14 mM. The inactivation of enzyme by MPTP was found to be dose-dependent. It was found that MPTP is neither a substrate of AChE nor the time-dependent inactivator. The studies of reaction kinetics indicate the inactivation of AChE to be a linear mixed-type inhibition. The dilution assays indicate that MPTP is a reversible inhibitor for AChE. These data suggest that once MPTP enters the basal ganglia of the brain, it can inactivate the acetylcholinesterase enzyme and thereby increase the acetylcholine level in the basal ganglia of brain, leading to potential cell dysfunction. It appears that the nigrostriatal toxicity by MPTP leading to Parkinson's disease-like syndrome may, in part, be mediated via the acetylcholinesterase inactivation.

  10. Mechanisms of catalytic cleavage of benzyl phenyl ether in aqueous and apolar phases

    Energy Technology Data Exchange (ETDEWEB)

    He, Jiayue; Lu, Lu; Zhao, Chen; Mei, Donghai; Lercher, Johannes A.

    2014-03-01

    Catalytic pathways for the cleavage of ether bonds in benzyl phenyl ether (BPE) in liquid phase using Ni- and zeolite-based catalysts are explored. In the absence of catalysts, the C-O bond is selectively cleaved in water by hydrolysis, forming phenol and benzyl alcohol as intermediates, followed by alkylation. The hydronium ions catalyzing the reactions are provided by the dissociation of water at 523 K. Upon addition of HZSM-5, rates of hydrolysis and alkylation are markedly increased in relation to proton concentrations. In the presence of Ni/SiO2, the selective hydrogenolysis dominates for cleaving the Caliphatic-O bond. Catalyzed by the dual-functional Ni/HZSM-5, hydrogenolysis occurs as the major route rather than hydrolysis (minor route). In apolar undecane, the non-catalytic thermal pyrolysis route dominates. Hydrogenolysis of BPE appears to be the major reaction pathway in undecane in the presence of Ni/SiO2 or Ni/HZSM-5, almost completely suppressing radical reactions. Density functional theory (DFT) calculations strongly support the proposed C-O bond cleavage mechanisms on BPE in aqueous and apolar phases. These calculations show that BPE is initially protonated and subsequently hydrolyzed in the aqueous phase. Finally, DFT calculations suggest that the radical reactions in non-polar solvents lead to primary benzyl and phenoxy radicals in undecane, which leads to heavier condensation products as long as metals are absent for providing dissociated hydrogen.

  11. 2-Acetylpyridine N4-Phenyl- Thiosemicarbazone as a new tool for tumour diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Marcella Araugio; Pesquero, Jorge Luiz [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Fisiologia e Biofisica], e-mail: marcellaaraugio@yahoo.com.br; Costa, Pryscila R. da; Mendes, Isolda M.C.; Beraldo, Heloisa; Santos, Raquel Gouvea dos [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)], e-mail: santosr@cdtn.br

    2009-07-01

    The aim of this work was to determine in vivo biodistribution of radiolabelled 2-acetylpyridine N4 phenyl thiosemicarbazone (Ph) and to evaluate its applicability for tumour diagnosis. Ph was labelled with {sup 125}I using lactoperoxidase method and radiochemical analysis was performed by chromatography. {sup 125}I-Ph production was successful with 86 {+-} 9.2% of radiochemical purity and high specific activity (17.6 TBq /mmol). {sup 125}I-Ph was used for biodistribution and pharmacokinetics studies on Swiss mice bearing Ehrlich solid tumour. {sup 125}I-Ph presented a rapid blood clearance (T{sub 1/2}= 97.2 min.) and the kidneys were the main excretion pathway (CL0.01 mL/min). {sup 125}I-Ph uptake was significant in tumour (2.5%ID/g) and tumour-to-normal tissue uptake was more than 20-fold higher depending on the organ. The uptake by the organs like heart, lungs, stomach and liver followed the blood perfusion. Our results suggest that {sup 125}I-Ph possess indispensable characteristics for an efficient radiopharmaceutical for tumour diagnosis. The next step will be to evaluate the quality of tumour SPECT images provided by {sup 131}I-Ph. (author)

  12. KINETICS AND MECHANISM OF PHOTOINDUCED POLYMERIZATION BY α,α-DIMETHOXY-α-PHENYL ACETOPHENONE

    Institute of Scientific and Technical Information of China (English)

    WANG Xiuzhi; LI Miaozhen; CHANG Zhiying; WANG Erjian

    1993-01-01

    α,α- dimethoxy- α-phenyl acetophenone (DMPA) is an efficient and thermally stable photoinitiator.Here its spectral characteristics in the transient state were shown. The transient species were identified as a benzoyl radical and a dimethoxyl benzyl radical that played a primary initiation role in polymerization. The kinetics and mechanism of the bulk polymerization of MMA were investigated. The exponent of DMPA concentration and κp/κt1/2 value were found to be 0.5 and 0.066 mol-1/2l1/2 s-1/2 , respectively. The existence of oxygen led to obtain the polymer with higher molecular weight, which can be attributed to the occurrence of the subsequent polymerization induced by active polymer end group. In the photocrosslinking reaction, the dependence of DMPA content on initial rate has been found. A principal reason is that the sample contained higher percentage of DMPA has higher light-absorbed efficiency. In solid film, higher concentration of DMPA is permitted to be used because there is little excited state self-quenching effect in the rigid medium.

  13. A theoretical and shock tube kinetic study on hydrogen abstraction from phenyl formate.

    Science.gov (United States)

    Ning, Hongbo; Liu, Dapeng; Wu, Junjun; Ma, Liuhao; Ren, Wei; Farooq, Aamir

    2018-06-12

    The hydrogen abstraction reactions of phenyl formate (PF) by different radicals (H/O(3P)/OH/HO2) were theoretically investigated. We calculated the reaction energetics for PF + H/O/OH using the composite method ROCBS-QB3//M06-2X/cc-pVTZ and that for PF + HO2 at the M06-2X/cc-pVTZ level of theory. The high-pressure limit rate constants were calculated using the transition state theory in conjunction with the 1-D hindered rotor approximation and tunneling correction. Three-parameter Arrhenius expressions of rate constants were provided over the temperature range of 500-2000 K. To validate the theoretical calculations, the overall rate constants of PF + OH → Products were measured in shock tube experiments at 968-1128 K and 1.16-1.25 atm using OH laser absorption. The predicted overall rate constants agree well with the shock tube data (within 15%) over the entire experimental conditions. Rate constant analysis indicates that the H-abstraction at the formic acid site dominates the PF consumption, whereas the contribution of H-abstractions at the aromatic ring increases with temperature. Additionally, comparisons of site-specific H-abstractions from PF with methyl formate, ethyl formate, benzene, and toluene were performed to understand the effects of the aromatic ring and side-chain substituent on H-abstraction rate constants.

  14. Synthesis and molecular modelling studies of phenyl linked oxadiazole-phenylhydrazone hybrids as potent antileishmanial agents.

    Science.gov (United States)

    Taha, Muhammad; Ismail, Nor Hadiani; Imran, Syahrul; Anouar, El Hassane; Selvaraj, Manikandan; Jamil, Waqas; Ali, Muhammad; Kashif, Syed Muhammad; Rahim, Fazal; Khan, Khalid Mohammed; Adenan, Mohd Ilham

    2017-01-27

    Molecular hybridization yielded phenyl linked oxadiazole-benzohydrazones hybrids 6-35 and were evaluated for their antileishmanial potentials. Compound 10, a 3,4-dihydroxy analog with IC 50 value of 0.95 ± 0.01 μM, was found to be the most potent antileishmanial agent (7 times more active) than the standard drug pentamidine (IC 50  = 7.02 ± 0.09 μM). The current series 6-35 conceded in the identification of thirteen (13) potent antileishmanial compounds with the IC 50 values ranging between 0.95 ± 0.01-78.6 ± 1.78 μM. Molecular docking analysis against pteridine reductase (PTR1) were also performed to probe the mode of action. Selectivity index showed that compounds with higher number of hydroxyl groups have low selectivity index. Theoretical stereochemical assignment was also done for certain derivatives by using density functional calculations. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  15. Electrical and photoelectrical properties of poly(phenyl azomethine furane) thin films devices

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, G.D. [J.N.V. Univ., Jodhpur (India). Dept. of Phys.; Sandogaker, S.G. [J.N.V. Univ., Jodhpur (India). Dept. of Phys.; Roy, M.S. [Camouflage Division, Defence Laboratory, Jodhpur (Raj.) (India)

    1996-05-15

    Poly(phenyl azomethine furane) (PPAF), a conjugated system of poly-Schiff base was synthesised by condensation of p-aminobenzene with furane-2-aldehyde. Oxidative polymerization was conducted at 0-5 C temperature, and the polymer formed was found to be soluble in common organic solvent. Optical properties were studied in the UV-visible-IR region. Electrical and photoelectrical properties of Al/PPAF/ITO and Ag/PPAF/ITO sandwich devices were investigated by measuring the steady state photocurrent resulting from illumination. The device Al/PPAF/ITO shows a Schottky barrier at the Al-PPAF interface and ohmic contact at ITO-PPAF interface. The device Ag/PPAF/ITO shows ohmic contact at both interfaces. This behaviour has been explained in terms of P-type conductivity of the PPAF and the formation of a Schottky barrier with the low work function electrode and ohmic contact with the higher work function electrode. Under low forward bias voltage (ITO positive) ohmic conduction is observed while at higher voltage there is space charge-limited conduction (SCLC). The dependence of the photo short-circuit current on illumination intensity was discussed in detail. The C-V characteristics of both devices have also been analysed. (orig.)

  16. Synthesis, characterization and corrosion inhibition efficiency of N-(4-(Morpholinomethyl Carbamoyl Phenyl Furan-2-Carboxamide

    Directory of Open Access Journals (Sweden)

    N. Zulfareen

    2016-01-01

    Full Text Available A mannich base namely N-(4-(Morpholinomethyl Carbamoyl Phenyl Furan-2-Carboxamide (MFC was synthesized and characterized by FT-IR, 1H NMR, and 13C NMR. The molecular weight of MFC was confirmed by LC-MS. The inhibition effect of MFC on brass in 1 M HCl medium has been investigated by weight loss measurement, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS and cyclic voltametry (CV. Thermodynamic parameters such as free energy, entropy and enthalpy were calculated to describe the mechanism of corrosion inhibitor. The inhibition efficiency of MFC increases with increase in concentration and temperature ranges from 30 °C to 60 °C. Polarization measurements indicated that MFC acts as a mixed type corrosion inhibitor. AC impedance indicates that Rct value increases with increase in the concentration of inhibitor. CV reveals that the oxidation of the copper is controlled by the addition of inhibitor on the brass metal. Surface analysis using scanning electron microscope (SEM shows a significant morphological improvement on the brass surface with the addition of the inhibitor. The adsorption of MFC on brass obeys Langmuir adsorption isotherm. The molecular structure of MFC was distorted to quantum chemical indices using density functional theory (DFT which indicates that the inhibition efficiency of MFC is closely related to quantum parameters.

  17. Entry of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine into the rat brain

    International Nuclear Information System (INIS)

    Riachi, N.J.; LaManna, J.C.; Harik, S.I.

    1989-01-01

    We studied blood-to-brain entry of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), 1-methyl-4-phenylpyridinium (MPP+) and butanol in anesthetized rats using the indicator-fractionation method with right atrial bolus injection. Minimal amounts of MPP+, which has low octanol/water partition coefficient, crossed the blood-brain barrier. MPTP and butanol, both of which have high octanol/water partition coefficients, were almost completely extracted by all regions of the brain on the first pass. The main difference between the MPTP and butanol tracers is that butanol rapidly left the brain with an exponential rate constant of 1.24 min-1, whereas MPTP was avidly retained by the brain with a washout rate constant of 0.10 min-1 (mean values for the four brain regions that we studied). Early retention of MPTP by the brain was not due to its rapid metabolism by monoamine oxidase because pargyline pretreatment did not affect this rate constant. However, 30 min after [ 3 H]MPTP injection, brain retention of the 3H tracer was reduced significantly by pargyline treatment, and the ratio of brain MPTP/MPP+ was increased markedly

  18. A novel single fluorophore-labeled double-stranded oligonucleotide probe for fluorescence-enhanced nucleic acid detection based on the inherent quenching ability of deoxyguanosine bases and competitive strand-displacement reaction.

    Science.gov (United States)

    Zhang, Yingwei; Tian, Jingqi; Li, Hailong; Wang, Lei; Sun, Xuping

    2012-01-01

    We develop a novel single fluorophore-labeled double-stranded oligonucleotide (OND) probe for rapid, nanostructure-free, fluorescence-enhanced nucleic acid detection for the first time. We further demonstrate such probe is able to well discriminate single-base mutation in nucleic acid. The design takes advantage of an inherent quenching ability of guanine bases. The short strand of the probe is designed with an end-labeled fluorophore that is placed adjacent to two guanines as the quencher located on the long opposite strand, resulting in great quenching of dye fluorescence. In the presence of a target complementary to the long strand of the probe, a competitive strand-displacement reaction occurs and the long strand forms a more stable duplex with the target, resulting in the two strands of the probe being separated from each other. As a consequence of this displacement, the fluorophore and the quencher are no longer in close proximity and dye fluorescence increases, signaling the presence of target.

  19. Electrochemical and Spin-Trapping Properties of para-substituted α-Phenyl-N-tert-butyl Nitrones

    International Nuclear Information System (INIS)

    Rosselin, Marie; Tuccio, Béatrice; Pério, Pierre; Villamena, Frederick A.; Fabre, Paul-Louis; Durand, Grégory

    2016-01-01

    Nitrones are known both as therapeutic antioxidants and efficient spin-traps. In this work, the redox behavior of various para-substituted α-phenyl-N-tert-butyl nitrones (PBN) was studied by cyclic voltammetry. The polar effect of the substituents was found to correlate with the electrochemical properties of the nitronyl function. Compounds bearing an electron-withdrawing group were more easily reduced than those having an electron-donating group and an opposite trend was observed for the oxidation. Ease of oxidation was also computationally rationalized using DFT approach showing increased ease of oxidation with electron donating functionalities. Since electrochemical properties of nitrones are known to correlate with biological properties, this work provides insights in the design of potent nitrone antioxidants. Using cyclic voltammetry the relative rate of superoxide trapping by nitrones was investigated and compared to the classical antioxidant BHT. The determination of the relative rate of phenyl radical trapping was also carried out but showed no clear correlation with the nature of the substituents. This indicates the absence of a polar effect in agreement with previous data and further supports the intermediate nature, that is, non- or weakly nucleophile, of phenyl radical. On the contrary kinetics of hydroxymethyl radical trapping was found to correlate with the nature of the substituents, demonstrating the nucleophilic nature of its addition onto nitrones.

  20. Synthesis, studies and in-vitro antibacterial activity of N-substituted 5-(furan-2-yl-phenyl pyrazolines

    Directory of Open Access Journals (Sweden)

    Mamta Rani

    2015-03-01

    Full Text Available Novel compounds with antibacterial properties: pyrazoline derivatives were synthesized by the cyclization of various -1-[2-(alkoxyphenyl]-3-(furan-2-yl prop-2-en-1-one 1a–1d with N-substituted phenyl hydrazine in the presence of CH3COOH in ethanol. The structures of these compounds were elucidated by, IR, 1H NMR, 13C NMR, ESI-MS spectral data and their purities were confirmed by elemental analyses. The in vitro antibacterial activity of these compounds was evaluated against two Gram-positive and two Gram-negative bacteria Aeromonas hydrophila, Yersinia enterocolitica, Listeria monocytogenes, and Staphylococcus aureus by microdilution method and then the minimum inhibitory concentration (MIC of compounds were determined. The results showed that compounds (5R-5-(furan-2-yl-1-phenyl-3-[2-(benzyloxyphenyl]-4, 5-dihydro-1H-pyrazole (2b and (5R-5-(furan-2-yl-1-phenyl-3-[2-(naphthalen-2-ylmethoxy prop-2-en-1-yloxyphenyl]-4,5-dihydro-1H-pyrazole (2d showing most promising antibacterial activities as compared to Gentamicin and Tetracycline are given.

  1. Synthesis of 2-iodo- and 2-phenyl-[11C]melatonin: potential PET tracers for melatonin binding sites

    International Nuclear Information System (INIS)

    Chen Jiajun; Fiehn-Schulze, Brita; Firnau, Guenter; Brough, Paul A.; Snieckus, Victor

    1998-01-01

    Two 11 C-labelled melatonin derivatives, 2-iodo-[ 11 C]melatonin (2-iodo-5-methoxy-N[ 11 C-acetyl]-tryptamine, an agonist) and 2-phenyl-[ 11 C]melatonin (2-phenyl-5-methoxy-N[ 11 C-acetyl]tryptamine, a putative antagonist) were synthesized from [ 11 C]carbon dioxide. The reaction sequence was common to both compounds and consisted of three steps: (i) carbonylation of methyl magnesium bromide with [ 11 C]carbon dioxide, (ii) conversion of the adduct to [ 11 C]acetyl chloride, (iii) acetylation of the amine precursors (2-iodo-5-methoxy-tryptamine or 2-phenyl-5-methoxy-tryptamine) with [ 11 C]acetyl chloride. The precursors were especially prepared. The radiochemical yield was 19% for 2-iodomelatonin and 32% for 2-phenymelatonin, based on [ 11 C]carbon dioxide; the specific activity ranged from 300 to 600 mCi/μmol. Both labelled 2-substituted-melatonins are intended to be used as radiotracers to study melatonin binding sites in man with positron emission tomography

  2. Synthesis and Antiplasmodial Activity of 2-(4-Methoxyphenyl-4-Phenyl-1,10-Phenanthroline Derivative Compounds

    Directory of Open Access Journals (Sweden)

    Nazudin

    2012-08-01

    Full Text Available A unique of synthetic methods was employed to prepare 2-(4-methoxyphenyl-4-phenyl-1,10-phenanthroline (5 derivatives from 4-methoxy-benzaldehyde (1, acetophenone (2, and 8-aminoquinoline (4 with aldol condensation and cyclization reactions. The derivatives were tested through antiplasmodial test. The synthesis of derivatives compound 5 was conducted in three steps. The 3-(4-methoxyphenyl-1-phenylpropenone 3 was synthesized through aldol condensation of 1 and 2 which has a yield of 96.42%. The compound 5 was synthesized through cyclization of compound 4 and 3 with 84.55% yield. The derivative of compound 5 was synthesized from compound 5 using DMS and DES reagents which refluxed for 21 and 22 h, to produce (1-N-methyl-9-(4-methoxyphenyl-7-phenyl-1,10-phenanthrolinium sulfate (6 and (1-N-ethyl-9-(4-methoxyphenyl-7-phenyl-1,10-phenanthrolinium sulfate (7 with 91.42 and 86.36% yields, respectively. Results of in vitro testing of antiplasmodial activity of compound 5 derivatives (i.e., compound 6 and 7 against chloroquine-resistant P. falciparum FCR3 strain showed that compound 7 had higher antimalarial activity than compounds 5 and 6. Whereas, results of in vitro testing against chloroquine-sensitive P. falciparum D10 strain showed that compound 6 has higher antimalarial activity than compounds 5 and 7.

  3. Sleep-inducing N-alkyl-5-[m-(trifluoromethyl)phenyl]-5-hydroxy-2-pyrrolidinones and N-alkyl-3-(trifluoromethyl)cinnamamides.

    Science.gov (United States)

    Houlihan, W J; Gogerty, J H; Ryan, E A; Schmitt, G

    1985-01-01

    A series of N-alkyl-3-[m-(trifluoromethyl)phenyl]-5-hydroxy-2-pyrrolidinones and N-alkyl-3-(trifluoromethyl)-cinnamamides were prepared and screened in a series of tests designed to detect potential sleep inducers. The more active members of the series were evaluated for their ability to induce sleep in Cebus monkeys. The most active compound, N-methyl-5-[m-(trifluoromethyl)phenyl]-5-hydroxy-2-pyrrolidinone, was equal to methaqualone.

  4. 1,1′-{1,4-Phenylene bis[3-(6-chloro-2-methyl-4-phenylquinolin-3-yl-4,5-dihydro-1H-pyrazole-5,1-diyl]}dibutan-1-one

    Directory of Open Access Journals (Sweden)

    Allaoua Kedjadja

    2015-10-01

    Full Text Available A new polycyclic compound, 1,1′-{1,4-phenylene bis[3-(6-chloro-2-methyl-4-phenylquinolin-3-yl-4,5-dihydro-1H-pyrazole-5,1-diyl]}dibutan-1-one (3 has been synthesized by cyclocondensation of (2E,2′E-1,1′-bis(6-chloro-2-methyl-4-phenylquinolin-3-yl-3,3′-(1,4-phenylenediprop-2-en-1-one (2 and hydrazine hydrate in butanoic acid. The structure of this compound was established by elemental analysis, 1H-NMR, 13C-NMR, mass and IR spectroscopy.

  5. Design of peptide substrates for nanosecond time-resolved fluorescence assays of proteases: 2,3-diazabicyclo[2.2.2]oct-2-ene as a noninvasive fluorophore.

    Science.gov (United States)

    Hennig, Andreas; Florea, Mara; Roth, Doris; Enderle, Thilo; Nau, Werner M

    2007-01-15

    Fluorescence protease assays were investigated with peptide substrates containing a 2,3-diazabicyclo[2.2.2]oct-2-ene-labeled asparagine (Dbo) as a fluorescent amino acid. The special characteristic of the fluorophore Dbo is its exceedingly long fluorescence lifetime (ca. 300 ns in water under air), which allows the use of nanosecond time-resolved fluorescence (Nano-TRF) detection to efficiently suppress shorter-lived background emission. In addition, the natural amino acids tryptophan and tyrosine can be employed as intramolecular fluorescence quenchers, which facilitates substrate design. Fourteen synthetic peptide substrates (composed of 2-19 amino acids) and five enzymes (trypsin, pepsin, carboxypeptidase A, leucine aminopeptidase, and chymotrypsin) were investigated and, in all 28 examined combinations, enzymatic activity was detected by monitoring the increase in steady state fluorescence with time and determining the reaction rates as kcat/Km values, which ranged from 0.2 to 80x10(6) M-1 min-1. The results suggest an excellent compatibility of the very small and hydrophilic fluorescent probe Dbo with solid-phase peptide synthesis and the investigated proteases. For all 14 peptides the fluorescence lifetimes before and after enzymatic cleavage were measured and Nano-TRF measurements were performed in 384-well microplates. The fluorescence lifetimes of the different peptides provide the basis for the rational design of Dbo-based fluorescent substrates for protease assays. Measurements in Nano-TRF mode revealed, in addition to efficient suppression of background fluorescence, an increased differentiation between cleaved and uncleaved substrate. The Dbo-based assays can be adapted for high-throughput screening.

  6. Directed Evolution of Carbonyl Reductase from Rhodosporidium toruloides and Its Application in Stereoselective Synthesis of tert-Butyl (3R,5S)-6-Chloro-3,5-dihydroxyhexanoate.

    Science.gov (United States)

    Liu, Zhi-Qiang; Wu, Lin; Zhang, Xiao-Jian; Xue, Ya-Ping; Zheng, Yu-Guo

    2017-05-10

    tert-Butyl (3R,5S)-6-chloro-3,5-dihydroxyhexanoate ((3R,5S)-CDHH) is a key intermediate of atorvastatin and rosuvastatin synthesis. Carbonyl reductase RtSCR9 from Rhodosporidium toruloides exhibited excellent activity toward tert-butyl (S)-6-chloro-5-hydroxy-3-oxohexanoate ((S)-CHOH). For the activity of RtSCR9 to be improved, random mutagenesis and site-saturation mutagenesis were performed. Three positive mutants were obtained (mut-Gln95Asp, mut-Ile144Lys, and mut-Phe156Gln). These mutants exhibited 1.94-, 3.03-, and 1.61-fold and 1.93-, 3.15-, and 1.97-fold improvement in the specific activity and k cat /K m , respectively. Asymmetric reduction of (S)-CHOH by mut-Ile144Lys coupled with glucose dehydrogenase was conducted. The yield and enantiomeric excess of (3R,5S)-CDHH reached 98 and 99%, respectively, after 8 h bioconversion in a single batch reaction with 1 M (S)-CHOH, and the space-time yield reached 542.83 mmol L -1 h -1 g -1 wet cell weight. This study presents a new carbonyl reductase for efficient synthesis of (3R,5S)-CDHH.

  7. Biosynthesis of tert-butyl (3R,5S)-6-chloro-3,5-dihydroxyhexanoate by carbonyl reductase from Rhodosporidium toruloides in mono and biphasic media.

    Science.gov (United States)

    Liu, Zhi-Qiang; Wu, Lin; Zheng, Ling; Wang, Wen-Zhong; Zhang, Xiao-Jian; Jin, Li-Qun; Zheng, Yu-Guo

    2018-02-01

    tert-Butyl (3R,5S)-6-chloro-3,5-dihydroxyhexanoate ((3R,5S)-CDHH) is the key intermediate for synthesis of atorvastatin and rosuvastatin. Carbonyl reductase exhibits excellent activity toward tert-butyl (S)-6-chloro-5-hydroxy-3-oxohexanoate ((S)-CHOH) to synthesize (3R,5S)-CDHH. In this study, a whole cell biosynthesis reaction system to produce (3R,5S)-CDHH was constructed in organic solvents. A solution of 10% (v/v) Tween-80 was introduced to the reaction system as a co-solvent, which greatly enhanced biotransformation process, giving 98.9% yield, >99% ee and 1.8-fold higher space time yield in 5 h bioconversion of 1 M (S)-CHOH, compared with 98.7% yield and >99% ee in 9 h bioconversion of a purely aqueous reaction system. Moreover, a water-octanol biphasic reaction system was built and 20% of octanol was added as reservoir of substrate resulting in 98% yield, >99% ee and 4.08 mmol L -1  h -1  g -1 (wet cell weight) space time yield. This study paved a way for the whole cell biosynthesis of (3R,5S)-CDHH in mono and biphasic media. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Determination by high resolution liquid chromatography of 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside (Xgal) and intermediates of its synthesis

    International Nuclear Information System (INIS)

    Fernandez Villalobo, Anais; Nuevas Paz, Lauro; Rodriguez Dominguez, Juan C

    2010-01-01

    In microbiology, microorganisms markers have been found to be useful in the quality control of different products such as water and food, in which the presence of coliforms, especially E. coli has been identified. Several methods for detection and quantification of enterobacteria have been developed by using chromogenic substrates. Among them, indole derivatives such as 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside (Xgal), have come out. This indole derivative is widely employed as a constituent of microbiological diagnostic media because in the presence of coliforms (β-galactosidase producers), it forms a blue-indigo color. In this paper, the development and the validation, of an HPLC method for the quality control of Xgal in the presence of its intermediates obtained in each step of the synthesis is reported. These compounds were separated by using a RP-18 column and gradient elution with a mobile phase consisting of triethylammonium phosphate solution at pH 3(A) and acetonitrile (B). The detection and quantitation limits of the method was between 0.2- 0.5 % and 1.0 - 2.0 % respectively, which is acceptable if we consider that Xgal is not used as a drug. The proposed method is simple, selective, linear, precise and accurate and it can be used for the quality control of each of the intermediates and the final product, 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside

  9. One Pot Selective Arylation of 2-Bromo-5-Chloro Thiophene; Molecular Structure Investigation via Density Functional Theory (DFT), X-ray Analysis, and Their Biological Activities.

    Science.gov (United States)

    Rasool, Nasir; Kanwal, Aqsa; Rasheed, Tehmina; Ain, Quratulain; Mahmood, Tariq; Ayub, Khurshid; Zubair, Muhammad; Khan, Khalid Mohammed; Arshad, Muhammad Nadeem; M Asiri, Abdullah; Zia-Ul-Haq, Muhammad; Jaafar, Hawa Z E

    2016-06-28

    Synthesis of 2,5-bisarylthiophenes was accomplished by sequential Suzuki cross coupling reaction of 2-bromo-5-chloro thiophenes. Density functional theory (DFT) studies were carried out at the B3LYP/6-31G(d, p) level of theory to compare the geometric parameters of 2,5-bisarylthiophenes with those from X-ray diffraction results. The synthesized compounds are screened for in vitro bacteria scavenging abilities. At the concentration of 50 and 100 μg/mL, compounds 2b, 2c, 2d, 3c, and 3f with IC50-values of 51.4, 52.10, 58.0, 56.2, and 56.5 μg/mL respectively, were found most potent against E. coli. Among all the synthesized compounds 2a, 2d, 3c, and 3e with the least values of IC50 77, 76.26, 79.13 μg/mL respectively showed significant antioxidant activities. Almost all of the compounds showed good antibacterial activity against Escherichia coli, whereas 2-chloro-5-(4-methoxyphenyl) thiophene (2b) was found most active among all synthesized compound with an IC50 value of 51.4 μg/mL. All of the synthesized compounds were screened for nitric oxide scavenging activity as well. Frontier molecular orbitals (FMOs) and molecular electrostatic potentials of the target compounds were also studied theoretically to account for their relative reactivity.

  10. 2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine (ADAM): an improved serotonin transporter ligand

    Energy Technology Data Exchange (ETDEWEB)

    Oya, Shunichi; Choi, S.-R.; Hou, Catherine; Mu Mu; Kung, M.-P.; Acton, Paul D.; Siciliano, Michael; Kung, Hank F. E-mail: kunghf@sunmac.spect.upenn.edu

    2000-04-01

    Serotonin transporters (SERT) are target-sites for commonly used antidepressants, such as fluoxetine, paroxetine, sertraline, and so on. Imaging of these sites in the living human brain may provide an important tool to evaluate the mechanisms of action as well as to monitor the treatment of depressed patients. Synthesis and characterization of an improved SERT imaging agent, ADAM (2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine)(7) was achieved. The new compound, ADAM(7), displayed an extremely potent binding affinity toward SERT (K{sub i}=0.013 nM, in membrane preparations of LLC-PK{sub 1}-cloned cell lines expressing the specific monoamine transporter). ADAM(7) also showed more than 1,000-fold selectivity for SERT over norepinephrine transporter (NET) and dopamine transporter (DAT) (K{sub i}=699 and 840 nM, for NET and DAT, respectively). The radiolabeled compound [{sup 125}I]ADAM(7) showed an excellent brain uptake in rats (1.41% dose at 2 min post intravenous [IV] injection), and consistently displayed the highest uptake (between 60-240 min post IV injection) in hypothalamus, a region with the highest density of SERT. The specific uptake of [{sup 125}I]ADAM(7) in the hypothalamus exhibited the highest target-to-nontarget ratio ([hypothalamus - cerebellum]/cerebellum was 3.97 at 120 min post IV injection). The preliminary imaging study of [{sup 123}I]ADAM in the brain of a baboon by single photon emission computed tomography (SPECT) at 180-240 min post IV injection indicated a specific uptake in midbrain region rich in SERT. These data suggest that the new ligand [{sup 123}I]ADAM(7) may be useful for SPECT imaging of SERT binding sites in the human brain.

  11. 2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine (ADAM): an improved serotonin transporter ligand

    International Nuclear Information System (INIS)

    Oya, Shunichi; Choi, S.-R.; Hou, Catherine; Mu Mu; Kung, M.-P.; Acton, Paul D.; Siciliano, Michael; Kung, Hank F.

    2000-01-01

    Serotonin transporters (SERT) are target-sites for commonly used antidepressants, such as fluoxetine, paroxetine, sertraline, and so on. Imaging of these sites in the living human brain may provide an important tool to evaluate the mechanisms of action as well as to monitor the treatment of depressed patients. Synthesis and characterization of an improved SERT imaging agent, ADAM (2-((2-((dimethylamino)methyl)phenyl)thio)-5-iodophenylamine)(7) was achieved. The new compound, ADAM(7), displayed an extremely potent binding affinity toward SERT (K i =0.013 nM, in membrane preparations of LLC-PK 1 -cloned cell lines expressing the specific monoamine transporter). ADAM(7) also showed more than 1,000-fold selectivity for SERT over norepinephrine transporter (NET) and dopamine transporter (DAT) (K i =699 and 840 nM, for NET and DAT, respectively). The radiolabeled compound [ 125 I]ADAM(7) showed an excellent brain uptake in rats (1.41% dose at 2 min post intravenous [IV] injection), and consistently displayed the highest uptake (between 60-240 min post IV injection) in hypothalamus, a region with the highest density of SERT. The specific uptake of [ 125 I]ADAM(7) in the hypothalamus exhibited the highest target-to-nontarget ratio ([hypothalamus - cerebellum]/cerebellum was 3.97 at 120 min post IV injection). The preliminary imaging study of [ 123 I]ADAM in the brain of a baboon by single photon emission computed tomography (SPECT) at 180-240 min post IV injection indicated a specific uptake in midbrain region rich in SERT. These data suggest that the new ligand [ 123 I]ADAM(7) may be useful for SPECT imaging of SERT binding sites in the human brain

  12. Dimethyl phenyl piperazine iodide (DMPP) induces glioma regression by inhibiting angiogenesis

    Energy Technology Data Exchange (ETDEWEB)

    He, Yan-qing; Li, Yan; Wang, Xiao-yu [Key Laboratory for Regenerative Medicine of the Ministry of Education, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632 (China); He, Xiao-dong [Institute of Vascular Biological Sciences, Guangdong Pharmaceutical University, Guangzhou 510006 (China); Jun, Li [Guangdong Provincial Key Laboratory of Bioengineering Medicine, National Engineering Research Centre of Genetic Medicine, College of Life Science and Technology, Jinan University, Guangzhou 510632 (China); Chuai, Manli [Division of Cell and Developmental Biology, University of Dundee, Dundee, DD1 5EH (United Kingdom); Lee, Kenneth Ka Ho [Key Laboratory for Regenerative Medicine of the Ministry of Education, School of Biomedical Sciences, Chinese University of Hong Kong, Shatin (Hong Kong); Wang, Ju [Guangdong Provincial Key Laboratory of Bioengineering Medicine, National Engineering Research Centre of Genetic Medicine, College of Life Science and Technology, Jinan University, Guangzhou 510632 (China); Wang, Li-jing, E-mail: wanglijing62@163.com [Institute of Vascular Biological Sciences, Guangdong Pharmaceutical University, Guangzhou 510006 (China); Yang, Xuesong, E-mail: yang_xuesong@126.com [Key Laboratory for Regenerative Medicine of the Ministry of Education, Division of Histology and Embryology, Medical College, Jinan University, Guangzhou 510632 (China)

    2014-01-15

    1,1-Dimethyl-4-phenyl piperazine iodide (DMPP) is a synthetic nicotinic acetylcholine receptor (nAChR) agonist that could reduce airway inflammation. In this study, we demonstrated that DMPP could dramatically inhibit glioma size maintained on the chick embryonic chorioallantoic membrane (CAM). We first performed MTT and BrdU incorporation experiments on U87 glioma cells in vitro to understand the mechanism involved. We established that DMPP did not significantly affect U87 cell proliferation and survival. We speculated that DMPP directly caused the tumor to regress by affecting the vasculature in and around the implanted tumor on our chick CAM model. Hence, we conducted detailed analysis of DMPP's inhibitory effects on angiogenesis. Three vasculogenesis and angiogenesis in vivo models were used in the study which included (1) early chick blood islands formation, (2) chick yolk-sac membrane (YSW) and (3) CAM models. The results revealed that DMPP directly suppressed all developmental stages involved in vasculogenesis and angiogenesis – possibly by acting through Ang-1 and HIF-2α signaling. In sum, our results show that DMPP could induce glioma regression grown on CAM by inhibiting vasculogenesis and angiogenesis. - Highlights: ●We demonstrated that DMPP inhibited the growth of glioma cells on chick CAM. ●DMPP did not significantly affect the proliferation and survival of U87 cells. ●We revealed that DMPP suppressed vasculogenesis and angiogenesis in chick embryo. ●Angiogenesis in chick CAM was inhibited by DMPP via most probably Ang-1 and HIF-2α. ●DMPP could be potentially developed as an anti-tumor drug in the future.

  13. Phenyl vs Alkyl Polythiophene: A Solar Cell Comparison Using a Vinazene Derivative as Acceptor

    KAUST Repository

    Woo, Claire H.; Holcombe, Thomas W.; Unruh, David A.; Sellinger, Alan; Fréchet, Jean M. J.

    2010-01-01

    The solar cell performance of poly[3-(4-n-octyl)-phenylthiophene] (POPT) and poly(3hexylthiophene) (P3HT) are compared in devices using 4,7-bis(2-(l-(2-ethylhexyl)-4,5-dicyanoimidazol-2-yl)vinyi)benzo[c][l,2,5] -thiadiazole (EV-BT) as the electron acceptor. Despite their reduced light absorption, POPT:EV-BT devices generate higher photocurrents in both bilayer and bulk heterojunction (BHJ) architectures than analogous P3HT:EV-BT devices. Optimized POPT:EV-BT BHJ devices achieve 1.4% average efficiency, whereas the analogous P3HT devices only reach 1.1%. Morphology does not account for the large difference in performance as AFM studies of the active layer suggest, comparable levels of phase separation in the two systems. Reverse bias analysis demonstrates that P3HT devices have a higher maximum potential than POPT devices, but P3HT devices appear to be more severely limited by recombination losses under standard operating conditions. A possible explanation for the superior performance in POPT devices is that the pendant phenyl ring in POPT can twist out-of-plane and increase the separation distance with the acceptor molecule. A larger donor/acceptor separation distance can destabilize the geminate pair and lead to more efficient charge separation in POPT:EV-BT devices. Our results emphasize the importance of donor/acceptor pair interactions and its effect on charge separation, processes in polymer solar cells. © 2010 American Chemical Society.

  14. Studies on the Synthesis, Photophysical and Biological Evaluation of Some Unsymmetrical Meso-Tetrasubstituted Phenyl Porphyrins

    Directory of Open Access Journals (Sweden)

    Rica Boscencu

    2017-10-01

    Full Text Available Abstract: We designed three unsymmetrical meso-tetrasubstituted phenyl porphyrins for further development as theranostic agents for cancer photodynamic therapy (PDT: 5-(4-hydroxy-3-methoxyphenyl-10,15,20-tris-(4-acetoxy-3-methoxyphenylporphyrin (P2.2, Zn(II-5-(4-hydroxy-3-methoxyphenyl-10,15,20-tris-(4-acetoxy-3-methoxyphenylporphyrin (Zn(II2.2 and Cu(II-5-(4-hydroxy-3-methoxyphenyl-10,15,20-tris-(4-acetoxy-3-methoxyphenylporphyrin (Cu(II2.2. The porphyrinic compounds were synthesized and their structures were confirmed by elemental analysis, FT-IR, UV-Vis, EPR and NMR. The compounds had a good solubility in polar/nonpolar media. P2.2 and, to a lesser extent, Zn(II2.2 were fluorescent, albeit with low fluoresence quantum yields. P2.2 and Zn(II2.2 exhibited PDT-acceptable values of singlet oxygen generation. A “dark” cytotoxicity study was performed using cells that are relevant for the tumor niche (HT-29 colon carcinoma cells and L929 fibroblasts and for blood (peripheral mononuclear cells. Cellular uptake of fluorescent compounds, cell viability/proliferation and death were evaluated. P2.2 was highlighted as a promising theranostic agent for PDT in solid tumors considering that P2.2 generated PDT-acceptable singlet oxygen yields, accumulated into tumor cells and less in blood cells, exhibited good fluorescence within cells for imagistic detection, and had no significant cytotoxicity in vitro against tumor and normal cells. Complexing of P2.2 with Zn(II or Cu(II altered several of its PDT-relevant properties. These are consistent arguments for further developing P2.2 in animal models of solid tumors for in vivo PDT.

  15. Dimethyl phenyl piperazine iodide (DMPP) induces glioma regression by inhibiting angiogenesis

    International Nuclear Information System (INIS)

    He, Yan-qing; Li, Yan; Wang, Xiao-yu; He, Xiao-dong; Jun, Li; Chuai, Manli; Lee, Kenneth Ka Ho; Wang, Ju; Wang, Li-jing; Yang, Xuesong

    2014-01-01

    1,1-Dimethyl-4-phenyl piperazine iodide (DMPP) is a synthetic nicotinic acetylcholine receptor (nAChR) agonist that could reduce airway inflammation. In this study, we demonstrated that DMPP could dramatically inhibit glioma size maintained on the chick embryonic chorioallantoic membrane (CAM). We first performed MTT and BrdU incorporation experiments on U87 glioma cells in vitro to understand the mechanism involved. We established that DMPP did not significantly affect U87 cell proliferation and survival. We speculated that DMPP directly caused the tumor to regress by affecting the vasculature in and around the implanted tumor on our chick CAM model. Hence, we conducted detailed analysis of DMPP's inhibitory effects on angiogenesis. Three vasculogenesis and angiogenesis in vivo models were used in the study which included (1) early chick blood islands formation, (2) chick yolk-sac membrane (YSW) and (3) CAM models. The results revealed that DMPP directly suppressed all developmental stages involved in vasculogenesis and angiogenesis – possibly by acting through Ang-1 and HIF-2α signaling. In sum, our results show that DMPP could induce glioma regression grown on CAM by inhibiting vasculogenesis and angiogenesis. - Highlights: ●We demonstrated that DMPP inhibited the growth of glioma cells on chick CAM. ●DMPP did not significantly affect the proliferation and survival of U87 cells. ●We revealed that DMPP suppressed vasculogenesis and angiogenesis in chick embryo. ●Angiogenesis in chick CAM was inhibited by DMPP via most probably Ang-1 and HIF-2α. ●DMPP could be potentially developed as an anti-tumor drug in the future

  16. Comparative effects of 4-phenyl-3-butenoic acid and vorinostat on cell growth and signaling.

    Science.gov (United States)

    Burns, Timothy J; Ali, Amna; Matesic, Diane F

    2015-02-01

    4-phenyl-3-butenoic acid (PBA) is a small-molecule anti-inflammatory agent, which has been shown to inhibit growth, increase gap junction intercellular communication and modulate activation of p38 mitogen-activated protein kinase (p38 MAPK) and c-jun n-terminal kinase (JNK) in tumorigenic cells at concentrations that do not similarly affect non-tumorigenic cells. Vorinostat is an anticancer agent structurally similar to PBA. The purpose of this study was to compare the effects of these two agents on JNK and p38 activation, cell growth and gap junction intercellular communication (GJIC). Cell growth, GJIC and western blot analyses were performed utilizing tumorigenic WBras1 and H2009 human carcinoma cells, and non-tumorigenic WBneo3 and human bronchial epithelial (HBE) cells. Both compounds significantly inhibited WBras1 and H2009 tumorigenic cell growth and increased GJIC in WBras1 cells, as previously reported for PBA. Under similar conditions, both compounds increased phosphorylation of p38 MAPK in tumorigenic but not in non-tumorigenic cells and decreased phosphorylation of JNK in tumorigenic cells. However, a decrease in phosphorylation of JNK occurred in non-tumorigenic WBras1 cells following vorinostat treatment but not PBA treatment. Both compounds showed a selective growth inhibition of H2009 human carcinoma over normal HBE lung cells but, unlike PBA, vorinostat significantly decreased cell growth in WBneo3 cells. Overall, PBA exhibited similar effects to vorinostat in tumorigenic cells, while also showing reduced effects on JNK phosphorylation and growth in non-tumorigenic cells compared to ras-transformed cells. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  17. Phenyl vs Alkyl Polythiophene: A Solar Cell Comparison Using a Vinazene Derivative as Acceptor

    KAUST Repository

    Woo, Claire H.

    2010-03-09

    The solar cell performance of poly[3-(4-n-octyl)-phenylthiophene] (POPT) and poly(3hexylthiophene) (P3HT) are compared in devices using 4,7-bis(2-(l-(2-ethylhexyl)-4,5-dicyanoimidazol-2-yl)vinyi)benzo[c][l,2,5] -thiadiazole (EV-BT) as the electron acceptor. Despite their reduced light absorption, POPT:EV-BT devices generate higher photocurrents in both bilayer and bulk heterojunction (BHJ) architectures than analogous P3HT:EV-BT devices. Optimized POPT:EV-BT BHJ devices achieve 1.4% average efficiency, whereas the analogous P3HT devices only reach 1.1%. Morphology does not account for the large difference in performance as AFM studies of the active layer suggest, comparable levels of phase separation in the two systems. Reverse bias analysis demonstrates that P3HT devices have a higher maximum potential than POPT devices, but P3HT devices appear to be more severely limited by recombination losses under standard operating conditions. A possible explanation for the superior performance in POPT devices is that the pendant phenyl ring in POPT can twist out-of-plane and increase the separation distance with the acceptor molecule. A larger donor/acceptor separation distance can destabilize the geminate pair and lead to more efficient charge separation in POPT:EV-BT devices. Our results emphasize the importance of donor/acceptor pair interactions and its effect on charge separation, processes in polymer solar cells. © 2010 American Chemical Society.

  18. Spectral investigations, DFT based global reactivity descriptors, Inhibition efficiency and analysis of 5-chloro-2-nitroanisole as π-spacer with donor-acceptor variations effect for DSSCs performance

    Science.gov (United States)

    Meenakshi, R.

    2017-01-01

    FTIR, FT-Raman, UV, NMR and quantum chemical calculation studies are performed on 5-chloro-2-nitroanisole, in order to gain the insights of its structural, spectroscopic and electronic properties (Fukui indices, HOMO and LUMO energy gap, MESP and Global reactivity descriptors). A complete vibrational analysis of 5-chloro-2-nitroanisole is performed by HF/B3LYP methods using 6-31G(d,p) basis set. To estimate the electronic transitions, the UV spectra of title compound are predicted in gas phase and ethanol. The obtained absorption maxima at 389.94 nm (in ethanol) is predicted possibly due to HOMO→LUMO transition with 85% contribution and assigned as π-π*. The MESP map shows that the negative potential sites are localized on oxygen atom (O10) as well as the positive potential sites are identified around the hydrogen and ring carbon atoms. The analysis of Fukui indices is also carried out to distinguish the nucleophilic and electrophiic centers. The prediction of reactive sites by MESP is well supported by this Fukui indices analysis. The correlations between the statistical thermodynamics and temperature are also obtained. It is seen that the heat capacities, entropies and enthalpies increase with increasing the intensities of the molecular vibrations. Furthermore, the first hyperpolarizability of 5-chloro-2-nitroanisole is calculated and the results are discussed. This result indicates that 5-chloro-2-nitroanisole is a good candidate of nonlinear optical materials.

  19. NMR study of the epoxidation of liquid hydrolyzed poly-butadiene and meta-chloro-per-benzoic acid; Estudo atraves de RMN da reacao de epoxidacao de polibutadieno liquido hidroxilado (PBLH) e acido m-cloro perbenzoico (AMCPB)

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Marcelo [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Quimica; Akcelrud, L [Universidade Federal, Rio de Janeiro, RJ (Brazil). Escola de Quimica; Menezes, Sonia Cabral de [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas

    1994-12-31

    This work presents a study concerning the selectivity of the different configurations of the double bond present in liquid hydrolyzed poly-butadiene towards the epoxidation reaction with meta-chloro-per-benzoic acid through hydrogen-1, carbon-13 NMR aiming the production of new materials, varying the epoxidation level 12 refs., 7 figs., 4 tabs.

  20. Design, synthesis, and pharmacology of a highly subtype-selective GluR1/2 agonist, (RS)-2-amino-3-(4-chloro-3-hydroxy-5-isoxazolyl)propionic acid (Cl-HIBO)

    DEFF Research Database (Denmark)

    Bjerrum, Esben J; Kristensen, Anders S; Pickering, Darryl S

    2003-01-01

    On the basis of structural studies, chloro-homoibotenic acid (Cl-HIBO) was designed and synthesized. Cl-HIBO was characterized in binding and electrophysiology experiments on native and cloned subtypes of GluRs. Electrophysiological selectivities ranged from 275 to 1600 for GluR1/2 over GluR3/4. ...

  1. An excited-state intramolecular photon transfer fluorescence probe for localizable live cell imaging of cysteine

    Science.gov (United States)

    Liu, Wei; Chen, Wen; Liu, Si-Jia; Jiang, Jian-Hui

    2017-03-01

    Small molecule probes suitable for selective and specific fluorescence imaging of some important but low-concentration intracellular reactive sulfur species such as cysteine (Cys) pose a challenge in chemical biology. We present a readily available, fast-response fluorescence probe CHCQ-Ac, with 2-(5‧-chloro-2-hydroxyl-phenyl)-6-chloro-4(3 H)-quinazolinone (CHCQ) as the fluorophore and acrylate group as the functional moiety, that enables high-selectivity and high-sensitivity for detecting Cys in both solution and biological system. After specifically reacted with Cys, the probe undergoes a seven-membered intramolecular cyclization and released the fluorophore CHCQ with excited-state intramolecular photon transfer effect. A highly fluorescent, insoluble aggregate was then formed to facilitate high-sensitivity and high-resolution imaging. The results showed that probe CHCQ-Ac affords a remarkably large Stokes shift and can detect Cys under physiological pH condition with no interference from other analytes. Moreover, this probe was proved to have excellent chemical stability, low cytotoxicity and good cell permeability. Our design of this probe provides a novel potential tool to visualize and localize cysteine in bioimaging of live cells that would greatly help to explore various Cys-related physiological and pathological cellular processes in cell biology and diagnostics.

  2. Binding of heavy metal ions in aggregates of microbial cells, EPS and biogenic iron minerals measured in-situ using metal- and glycoconjugates-specific fluorophores

    Science.gov (United States)

    Hao, Likai; Guo, Yuan; Byrne, James M.; Zeitvogel, Fabian; Schmid, Gregor; Ingino, Pablo; Li, Jianli; Neu, Thomas R.; Swanner, Elizabeth D.; Kappler, Andreas; Obst, Martin

    2016-05-01

    Aggregates consisting of bacterial cells, extracellular polymeric substances (EPS) and Fe(III) minerals formed by Fe(II)-oxidizing bacteria are common at bulk or microscale chemical interfaces where Fe cycling occurs. The high sorption capacity and binding capacity of cells, EPS, and minerals controls the mobility and fate of heavy metals. However, it remains unclear to which of these component(s) the metals will bind in complex aggregates. To clarify this question, the present study focuses on 3D mapping of heavy metals sorbed to cells, glycoconjugates that comprise the majority of EPS constituents, and Fe(III) mineral aggregates formed by the phototrophic Fe(II)-oxidizing bacteria Rhodobacter ferrooxidans SW2 using confocal laser scanning microscopy (CLSM) in combination with metal- and glycoconjugates-specific fluorophores. The present study evaluated the influence of glycoconjugates, microbial cell surfaces, and (biogenic) Fe(III) minerals, and the availability of ferrous and ferric iron on heavy metal sorption. Analyses in this study provide detailed knowledge on the spatial distribution of metal ions in the aggregates at the sub-μm scale, which is essential to understand the underlying mechanisms of microbe-mineral-metal interactions. The heavy metals (Au3+, Cd2+, Cr3+, CrO42-, Cu2+, Hg2+, Ni2+, Pd2+, tributyltin (TBT) and Zn2+) were found mainly sorbed to cell surfaces, present within the glycoconjugates matrix, and bound to the mineral surfaces, but not incorporated into the biogenic Fe(III) minerals. Statistical analysis revealed that all ten heavy metals tested showed relatively similar sorption behavior that was affected by the presence of sorbed ferrous and ferric iron. Results in this study showed that in addition to the mineral surfaces, both bacterial cell surfaces and the glycoconjugates provided most of sorption sites for heavy metals. Simultaneously, ferrous and ferric iron ions competed with the heavy metals for sorption sites on the organic

  3. Characterization of changes in IgG associated oligosaccharide profiles in rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis using fluorophore linked carbohydrate electrophoresis.

    Science.gov (United States)

    Martin, K; Talukder, R; Hay, F C; Axford, J S

    2001-07-01

    To investigate fluorophore linked carbohydrate electrophoresis (FCE) as a method of analyzing serum immunoglobulin G (IgG) oligosaccharides in healthy individuals and those with rheumatic disease and compare with lectin binding assays of carbohydrate composition. IgG was isolated from patients with rheumatoid arthritis (RA) (n = 21), ankylosing spondylitis (AS) (n = 20), psoriatic arthritis (PsA) (n = 20), and healthy adults (n = 36). IgG oligosaccharides were released enzymatically, fluorescently labelled using 8 aminonaphthalene-136 trisulfonic acid; and identification of the oligosaccharide bands was by stepwise enzymatic degradation. Comparison of FCE was made with lectin binding analysis in which the lectins Ricinus communis (RCA1) and Bandeiraea simplicifolia (BSII) were used to detect galactose (Gal) and N-acetylglucosamine (GlcNAc), respectively. Each disease could be differentiated from healthy adults on the basis of Band 1 asialodigalacto core fucosylated oligosaccharide (gf2) intensity (p = 0.001), but not from each other. Reduced levels of different sugars were associated with specific diseases: reduced gf2 with RA (p < 0.001), PsA (p < 0.001) and AS (p < 0.02), reduced Band 5 disialo-digalacto core fucosylated (a2f) oligosaccharide with AS (p < 0.001), reduced Band 6 disialo-digalacto (a2) oligosaccharide with AS (p < 0.001) and PsA (p = 0.021). All diseases were associated with a significant increase in Band 4 asialo-agalacto core fucosylated oligosaccharide (g0f) (p < 0.001). In RA, FCE band intensities correlated with sugar quantity when identified using lectin binding analysis (p < 0.003). In contrast, there was no correlation between the same bands in healthy individuals. FCE is an accurate method of analyzing IgG associated oligosaccharides and reveals unique band patterns or sugar prints associated with healthy adults and patients with RA, PsA, and AS, and comparison with lectin binding analysis suggests undetected RA glycoprotein structural

  4. Fluorophore appended saccharide cyclophane: self-association, fluorescent properties, heterodimers with cyclodextrins, and cross-linking behavior with peanut agglutinin of dansyl-modified saccharide cyclophane.

    Science.gov (United States)

    Hayashida, Osamu; Hamachi, Itaru

    2004-05-14

    A saccharide cyclophane bearing an environment-sensitive fluorophore (1) was prepared by introducing not only three branches with a terminal galactose residue but also one with a dansyl moiety into a tetraaza[6.1.6.1]paracyclophane skeleton. Self-association behavior of the dansyl-appended saccharide cyclophane was characterized in aqueous media by fluorescence spectroscopy and dynamic light scattering measurements. At least in the concentrations below 1.0 x 10(-5) M, saccharide cyclophane 1 existed in a monomeric state, whereas it tended to form self-aggregated complexes in the higher concentration. Solvent polarity dependency on the emission spectra of 1 was examined by fluorescence spectroscopy. With increasing dioxane contents in dioxane/water solvents, the fluorescence intensity originating from the dansyl moiety of 1 increased along with a concomitant blue shift of the fluorescence maximum (lambda(em)). In the monomeric state of 1 in water, the dansyl moiety of 1 was not fully included into its cyclophane cavity but partially exposed to the bulk aqueous phase. In the higher concentration ranges in an aggregate state, however, the dansyl group of 1 was located in the apolar cyclophane cavity whose microenvironment was equivalent to the polarity of 1-butanol evaluated on the basis of a correlation between lambda(em) and solvent polarity. This indicates an intermolecular inclusion of the dansyl moiety within the cyclophane. When cyclodextrin (CD) was mixed with 1, the dansyl group of 1 was bound to an internal cavity of CD such as gamma-CD, beta-CD, 6-O-alpha-glucosyl-beta-CD, and 6-O-alpha-maltosyl-beta-CD with binding constants of 7.5 x 10(2), 7.8 x 10(2), 7.7 x 10(2), and 6.0 x 10(2) M(-1), respectively. Such a supramolecular assembling of dansyl-modified cyclophane 1 and CDs caused changes of the fluorescence spectra as well as appearance of induced CD bands in aqueous media. Furthermore, saccharide cyclophane 1 was selectively bound to peanut agglutinin

  5. Orthogonal Electric Field Measurements near the Green Fluorescent Protein Fluorophore through Stark Effect Spectroscopy and pKa Shifts Provide a Unique Benchmark for Electrostatics Models.

    Science.gov (United States)

    Slocum, Joshua D; First, Jeremy T; Webb, Lauren J

    2017-07-20

    Measurement of the magnitude, direction, and functional importance of electric fields in biomolecules has been a long-standing experimental challenge. pK a shifts of titratable residues have been the most widely implemented measurements of the local electrostatic environment around the labile proton, and experimental data sets of pK a shifts in a variety of systems have been used to test and refine computational prediction capabilities of protein electrostatic fields. A more direct and increasingly popular technique to measure electric fields in proteins is Stark effect spectroscopy, where the change in absorption energy of a chromophore relative to a reference state is related to the change in electric field felt by the chromophore. While there are merits to both of these methods and they are both reporters of local electrostatic environment, they are fundamentally different measurements, and to our knowledge there has been no direct comparison of these two approaches in a single protein. We have recently demonstrated that green fluorescent protein (GFP) is an ideal model system for measuring changes in electric fields in a protein interior caused by amino acid mutations using both electronic and vibrational Stark effect chromophores. Here we report the changes in pK a of the GFP fluorophore in response to the same mutations and show that they are in excellent agreement with Stark effect measurements. This agreement in the results of orthogonal experiments reinforces our confidence in the experimental results of both Stark effect and pK a measurements and provides an excellent target data set to benchmark diverse protein electrostatics calculations. We used this experimental data set to test the pK a prediction ability of the adaptive Poisson-Boltzmann solver (APBS) and found that a simple continuum dielectric model of the GFP interior is insufficient to accurately capture the measured pK a and Stark effect shifts. We discuss some of the limitations of this

  6. Synthesis and evaluation of fluorine-substituted phenyl acetate derivatives as ultra-short recovery sedative/hypnotic agents.

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    Heng Zhang

    Full Text Available BACKGROUND: Soft drugs are molecules that are purposefully designed to be rapidly metabolized (metabolically labile. In anesthesia, the soft drug is useful because it enables precise titration to effect and rapid recovery, which might allow swift and clear-headed recovery of consciousness and early home readiness. Propofol may cause delayed awakening after prolonged infusion. Propanidid and AZD3043 have a different metabolic pathway compared to propofol, resulting in a short-acting clinical profile. Fluorine imparts a variety of properties to certain medicines, including an enhanced absorption rate and improved drug transport across the blood-brain barrier. We hypothesized that the introduction of fluorine to the frame structure of propanidid and AZD3043 would further accelerate the swift and clear-headed recovery of consciousness. To test this hypothesis, we developed a series of fluorine-containing phenyl acetate derivatives. METHODOLOGY/PRINCIPAL FINDINGS: Fluorine-containing phenyl acetate derivatives were synthesized, and their hypnotic potencies and durations of LORR following bolus or infusion administration were determined in mice, rats and rabbits. The metabolic half-lives in the blood of various species were determined chromatographically. In vitro radioligand binding and γ-aminobutyric acidA (GABAA receptor electrophysiology studies were performed. Among the 12 synthesized fluorine-containing phenyl acetate derivatives, compound 5j induced comparable duration of LORR with AZD3043, but more rapid recovery than AZD3043, propanidid and propofol. The time of compound 5j to return to walk and behavioral recovery are approximately reduced by more than 50% compared to AZD3043 in mice and rats and rabbits. The HD50 of compound 5j decreased with increasing animal size. CONCLUSIONS/SIGNIFICANCE: The rapid recovery might make compound 5j suitable for precise titration and allow swift and clear-headed recovery of consciousness and early home

  7. Control of charge transfer by conformational and electronic effects: Donor-donor and donor-acceptor phenyl pyrroles

    International Nuclear Information System (INIS)

    Neubauer, Antje; Bendig, Juergen; Rettig, Wolfgang

    2009-01-01

    Derivatives of N-pyrrolobenzene with a para-donor and a para-acceptor substituent on the benzene ring are compared. It is shown that by a suitable increase of the donor strength of the pyrrolo group, CT fluorescence can be achieved even for donor-donor-substituted benzenes. The ICT emission for sterically hindered compounds is more forbidden than that of unhindered phenyl pyrroles. This suggests conformational effects which induce a narrower twist angle distribution around a perpendicular minimum in the excited state.

  8. Effects of phenylated compounds of methylglyoxal bis(guanylhydrazone) on diamine oxidase activity from rat small intestine.

    Science.gov (United States)

    Balaña-Fouce, R; Pulido, T G; Escudero, D O; Sanz-Sanchez, F

    1986-01-01

    Two phenylated compounds of methylglyoxal bis(guanylhydrazone), potentially inhibitors of diamine oxidase activity, have been synthesized: phenylglyoxal bis(guanylhydrazone) and diphenylglyoxal bis(guanylhydrazone). Their inhibitory capacity was tested: while PGBG was able to reduce the enzyme activity by 50% at 1.3 microM, DPGBG was only able to reduce diamine oxidase activity by less than 2% at a concentration 1000-fold higher. The inhibition of PGBG was non-competitive and the Ki calculated by a Dixon plot was estimated as 1.7 microM.

  9. Effects of methylglyoxal bis(guanylhydrazone) and two phenylated analogues on S-adenosylmethionine decarboxylase activity from Eimeria stiedai (Apicomplexa).

    Science.gov (United States)

    San-Martín Núñez, B; Alunda, J M; Balaña-Fouce, R; Ordóñez Escudero, D

    1987-01-01

    1. Activity of S-adenosylmethionine decarboxylase, one of the rate-limiting enzymes of polyamine biosynthesis, was determined in oocysts of Eimeria stiedai, a coccidian parasite of the rabbit. 2. Several properties of the enzyme were compared to the mammalian enzyme. It showed considerably less substrate affinity than the analog enzyme from the rabbit. 3. The E. stiedai enzyme showed a low sensitivity to methylglyoxal bis(guanylhydrazone), a frequently used inhibitor of the enzyme in mammals, and two phenylated derivatives. 4. Results with the inhibitors are discussed in view of their potential use in chemotherapy.

  10. Crystal structure of 1-{4-hydroxy-3-[(pyrrolidin-1-ylmethyl]phenyl}-3-phenylprop-2-en-1-one

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    Abdullah Aydın

    2016-05-01

    Full Text Available In the title compound, C20H21NO2, the pyrrolidine ring adopts an envelope conformation with the N atom at the flap position. The central benzene ring makes dihedral angles of 21.39 (10 and 80.10 (15° with the phenyl ring and the mean plane of the pyrrolidine ring, respectively. The molecular conformation is stabilized by an intramolecular O—H...N hydrogen bond, which closes an S(6 ring. A weak C—H...π interaction is observed in the crystal.

  11. 3-Phenoxymethyl-6-phenyl-1,2,4-triazolo[3,4-b][1,3,4]thiadiazole

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    Shaaban K. Mohamed

    2016-04-01

    Full Text Available In the title compound, C16H12N4OS, the bicyclic triazolothiadiazole core is approximately planar, with an r.m.s. deviation of 0.018 Å. The phenyl rings are inclined to its mean plane by 7.66 (7 and 71.79 (7°. In the crystal, molecules are linked via a C—H...π interaction and a π–π interaction [intercentroid distance = 3.2942 (9 Å] involving inversion-related triazole rings. These interactions result in the formation of chains propagating along [10-1].

  12. cis-Bis(O-methyl-dithio-carbonato-κ(2) S,S')bis-(tri-phenyl-phosphane-κP)ruthenium(II).

    Science.gov (United States)

    Valerio-Cárdenas, Cintya; Hernández-Ortega, Simón; Reyes-Martínez, Reyna; Morales-Morales, David

    2013-01-01

    In the title compound, [Ru(CH3OCS2)2(C18H15P)2], the Ru(II) atom is in a distorted octa-hedral coordination by two xanthate anions (CH3OCS2) and two tri-phenyl-phosphane (PPh3) ligands. Both bidentate xanthate ligands coordinate the Ru(II) atom with two slightly different Ru-S bond lengths but with virtually equal bite angles [71.57 (4) and 71.58 (3)°]. The packing of the complexes is assured by C-H⋯O and C-H⋯π inter-actions.

  13. (O-Methyl di­thio­carbonato-κS)tri­phenyl­tin(IV)

    Science.gov (United States)

    Javed, Fatima; Ali, Saqib; Shah, Wajid; Tahir, M. Nawaz; Ullah, Hameed

    2013-01-01

    In the title compound, [Sn(C6H5)3(C2H3OS2)], the SnIV atom adopts a distorted SnC3S tetra­hedral coordination geometry. A short Sn⋯O contact [2.988 (4) Å] is also present. The phenyl rings are each disordered over two sets of sites with an occupancy ratio of 0.550 (8):0.450 (8). The crystal studied was found to be a racemic twin with a twin component ratio of 0.57 (18):0.43 (18). PMID:23794982

  14. Synthesis and Activity of a New Series of(Z-3-Phenyl-2-benzoylpropenoic Acid Derivatives as Aldose Reductase Inhibitors

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    Shao-Jie Wang

    2007-04-01

    Full Text Available During the course of studies directed towards the discovery of novel aldose reductase inhibitors for the treatment of diabetic complications, we synthesized a series of new (Z-3-phenyl-2-benzoylpropenoic acid derivatives and tested their in vitro inhibitory activities on rat lens aldose reductase. Of these compounds, (Z-3-(3,4-dihydroxyphenyl-2-(4-methylbenzoylpropenoicacid(3k was identified as the most potent inhibitor, with an IC50 of 0.49μM. The theoretical binding mode of 3k was obtained by simulation of its docking into the active site of the human aldose reductase crystal structure.

  15. Synthesis and Biological Activity of 3-[Phenyl(1,3-thiazol-2-yl-amino]propanoic Acids and Their Derivatives

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    Vytautas Mickevičius

    2013-12-01

    Full Text Available New N,N-disubstituted β-amino acids and their derivatives with thiazole, aromatic, and heterocyclic substituents were synthesized from N-phenyl-N-thiocarbamoyl-β-alanine by the Hantzsch method; derivatives with hydrazone fragments were also obtained. Some of the synthesized compounds exhibited discrete antimicrobial activity, and 3-[(4-oxo-4,5-dihydro-1,3-thiazol-2-yl(phenylamino]propanoic acid was found to promote rapeseed growth and to increase seed yield and oil content.

  16. Contribution to the study of gamma radiolysis of 2-furyl butyl or substituted phenyl ketones in isopropanol

    International Nuclear Information System (INIS)

    El Dessouky Aly, M.M.

    1982-03-01

    The following ketones: 2-furyl butyl ketone (I), 2 furyl phenyl ketone (II), 2-furyl p-methylphenyl ketone (III) and 2-furyl p-methoxyphenyl ketone (IV) were synthesised and characterised. The yields of hydrogen and methane obtained during radiolysis of the mixtures ketones (I to IV)-2-propanol were determined. These yields are always lower than with pure 2-propanol. Radiolysis products for ketones (I) and (II) are studied. Analysis of radiolitical products were conducted by gas chromatography. Effect of radiation dose and ketone concentration is determined. Reaction mechanisms are studied [fr

  17. (E-4-(2,5-Dimethoxybenzylidene-2-phenyl-1,3-oxazol-5(4H-one

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    Abdullah Mohamed Asiri

    2009-08-01

    Full Text Available The central azalactone ring in the title compound, C18H15NO4, is planar (r.m.s. deviation 0.05, 0.12 Å in both independent molecules comprising the asymmetric unit. The benzylidene substituent is coplanar with this ring [dihedral angle between the planes = 1.8 (1° in the first molecule and 2.8 (1° in the second], as is the phenyl substitutent [dihedral angle between rings = 4.6 (1 and 9.7 (1°, respectively].

  18. Novel L-Dopa and dopamine prodrugs containing a 2-phenyl-imidazopyridine moiety.

    Science.gov (United States)

    Denora, Nunzio; Laquintana, Valentino; Lopedota, Angela; Serra, Mariangela; Dazzi, Laura; Biggio, Giovanni; Pal, Dhananjay; Mitra, Ashim K; Latrofa, Andrea; Trapani, Giuseppe; Liso, Gaetano

    2007-07-01

    The aim of this study was to gain insight into the feasibility of enhancing the delivery of L-Dopa and dopamine to the brain by linking these neurotransmitters and L-Dopa ethyl ester to 2-phenyl-3-carboxymethyl-imidazopyridine compounds giving rise to the so-called Dopimid compounds. A number of Dopimid compounds were synthesized and both stability and binding studies to dopaminergic and benzodiazepine receptors were performed. To evaluate whether Dopimid compounds are P-gp substrates, [(3)H]ritonavir uptake experiments and bi-directional transport studies on confluent MDCKII-MDR1 monolayers were carried out. The brain penetration properties of Dopimid compounds were estimated by the Clark's computational model and evaluated by investigation of their transport across BBMECs monolayers. The dopamine levels following the intraperitoneal administration of the selected Dopimid compounds were measured in vivo by using brain microdialysis in rat. Tested compounds were adequately stable in solution buffered at pH 7.4 but undergo faster cleavage in dilute rat serum at 37 degrees C. Receptor binding studies showed that Dopimid compounds are essentially devoid of affinity for dopaminergic and benzodiazepine receptors. [(3)H]ritonavir uptake experiments indicated that selected Dopimid compounds, like L-Dopa and dopamine hydrochloride, are not substrates of P-gp and it was also confirmed by bi-directional transport experiments across MDCKII-MDR1 monolayers. By Clark's model a significant brain penetration was deduced for L-Dopa ethyl ester and dopamine derivatives. Transport studies involving BBMECs monolayers indicated that some of these compounds should be able to cross the BBB. Interestingly, the rank order of apparent permeability (P (app)) values observed in these assays parallels that calculated by the computational approach. Brain microdialysis experiments in rat showed that intraperitoneal acute administration of some Dopimid compounds induced a dose-dependent increase

  19. Novel adducts from the reaction of 1-chloro-3-buten-2-one with 2'-deoxyguanosine. Structural characterization and potential as tools to investigate 1,3-butadiene carcinogenicity.

    Science.gov (United States)

    Zheng, Jin; Li, Yan; Yu, Ying-Xin; An, Jing; Zhang, Xin-Yu; Elfarra, Adnan A

    2015-01-25

    1-Chloro-3-buten-2-one (CBO) is a potential reactive metabolite of 1,3-butadiene (BD), a carcinogenic air pollutant. To develop tools that may help investigate the role of CBO in BD carcinogenicity and to develop biomarkers that can be used to assess BD exposure, the reaction of CBO with 2'-deoxyguanosine (dG) under in vitro physiological conditions (pH 7.4, 37°C) was investigated and the products (designated as CG-1, CG-2, CG-3, CG-4, CG-5, and CG-6 based on their retention times on HPLC) were characterized by MS and NMR spectroscopy. The structures of CG-1, CG-2, CG-3, and CG-4 were 1,N2-(3-hydroxy-3-hydroxymethylpropan-1,3-diyl)-2'-deoxyguanosine, N7-(4-chloro-3-oxobutyl)-2'-deoxyguanosine, N7,8-(3-hydroxy-3-chloromethylpropan-1,3-diyl)guanine and N2-(4-chloro-3-oxobutyl)-2'-deoxyguanosine, respectively. CG-5 and CG-6, a pair of diastereomers, were characterized as 1,N2-(3-hydroxy-3-chloromethylpropan-1,3-diyl)-2'-deoxyguanosine. CG-1 was stable under in vitro physiological conditions, whereas CG-2, CG-3, CG-4, and CG-5/6 were unstable and exhibited the half-lives at CG-2 decomposed primarily via a retro-Michael reaction to produce dG and CBO, with only a small fraction of CG-2 degrading to CG-3. Decomposition of CG-4 proceeded via a cyclization reaction and/or replacement of the chlorine atom by a hydroxyl group to form 1,N2-(1-hydroxy-1-hydroxymethylpropan-1,3-diyl)-2'-deoxyguanosine (CG-4D1) and N(2)-(4-hydroxy-3-oxobutyl)-2'-deoxyguanosine (CG-4D2), whereas decomposition of CG-5/6 yielded CG-1. Collectively, the newly characterized CBO adducts could be used to investigate the role of CBO in the mechanism of BD carcinogenicity and could also be used to develop biomarkers for BD exposure. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. Synthesis and study of effects of new 4-chloro – amodiaquine analogues against two resistant and sensitive forms to chloroquine Plasmodium Falciparum, in vitro

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    afra Khosravi

    2009-03-01

    Full Text Available Background: Resistance to chloroquine (CQ in Plasmodium falciparum malaria has become a major health concern of the developing countries.This resistance has prompted a re-examination of the pharmacology of alternative antimalarials that may be effective against resistant strains. Amodiaquine (AQ is a 4-aminoquinoline antimalarial which is effective against many chloroquine-resistant strains of P. falciparum. However, clinical use of AQ has been severely restricted because of associations with hepatotoxicity and agranulocytosis. The aim of this study was to examine the effects of replacing the 4’OH function of amodiaquine with either chlorine or fluorine. Materials and Methods: A successful four-step synthesis of a new series of 4-chloro analogues has been designed and applied to the synthesis of an array of 10 analogues. Malaria parasites were maintained in continuous culture using the method of Jensen and Trager. Cultures were grown in flasks containing human erythrocytes (2-5% with parasitemia in the range of 1% to 10% suspended in RPMI 1640 medium supplemented with 25 mM HEPES and 32 mM NaHCO3, and 10% human serum (complete medium. Cultures were gassed with a mixture of 3% O2, 6% CO2 and 91% N2 and were kept in a 30 degree temperature. Results: It is apparent that several analogues had very potent antimalarial activity against both strains of the parasite. In particular 5b, 5c and 5i were not only active in the single nanomolar range, but they also displayed little cross-resistance. Against the sensitive HB3 strain, these analogues were superior to chloroquine and slightly more potent than amodiaquine. Activity was reduced when the side-chain was large (eg. dibutyl analogue and pyridine analogues, 5g and 5j respectively. Discussion: In a four - step Process, 10 different chloro - amodiaquine were synthesized which showed (in vitro Promising effects against chloroquine resistant strains of Plasmodium falciparum. It is clear that the 4’chloro