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Sample records for 3-hydroxy-2-formylpyridine semicarbazone synthesis

  1. Organotin Compound Derived from 3-Hydroxy-2-formylpyridine Semicarbazone: Synthesis, Crystal Structure, and Antiproliferative Activity

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    Joanna Wiecek

    2010-01-01

    Full Text Available The novel diphenyltin(IV compound [Ph2(HyFoScSn] (2, where H2HyFoSc (1 is 3-hydroxy-2-formylpyridine semicarbazone, was prepared and characterized by vibrational and NMR (1H, 13C spectroscopy. The structure of [Ph2(HyFoScSn] was confirmed by single-crystal X-ray crystallography. The doubly deprotonated ligand is coordinated to the tin atom through the enolic-oxygen, the azomethine-nitrogen, and phenolic-oxygen, and so acts as an anionic tridentate ligand with the ONO donors. Two carbon atoms complete the fivefold coordination at the tin(IV center. Intermolecular hydrogen bonding, C-H→, and → interactions combine to stabilize the crystal structure. Compounds 1 and 2 have been evaluated for antiproliferative activity in vitro against the cells of three human tumor cell lines: MCF-7 (human breast cancer cell line, T24 (bladder cancer cell line, A549 (nonsmall cell lung carcinoma, and a mouse fibroblast L-929 cancer cell line.

  2. An Efficient Procedure for Microscale Synthesis of Semicarbazones

    Science.gov (United States)

    Pandita, Sangeeta; Goyal, Samta; Passey, Sarita

    2004-01-01

    A successful microscale fusion of semicarbazones, or transformation of carbonyl compounds into semicarbazones is performed through an effective grinding system. The donning of protective attire is advised to avoid the hazardous effects of semicarbazide hydrochloride during the fusion process.

  3. Synthesis and Anticonvulsant Activity of Some Newer Semicarbazone Derivatives

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    Shahnawaz Sameem

    2012-07-01

    Full Text Available A series of 4-(3-Chlorophenyl-1-(substituted acetophenone semicarbazones 3(a-j was synthesized by starting with 3-chloroaniline which on reaction with sodium cyanate yielded 1-(3’-chlorophenyl urea (1 followed by reaction with hydrazine hydrate in the presence of ethanol gave 4-(3’-chlorophenyl semicarbazide (2. Compound (2 on condensation with substituted acetophenone gets converted in to final compounds 3(a-j. The purity of the newer compounds was checked by m.p. and TLC analysis. The structures of the newly synthesized compounds were characterized by FTIR, 1H NMR, EIMS-spectral data and elemental analysis. All the synthesized compounds were evaluated for their anticonvulsant activity by Maximal Electroshock (MES method by using phenytoin as standard at a concentration of 30 mg/kg. The anticonvulsant effect of the newly synthesized compounds was assessed by absence or reduction of hind limb tonic extensor phase. Among the synthesized derivatives compounds 3e and 3j were found to be the most potent compounds in the series.

  4. Synthesis and evaluation of 4-substituted semicarbazones of levulinic acid for anticonvulsant activity

    Institute of Scientific and Technical Information of China (English)

    AGGARWAL Navneet; MISHRA Pradeep

    2005-01-01

    Objective: A series of 4-aryl substituted semicarbazones of levulinic acid (4-oxo pentanoic acid) was designed and synthesized to meet the structural requirements essential for anticonvulsant activity. Methods: All the compounds were evaluated for anticonvulsant activity. Anticonvulsant activity was determined after intraperitoneal (i.p.) administration to mice by maximal electroshock (MES) and subcutaneous metrazol (ScMet) induced seizure methods and minimal motor impairment was determined by rotorod test. Results: A majority of the compounds exhibited significant anticonvulsant activity after intraperitoneal administration. In the present study 4-(4'-fluoro phenyl) levulinic acid semicarbazone emerged as the most active molecule, showing broad spectrum of activity with low neurotoxicity. Unsubstituted levulinic acid semicarbazone was found to be inactive in all the screens. Conclusion: The results obtained validate the hypothesis that presence of an aryl group near the semicarbazone moiety is essential for anticonvulsant activity. The results also indicate that the hydrophilic-hydrophobic site can accommodate hydrophilic groups.

  5. Synthesis, EPR, Electronic and Magnetic Studies on Cobalt (II) Complexes of Semicarbazone and Thiosemicarbazone

    International Nuclear Information System (INIS)

    Cobalt (II) complexes having the general composition Co(L2) X2 [where Lisopropyl methyl ketone semicarbazone (LLA), isopropyl methyl ketone thiosemicarbazone (LLB), 4-aminoacetophenone semicarbazone (LLC) and4-aminoacetophenone thiosemicarbazone (LLD) and X=Cl] have been synthesized. All the Co(II) complexes reported here have been characterized by elemental analyses, magnetic moments, IR, electronic and EPR spectral studies. All the complexes were found to have magnetic moments corresponding to three unpaired electrons. The possible geometries of the complexes were assigned on the basis of electronic infrared and EPR spectral studies. (author) = = = = = = = = = = = = = = =

  6. Design and synthesis of some novel 4-(4-substituted aryl semicarbazones as anticonvulsant agents

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    Singh Anita

    2010-01-01

    Full Text Available In the present study, a series of 4-(4-substituted aryl semicarbazones were synthesized from substituted anilines and subsequently evaluated for their anticonvulsant activities. The anticonvulsant activities were established by the anticonvulsant drug development (ADD programme NIH, USA using experimental animal, adult male FCM mice (20-25 g and adult Sprague-Dawley rats (100-150 g and screened against electroshock seizure, subcutaneous metrazole and minimal neurotoxicity tests in mice. Compound 7 was found equipotent to carbamazepine in both MES and ScPTZ tests. This study has highlighted the importance of distal alkyl chain which influences the anticonvulsant activity.

  7. Synthesis, Molecular docking and Biological evaluation of 4-Cycloalkylidineamino 1, 2-Naphthoquinone Semicarbazones as Anticancer agents

    Institute of Scientific and Technical Information of China (English)

    Shubhanjali Shukla; Radhey Shyam Srivastava; Sushant Kumar Shrivastava; Ajit Sodhi; Pankaj Kumar

    2012-01-01

    Objective: In an effort to etablish new candidates with improved antineoplastic activity, 4-cycloalkylidineamino 1,2-naphthoquinone semicarbazones were synthesized, characterized and evaluated for anticancer activity. Method: The desired compounds were synthesized by condensation of 4- amino1, 2-naphthoquinone with cyclic ketones and further subsequent reaction of this product with semicarbazide hydrochloride. Compounds were characterized by FT-IR, 1H NMR, 13C NMR, elemental analysis and screened for antiproliferative activity against three human cancer cell lines (HepG2, MG-63 and MCF-7) by MTT assay using doxorubicin as standard. Docking was performed by using the Glide 5.7 integrated with Maestro 9.2 (Schrödinger, LLC, 2011) to understand the binding preference of synthesized compounds with target enzyme topoisomerase-II. Results: 4-(cyclohexylideneamino) [1, 2] naphthoquinone 2-semicarbazone was found to be most active cytotoxic agent against all cancer cell lines with IC50 values in the range of 5.58–6.31 µM. Results of molecular docking were also well correlated in vitro cytotoxicity assay. Insilico ADME studies revealed the drug likeliness of compounds. Conclusions: The synthesized compounds were found to have significant anticancer activity and able to enter in higher phases of the drug development process due to favorable pharmacokinetic properties.

  8. Design, Synthesis and Antiproliferative Activity of Novel Benzothiazole Derivatives Conjugated with Semicarbazone Scaffold.

    Science.gov (United States)

    Bao, Guanglong; Du, Baoquan; Ma, Yuxiu; Zhao, Meng; Gong, Ping; Zhai, Xin

    2016-01-01

    Two series of novel benzothiazole derivatives conjugated with semicarbazone scaffold were designed and synthesized through a structure-based molecular hybridization strategy. All the target compounds were evaluated for their cytotoxicity in vitro against three cancer cell lines (HT-29, MKN-45 and H460) by standard MTT assay. The pharmacological results indicated that seven compounds (17h-n) exhibited comparable or even better antiproliferative activity in comparison with reference drugs Sorafenib and PAC-1. Particularly, compound 17i displayed remarkable cytotoxicity against tested three cancer cell lines with IC50 values of 0.84, 0.06 and 0.52 µM, which were 4.3-, 36.6-, 4.2-folds more potent than Sorafenib and 1.2-, 13.7-, 6.9-times more active than PAC-1, respectively. PMID:26740207

  9. Design, synthesis and in vitro trypanocidal and leishmanicidal activities of novel semicarbazone derivatives.

    Science.gov (United States)

    Alves, Marina A; de Queiroz, Aline C; Alexandre-Moreira, Magna Suzana; Varela, Javier; Cerecetto, Hugo; González, Mercedes; Doriguetto, Antonio C; Landre, Iara M; Barreiro, Eliezer J; Lima, Lídia M

    2015-07-15

    Trypanosomatids are protozoan parasites that cause various diseases in human, such as leishmaniasis, Chagas disease and sleeping sickness. The highly syntenic genomes of the trypanosomatid species lead the assumption that they can encode similar proteins, indicating the possibility to design new antitrypanosomatid drugs with dual trypanosomicidal and leishmanicidal activities. In this work a series of compounds (6a-h and 7a-h), containing a semicarbazone scaffold as a peptide mimetic framework, was designed and synthesized. From this series compound 7g (LASSBio-1483) highlighted, showing dual in vitro trypanosomicidal and leishmanicidal activities, with potency similar to the standard drugs nifurtimox and pentamidine. This data, taken together with its good in silico druglikeness profile and its great chemical and plasma stability, make LASSBio-1483 (7g) a new antitrypanosomatid lead-candidate. PMID:26069927

  10. Synthesis and structural investigations of some five-coordinated oxovanadium(IV) complexes of 4[N-(benzylidene)amino] antipyrine semicarbazone

    International Nuclear Information System (INIS)

    The synthesis and spectral characteristics of a new series of five coordinated oxovanadium(IV) complexes of 4[N-(benzylidene) antipyrine semicarbazone (BAAPS) with general composition VOX2.BAAPS (X=Cl, Br, I, No3 or NCS) and VO(ClO4)2. BAAPS.H2O are reported together with molecular conductivity, molecular weights, magnetic susceptibility, infrared and electronic spectra. In all the complexes, the BAAPS behaves as neutral tridentate (N,N,O) ligand. (author). 12 refs., 3 tabs

  11. Copper(II) complexes derived from di-2-pyridyl ketone- N4-phenyl-3-semicarbazone: Synthesis and spectral studies

    Science.gov (United States)

    Reena, T. A.; Kurup, M. R. Prathapachandra

    2010-08-01

    Five copper(II) complexes [CuLCl] 2·CuCl 2·4H 2O ( 1), [CuLOAc] ( 2), [CuLNO 3] 2 ( 3), [CuLN 3] ( 4) and [CuLNCS]·3/2H 2O ( 5) of di-2-pyridyl ketone- N4-phenyl-3-semicarbazone (HL) were synthesized and characterized by elemental analyses and electronic, infrared and EPR spectral techniques. In all these complexes the semicarbazone undergoes deprotonation and coordinates through enolate oxygen, azomethine and pyridyl nitrogen atoms. All the complexes are EPR active due to the presence of an unpaired electron. EPR spectra of all the complexes in DMF at 77 K suggest axial symmetry and the presence of half field signals for the complexes 1 and 3 indicates dimeric structures.

  12. Microwave-assisted synthesis, anticonvulsant activity and quantum mechanical modelling of N-(4-bromo-3-methylphenyl)semicarbazones

    Institute of Scientific and Technical Information of China (English)

    SHALINI Mehta; YOGEESWARI Perumal; SRIRAM Dharmarajan; INDUJA Sridharan

    2007-01-01

    Objective: To study the effect of halo substitution on disubstituted aryl semicarbazones on the anticonvulsant potential and model the activity based on quantum mechanics. Methods: A series of twenty-six compounds of N4-(4-bromo-3-methylphenyl) semicarbazones were synthesized and evaluated for the anticonvulsant activity in the maximal electroshock seizure (MES) and subcutaneous pentylenetetrazole (scPTZ) seizure threshold tests. Some potential compounds were also tested in the subcutaneous strychnine (scSTY) and subcutaneous picrotoxin (scPIC) seizure threshold tests. The synthesized compounds were tested for behavioral impairment and CNS (central nervous system) depression in mice. Quantum mechanical modelling was carried out on these compounds to gain understanding on the structural features essential for activity. Results: Some compounds possessed broad spectrum anticonvulsant activity as indicated by their effect in pentylenetetrazole, strychnine, picrotoxin and maximal electroshock seizures models in resemblance to other aryl semicarbazone derivatives reported earlier. The higher the difference in HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) energy levels was, the greater was the activity profile. Conclusion: The pharmacophoric requirements for compounds to exhibit anticonvulsant activity that includes one aryl unit in proximity to a hydrogen donor-acceptor domain and an electron donor have been justified with the molecular orbital surface analysis of the synthesized compounds.

  13. Synthesis, characterization and chemical properties of 1-((E)-2-pyridinylmethylidene)semicarbazone manganese(II) and iron(II) complexes

    Science.gov (United States)

    Garbelini, Ellery Regina; Martin, Maria da Graça M. B.; Back, Davi Fernando; Evans, David John; Müller-Santos, Marcelo; Ribeiro, Ronny Rocha; Lang, Ernesto Schulz; Nunes, Fábio Souza

    2012-01-01

    Manganese(II) perchlorate and iron(II) chloride react with 2-formylpyridine semicarbazone (HCSpy) in boiling ethanol to produce [Mn II(HSCpy) 2](ClO 4) 2·C 2H 5OH and [Fe IICl(HSCpy)]Cl. The distorted octahedral manganese complex crystallizes in the triclinic system with space group P(-1). The ligand HSCpy is tridentate and is coordinated through two nitrogen and one oxygen atoms. Comparison of the bond distances with analogous transition metal complexes that have the same geometry revealed longer bonds for the manganese derivative, an outcome that correlates well with the radius of the metal ions. The iron(II) ion is tetracoordinated to one semicarbazone and one chloride. Mass spectrometry, conductivity measurements, Mössbauer, UV-VIS, FTIR and elemental analysis were all in accordance with the proposed composition and the plausible geometry of [FeCl(HSCpy)]Cl. Mass spectrometry unequivocally detected the presence of the [FeCl(HSCpy)] + ion with a m/ z of 254.97 and intensity of 2 × 10 5.

  14. SYNTHESIS AND BIOLOGICAL EVALUTION OF 3-CHLORO 2- METHYL PHENYL CARBAMOYL SUBSTITUTED SEMICARBAZONE DERIVATIVES AS POTENTIAL ANTICONVULSANT AGENTS

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    Laxmi Banjare

    2012-01-01

    Full Text Available A series of 3- chloro 2- methyl phenyl carbamoyl substituted semicarbazones (4-21 was synthesized and evaluated for anticonvulsant and CNS activities. The anticonvulsant activity of the synthesized compounds was established after intraperitoneal administration in three seizure models in mice which include maximalelectroshock seizure, subcutaneous pentylenetetrazole, and subcutaneous strychnine-induced seizure screens. All the test compounds were administered at doses of 30, 100, and 300 mg/kg body weight and the anticonvulsant activity was noted at 0.5 and 4 h time intervals after the drug administration . . Aryl semicarbazides have also been reported to display excellent anticonvulsant activity in mice and rats . In terms of interaction at the binding site, as proposed previously by Dimmock et al. the pharma-cophoric elements were thought to be a lipophilic aryl ring and hydrogen bonding semicarbazone moiety. The attach- ment of a second aryl ring designated as the distal ring to the proximal aryl ring to increase the van der Waal’s bonding at the binding site and to increase potency have also been reported. Substitutions in the aryl ring by halogens have been found to increase potency in the MES screen .

  15. Synthesis and characterization of semicarbazone of p-hydroxy-3-methoxy acetophenone (SPH3MA) single crystal

    Energy Technology Data Exchange (ETDEWEB)

    Janarthanan, S. [Department of Physics, Presidency College, Chennai, Tamilnadu (India); Rajan, Y.C. [Department of Materials Science, National Chiao Tung University, Taiwan (China); Umarani, P.R. [Department of Physics, Presidency College, Chennai, Tamilnadu (India); Selvakumar, S. [Department of Physics, L.N.G. College, Ponneri, Tamilnadu (India); Pandi, S., E-mail: srijana26@gmail.co [Department of Physics, Presidency College, Chennai, Tamilnadu (India)

    2011-01-15

    Single crystals of semicarbazone of p-hydroxy-3-methoxy acetophenone (SPH3MA) were grown by a slow evaporation solution growth technique at room temperature. This is the first report in the literature on the crystallization of SPH3MA. The cell parameters of the grown crystals were estimated by single crystal X-ray diffraction analysis. The various planes of reflection were identified from the XRD powder pattern. The presence of functional groups was identified from FTIR and {sup 1}H NMR. The results were found to be in accordance with the structure of the crystal. The formation of charge transfer complex was confirmed by UV-vis-NIR spectroscopy. The thermal stability of the grown crystal was studied by thermal analysis.

  16. Synthesis, structure and electrochemistry behavior of a cobalt(III) compound with azide and methyl 2-pyridyl ketone semicarbazone ligands

    Science.gov (United States)

    Shaabani, Behrouz; Khandar, Ali Akbar; Mahmoudi, Farzaneh; Balula, Salete S.; Cunha-Silva, Luís

    2013-08-01

    An unprecedented cobalt(III) compound with methyl 2-pyridyl ketone semicarbazone (HL) and the auxiliary azide ligand, [Co(L)2] [Co(L)(N3)3] (1) was synthesized and further characterized crystallographically and spectroscopically. Compound 1 crystallizes in the triclinic system and space group of P-1 and its structure consists of two mononuclear crystallographic units with metal chromophore comprising two cobalt(III) centers revealing distorted octahedral geometries and formed by distinct ligands in the inner coordination spheres. Interestingly, compound 1 represents the first complex formed by two distinct mononuclear units involving this ligand. As consequence of various donor and acceptor groups in both crystallographic units, there are several strong Nsbnd H⋯N and Nsbnd H⋯O hydrogen bonding interactions interconnecting adjacent moieties, ultimately leading to a three-dimensional supramolecular network. Furthermore, the electrochemical behavior of the HL and compound 1 were investigated.

  17. Synthesis and characterization of semicarbazone of p-hydroxy-3-methoxy acetophenone (SPH3MA) single crystal

    Science.gov (United States)

    Janarthanan, S.; Rajan, Y. C.; Umarani, P. R.; Selvakumar, S.; Pandi, S.

    2011-01-01

    Single crystals of semicarbazone of p-hydroxy-3-methoxy acetophenone (SPH3MA) were grown by a slow evaporation solution growth technique at room temperature. This is the first report in the literature on the crystallization of SPH3MA. The cell parameters of the grown crystals were estimated by single crystal X-ray diffraction analysis. The various planes of reflection were identified from the XRD powder pattern. The presence of functional groups was identified from FTIR and 1H NMR. The results were found to be in accordance with the structure of the crystal. The formation of charge transfer complex was confirmed by UV-vis-NIR spectroscopy. The thermal stability of the grown crystal was studied by thermal analysis.

  18. Ni(II, Pd(II and Pt(II complexes with ligand containing thiosemicarbazone and semicarbazone moiety: synthesis, characterization and biological investigation

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    SULEKH CHANDRA

    2008-07-01

    Full Text Available The synthesis of nickel(II, palladium(II and platinum(II complexes with thiosemicarbazone and semicarbazone of p-tolualdehyde are reported. All the new compounds were characterized by elemental analysis, molar conductance measurements, magnetic susceptibility measurements, mass, 1H-NMR, IR and electronic spectral studies. Based on the molar conductance measurements in DMSO, the complexes may be formulated as [Ni(L2Cl2] and [M(L2]Cl2 (where M = Pd(II and Pt(II due to their non-electrolytic and 1:2 electrolytic nature, respectively. The spectral data are consistent with an octahedral geometry around Ni(II and a square planar geometry for Pd(II and Pt(II, in which the ligands act as bidentate chelating agents, coordinated through the nitrogen and sulphur/oxygen atoms. The ligands and their metal complexes were screened in vitro against fungal species Alternaria alternata, Aspergillus niger and Fusarium odum, using the food poison technique.

  19. Synthesis, characterization and physiochemical information, along with antimicrobial studies of some metal complexes derived from an ON donor semicarbazone ligand

    Science.gov (United States)

    Siji, V. L.; Kumar, M. R. Sudarsana; Suma, S.; Kurup, M. R. Prathapachandra

    2010-06-01

    Eight new transition metal complexes of benzaldehyde- N(4)-phenylsemicarbazone have been synthesized and characterized by elemental analyses, molar conductance, electronic and infrared spectral studies. In all the complexes, the semicarbazone is coordinated as neutral bidentate ligand. 1H NMR spectrum of [Zn(HL) 2(OAc) 2] shows that there is no enolisation of the ligand in the complex. The magnetic susceptibility measurements indicate that Cr(III), Mn(II), Fe(III), Co(II) and Cu(II) complexes are paramagnetic and Ni(II) is diamagnetic. The EPR spectrum of [Mn(HL) 2(OAc) 2] in DMF solution at 77 K shows hyperfine sextet with low intensity forbidden lines lying between each of the two main hyperfine lines. The g values calculated for the [Cu(HL) 2SO 4] complex in frozen DMF, indicate the presence of unpaired electron in the d orbital. The metal ligand bonding parameters evaluated showed strong in-plane σ bonding and in-plane π bonding. The ligand and complexes were screened for their possible antimicrobial activities.

  20. Synthesis,Crystal Structure and Interaction with DNA of a Novel Chromium(Ⅲ) Complex Containing Salicylaldehyde Semicarbazone

    Institute of Scientific and Technical Information of China (English)

    YUE Lei; ZHOU Yin-Zhuang; LIU Jin-Li; TU Shu-Jie; XIAO Ling-Mei

    2009-01-01

    The novel chromium(Ⅲ) complex with salicylaldehydc semicarbazone was synthe-sized and characterized by IR spectra and single-crystal X-ray diffraction analysis.The crystal bclongs to the orthorhombic system,space group Pbca with a=8.9849(13),b=12.0475(16),c=34.522(5) A,V=3736.9(9) A3,Z=8,C16H18ClCrN6O5,Mr=461.81,De=1.642 g/cm3,F(000)=1896,μ(MoKa)=0.799 mm-1,the final R=0.0370 and wR=0.0827 for 2908 observed reflections with I > 20(I).The interaction between the chromium(Ⅲ) complex with calf thymus DNA (Ct-DNA) has been investigated by absorption spectroscopy,fluorescence spectroscopy and viscosity measurements.The results indicated that the complex was bonded to Ct-DNA through a non-classical intercalativc mode.

  1. 2-Benzoylpyridine semicarbazone

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    Daniel F. de Lima

    2008-01-01

    Full Text Available The title compound, C13H12N4O, crystallizes with two independent molecules in the asymmetric unit. The compound crystallizes as the ZE isomer, where Z and E refer to the configuration around the C=N and N—C bonds, respectively, with an N—H...Npy (py is pyridine intramolecular hydrogen bond. The dihedral angles between the least-squares planes through the semicarbazone group and the pyridyl ring are 22.70 (9 and 27.26 (9° for the two molecules. There are intermolecular N—H...O hydrogen bonds.

  2. (E-1-Phenylethanone semicarbazone

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    Hoong-Kun Fun

    2009-08-01

    Full Text Available In the title compound, C9H11N3O, the benzene ring is disordered over two positions with refined occupancies of 0.922 (5 and 0.078 (5. The program PLATON [Spek (2009. Acta Cryst. D65, 148–155] recommends the solution in the space group C2/m with a = 7.3050 (3, b = 6.6745 (2, c = 18.3853 (6 Å and β = 96.986 (2°. However, the large number of non-extinct reflections needed to be ignored if C2/m is chosen suggested that the space group is incorrect, even though the R values are lower than that for P21/c. The semicarbazone group is essentially planar, with a maximum deviation of 0.046 (1 Å for one of the N atoms. The mean plane of the semicarbazone group forms dihedral angles of 33.61 (8 and 39.1 (9° with the benzene ring of the major and minor components, respectively. In the crystal structure, molecules are linked by intermolecular N—H...O hydrogen bonds into extended chains along the c axis. The crystal structure is further stabilized by weak intermolucular C—H...π interactions.

  3. Synthesis, growth of organic nonlinear optical crystal: Semicarbazone of 2-amino-5-chloro-benzophenone (S2A5CB) and its characterisation

    Science.gov (United States)

    Sethuraman, K.; Ramesh Babu, R.; Vijayan, N.; Gopalakrishnan, R.; Ramasamy, P.

    2006-05-01

    A new organic crystal of semicarbazone of 2-amino-5-chloro-benzophenone has been grown as a single crystal by slow evaporation solution growth technique for the first time in the literature. The grown crystal has been characterised by proton nuclear magnetic resonance spectral analysis and single crystal and powder X-ray diffraction studies. Functional groups of the crystallised molecules were confirmed by FT-IR and FT-Raman analyses. Mechanical strength of the crystals was studied by microhardness test. Optical transparency of the grown crystals has been studied by UV-Visible spectra. The second harmonic generation property of the compound was analysed.

  4. SPECTROSCOPIC AND BIOLOGICAL STUDIES OF SOME NEW COORDINATION COMPOUNDS OF TIN (II) AND (IV) WITH SEMICARBAZONES AND THIOSEMICARBAZONES.

    OpenAIRE

    JITENDRA KUMAR RAWAT; HARI SHANKAR YADAV; A.K. VARSHNEY; Varshney, S.

    2012-01-01

    The present paper is a report on the synthesis of some new tin (II) and tin (IV) complexes by the reaction of stannous chloride and dimethyltin dichloride with semicarbazones and thiosemicarbazones using tetrahydrofuran(THF) as reaction medium. Semicarbazones and thiosemicarbazones used in these studies are synthesized by the condensation of 1-acetyl-2-naphthol, 2-acetyl-1-naphathol, 2-acetyl-5-methyl furan, 2-acetyl-4-methyl thiophene and 2-acetyl-naphthalene with ...

  5. A new nano-scale manganese (II) coordination polymer constructed from semicarbazone Schiff base and dicyanamide ligands: Synthesis, crystal structure and DFT calculations

    Science.gov (United States)

    Farhadi, Saeed; Mahmoudi, Farzaneh; Simpson, Jim

    2016-03-01

    A new nano-structured Mn(II) coordination polymer [Mn(HL)(dca)(Cl)]n(1), [HL= Pyridine-2-carbaldehyde semicarbazone, dca= dicyanamide] has been synthesized by a sonochemical method and has been characterized by scanning electron microscopy, X-ray powder diffraction elemental analysis and IR spectroscopy. Single crystals of compound 1 was synthesized by slow evaporation method and was structurally characterised by single crystal X-ray diffraction. The single crystal structure shows one dimensional zig-zag chains with end-to-end dicyanamide-bridged ligand. A distorted octahedral geometry around the Mn2+centers was achieved by NNO atoms from HL, two nitrogen atoms of dicyanamide and one chlorine atom. Also for more details, the structure of 1, has been optimized by density functional theory (DFT calculations).

  6. Synthesis and In Vitro and In Vivo Evaluation of a New 68Ga-Semicarbazone Complex: Potential PET Radiopharmaceutical for Tumor Imaging

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    N. S. Al-Hokbany

    2014-01-01

    Full Text Available In an attempt to develop new tumor imaging radiotracers with favorable biochemical properties, we have synthesized new 68Ga-2-acetylpyridine semicarbazone (68Ga-[APSC]2 as a potential positron emission tomography (PET tumor imaging agent using a straightforward and a one-step simple reaction. Radiochemical yield and purity were quantitative without HPLC purification. Biodistribution studies in nude mice model bearing human MDA-MB-231 cell line xenografts displayed significant tumor uptake of 68Ga-[APSC]2 radiotracer after 2 h postinjection (p.i.. The initial results demonstrate that 68Ga-[APSC]2 radiotracer may be useful probe for detecting and staging of hypoxic tumor using PET imaging modality.

  7. Exploration of a Library of 3,4-(Methylenedioxy)aniline-Derived Semicarbazones as Dual Inhibitors of Monoamine Oxidase and Acetylcholinesterase: Design, Synthesis, and Evaluation.

    Science.gov (United States)

    Tripathi, Rati K P; Rai, Gopal K; Ayyannan, Senthil R

    2016-06-01

    A library of 3,4-(methylenedioxy)aniline-derived semicarbazones was designed, synthesized, and evaluated as monoamine oxidase (MAO) and acetylcholinesterase (AChE) inhibitors for the treatment of neurodegenerative diseases. Most of the new compounds selectively inhibited MAO-B and AChE, with IC50 values in the micro- or nanomolar ranges. Compound 16, 1-(2,6-dichlorobenzylidene)-4-(benzo[1,3]dioxol-5-yl)semicarbazide presented a balanced multifunctional profile of MAO-A (IC50 =4.52±0.032 μm), MAO-B (IC50 =0.059±0.002 μm), and AChE (IC50 =0.0087±0.0002 μm) inhibition without neurotoxicity. Kinetic studies revealed that compound 16 exhibits competitive and reversible inhibition against MAO-A and MAO-B, and mixed-type inhibition against AChE. Molecular docking studies further revealed insight into the possible interactions within the enzyme-inhibitor complexes. The most active compounds were found to interact with the enzymes through hydrogen bonding and hydrophobic interactions. Additionally, in silico molecular properties and ADME properties of the synthesized compounds were calculated to explore their drug-like characteristics. PMID:27135466

  8. Synthesis and Crystal Structure of a Zinc(Ⅱ) Complex Salt with the Schiff Base of Picolinaldehyde N-oxide and Semicarbazone

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The title zinc(Ⅱ) complex salt [Zn(H2O)6](ClO4)2·(PNOS)4, where PNOS is derived from picolinaldehyde N-oxide with semicarbazone, has been prepared and structurally characterized by X-ray single-crystal analysis. It crystallizes in triclinic, space group P1 with a = 7.529(3),b = 10.206(4), c = 14.678(6) A, α = 86.293(6), β = 87.686(7), γ= 81.382(6)°, C28H44Cl2N16O22Zn,Mr = 1093.06, V= 1112.3(8) A3, Z = 1, Dc = 1.632 g/cm3, S = 1.089,μ(MoKα) = 0.773 mm-1 ,F(000) = 564, the final R = 0.0438 and wR = 0.1076 for 3888 independent reflections with Rint =0.0224. The crystal structure possesses a [Zn(H2O)6]2+ cation, two ClO4- anions and four PNOSs.In the crystal structure, Zn2+ cation is located at the symcenter and coordinated by six water molecules. In [Zn(H2O)6]2+, an elongate octahedral complex cation, the average Zn-O bond length is 2.087(2) A. There exist a lot of H bonds in the structure, linking the cation [Zn(H2O)6]2+, anion ClO4-and PNOS to form a 3D network.

  9. Design, synthesis and biological evaluation of novel 4-phenoxy-6,7-disubstituted quinolines possessing (thio)semicarbazones as c-Met kinase inhibitors.

    Science.gov (United States)

    Zhai, Xin; Bao, Guanglong; Wang, Limei; Cheng, Mingke; Zhao, Meng; Zhao, Sijia; Zhou, Hongyang; Gong, Ping

    2016-03-15

    In continuing our efforts to identify small molecules able to inhibit c-Met kinase, three series of novel 6,7-disubstituted-4-phenoxyquinoline derivatives (23a-w, 26a-d and 30a-d) bearing (thio)semicarbazone scaffold were designed, synthesized and evaluated for their cytotoxicity. The biological data revealed that most compounds exhibited moderate-to-excellent activity against HT-29, MKN-45, A549 cancer cell lines and relative poor potency toward MDA-MB-231 cell as well as hardly any cytotoxicity in normal PBL cell. Eleven compounds were further examined for their inhibitory activity against c-Met kinase and three compounds (23h, 23n and 26a) demonstrated good inhibitory activity. This work resulted in the discovery of a potent c-Met inhibitor 23n, bearing 2-hydroxy-3-allylphenyl group at R(2) moiety, as a valuable lead molecule, which possessed remarkable cytotoxicity and high selectivity against A549 and HT-29 cell lines with IC50 values of 11 nM and 27 nM. Besides, it displayed excellent c-Met kinase inhibition on a single-digital nanomolar level (IC50=1.54 nM). Meanwhile, the results from preliminarily in vivo study reflected that compound 23n showed promising overall PK profiles, consistent with the efficacy in both MKN-45 and HT-29 tumor xenograft mice model. These results clearly indicated that compound 23n is a potent and highly selective c-Met inhibitor and its favorable in vitro and in vivo profiles warrant further investigation. PMID:26897090

  10. Synthesis, spectroscopic (FT-IR, FT-Raman, UV and NMR) and computational studies on 3t-pentyl-2r,6c-diphenylpiperidin-4-one semicarbazone

    Science.gov (United States)

    Arockia doss, M.; Savithiri, S.; Rajarajan, G.; Thanikachalam, V.; Saleem, H.

    2015-09-01

    The structural and spectroscopic studies of 3t-pentyl-2r,6c-diphenylpiperidin-4-one semicarbazone (PDPOSC) were made by adopting B3LYP/HF levels theory using 6-311++G(d,p) basis set. The FT-IR and Raman spectra were recorded in solid phase, the fundamental vibrations were assigned on the basis of the total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method and PQS program. DFT method indicates that B3LYP is superior to HF method for molecular vibrational analysis. UV-vis spectrum of the compound was recorded in different solvents in the region of 200-800 nm and the electronic properties such as excitation energies, oscillator strength, wavelengths, HOMO and LUMO energies were evaluated by time-dependent DFT (TD-DFT) approach. The polarizability and first order hyperpolarizability of the title molecule were calculated and interpreted. The hyperconjugative interaction energy (E(2)) and electron densities of donor (i) and acceptor (j) bonds were calculated using NBO analysis. In addition, MEP and atomic charges of carbon, nitrogen and oxygen were calculated using B3LYP/6-311++G(d,p) level theory. Moreover, thermodynamic properties of the title compound were calculated by B3LYP/HF, levels using 6-311++G(d,p) basis set. The 1H and 13C nuclear magnetic resonance (NMR) chemical shifts of the molecule were calculated by the gauge independent atomic orbital (GIAO) method and compared with experimental results.

  11. 乙酰基二茂铁缩氨脲的合成及其电化学性质%Synthesis and electrochemical properties of acetylferrocene semicarbazone

    Institute of Scientific and Technical Information of China (English)

    吴校彬

    2012-01-01

    Acetylferrocene aemicarbazone ( AFS) was synthesized from ferrocene. The structure of the semicarbazone was confirmed by IR, 'HNMR and elementary analysis. The electrochemical properties of AFS in anhydrous acetonitrile solution were investigated by CV( cyclic voltammetry) . The result showed that a pair of redox wave appeared in the rang of -0. 1 ~0. 83 V. When scan rate is between 100 mV/s to 500 mV/s, the half-wave potential (E1/2) is 0. 476 - 0. 466 V, and the ratio of /pa and Ipc is 1. 387 - 1. 269 and the peak current (/Ip) has fine liner relationship with the square root of scan rate(v1/2).%以二茂铁为原料通过两步反应合成了标题化合物,其结构通过IR、1HNMR和元素分析予以确证.采用循环伏安法测定了该化合物在无水乙腈溶液中的电化学性能.实验结果表明,在扫描范围(-0.1~0.83 V)内,标题化合物出现了一对氧化还原峰;当扫描速度在100~500 mV/s范围时,其半波电位(E1/2)为0.476 ~0.466 V;峰电流比(Ipa/Ipc)为1.387~1.269,并且峰电流(Ip)与扫描速度平方根(v1/2)呈良好的线性关系.

  12. Synthesis, and molecular sensing behavior of fac-[Re(CO)3(κ2-N,N-dpksc)Cl], dpksc = di-2-pyridyl ketone semicarbazone

    Science.gov (United States)

    Bakir, Mohammed; Brown, Ordel

    2013-01-01

    When [Re(CO)5Cl] was allowed to react with di-2-pyridyl ketone semicarbazone hydrochloride (dpksc.HCl) in refluxing toluene, fac-[Re(CO)3(κ2-N,N-dpksc)Cl] was isolated. The identity of fac-[Re(CO)3(κ2-N,N-dpksc)Cl] was elucidated from the results of its elemental analysis and confirmed using a number of spectroscopic measurements. Spectroscopic measurements done on non-aqueous solvents divulged sensitivity of fac-[Re(CO)3(κ2-N,N-dpksc)Cl] to changes in its surroundings. 1H NMR studies revealed significant solvent dependence as manifested by the chemical shift variations; the exchange of the amine protons with solvent deuterium in CDCl3 and d6-acetone; the temperature dependence of the chemical shifts of the amine and amide protons and insignificant temperature dependence of the aromatic proton. The electronic absorption spectra of fac-[Re(CO)3(κ2-N,N-dpksc)Cl] measured on non-aqueous solvents disclosed two high energy intra-ligand charge transfer (ILCT) transitions. Optical measurements performed on protophilic solutions of fac-[Re(CO)3(κ2-N,N-dpksc)Cl] in the presence of bases and acids showed the appearance and disappearance of a low energy ILCT electronic transitions and established reversible inter-conversion between fac-[Re(CO)3(κ2-N,N-dpksc)Cl] and its conjugate base, fac-[Re(CO)3(κ2-N,N-dpksc-H)Cl]-. Thermo-optical measurements done on protophilic solutions of fac-[Re(CO)3(κ2-N,N-dpksc)Cl] disclosed the absence of thermal acid-base inter-conversion between fac-[Re(CO)3(κ2-N,N-dpksc)Cl] and fac-[Re(CO)3(κ2-N,N-dpksc-H)Cl]- and established reversible electronic transfer between the high energy electronic transitions of fac-[Re(CO)3(κ2-N,N-dpksc)Cl]. Optosensing measurements done on protophilic solutions of fac-[Re(CO)3(κ2-N,N-dpksc)Cl] showed acids and bases in concentrations as low as 1.00 × 10-10 M can be detected and determined using protophilic solutions of of fac-[Re(CO)3(κ2-N,N-dpksc)Cl]. Electrochemical measurements on dmf solutions of fac

  13. Crystal structure of 4-formylpyridine semicarbazone hemihydrate

    Directory of Open Access Journals (Sweden)

    Mayara Hissami Inoue

    2015-05-01

    Full Text Available The molecule of the title compound C7H8N4O·0.5H2O, alternatively called (E-1-(pyridin-4-ylmethylenesemicarbazide hemihydrate, is in the E conformation and is almost planar; the r.m.s. deviation of the positions of the atoms of the pyridine ring from the best-fit plane is 0.0039 Å. The C, N and O atoms of the rest of the molecule sits close on this plane with a largest deviation of 0.115 (4 Å for the O atom of the semicarbazone moiety. There is an intramolecular N—H...N hydrogen bond. In the crystal, molecules are linked into an infinite three-dimensional network by classical N—H...Os (s = semicarbazone and Ow—H...N (w = water hydrogen bonds.

  14. Ligational behavior of thiosemicarbazone, semicarbazone and thiocarbohydrazone ligands towards VO(IV), Ce(III), Th(IV) and UO 2(VI) ions: Synthesis, structural characterization and biological studies

    Science.gov (United States)

    Shebl, M.; Seleem, H. S.; El-Shetary, B. A.

    2010-01-01

    Mono- and binuclear VO(IV), Ce(III), Th(IV) and UO 2(VI) complexes of thiosemicarbazone, semicarbazone and thiocarbohydrazone ligands derived from 4,6-diacetylresorcinol were synthesized. The structures of these complexes were elucidated by elemental analyses, IR, UV-vis, ESR, 1H NMR and mass spectra as well as conductivity and magnetic susceptibility measurements and thermal analyses. The thiosemicarbazone (H 4L 1) and the semicarbazone (H 4L 2) ligands behave as dibasic pentadentate ligands in case of VO(IV) and UO 2(VI) complexes, tribasic pentadentate in case of Ce(III) complexes and monobasic pentadentate in case of Th(IV) complexes. However, the thiocarbohydrazone ligand (H 3L 3) acts as a monobasic tridentate ligand in all complexes except the VO(IV) complex in which it acts as a dibasic tridentate ligand. The antibacterial and antifungal activities were also tested against Rhizobium bacteria and Fusarium-Oxysporium fungus. The metal complexes of H 4L 1 ligand showed a higher antibacterial effect than the free ligand while the other ligands (H 4L 2 and H 3L 3) showed a higher effect than their metal complexes. The antifungal effect of all metal complexes is lower than the free ligands.

  15. (E)-4-Octyloxybenzaldehyde thio­semicarbazone

    OpenAIRE

    2009-01-01

    In the title compound, C16H25N3OS, the thio­semicarbazone group adopts an E configuration with respect to the C=N bond and is almost coplanar with the benzene ring, forming a dihedral angle of 9.3 (1)°. In the crystal packing, the mol­ecules lie along the a axis in an anti­parallel arrangement and are held in place by van der Waals inter­actions. As a consequence, there is relatively low anisotropic thermal motion in the terminal atoms of the n-octyl chain.

  16. Growth of semicarbazone of benzophenone single crystals

    Science.gov (United States)

    Vijayan, N.; Ramesh Babu, R.; Gopalakrishnan, R.; Dhanuskodi, S.; Ramasamy, P.

    2002-03-01

    Semicarbazone of benzophenone single crystals have been grown by slow evaporation solution growth technique. The grown crystals have been characterized using XRD, melting point, FT-IR and UV-Vis spectra analyses. The X-ray diffraction analysis reveals that the crystal belongs to the triclinic crystal system and space group P1. From FT-IR studies it is found that the compound possesses both free and hydrogen bonded N-H stretching modes. The hydrogen bonded N-H stretching mode is found to be the major driving force for packing of molecules in the crystals. The transparency of the grown crystals has been confirmed using UV-Vis spectra.

  17. (E-1-(4-Chlorophenylethanone semicarbazone

    Directory of Open Access Journals (Sweden)

    Hoong-Kun Fun

    2009-07-01

    Full Text Available In the title compound, C9H10ClN3O, the semicarbazone group is approximately planar, with an r.m.s. deviation from the mean plane of 0.054 (1 Å. The dihedral angle between the least-squares planes through the semicarbazone group and the benzene ring is 30.46 (5°. In the solid state, molecules are linked via intermolecular N—H...O and N—H...N hydrogen bonds, generating R22(9 ring motifs which, together with R22(8 ring motifs formed by pairs of intermolecular N—H...O hydrogen bonds, lead to the formation of a seldom-observed molecular trimer. Furthermore, N—H...O hydrogen bonds form R21(7 ring motifs with C—H...O hydrogen bonds, further consolidating the crystal structure. Molecules are linked by these intermolecular interactions, forming two-dimensional networks parallel to (100.

  18. 新取代冠醚及其缩氨硫脲和缩氨脲化合物的合成%Synthesis of New Substituted Crown Ether and Its Concentrated Aminothiourea and Semicarbazone Compounds

    Institute of Scientific and Technical Information of China (English)

    张来新; 杨琼

    2001-01-01

    Indanone-〔1〕-5, 6-benzo-15-crown-5 has been sythesized by acylation in polyphosphoric acid (PPA) ,it was then reacted with thiosemicarbazide and semicarbazide under acid condition to give indanone〔1〕-thiosemicarbazone and semicarbazone-5,6-benzo-15-crown-5. The three new products were characterized by elemental analysis ,IR and mass spectrometry.%报道了在多聚磷酸中将冠醚酰化的方法,合了茚满酮-〔1〕-5,6-苯并-15-冠-5.以此为原料,在酸性条件下,与氨基硫脲和氨基脲作用,合成了茚满酮-〔1〕-缩氨基硫脲和缩氨基脲-5,6-苯并-15-冠-5.经由IR,MS和元素分析对合成的三种新物质的结构进行了鉴定.

  19. 稠环缩氨基脲衍生物的合成与杀虫活性%Synthesis of Condensed-Cyclic Semicarbazone Derivatives and Their Insecticidal Activity

    Institute of Scientific and Technical Information of China (English)

    周宇涵; 龚润军; 苗蔚荣; 曲景平

    2013-01-01

    以4-氯苯乙酸为原料,经环化、氧化、缩合、加氢、酰化反应合成了6个新的具有茚结构的稠环缩氨基脲衍生物,总收率7% ~9%.其结构经核磁共振氢谱和高分辨质谱确认正确.初步生物活性测试表明:大多数化合物对多种害虫具有很好的杀虫活性.7-氯-2,3,4a,5-四氢-2-[N-甲氧羰基-N-(4-三氟甲基苯基)氨基甲酰基]茚戊[1,2-e][1,3,4]噁二嗪-4a-甲酸甲酯(Ⅻb)的活性略高于已商品化杀虫剂茚虫威.%Several new aromatic condensed-cyclic semicarbazone derivatives with the structure of indene were prepared from 4-chlorophenylacetic acid in 7% ~9% yield, through cyclization, oxidation, condensation, hydrogenation, acylation, etc. Their structures were confirmed through HNMR and HRMS. Preliminary bioassay shows that most of them exhibited good activity toward various insects. Methyl 7-chloro-2,5-dihydro-2-[ [ ( methoxycarbonyl) [ 4-( trifluoromethyl) -phenyl ] amino ] carbonyl ] indeno[ 1, 2-e ] [ 1, 3 , 4 ] oxadiazine-4a ( 3H)-carboxylate (Ⅻb) even shows higher activity than Indoxacarb.

  20. Anti-inflammatory and analgesic activities of acetophenone semicarbazone and benzophenone semicarbazone

    Institute of Scientific and Technical Information of China (English)

    Shaikh M Mohsin Ali; Mele Jesmin; M Abul Kalam Azad; M Khairul Islam; Ronok Zahan

    2012-01-01

    Objective: To study anti-inflammatory and analgesic activities in swiss albino mice, two schiff bases namely acetophenone semicarbazone (ASC) and benzophenone semicarbazone (BSC) were synthesized and characterized. Methods: Two doses of the test compounds 25 and 50 mg/kg (p.o) for each were selected throughout the research work. The anti-inflammatory activity of the test compounds was determined by ‘carragenan induced mice paw edema inhibition’ method. The analgesic activity was determined by both, ‘acetic acid induced writhing’ and ‘tail immersion' methods. All such data were compared with standard drugs at the dose of 10 mg/kg (p.o.). Results:Both ASC and BSC have showed positive effects as anti-inflammatory and analgesic agents. Anti-inflammatory and analgesic activities of the test compounds at 50 mg/kg (p.o.) were quite comparable to those of standard drugs at 10 mg/kg (p.o.). Conclusion: Both ASC and BSC can be considered as potent anti-inflammatory and analgesic agents.

  1. (E-1-(4-Fluorophenylethan-1-one semicarbazone

    Directory of Open Access Journals (Sweden)

    Hoong-Kun Fun

    2009-07-01

    Full Text Available In the title compound, C9H10FN3O, the semicarbazone group is nearly planar, with the maximum deviation of 0.044 (1 Å for one of the N atoms. The mean plane of semicarbazone group forms a dihedral angle of 30.94 (4° with the benzene ring. The molecules are linked into a supramolecular chain by N—H...O hydrogen bonds formed along the c axis. The crystal structure is further stabilized by weak intermolucular C—H...π interactions; the closest C...Cg contact is 3.6505 (11 Å.

  2. (1Z-1-(2,4-Dichlorophenylethan-1-one semicarbazone

    Directory of Open Access Journals (Sweden)

    Hoong-Kun Fun

    2009-09-01

    Full Text Available In the title compound, C9H9Cl2N3O, the semicarbazone group is approximately planar, with an r.m.s deviation from the mean plane of 0.011 (2 Å. The dihedral angle between the least-squares planes through the semicarbazone group and the benzene ring is 38.76 (9°. The crystal structure is further stabilized by N—H...O and C—H...O hydrogen bonding.

  3. In vivo anticancer activity of vanillin semicarbazone

    Institute of Scientific and Technical Information of China (English)

    Shaikh M Mohsin Ali; M Abul Kalam Azad; Mele Jesmin; Shamim Ahsan; M Mijanur Rahman; Jahan Ara Khanam; M Nazrul Islam; Sha M Shahan Shahriar

    2012-01-01

    Objective:To evaluate the anticancer activity of vanillin semicarbazone (VSC) against Ehrlich ascites carcinoma (EAC) cells in Swiss albino mice. Methods:The compound VSC at three doses (5, 7.5 and 10 mg/kg i.p.) was administered into the intraperitoneal cavity of the EAC inoculated mice to observe its efficiency by studying the cell growth inhibition, reduction of tumour weight, enhancement of survival time as well as the changes in depleted hematological parameters. All such parameters were also studied with a known standard drug bleomycin at the dose of 0.3 mg/kg (i.p.). Results:Among the doses studied, 10 mg/kg (i.p.) was found to be quite comparable in potency to that of bleomycin at the dose of 0.3 mg/kg (i.p.). The host toxic effects of VSC was found to be negligible. Conclusions: It can be concluded that VSC can therefore be considered as potent anticancer agent.

  4. Growth and characterisation of benzaldehyde semicarbazone (BSC) single crystals

    Science.gov (United States)

    Ramesh Babu, R.; Vijayan, N.; Gopalakrishnan, R.; Ramasamy, P.

    2002-05-01

    Single crystals of potential organic nonlinear optical materials of Benzaldehyde Semicarbazone (BSC) were grown by slow evaporation technique. The grown crystals were identified by X-ray diffraction method. The functional groups were identified from FT-IR spectrum. UV-visible and thermal gravimetric analyses were made.

  5. P-Dimethylaminobenzaldehyde semicarbazone: The bonding abilities of imine nitrogen atom

    Science.gov (United States)

    Trzesowska, Agata

    2009-01-01

    The crystal and molecular structures of p-dimethylaminobenzaldehyde semicarbazone and p-dimethylaminobenzaldehyde semicarbazone hydrochloride have been determined. On the basis of quantum-mechanical calculations the availability of the imine nitrogen atom for bonding with molecular species was analysed and also the complete assignment of the experimental IR spectrum was performed. The p-dimethylaminobenzaldehyde semicarbazone was characterised by thermogravimetric analysis in conjunction with evolved gases in the air atmosphere.

  6. Antifungal activities of thiosemicarbazones and semicarbazones against mycotoxigenic fungi

    Directory of Open Access Journals (Sweden)

    Rojane de Oliveira Paiva

    2014-12-01

    Full Text Available Mycotoxigenic fungi can compromise the quality of food, exposing human and animal health at risk. The antifungal activity of eight thiosemicarbazones (1-8 and nine semicarbazones (9-17 was evaluated against Aspergillus flavus, A. nomius, A. ochraceus, A. parasiticus and Fusarium verticillioides. Thiosemicarbazones had MIC values of 125-500 µg/ml. The thiosemicarbazones 1 and 2 exerted fungistatic activity against Aspergillus spp., and thiosemicarbazone 2 exerted fungicidal activity against F. verticillioides. Compound 2 showed an iron chelating effect of 63%. The ergosterol content of A. parasiticus had a decrease of 28 and 71% for the 31.2 and 62.5 µg/ml concentrations of thiosemicarbazone 2 compared to the control. The obtained results of antifungal activity revealed that thiosemicarbazone class was more active when compared to semicarbazone class and, the thiosemicarbazone 2 was the most active compound, specially, against Aspergillus spp.

  7. DFT (B3LYP COMPUTATIONAL STUDY ON THE MECHANISMS OF FORMATION OF SOME SEMICARBAZONES

    Directory of Open Access Journals (Sweden)

    Abdulfatai Siaka

    2016-06-01

    Full Text Available Thermodynamic and kinetic mechanisms of forming six semicarbazones have been investigated computationally by DFT B3LYP method. All the reactions proceed via two transitions and include two consecutive steps: bimolecular and unimolecular. The computed transition steps have varying equilibrium constants values, enthalpy of activation and Gibbs energy of activation, depending on the semicarbazone involved.

  8. Some lanthanide complexes of semicarbazone and thiosemicarbazone derived from fluorenone

    International Nuclear Information System (INIS)

    A new series of lanthanide chloride complexes with the ligands fluorenone semicarbazone (FSC) and fluorenone thiosemicarbazone (FTSC) of composition [LnLCl2(H2O)2](Ln = La, Pr, Nd, Sm, Gd) were synthesised and characterized by microanalytical, spectral, magnetic and conductivity data. These ligands act as monovalent bidentate and bond through carbonyl oxygen/thiocarbonyl sulfur and the azomethine nitrogen atom. (author). 18 refs., 2 tabs

  9. Intramolecular cyclization of steroidal semicarbazones to pyrazoles using Vilsmeier reagent

    Institute of Scientific and Technical Information of China (English)

    Mahboob Alam; M.Mushfiq

    2008-01-01

    The preparation of hitherto unknown steroidal heterocycles containing pyrazole fused to 6,7-position of the steroidal nucleus is described.These heterocycles were prepared by the action of Vilsmeier reagent with steroidal semicarbazones in DMF.The slructure of the compounds has been established on the basis of their elemental analysis and spectral data.A general mechanistic scheme for these reactions is also suggested based on current and previous results.

  10. Spectral studies of semicarbazones derived from 3- and 4-formylpyridine and 3- and 4-acetylpyridine: crystal and molecular structure of 3-formylpyridine semicarbazone

    Science.gov (United States)

    Beraldo, Heloisa; Nacif, Wanderlene F.; West, Douglas X.

    2001-08-01

    Semicarbazones derived from 3- and 4-formylpyridine (H3FoPyS, H4FoPyS) and 3- and 4-acetylpyridine (H3AcPyS, H4AcPyS) were prepared and studied spectroscopically. Complete NMR assignments for these semicarbazones were made using DEPT135, as well as HMQC and HMBC heteronuclear correlation techniques. The crystal and molecular structures of H3FoPyS were determined.

  11. Crystal structure of 4-formyl­pyridine semicarbazone hemihydrate

    Science.gov (United States)

    Inoue, Mayara Hissami; Back, Davi F.; Burrow, Robert A.; Nunes, Fábio Souza

    2015-01-01

    The mol­ecule of the title compound C7H8N4O·0.5H2O, alternatively called (E)-1-(pyridin-4-yl­methyl­ene)semi­carb­azide hemihydrate, is in the E conformation and is almost planar; the r.m.s. deviation of the positions of the atoms of the pyridine ring from the best-fit plane is 0.0039 Å. The C, N and O atoms of the rest of the mol­ecule sits close on this plane with a largest deviation of 0.115 (4) Å for the O atom of the semicarbazone moiety. There is an intra­molecular N—H⋯N hydrogen bond. In the crystal, mol­ecules are linked into an infinite three-dimensional network by classical N—H⋯Os (s = semicarbazone) and Ow—H⋯N (w = water) hydrogen bonds. PMID:25995925

  12. The antimicrobial activity of lapachol and its thiosemicarbazone and semicarbazone derivatives

    OpenAIRE

    Marina Azevedo Souza; Susana Johann; Luciana Alves Rodrigues dos Santos Lima; Fernanda Fraga Campos; Isolda Castro Mendes; Heloisa Beraldo; Elaine Maria de Souza-Fagundes; Patricia Silva Cisalpino; Carlos Augusto Rosa; Tania Maria de Almeida Alves; Nivea Pereira de Sa; Carlos Leomar Zani

    2013-01-01

    Lapachol was chemically modified to obtain its thiosemicarbazone and semicarbazone derivatives. These compounds were tested for antimicrobial activity against several bacteria and fungi by the broth microdilution method. The thiosemicarbazone and semicarbazone derivatives of lapachol exhibited antimicrobial activity against the bacteria Enterococcus faecalis and Staphylococcus aureus with minimal inhibitory concentrations (MICs) of 0.05 and 0.10 µmol/mL, respectively. The thiosemicarbazone an...

  13. The antimicrobial activity of lapachol and its thiosemicarbazone and semicarbazone derivatives

    OpenAIRE

    2013-01-01

    Lapachol was chemically modified to obtain its thiosemicarbazone and semicarbazone derivatives. These compounds were tested for antimicrobial activity against several bacteria and fungi by the broth microdilution method. The thiosemicarbazone and semicarbazone derivatives of lapachol exhibited antimicrobial activity against the bacteria Enterococcus faecalis and Staphylococcus aureus with minimal inhibitory concentrations (MICs) of 0.05 and 0.10 µmol/mL, respectively. The thiosemicarbazo...

  14. Synthesis and Evaluation of Antioxidant Activity of Semicarbazone Derivatives

    Directory of Open Access Journals (Sweden)

    Manmohan Singhal

    2011-04-01

    Full Text Available In present study, a series of chalconesemicarbazones was synthesized and evaluated for antioxidant activity by DPPH free radical scavenging assay. Most of the compounds were found to be potent antioxidant. Free radicals play an important role in various pathological and xenotoxic effects so antioxidant may have protective role in these pathological conditions. Based on the results of an anti-oxidant study, Compound 23 was the most active compound. The highest scavenger activity observed in compound 23 is probably due to the presence of hydroxyl group in the acetophenic moiety and methoxy group in aldehydic moiety of chalcone. It was found that methoxy and hydroxyl substituted chalconesemicarbazones were potent nitric oxide scavenger and unsubstituted compound showed very less activity.

  15. Synthesis and reducing power assay of methyl semicarbazone derivatives

    Directory of Open Access Journals (Sweden)

    Manmohan Singhal

    2014-04-01

    Full Text Available In the present study we have designed a new pharmacophore ‘Chalconesemicarbazone’ by pharmacophore hybridization approach of drug design. A series of novel chalconesemicarbazones was synthesized and evaluated for their antioxidant activity by reducing power assay. Most of the compounds were found to be potent antioxidants. Free radicals play an important role in various pathological and xenotoxic effects so antioxidant may have protective role in these pathological conditions. Based on the results of reducing power assay 1-[1-(2,4-dihydroxyphenyl-3-(2-hydroxyphenylallylidene]-4-(4-methylphenylsemicarbazide (compound 18 and 1-[1-(2,5-dihydroxyphenyl-3-(6-hydroxyphenylallylidene]-4-(4-methylphenylsemicarbazide (compound 21 were the most active lead compounds. It was found that methoxy and hydroxyl substituted chalconesemicarbazones exhibited potent reducing power and unsubstituted compound showed less reducing potential.

  16. Synthesis and Antibacterial Activity of Novel Hydroxy Semicarbazone Derivatives

    NARCIS (Netherlands)

    Hariri, Elham; Mahboubi, Arash; Rahmani, Parisa; Hajmohammadebrahimtehrani, K.; Babaeian, Mohammad; Mashayekhi, V.; Kobarfard, Farzad

    2016-01-01

    A series of hydroxysemicarbazone derivatives of substituted diaryl ketones and acetophenones were synthesized and their structures were confirmed by analytical and spectroscopic methods including elemental analysis, infrared and nuclear magnetic resonance spectroscopy. The derivatives were prepared

  17. Semicarbazone EGA Inhibits Uptake of Diphtheria Toxin into Human Cells and Protects Cells from Intoxication

    Science.gov (United States)

    Schnell, Leonie; Mittler, Ann-Katrin; Mattarei, Andrea; Tehran, Domenico Azarnia; Montecucco, Cesare; Barth, Holger

    2016-01-01

    Diphtheria toxin is a single-chain protein toxin that invades human cells by receptor-mediated endocytosis. In acidic endosomes, its translocation domain inserts into endosomal membranes and facilitates the transport of the catalytic domain (DTA) from endosomal lumen into the host cell cytosol. Here, DTA ADP-ribosylates elongation factor 2 inhibits protein synthesis and leads to cell death. The compound 4-bromobenzaldehyde N-(2,6-dimethylphenyl)semicarbazone (EGA) has been previously shown to protect cells from various bacterial protein toxins which deliver their enzymatic subunits from acidic endosomes to the cytosol, including Bacillus anthracis lethal toxin and the binary clostridial actin ADP-ribosylating toxins C2, iota and Clostridium difficile binary toxin (CDT). Here, we demonstrate that EGA also protects human cells from diphtheria toxin by inhibiting the pH-dependent translocation of DTA across cell membranes. The results suggest that EGA might serve for treatment and/or prevention of the severe disease diphtheria. PMID:27428999

  18. Semicarbazone EGA Inhibits Uptake of Diphtheria Toxin into Human Cells and Protects Cells Articlefrom Intoxication.

    Science.gov (United States)

    Schnell, Leonie; Mittler, Ann-Katrin; Mattarei, Andrea; Tehran, Domenico Azarnia; Montecucco, Cesare; Barth, Holger

    2016-01-01

    Diphtheria toxin is a single-chain protein toxin that invades human cells by receptor-mediated endocytosis. In acidic endosomes, its translocation domain inserts into endosomal membranes and facilitates the transport of the catalytic domain (DTA) from endosomal lumen into the host cell cytosol. Here, DTA ADP-ribosylates elongation factor 2 inhibits protein synthesis and leads to cell death. The compound 4-bromobenzaldehyde N-(2,6-dimethylphenyl)semicarbazone (EGA) has been previously shown to protect cells from various bacterial protein toxins which deliver their enzymatic subunits from acidic endosomes to the cytosol, including Bacillus anthracis lethal toxin and the binary clostridial actin ADP-ribosylating toxins C2, iota and Clostridium difficile binary toxin (CDT). Here, we demonstrate that EGA also protects human cells from diphtheria toxin by inhibiting the pH-dependent translocation of DTA across cell membranes. The results suggest that EGA might serve for treatment and/or prevention of the severe disease diphtheria. PMID:27428999

  19. 环庚酮缩氨基脲与Cu(Ⅱ)、Fe(Ⅱ)、Zn(Ⅱ)配合物的直接电化学合成%Direct electrochemical synthesis of Cu(Ⅱ) ,Fe(Ⅱ),Zn(Ⅱ) complexes of cycloheptanone semicarbazone

    Institute of Scientific and Technical Information of China (English)

    仵博万; 刘建宁; 李惠成; 康敬万

    2001-01-01

    在以环庚酮缩氨基脲为配体 的非水溶剂中,用Cu、Fe、Zn金属做阳极,用电化学金属阳极氧化法合 成了环庚酮缩氨基脲与Cu(Ⅱ)、Fe(Ⅱ)、 Zn(Ⅱ)的金属配合物,通过元素分析、红外光谱、紫外光谱、摩尔电导等对配合物进行了表征.%Cu(Ⅱ),Fe(Ⅱ), Zn(Ⅱ)complexes of cycloheptanone semicarbazone are synthesiz ed by the electrochemical oxidation of anodic metal into nonaqueous solvent.The complexes are characterized by elemental analysis,IR,UV and molar conductivity.

  20. 2-羟基-1-萘甲醛半碳酰腙铬(Ⅲ)配合物的合成和晶体结构%Synthesis and Crystal Structure of the Chromium(Ⅲ) Complex with 2-hydro-l-naphthaldehyde Semicarbazone

    Institute of Scientific and Technical Information of China (English)

    李桂琴; 周荫庄; 肖岭梅; 朱惠菊; 屠淑洁

    2008-01-01

    The mononuclear chromium(Ⅲ) complex with 2-hydroxy-1-naphthaldehyde semicarbazone was synthesized and characterized by IR, UV-Vis, fluorescence spectra and single-crystal structure determination. The crystal structure belongs to monoclinic system, space group C2/c with a=3.535 7(8) nm, b=1.608 5(4) nm, c=0.930 52(19) nm,β=98.271(4)°, and Z=8. The crystal structure and spectra data suggest that the ligand of 2-hydro-1-naphthal-dehyde semicarbazone behaves as a tridentate chelating agent, coordinating through phenolic oxygen, nitrogen atom of C=N group and ketonic oxygen. The chromium (Ⅲ) center is a six-coordinated distorted octahedral geometry. CCDC: 647892.%本文合成了2-羟基-1-萘甲醛半碳酰腙铬(Ⅲ)单核配合物,通过红外、紫外、荧光光谱和单晶X-射线衍射等方法对其结构进行了表征.其晶体结构属于单斜晶系,空间群C2/c.光谱数据表明:配体2-羟基-1-萘甲醛半碳酰腙作为三齿螯合剂,通过酚氧,亚胺基氮和酮氧与铬(Ⅲ)离子配位.其铬(Ⅲ)中心为扭曲的六配位八面体几何构型.

  1. Design, synthesis and antifungal activity of 8-fluoro-2,3-dihydroquinoline-4 (1H) -one semicarbazone derivatives%8-氟-2,3-二氢喹啉-4(1H)-酮缩氨基脲类化合物的设计、合成及抗真菌活性研究

    Institute of Scientific and Technical Information of China (English)

    原静; 骆伟; 张欣; 田野; 王伟; 苏昕; 郭春

    2012-01-01

    In recent years, the incidence of fungal infections has reached alarming proportions, and the latest market outlook from data monitor shows that the rate of invasive fungal infection is increasingly rising specially. So it is of great significance to develop more effective and safer antifungal agents with novel mechanism of action. The target compounds were designed based on the bioisosterism and combination principle in drug design,to substitute the sulphur atom of thiochromanones with nitrogen giving the 2,3-dihydroquinolin-4(l#)-one scaffold and combine this moiety with semicarbazones which is the pharmacophore of cysteine protease inhibitors to give the scaffold of 2,3-dihydroquinolin-4(l//)-one semicarbazone. Totally sixteen 8-fluoro-2,3-dihydroquinoline-4 (lH)-one semicarbazone derivatives were synthesized and their structures were confirmed by MS and 'H-NMR. The antifungal assay was carried out in vitro by two-fold dilution method, with fluoconazole and itraconazole as the control drugs. The result showed that all the compounds displayed antifungal activities against the tested fungi,Rh,T. R,As,M. G,T. V,C. N,R. R,and C. A,in different levels,of which I,, I6, I7, Iu ,and I14 showed better activity. The preliminary structure activity relationship was summarized.%目的 合成一系列8-氟-2,3-二氢喹啉-4(1H)-酮缩氨基脲类化合物,测定其体外抗真菌活性.方法 以邻氟苯胺为起始原料,经与丙烯酸加成、在多聚磷酸(PPA)中环合制得中间体8-氟-2,3-二氢喹啉4(1H) -酮;该中间体与各种N4-取代的氨基脲缩合得到目标化合物.采用二倍浓度稀释法测试各目标化合物的体外抗真菌活性,实验选用8种临床上常用的致病真菌为测试菌株,以氟康唑、伊曲康唑为阳性对照药.结果与结论 16个8-氟-2,3-二氢喹啉-4(1H)-酮缩氨基脲类化合物均未见文献报道,其结构经1H-NMR、MS谱确证;活性测试结果表明,合成的多个目标化合物对测试真菌

  2. 2,3-二氢喹啉4(1H)-酮缩氨基脲类化合物的设计、合成及抗真菌活性研究%Design, synthesis and evaluation of antifungal activity of 2,3-dihydroquinoline-4 (1H)-one semicarbazone derivatives

    Institute of Scientific and Technical Information of China (English)

    梁振; 孙寰宇; 李传玲; 韩晓丹; 宋培鲁; 苏昕; 郭春

    2013-01-01

    In recent years,the incidence of fungal infections has reached alarming proportions,and the latest market outlook from data monitor shows that the rate of invasive fungal infection is increasingly rising specially. So it is of great significance to develop more effective and safe antifungal agents with novel mechanism of action. The target compounds were designed based on the bioisosterism and combination principle in drug design,by substituting the sulphur atom of thiochromanones with nitrogen giving the 2,3-dihydroquino-lin-4( 1H)-one scaffold and combine this moiety with semicarbazones which is the pharmacophore of cyste-ine protease inhibitors to give the scaffold of 2,3-dihydroquinolin-4(1H)-one semicarbazone. Totally twenty-four 2,3-dihydroquinoline-4 (1H) -one semicarbazone derivatives were synthesized and their structures were confirmed by MS and 1H-NMR. The antifungal assay was carried out in vitro by two-fold dilution method, with fluoconazole as the control drug. The result showed that all the compounds displayed antifungal activities against the tested fungi, T. rubrum, C. albicans, M. gypseum,A. fumigatus, C. neoformans, R. rubra,T. verrucosum,Rhizopus and Aspergillus,in different levels,some of which showed better activities.The preliminary structure activity relationships were summarized.%目的 合成一系列二氯-2,3-二氢喹啉4(1H)-酮缩氨基脲类化合物并测定其体外抗真菌活性.方法 以二氯苯胺和丙烯酸为起始原料,经加成、环合制得中间体5,7-二.氯-2,3-二氢喹啉-4(1H)-酮和6,8-二氯-2,3-二氢喹啉-4(1H)-酮;中间体与各种N4-取代的氨基脲缩合得到目标化合物;采用二倍浓度稀释法测试各目标化合物的体外抗真菌活性,实验选用9种临床上常见的致病真菌为测试菌株,以氟康唑为阳性对照药.结果与结论 合成的24个化合物均未见文献报道,其结构经1H-NMR、MS谱确证;活性测试结果表明,多个目标化合物对测试真菌

  3. EPR, mass, IR, electronic, and magnetic studies on copper(II) complexes of semicarbazones and thiosemicarbazones

    Science.gov (United States)

    Chandra, Sulekh; Gupta, Lokesh Kumar

    2005-01-01

    Copper(II) complexes having the general composition Cu(L) 2X 2 [where L = isopropyl methyl ketone semicarbazone (LLA), isopropyl methyl ketone thiosemicarbazone (LLB), 4-aminoacetophenone semicarbazone (LLC), and 4-aminoacetophenone thiosemicarbazone (LLD) and X = Cl -, 1/2SO 42-] have been synthesized. All the Cu(II) complexes reported here have been characterized by elemental analyses, molar conductance, magnetic moment susceptibility, EI mass, 1H NMR, IR, EPR, and electronic spectral studies. All the complexes were found to have magnetic moments corresponding to one unpaired electrons. The possible geometries of the complexes were assigned on the basis of EPR, electronic, and infrared spectral studies.

  4. Spectroscopic evaluation of manganese(II) complexes derived from semicarbazones and thiosemicarbazones

    Science.gov (United States)

    Chandra, Sulekh; Gupta, Lokesh Kumar

    2005-09-01

    Manganese(II) complexes having the general composition Mn(L) 2X 2 [where L = isopropyl methyl ketone semicarbazone (LLA), isopropyl methyl ketone thiosemicarbazone (LLB), 4-aminoacetophenone semicarbazone (LLC) and 4-aminoacetophenone thiosemicarbazone (LLD) and X = Cl -, 1/2SO 42-] have been synthesized. All the complexes were characterized by elemental analyses, molar conductance, magnetic moment susceptibility, EI-mass, 1H NMR, IR, EPR and electronic spectral studies. All the complexes show magnetic moments corresponding to five unpaired electrons. The possible geometries of the complexes were assigned on the basis of EPR, electronic and infrared spectral studies.

  5. The antimicrobial activity of lapachol and its thiosemicarbazone and semicarbazone derivatives

    Science.gov (United States)

    Souza, Marina Azevêdo; Johann, Susana; Lima, Luciana Alves Rodrigues dos Santos; Campos, Fernanda Fraga; Mendes, Isolda Castro; Beraldo, Heloisa; de Souza-Fagundes, Elaine Maria; Cisalpino, Patrícia Silva; Rosa, Carlos Augusto; Alves, Tânia Maria de Almeida; de Sá, Nívea Pereira; Zani, Carlos Leomar

    2013-01-01

    Lapachol was chemically modified to obtain its thiosemicarbazone and semicarbazone derivatives. These compounds were tested for antimicrobial activity against several bacteria and fungi by the broth microdilution method. The thiosemicarbazone and semicarbazone derivatives of lapachol exhibited antimicrobial activity against the bacteria Enterococcus faecalis and Staphylococcus aureus with minimal inhibitory concentrations (MICs) of 0.05 and 0.10 µmol/mL, respectively. The thiosemicarbazone and semicarbazone derivatives were also active against the pathogenic yeast Cryptococcus gattii (MICs of 0.10 and 0.20 µmol/mL, respectively). In addition, the lapachol thiosemicarbazone derivative was active against 11 clinical isolates of Paracoccidioides brasiliensis, with MICs ranging from 0.01-0.10 µmol/mL. The lapachol-derived thiosemicarbazone was not cytotoxic to normal cells at the concentrations that were active against fungi and bacteria. We synthesised, for the first time, thiosemicarbazone and semicarbazone derivatives of lapachol. The MICs for the lapachol-derived thiosemicarbazone against S. aureus, E. faecalis, C. gattii and several isolates of P. brasiliensis indicated that this compound has the potential to be developed into novel drugs to treat infections caused these microbes. PMID:23778660

  6. The wide pharmacological versatility of semicarbazones, thiosemicarba-zones and their metal complexes.

    Science.gov (United States)

    Beraldo, Heloisa; Gambino, Dinorah

    2004-01-01

    The more significant bioactivities of a variety of semicarbazones (anti-protozoa, anticonvulsant) and thiosemicarbazones (antibacterial, antifungal, antitumoral, antiviral) and their metal complexes are reviewed together with proposed mechanisms of action and structure-activity relationships. Clinical or potential pharmacological applications of these versatile compounds are discussed. PMID:14754441

  7. The antimicrobial activity of lapachol and its thiosemicarbazone and semicarbazone derivatives

    Directory of Open Access Journals (Sweden)

    Marina Azevedo Souza

    2013-05-01

    Full Text Available Lapachol was chemically modified to obtain its thiosemicarbazone and semicarbazone derivatives. These compounds were tested for antimicrobial activity against several bacteria and fungi by the broth microdilution method. The thiosemicarbazone and semicarbazone derivatives of lapachol exhibited antimicrobial activity against the bacteria Enterococcus faecalis and Staphylococcus aureus with minimal inhibitory concentrations (MICs of 0.05 and 0.10 µmol/mL, respectively. The thiosemicarbazone and semicarbazone derivatives were also active against the pathogenic yeast Cryptococcus gattii (MICs of 0.10 and 0.20 µmol/mL, respectively. In addition, the lapachol thiosemicarbazone derivative was active against 11 clinical isolates of Paracoccidioides brasiliensis, with MICs ranging from 0.01-0.10 µmol/mL. The lapachol-derived thiosemicarbazone was not cytotoxic to normal cells at the concentrations that were active against fungi and bacteria. We synthesised, for the first time, thiosemicarbazone and semicarbazone derivatives of lapachol. The MICs for the lapachol-derived thiosemicarbazone against S. aureus, E. faecalis, C. gattii and several isolates of P. brasiliensis indicated that this compound has the potential to be developed into novel drugs to treat infections caused these microbes.

  8. Growth and characterization of organic NLO crystals of semicarbazone of acetophenone

    Science.gov (United States)

    Vijayan, N.; Ramesh Babu, R.; Gopalakrishnan, R.; Dhanuskodi, S.; Ramasamy, P.

    2001-12-01

    Semicarbazone of acetophenone is one of the potential organic NLO materials for photonic and optoelectronic applications. This crystal has been grown by slow evaporation technique. X-ray, FT-IR, melting point and UV-Visible methods are used to characterize the grown crystals.

  9. Magnetic properties of Fe, Co, Ni complexes of 3-semicarbazone isatine and 3-oxime isatine complexes

    Science.gov (United States)

    Zentkova, M.; Kovac, J.; Zentko, A.; Hudak, A.; Kosturiak, A.

    1994-03-01

    Magnetic measurements of the Fe, Co, Ni complexes of 3-semicarbazone isatine and 3-oxime isatine complexes have been made. All the compounds investigated were ferromagnetic with the T(sub c) in the region 11,1 - 62,9 K. The respective Curie temperatures were found to be determined by the type of transition metal and organic ligand.

  10. (E)-4-(Benz­yloxy)benzaldehyde thio­semicarbazone

    OpenAIRE

    Tarafder, M. T. H.; Islam, M. A. A. A. A.; Crouse, K. A.; Chantrapromma, Suchada; Fun, Hoong-Kun

    2008-01-01

    In the title compound, C15H15N3OS, the thio­semicarbazone group adopts an E configuration with respect to the C=N bond. The benzaldehyde thio­semicarbazone fragment is almost planar [maximum deviation = 0.012 (1) Å], while the dihedral angle between the benz­yloxy and phenyl rings is 72.48 (5)°. In the crystal structure, mol­ecules are inter­connected by N—H⋯N and N—H⋯S hydrogen bonds, forming a two-dimensional network parallel to the bc plane and are further stacked along the a axis by π–π i...

  11. 3-Hydr­oxy-4-methoxy­benzaldehyde thio­semicarbazone hemihydrate

    OpenAIRE

    Fun, Hoong-Kun; Kia, Reza; D’Silva, E. Deepak; Patil, P. S.; S. M. Dharmaprakash

    2008-01-01

    The asymmetric unit of the title compound, C9H11N3O2S·0.5H2O, comprises two crystallograpically independent thio­semicarbazone mol­ecules (A and B) and a water mol­ecule of crystallization. In each of the thio­semicarbazone mol­ecules, intra­molecular O—H⋯O and N—H⋯N hydrogen bonds form five-membered rings, producing S(5) ring motifs. Inter­molecular O—H⋯S and N—H⋯O inter­actions between mol­ecule B and the water mol­ecule form a six-membered ring, producing an R 2 2(6) ring motif. Inter­mole...

  12. Spectroscopic and biological studies on newly synthesized nickel(II) complexes of semicarbazones and thiosemicarbazones

    Science.gov (United States)

    Chandra, Sulekh; Gupta, Lokesh Kumar

    2005-12-01

    Nickel(II) complexes, having the general composition Ni(L) 2X 2, have been synthesized [where L: isopropyl methyl ketone semicarbazone (LLA), isopropyl methyl ketone thiosemicarbazone (LLB), 4-aminoacetophenone semicarbazone (LLC) and 4-aminoacetophenone thiosemicarbazone (LLD) and X = Cl -, 1/2SO 42-]. All the Ni(II) complexes reported here have been characterized by elemental analyses, magnetic moments, IR, electronic and mass spectral studies. All the complexes were found to have magnetic moments corresponding to two unpaired electrons. The possible geometries of the complexes were assigned on the basis of electronic and infrared spectral studies. Newly synthesized ligand and its nickel(II) complexes have been screened against different bacterial and fungal growth.

  13. Electrochemical and positron annihilation studies of semicarbazones and thiosemicarbazones derived from ferrocene

    International Nuclear Information System (INIS)

    A series of six ferrocene derivates containing a semicarbazone or thiosemicarbazone side chain was investigated by cyclic voltammetry and positron annihilation lifetime measurements. Both the redox and the electron capture processes took place on the Fe atom. Correlations between the two methods were proposed. taking into account the substituents on the side chain of the compounds, their redox potentials and the probabilities of o-positronium (o-Ps), formation. (author)

  14. Growth and characterization of a new organic nonlinear optical crystal: semicarbazone of p-dimethylamino benzaldehyde

    Science.gov (United States)

    Manivannan, S.; Dhanuskodi, S.

    2003-10-01

    Semicarbazone of p-dimethylamino benzaldehyde (SCPDB) is a new organic material with interesting quadratic nonlinear optical properties, in particular second harmonic generation (SHG). SCPDB was synthesized and single crystals were grown by low temperature solution method. Unit cell parameters were evaluated by single crystal X-ray diffraction technique. The formation of the material was confirmed qualitatively by FT-IR and FT-Raman spectral analyses and its optical transmittance studied. SHG efficiency is found to be comparable to urea.

  15. Electrochemical and positron annihilation studies of semicarbazones and thiosemicarbazones derived from ferrocene

    Energy Technology Data Exchange (ETDEWEB)

    Graudo, Jose Eugenio J.C. [Juiz de Fora Univ., MG (Brazil). Dept. de Quimica; Filgueiras, Carlos A.L. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Inst. de Quimica. Dept. de Quimica Inorganica; Marques-Netto, Antonio [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Dept. de Quimica; Batista, Alzir A. [Sao Carlos Univ., SP (Brazil). Dept. de Quimica

    2000-06-01

    A series of six ferrocene derivates containing a semicarbazone or thiosemicarbazone side chain was investigated by cyclic voltammetry and positron annihilation lifetime measurements. Both the redox and the electron capture processes took place on the Fe atom. Correlations between the two methods were proposed. taking into account the substituents on the side chain of the compounds, their redox potentials and the probabilities of o-positronium (o-Ps), formation. (author)

  16. Synthesis and Crystal Structure of a Cobalt(Ⅱ) Complex of Schiff Base from Pyridine-4-aldehyde and Semicarbazone%Schiff碱吡啶-4-甲醛缩氨基脲钴(Ⅱ)配合物的合成及其晶体结构

    Institute of Scientific and Technical Information of China (English)

    周健; 刘星; 陈振锋; 梁宏

    2006-01-01

    A novel cobalt(Ⅱ) complex, [Co(H4FoPyS)2(H2O)4](ClO4)2·2H2O(1, H4FoPyS=pyridine-4-carbaldehyde semicarbazone), was synthesized by the reaction of Co(ClO4)2·6H2O with the Schiff base derived from pyridine-4-aldehyde and semicarbazide. The structure of 1 was characterized by IR, single crystal X-ray diffraction and elemental analysis. The crystal of 1 belongs to triclinic system with space group Pī. The unit cell parameters are as follows: a=6.9015(13) (°A), b=10.2030(19) (°A), c=11.136(2)(°A), α=104.960(3)°, β=90.090(3)°, γ=108.177(4), V=716.9(2) (°A)3, Dc=1.613 mg·m-3, Z=1, Mr=696.29, μ=0.868 mm-1 and F(000)=359, R1=0.0857 and wR2=0.2361. The single crystal X-ray data of 1 reveal that the cobalt(Ⅱ) center adopts a trans-octahedral geometry comprised of two pyridine nitrogen atoms and two aqua oxygen atoms at the equatorial positions, and two aqua oxygen atoms at the axial positions. A three-dimensional framework of the molecule is formed by the combination of hydrogen bonds(N-H┈O and O-H┈O).%由Co(ClO4)2·6H2O和Schiff碱吡啶-4-甲醛缩氨基脲反应合成了标题化合物[Co(H4FoPyS)2(H2O)4](ClO4)2·2H2O(1, H4FoPyS为Schiff碱吡啶-4-甲醛缩氨基脲),其结构经IR,单晶X-射线衍射和元素分析表征.1属三斜晶系,空间群Pī, a=6.9015(13) (°A), b=10.2030(19) (°A), c=11.136(2) (°A), α=104.960(3)°, β=90.090(3)°, γ=108.177(4), V=716.9(2) (°A)3, Dc=1.613 mg·m-3, Z=1, Mr=696.29, μ=0.868 mm-1和F(000)=359,最终偏差因子分别为R1=0.0857和Wr2=0.2361.在1的晶体结构中,Co(Ⅱ)是六配位的稍变形八面体构型,其中2个吡啶氮原子和2个配位水分子占据赤道平面,另外2个配位水分子处于轴向位置.配合物分子通过氢键(N-H┈O和O-H┈O)相连,形成三维超分子网状结构.

  17. 吡啶-4-甲醛缩氨基脲锌(Ⅱ)配合物的合成及其晶体结构%Synthesis and Crystal Structure of Zinc(Ⅱ) Complex with Schiff Base from Pyridine-4-aldehyde and Semicarbazone

    Institute of Scientific and Technical Information of China (English)

    周健; 刘星; 李冬青; 袁余洲; 陈振锋; 张勇

    2006-01-01

    利用水热法合成了标题化合物[Zn(H4FoPyS)2(H2O)4](NO3)2·3(H2O)(1, H4FoPyS为希夫碱吡啶-4-甲醛缩氨基脲),其结构经IR, 元素分析, 单晶X-射线衍射和热重分析表征.1的晶体结构属三斜晶系, 空间群Pī, a=9.6505(16) (°A), b=12.644(2) (°A), c=13.156(2) (°A), α=115.459(3)°, β=90.0290(10)°, γ=111.792(3), V=1321.1(4) (°A)3, Dc=1.609 g·cm-3, Z=2, Mr=647.84, μ=1.905 mm-1和F(000)=728,最终偏差因子分别为R1=0.0365和wR2=0.0878.1中Zn(Ⅱ)是六配位的稍变形八面体构型,其中2个吡啶氮原子和2个配位水分子占据赤道平面,另外2个配位水分子处于轴向位置.%A novel zinc(Ⅱ) complex, [Zn(H4FoPyS)2(H2O)4](NO3)2·3(H2O)(1)(H4FoPyS=pyridine-4-aldehyde semicarbazone), was synthesized by hydrothermal method. The structure of 1 was characterized by IR, elemental analysis, single crystal X-ray diffraction and thermal analysis. The crystal of 1 belongs to triclinic with space group Pī. The unit cell parameters are as follows: a=9.6505(16) (°A), b=12.644(2)(°A), c=13.156(2) (°A), α=115.459(3)°, β=90.0290(10)°, γ=111.792(3), V=1321.1(4) (°A)3, Dc=1.609 g·cm-3, Z=2, Mr=647.84, μ=1.905 mm-1 and F(000)=728, R1=0.0365 and wR2=0.0878. The zinc(Ⅱ) center adopts a slightly distorted octahedral geometry comprised of two pyridine nitrogen atoms and two aqua oxygen atoms at the equatorial positions, and two aqua oxygen atoms at the axial positions.

  18. Crystal structures of crotonaldehyde semicarbazone and crotonaldehyde thiosemicarbazone from X-ray powder diffraction data

    OpenAIRE

    Atef Arfan; Mwaffak Rukiah

    2015-01-01

    Crotonaldehyde semicarbazone {systematic name: (E)-2-[(E)-but-2-en-1-ylidene]hydrazinecarboxamide}, C5H9N3O, (I), and crotonaldehyde thiosemicarbazone {systematic name: (E)-2-[(E)-but-2-en-1-yldene]hydrazinecarbothioamide}, C5H9N3S, (II), show the same E conformation around the imine C=N bond. Compounds (I) and (II) were obtained by the condensation of crotonaldehyde with semicarbazide hydrochloride and thiosemicarbazide, respectively. Each molecule has an intramolecular N—H...N hydrogen bond...

  19. Four transition metal complexes with a semicarbazone ligand bearing pyrazine unit

    Science.gov (United States)

    Chen, Hong; Ma, Xiu-qin; Lv, Yan-yun; Jia, Lei; Xu, Jun; Wang, Yuan; Ge, Zhi-jun

    2016-04-01

    Four new complexes based on L (where L = 3-ethyl-2-acetylpyrazine semicarbazone), namely [CoL2]Cl2·0.5H2O (1), [CoL2](NO3)2 (2), [CdL(H2O)2(NO3)](NO3)·H2O (3) and [CuL(CH3OH)Cl2]·[CuLCl2] (4) have been synthesized and characterized by X-ray diffraction analyses. The results show that the semicarbazone acts as a tridentate neutral ligand in all complexes. Each of complex 1 and 2 reveals a distorted octahedral geometry around the metal ion provided by two units of the ligand, while the ratio of the ligand and metal is 1:1 in complexes 3 and 4. The effect of complexes 1-4 on cell proliferation, apoptosis of human pancreatic cancer (Patu8988), human gastric cancer (SGC7901) and human hepatic cancer (SMMC7721) cell lines have been detected by MTT assay, Annexin V/PI double staining flow cytometry and TUNEL assay. The results show that complexes 1-4 can inhibit cell proliferation of Patu8988, SGC7901 and SMMC7721 cells, significantly higher than the effect of the ligand. However, the complex 4 reveals higher apoptosis rate, and displays up-regulated expression level of caspase 3, detected by western blotting, which also indicates the complex 4 can induce caspase-dependent cell apoptosis in SMMC7721.

  20. Metal complexes of 2-benzoylpyridine semicarbazone: Spectral, electrochemical and structural studies

    Science.gov (United States)

    Pérez-Rebolledo, Anayive; Piro, Oscar E.; Castellano, Eduardo E.; Teixeira, Letícia R.; Batista, Alzir A.; Beraldo, Heloisa

    2006-08-01

    2-Benzoylpyridine semicarbazone (H2BzPS) and its complexes [Cu(H2BzPS)Cl 2] ( 1) and [Zn(H2BzPS)Cl 2] ( 2) have been synthesized and their spectral properties have been studied. The electrochemical behaviour of [Cu(H2BzPS)Cl 2] ( 1) has been investigated. [Cu(H2BzPS)Cl 2] ( 1) crystallizes in the triclinic P-1 space group, a=9.278(1), b=12.848(1), c=13.923(1) Å, α=84.54(1), β=71.91(1), γ=85.14(1)°, with two complexes per asymmetric unit ( Z=4) and a disordered methanol solvent molecule (occupancy=1/4). [Zn(H2BzPS)Cl 2] ( 2) crystallizes in the orthorhombic P2 12 12 1 space group with a=11.983(1), b=14.067(1), c=18.706(1) Å, and two independent molecules per asymmetric unit ( Z=8). In both cases, the neutral semicarbazone acts as a tridentate ligand which coordinates the metal through the pyridine and imine nitrogen atoms and the carbonyl oxygen. Two chloride ions occupy the fourth and fifth coordination positions.

  1. Structure and spectral properties of dinuclear zinc complex containing semicarbazonate ligands

    Science.gov (United States)

    Jing-Lin, Wang; Jiao, Feng; Mei-Ping, Xu; Bin-Sheng, Yang

    2011-04-01

    The dinuclear Zn 2+ complex [Zn(HSSC)OAc] 2·2DMF (H 2SSC = salicylaldehyde semicarbazone; HOAc = acetic acid; DMF = N,N-dimethylfomamide) was prepared and structurally characterized by single crystal X-ray. The basic structural unit of the complex is a dinuclear complex [Zn(HSSC)OAc] 2 in which the semicarbazone ligand adopts the phenol-imine form. The deprotonated phenol group forms a one-atom bridge between the two zinc centers, and both of the zinc centers are five-coordinated. The local coordination environment of Zn 2+ can be approximately considered as square pyramidal. UV spectral studies show that the H 2SSC provides strong binding of Zn 2+ in a 1:1 ratio in solution. The conditional binding constant of the complex is lg KZn-L = 12.89 ± 0.76 in 0.05 M Tris-HCl buffer at pH 7.4. The H 2SSC exhibits an enhanced fluorescence effect by the addition of Zn 2+, and affords an excellent selectivity for Zn 2+ under physiological conditions.

  2. Crystal structures of crotonaldehyde semicarbazone and crotonaldehyde thiosemicarbazone from X-ray powder diffraction data

    OpenAIRE

    Arfan, Atef; Rukiah, Mwaffak

    2015-01-01

    Crotonaldehyde semicarbazone {systematic name: (E)-2-[(E)-but-2-en-1-yl­idene]hydrazinecarboxamide}, C5H9N3O, (I), and crotonaldehyde thio­semi­carba­zone {systematic name: (E)-2-[(E)-but-2-en-1-yldene]hydra­zinecarbo­­thio­amide}, C5H9N3S, (II), show the same E conformation around the imine C=N bond. Compounds (I) and (II) were obtained by the condensation of crotonaldehyde with semicarbazide hydro­chloride and thio­semicarbazide, respectively. Each mol­ecule has an intra­molecular N—H⋯N hyd...

  3. 2-Hydroxy­imino-1-phenyl­ethanone thio­semicarbazone monohydrate

    OpenAIRE

    Sarıkavaklı, Nursabah; Babahan, İknur; Şahin, Ertan; Hökelek, Tuncer

    2008-01-01

    In the title thio­semicarbazone derivative, C9H10N4OS·H2O, intra­molecular N—H⋯N hydrogen bonds result in the formation of two nearly coplanar five- and six-membered rings, which are also almost coplanar with the adjacent phenyl ring. The oxime group has an E configuration and is involved in inter­molecular O—H⋯O hydrogen bonding as a donor. In the crystal structure, intra­molecular O—H⋯S and N—H⋯N and inter­molecular O—H⋯O and N—H⋯S hydrogen bonds generate edge-fused R 2 2(8) and R 4 1(11) r...

  4. Syntheses of Nickel (II Complexes from Novel Semicarbazone Ligands with Chloroformylarylhydrazine, Benzimidazole and Salicylaldehyde Moieties

    Directory of Open Access Journals (Sweden)

    Mei-Hsiu Shih

    2015-03-01

    Full Text Available This study addressed the design and syntheses of diverse ligands, which were then successfully treated with Ni (II ion to afford a series of nickel complexes. α-Chloroformylarylhydrazine hydrochlorides 6 contain two different functional groups. One is a strong nucleophile, and the other is a good electrophile. Therefore, it can be designed to react with several reagents to obtain diverse derivatives which can be used as ligands for metal complexes. Furthermore, benzimidazole and salicylaldehyde can provide electron donor sites, N and O electron donors, separately. Hence, the starting materials α-chloroformylarylhydrazine hydrochlorides 6 were first treated with 2-(aminomethyl-benzimidazole (7 to give the corresponding semicarbazides 8. Then, the semicarbazides 8 reacted with various substituted salicylaldehydes 9–11 to afford the desired substituted-salicylaldehyde 2-aryl-4-substituted semicarbazones 12–14, which could coordinate with nickel (II ion to give the corresponding nickel complexes 15–17.

  5. FT-IR, FT-Raman and Computational Study of Ethyl Methyl Ketone Semicarbazone

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    P. S. Binil

    2011-01-01

    Full Text Available FT-IR and FT-Raman spectra of ethyl methyl ketone semicarbazone were recorded and analyzed. The vibrational wavenumbers were computed using HF/6-31G*, B3PW91/6-31G* and B3LYP/6-31G* basis and compared with experimental data. The first hyperpolarizability, infrared intensities and Raman activities are reported. The calculated first hyperpolarizability is comparable with the reported values of similar derivatives and is an attractive object for future studies of non-linear optics. The extended π-electron delocalization over the carbazone moiety is responsible for the nonlinearity of the molecule. The geometrical parameters of the title compound are in agreement with that of similar derivatives. The red shift of the NH stretching wavenumber in the infrared spectrum from the computed wavenumber indicates the weakening of the NH bond resulting in proton transfer to the neighboring oxygen atom.

  6. Synthesis molecular modeling and anticonvulsant activity of some hydrazone, semicarbazone, and thiosemicarbazone derivatives of benzylidene camphor

    OpenAIRE

    Agrawal, Saurabh

    2014-01-01

    Saurabh Agrawal,1 Jainendra Jain,2 Ankit Kumar,3 Pratibha Gupta,4 Vikas Garg5 1Meerut Institute of Engineering and Technology, Meerut, Uttar Pradesh, India; 2Ram–Eesh Institute of Vocational and Technical Education, Greater Noida, Uttar Pradesh, India; 3Kharvel Subharti College of Pharmacy, Swami Vivekanand Subharti University, Meerut, Uttar Pradesh, India; 4Atarra Degree College, Atarra, Banda, India; 5Manipal College of Pharmaceutical Sciences, Manipal University, Manipal, Karnata...

  7. SYNTHESIS AND ANTICONVULSANT ACTIVITY OF SOME NOVEL SEMICARBAZONE DERIVATIVES CONTAINING QUINOXALINE MOIETY

    Directory of Open Access Journals (Sweden)

    Rakesh Sahu*, Sonal Tiwari, Jay Kumar Chandra and Prabhat Kumar Patel

    2012-11-01

    Full Text Available Various 1-(substituted benzylidene-5-(3-hydroxyquinoxaline-2-yl carbonohydrazide were synthesized starting from orthophenylenediamine. Structures of all the compounds were confirmed on the basis of spectral analyses. All the newly synthesized compounds were screened for anticonvulsant activity. Some of the compounds showed significant anticonvulsant activity with no neurotoxicity

  8. Synthesis and characterization of semicarbazone metal complexes of Sn (Ⅳ) and Zr (Ⅳ)

    Institute of Scientific and Technical Information of China (English)

    YIN Dong-Dong (尹冬冬); SHAN, Lu(单璐); WANG, Zhi-Wen(王志文)

    2000-01-01

    Three semicarbazonyl ligands were synthesized and used to form six novel organometallic complexes with Ph2SnCl2 and Cp2ZrC2. All these complexes were characterized by IR、1H NMR、MS and elemental analysis.

  9. Stability of pyridoxal-5-phosphate semicarbazone: applications in plasma vitamin B6 analysis and population surveys of vitamin B6 nutritional status.

    Science.gov (United States)

    Ubbink, J B; Serfontein, W J; de Villiers, L S

    1985-08-01

    The determination of pyridoxal-5-phosphate (PLP) and pyridoxal (PL) in plasma requires the availability of dark room facilities, due to the photosensitivity of these vitamin B6 vitamers. The fact that the semicarbazone forms of PL and PLP are more strongly fluorescent than the underivatized B6 vitamers has been exploited in plasma analyses, but it was not previously realised that these semicarbazone forms are also very stable even under conditions that lead to rapid decomposition of free PL and PLP. The stabilisation of PLP and PL obtained in this manner is sufficient and fully adequate to meet the practical requirements of clinical field studies. We report a high-performance liquid chromatographic method for plasma PLP and PL determinations based on precolumn semicarbazone formation and fluorescence detection. The method is sensitive enough for quantitative plasma PLP determinations even in B6-deficient patients. PMID:4055950

  10. Crystal structures of crotonaldehyde semicarbazone and crotonaldehyde thiosemicarbazone from X-ray powder diffraction data.

    Science.gov (United States)

    Arfan, Atef; Rukiah, Mwaffak

    2015-02-01

    Crotonaldehyde semicarbazone {systematic name: (E)-2-[(E)-but-2-en-1-yl-idene]hydrazinecarboxamide}, C5H9N3O, (I), and crotonaldehyde thio-semi-carba-zone {systematic name: (E)-2-[(E)-but-2-en-1-yldene]hydra-zinecarbo--thio-amide}, C5H9N3S, (II), show the same E conformation around the imine C=N bond. Compounds (I) and (II) were obtained by the condensation of crotonaldehyde with semicarbazide hydro-chloride and thio-semicarbazide, respectively. Each mol-ecule has an intra-molecular N-H⋯N hydrogen bond, which generates an S(5) ring. In (I), the crotonaldehyde fragment is twisted by 2.59 (5)° from the semicarbazide mean plane, while in (II) the corresponding angle (with the thio-semicarbazide mean plane) is 9.12 (5)°. The crystal packing is different in the two compounds: in (I) inter-molecular N-H⋯O hydrogen bonds link the mol-ecules into layers parallel to the bc plane, while weak inter-molecular N-H⋯S hydrogen bonds in (II) link the mol-ecules into chains propagating in [110]. PMID:25878810

  11. Identification of semicarbazones, thiosemicarbazones and triazine nitriles as inhibitors of Leishmania mexicana cysteine protease CPB.

    Directory of Open Access Journals (Sweden)

    Jörg Schröder

    Full Text Available Cysteine proteases of the papain superfamily are present in nearly all eukaryotes. They play pivotal roles in the biology of parasites and inhibition of cysteine proteases is emerging as an important strategy to combat parasitic diseases such as sleeping sickness, Chagas' disease and leishmaniasis. Homology modeling of the mature Leishmania mexicana cysteine protease CPB2.8 suggested that it differs significantly from bovine cathepsin B and thus could be a good drug target. High throughput screening of a compound library against this enzyme and bovine cathepsin B in a counter assay identified four novel inhibitors, containing the warhead-types semicarbazone, thiosemicarbazone and triazine nitrile, that can be used as leads for antiparasite drug design. Covalent docking experiments confirmed the SARs of these lead compounds in an effort to understand the structural elements required for specific inhibition of CPB2.8. This study has provided starting points for the design of selective and highly potent inhibitors of L. mexicana cysteine protease CPB that may also have useful efficacy against other important cysteine proteases.

  12. Crystal structures of crotonaldehyde semicarbazone and crotonaldehyde thiosemicarbazone from X-ray powder diffraction data

    Directory of Open Access Journals (Sweden)

    Atef Arfan

    2015-02-01

    Full Text Available Crotonaldehyde semicarbazone {systematic name: (E-2-[(E-but-2-en-1-ylidene]hydrazinecarboxamide}, C5H9N3O, (I, and crotonaldehyde thiosemicarbazone {systematic name: (E-2-[(E-but-2-en-1-yldene]hydrazinecarbothioamide}, C5H9N3S, (II, show the same E conformation around the imine C=N bond. Compounds (I and (II were obtained by the condensation of crotonaldehyde with semicarbazide hydrochloride and thiosemicarbazide, respectively. Each molecule has an intramolecular N—H...N hydrogen bond, which generates an S(5 ring. In (I, the crotonaldehyde fragment is twisted by 2.59 (5° from the semicarbazide mean plane, while in (II the corresponding angle (with the thiosemicarbazide mean plane is 9.12 (5°. The crystal packing is different in the two compounds: in (I intermolecular N—H...O hydrogen bonds link the molecules into layers parallel to the bc plane, while weak intermolecular N—H...S hydrogen bonds in (II link the molecules into chains propagating in [110].

  13. Crystal structures of crotonaldehyde semicarbazone and crotonaldehyde thiosemicarbazone from X-ray powder diffraction data

    Science.gov (United States)

    Arfan, Atef; Rukiah, Mwaffak

    2015-01-01

    Crotonaldehyde semicarbazone {systematic name: (E)-2-[(E)-but-2-en-1-yl­idene]hydrazinecarboxamide}, C5H9N3O, (I), and crotonaldehyde thio­semi­carba­zone {systematic name: (E)-2-[(E)-but-2-en-1-yldene]hydra­zinecarbo­­thio­amide}, C5H9N3S, (II), show the same E conformation around the imine C=N bond. Compounds (I) and (II) were obtained by the condensation of crotonaldehyde with semicarbazide hydro­chloride and thio­semicarbazide, respectively. Each mol­ecule has an intra­molecular N—H⋯N hydrogen bond, which generates an S(5) ring. In (I), the crotonaldehyde fragment is twisted by 2.59 (5)° from the semicarbazide mean plane, while in (II) the corresponding angle (with the thio­semicarbazide mean plane) is 9.12 (5)°. The crystal packing is different in the two compounds: in (I) inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into layers parallel to the bc plane, while weak inter­molecular N—H⋯S hydrogen bonds in (II) link the mol­ecules into chains propagating in [110]. PMID:25878810

  14. Mg(II Selective PVC Membrane Electrode Based on Methyl Phenyl Semicarbazone as an Ionophore

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    Sulekh Chandra

    2013-01-01

    Full Text Available A PVC-membrane-based Mg(II selective electrode was constructed using methyl phenyl semicarbazone (MPS as a neutral carrier. The sensor exhibits a Nernstian response for Mg(II ion over a wide concentration range 1.0×10-8  to  1.0×10-1 M with the slope of 28.4 mV/per decade having detection limit 1.7×10-9 M. It was relatively a fast response time (<10 s for concentration ≥1.0×10-3 and <15 s for concentration of ≥1.0×10-6 M and can be used for 8 months without any considerable divergence in potentials. The proposed sensor revealed relatively good selectivity and high sensitivity for Mg(II over a mono-, di-, and trivalent cation and can be used in a pH range of 1.0–9.5. It was also successfully used as an indicator electrode in potentiometer titration and in the analysis of concentration of magnesium in various real samples.

  15. Hepatoprotective effect of acetone semicarbazone on Ehrlich ascites carcinoma induced carcinogenesis in experimental mice

    Institute of Scientific and Technical Information of China (English)

    Farhadul Islam; Shaikh Mohummad Mohsin Ali; Jahan Ara Khanam

    2013-01-01

    Objective:To determine the hepatoprotective effect of acetone semicarbazone (ASC) in vivo in normal and Ehrlich ascites carcinoma (EAC) bearing male Swiss albino mice. Methods:Drug-induced changes in biochemical and behavioral parameters at dose of 2.0 mg/kg body weight for 14 d and nullifying the toxicity induced by EAC cells were studied. The histopathology studies of the protective effects of ASC on vital organs were also assessed. Results:The administration of ASC made insignificant changes in body weight and behavioral (salivation, diarrhea, muscular numbness) changes during treatment period due to minor toxicity were minimized after the treatment in normal mice. The biochemical parameters, including serum glutamate pyruvate transaminase, glutamate oxaloactate transaminase, alkaline phosphatase, serum glucose, cholesterol, urea, triglyceride and billirubin changed modestly in normal mice receiving ASC. Though the treatment continued, these values gradually decreased to normal level after the treatment. In EAC bearing mice, the toxic effects due to EAC cells in all cases were nullified by treatment with the ASC. Significant abnormalities were not detected in histology of the various organs of the normal mice treated with ASC. Conclusions: ASC can, therefore, be considered safe in formulating novel anticancer drug, as it exhibits strong protective effect against EAC cell bearing mice.

  16. KBrO3/MoO3: An efficient reagent system for the oxidative deprotection of semicarbazones,1,1-diacetates and acetals

    Institute of Scientific and Technical Information of China (English)

    Farhad Shirini; Zahra Neyestani; Masoumeh Abedini

    2009-01-01

    Semicarbazones,1,1-diacetates and acetals are efficiently converted to their corresponding carbonyl compounds using synergistic effect between KBrO3 and MoO3 in refluxing CH3CN-H20 in good to high yields.

  17. Spectroscopic evaluation of Co(II), Ni(II) and Cu(II) complexes derived from thiosemicarbazone and semicarbazone

    Science.gov (United States)

    Chandra, Sulekh; Kumar, Anil

    2007-12-01

    Co(II), Ni(II) and Cu(II) complexes were synthesized with thiosemicarbazone (L 1) and semicarbazone (L 2) derived from 2-acetyl furan. These complexes were characterized by elemental analysis, molar conductance, magnetic moment, mass, IR, electronic and EPR spectral studies. The molar conductance measurement of the complexes in DMSO corresponds to non-electrolytic nature. All the complexes are of high-spin type. On the basis of different spectral studies six coordinated geometry may be assigned for all the complexes except Co(L) 2(SO 4) and Cu(L) 2(SO 4) [where L = L 1 and L 2] which are of five coordinated square pyramidal geometry.

  18. The Investigation of Electronic Properties and Microscopic Second-Order Nonlinear Optical Behavior of 1-SALICYLIDENE-3-THIO-SEMICARBAZONE

    Science.gov (United States)

    Karakas, Asli; Unver, Huseyin; Elmali, Ayhan

    To investigate the microscopic second-order nonlinear optical (NLO) behavior of the 1-salicylidene-3-thio-semicarbazone Schiff base compound, the electric dipole moments (μ), linear static polarizabilities (α) and first static hyperpolarizabilites (β) have been calculated using finite field second-order Møller-Plesset perturbation (FF MP2) theory. The ab-initio results on (hyper)polarizabilities show that the investigated molecule might have microscopic NLO properties with non-zero values. To understand the NLO behavior in the context of molecular orbital structure, we have also examined the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and the HOMO-LUMO gap in the same theoretical framework as the (hyper)polarizability calculations. In addition to the NLO properties, the electronic transition spectra have been computed using a semi-empirical method (ZINDO). ZINDO calculation results show that the electronic transition wavelengths have been estimated to be shorter than 400 nm.

  19. Experimental and theoretical assessment of the mechanism involved in the reaction of steroidal ketone semicarbazone with hydrogen peroxide

    Science.gov (United States)

    Sharma, Kamlesh; Mishra, Shivani B.; Mishra, Ajay K.

    2011-09-01

    3β-Acetoxy-5α-cholestan-6-one semicarbazone 1 on reaction with hydrogen peroxide affords selectively 3β-acetoxy-5α-cholestan-6-spiro-1',2',4'-triazolidine-3'-one 2. The structural assignment of the product was confirmed by spectral data and elemental analysis. A free radical mechanism of the present reaction was described successfully by calculating theoretical models of 1, A, B and 2, using DFT with B3LYP/6-31G* basis set. It was found that the reaction undergoes through the formation of two radical intermediates and the only one isomer of the product in which -NH-CO- group is cis with respect C5α-H, was selectively obtained. Frontier molecular orbital, spin electronic density, electrostatic potential and atomic charges were discussed.

  20. Crystal growth and characterization of a novel organic nonlinear optical material: semicarbazone of p-dimethylamino benzaldehyde

    Science.gov (United States)

    Dhanuskodi, Sivasubramanian; Manivannan, Sellaperumal

    2003-06-01

    The semicarbazone of p-dimethylamino benzaldehyde (SCPDB) is a potential organic nonlinear optical material. SCPDB has been synthesized and the solubility studies were carried out in the temperature range 30-60°C. Following the slow evaporation technique, single crystals of SCPDB have been grown and the unit cell parameters have been evaluated by single crystal x-ray diffraction technique. The UV-Vis-NIR transmittance spectrum was recorded in the range 200-1100nm. Fourier transform IR and Fourier transform Raman spectra were recorded in the range 400-4000 cm-1 and the characteristic vibrational frequencies of the functional groups present in the system have been assigned. Second Harmonic Generation efficiency measurements were carried out using Nd:YAG laser.

  1. Synthesis and Structural Characterization of Schiff Base Ligand and their Metal Complexes

    Directory of Open Access Journals (Sweden)

    Amit Kumar Gautam

    2016-05-01

    Full Text Available In the present work, the synthesis and structural characterization of a 2-phenyl- 3(benzamido propyl quinazoline (3H -4- one semicarbazone/ thiosemicarbazone hydrochloride and its metal complexes have been reported. All the synthesized compounds were characterized by using various physico-chemical techniques such as Infrared spectra, electronic spectra, molar conductivity and magnetic susceptibility measurements. The ligand and metal ions reacted to form in the 2:1 ratio as found from the elemental analyses and general stiochiometry was determined, [M(PBPQS2X2] and [M(PBPQT2X2]; where M = Co(II, Ni(II and Cu(II; PBPQS = 2-phenyl- 3 (benzamido propyl quinazoline (3H -4- one semicarbazone and PBPQT = 2- phenyl- 3 (benzamido propyl quinazoline (3H -4- one thiosemicarbazone. On the basis of analytical data, a proposed structure for the Cu(II complexes are distorted octahedral and those for Co(II and Ni(II complexes are octahedral. Ligands PBPQS/ PBPQT have been proposed to act in a bidentate manner co-ordinating to the metal ions though azomethine nitrogen and oxygen/ sulphur atom of either semicarbazone/ thiosemicarbazone moiety. The remaining co-ordination sites are occupied by negative ions such as Cl-, Br-, I- or NO3-. The ligands and its metal complexes were tested for their possible antimicrobial potentials.

  2. Preparation, crystallography and spectroscopic properties of the polymeric {(1-( E)-2-pyridinylmethylidene)semicarbazone)(aqua)copper(II)} sulphate dihydrate complex: Evidence of dynamic Jahn-Teller effect

    Science.gov (United States)

    Garbelini, Ellery R.; Ribeiro, Ronny Rocha; Hörner, Manfredo; Locatelli, Aline; Nunes, Fábio S.

    2011-05-01

    Pyridine-2-carbaldehyde semicarbazone ligand (HL) reacts with copper(II) sulphate in water solution to yield the coordination polymer [{Cu II(HL)(H 2O)(SO 4)} n] (1). The crystals are triclinic with space group P(-1) and the metal ion is occupying a distorted octahedral geometry. EPR results show that a dynamic Jahn-Teller (J-T) effect is operative in water solutions and also support the stability of the polymeric chains as they continue to show a characteristic half-field Δ mS = ±2 transitions. UV-visible spectrum analysis allowed access to the J-T stabilization energy of 5995 cm -1 in water. Thermogravimetric/differential thermal analysis curves showed a step-by-step decomposition of complex 1 with loss of water, release of SO 3 and oxidation of the semicarbazone ligand in the 30-422 °C range.

  3. Semicarbazonas e tiossemicarbazonas: o amplo perfil farmacológico e usos clínicos Semicarbazones and thiosemicarbazones: their wide pharmacological profile and clinical applications

    OpenAIRE

    Heloisa Beraldo

    2004-01-01

    This article shows that thiosemicarbazones, semicarbazones and their metal complexes can exhibit target selectivity along with a wide pharmacological profile. Complexes of thiosemicarbazones with cytotoxic or antitumoral activity are presented, some of which show activity against cisplatinum-resistant cells. The inhibition mechanism of the enzyme ribonucleoside diphosphate reductase (RDR), involved in DNA syntheses, by alpha(N)-heterocyclic thiosemicarbazones is discussed. The encouraging res...

  4. Crystal structure and spectroscopic study on photochromism of 1,3-diphenyl-4-(4‧-fluoro)benzal-5-pyrazolone N(4)-phenyl semicarba-zone

    Science.gov (United States)

    Chai, Hui; Liu, Guangfei; Liu, Lang; Jia, Dianzeng; Guo, Zaiping; Lang, Jianping

    2005-10-01

    A novel compound 1,3-diphenyl-4-(4'-fluoro)benzal-5-pyrazolone N(4)-phenyl semicarbazone (DP4FBP-PSC) has been synthesized. X-ray single crystal structure analysis shows that the compound has interlaced structure linked by intermolecular hydrogen bonds. The results of fluorescence emission spectroscopy, UV-Vis reflection spectroscopy and the reaction rate constant indicate that DP4FBP-PSC is photochromic material. Its photochromic mechanism was investigated by structure analysis.

  5. {sup 64} Cu-pyruvaldehide-bis-(N{sup 4} methyl-thio semi-carbazone) - Cu-PTSM as brain tracer for positron emission tomography; Cu-piruvaldehido-bis-(N{sup 4} metiltiosemicarbazona) o Cu-PSTM como trazador cerebral para tomografia por emision de positrones

    Energy Technology Data Exchange (ETDEWEB)

    Arguelles, M.G.; Lago Fernandez, J.L.; Casale, G.A.; Torres, E.A. [Comision Nacional de Energia Atomica, Buenos Aires (Argentina)

    1995-12-31

    Synthesis of Pyruvaldehide-bis-(N{sup 4}-methyl-thio semicarbazone) PTSM used for medical investigation and diagnosis has been carried out in our Radiopharmaceutical Division in Centro Atomico Ezeiza. PTSM has been obtained introducing modifications to a previous synthesis published by H.G. Petering TLC, HPLC and IR, UV spectrum controls have been performed. Cu-64 can be obtained by the Cu-63 (n, {gamma}) and Zn-64 (n,p) reactions. This last reaction has been chosen for the production in the RA-3 reactor since it leads to Cu-64 of high specific activity. Two different assays have been performed to obtain the chelate PTSM-Cu-64. The first one has beer carried out by buffering the Cu-64 solution to pH 3-4; adding the PTSM solution in ethanol. The second assay has been carried out by buffering the Cu-64 solution with sodium acetate 3 M and adding 100 {mu}l of PTSM solution in ethanol. The chelate thus obtained is purified in Sepak C-18. Radiochemical purity has been tested by thin layer chromatography. Biodistribution studies have been carried on NIH mice and Wistar rats showing a brain uptake of 4%, 30 minutes after injection. Thus, FTMS-Cu-64 proves to be a good brain diagnosis agent. (author). 7 refs., 3 figs.

  6. Synthesis and Biological Activity Evaluation of Schiff Bases of 5-Acyl-1,2,4-Triazine

    International Nuclear Information System (INIS)

    A simple and general method has been developed for the synthesis of various Schiff bases (oximes, hydrazones, semicarbazones and thiosemicarbazones) derived from 5-acyl-1,2,4-triazines. Some of the new synthesized Schiff bases were tested for biological activity but only oximes 2a-c shown poor antiviral activity. The oxime derivatives of 5-acyl-3-methylsulfanyl-1,2,4-triazine were tested with pea-seedling diamine oxidase as the enzyme is known to be inhibited by oxime compounds. However, only weak non-competitive inhibitory effects were observed (Ki of 10 /sup -2/ M). (author)

  7. SYNTHESIS, SPECTRAL CHARACTERIZATION OF Cu (II AND Ni (II COMPLEXES WITH THIOSEMICARBAZONES AND SEMICARBAZONES DERIVED FROM PYRIDINE-2- CARBOXALDEHYDE

    Directory of Open Access Journals (Sweden)

    Sulekh Chandra

    2013-08-01

    Full Text Available Ni (II and Cu (II complexes were synthesized with L1(Pyridine-2-carboxaldehydethiosemicarbazones and L2 (Pyridine-2-carboxaldehydesemicarbazones. These complexes were characterized by elemental analysis, molar conductance measurements, magnetic susceptibility measurements, mass, IR, electronic and EPR spectral studies. The molar conductance measurements on the complexes in DMSO correspond to non electrolytes nature with L1. The molar conductance measurements with L2 lie in the range 210-226 Ω-1cm2mol-1 indicating the complexes were 1:2 electrolyte thus the complexes may be formulated as [M(L2]X2 where M= Ni (II and Cu (II complexes. On the basis of spectral studies an octahedral geometry has been assigned for Ni (II complexes. A tetragonal geometry suggested for Cu (II complexes.

  8. SYNTHESIS, SPECTRAL CHARACTERIZATION OF Cu (II) AND Ni (II) COMPLEXES WITH THIOSEMICARBAZONES AND SEMICARBAZONES DERIVED FROM PYRIDINE-2- CARBOXALDEHYDE

    OpenAIRE

    Sulekh Chandra; Prem Ballabh; S.K Choudhary

    2013-01-01

    Ni (II) and Cu (II) complexes were synthesized with L1(Pyridine-2-carboxaldehydethiosemicarbazones) and L2 (Pyridine-2-carboxaldehydesemicarbazones). These complexes were characterized by elemental analysis, molar conductance measurements, magnetic susceptibility measurements, mass, IR, electronic and EPR spectral studies. The molar conductance measurements on the complexes in DMSO correspond to non electrolytes nature with L1. The molar conductance measurements with L2 lie in the range 210-2...

  9. 微波辐射合成丙酮缩氨基脲%SYNTHESIS OF ACETONE SEMICARBAZONE UNDER MICROWAVE RADIATION

    Institute of Scientific and Technical Information of China (English)

    李丕高; 王玫; 李延; 张茸

    2008-01-01

    在微波辐射下,以水合肼、尿素、丙酮为原料,采用一釜两步法合成了丙酮缩氨基脲.用单因素实验法考察了原料配比、微波辐射功率、辐射反应时间等条件对收率的影响.通过测定熔点和IR分析对产物进行了表征.结果表明:当n(水合胼):n(尿素):n(丙酮)=1:2.5:1.1,第一步反应的微波辐射功率为600 W,反应温度100℃,辐射反应时间20 min时,制得反应中间体氨基脲;第二步氨基脲不经分离,在微波辐射功率500 W,反应温度60℃,辐射反应时间15 min条件下,丙酮缩氨基脲的收率可达90.08%.

  10. One-pot Synthesis of Benzaldehyde Semicarbazone%一锅法合成苯甲醛缩氨基脲

    Institute of Scientific and Technical Information of China (English)

    孔祥文; 张静

    2002-01-01

    以水合肼、尿素和苯甲醛为原料,一锅法合成苯甲醛缩氨基脲,该工艺中间产物氨基脲不以氨基脲盐酸盐形式分离,直接与苯甲醛进行缩合反应,且不产生含肼废水.适宜的反应条件为:n(H2NNH2@H2O):n(H2NCONH2):n(C6H5CHO)=1.0:2.0:0.8,氨基脲合成反应温度98~101℃,反应时间3~4 h;缩合反应pH=3~4,滴加时间1.5 h,室温搅拌2 h,回流1 h,产物收率为98.0%.

  11. Spectroscopic and Biological Studies on Newly Synthesized Cobalt (II and Nickel (II Complexes with 2-Acetyl Coumarone Semicarbazone and 2-Acetyl Coumarone Thiosemicarbazone

    Directory of Open Access Journals (Sweden)

    Sanjay Goel

    2013-01-01

    Full Text Available Co(II and Ni(II complexes of general composition ML2X2 (M = Co(II, Ni(II; X = Cl−, NO3 − were synthesized by the condensation of metal salts with semicarbazone/thiosemicarbazone derived from 2-acetyl coumarone. The ligands and metal complexes were characterized by NMR, elemental analysis, molar conductance, magnetic susceptibility measurements, IR, and atomic absorption spectral studies. On the basis of electronic, molar conductance and infrared spectral studies, the complexes were found to have square planar geometry. The Schiff bases and their metal complexes were tested for their antibacterial and antioxidant activities.

  12. SPECTROSCOPIC AND BIOLOGICAL STUDIES ON NEWLY SYNTHESIZED COPPER (II AND NICKEL (II COMPLEXES WITH p -DIMETHYLAMINOBANZALDEHYDE SEMICARBAZONE AND p -DIMETHYLAMINOBANZALDEHYDE THIOSEMICARBAZONE

    Directory of Open Access Journals (Sweden)

    Sulekh Chandra

    2012-08-01

    Full Text Available Cu (II and Ni (II complexes of general composition [ML2]X2(M = Cu(II, Ni(II; X = Cl-, NO3- weresynthesized by the condensation of metal salts with semicarbazone / thiosemicarbazone derived from p-dimethylaminobanzaldehyde. The metal complexes were characterized by elemental analysis, molar conductance, magneticsusceptibility measurements, IR and atomic absorption spectral studies. On the basis of electronic and infrared spectralstudies, the metal complexes were found to have tetrahedral geometry. The Schiff bases and their metal complexeswere tested for their antibacterial and antioxidant activities

  13. Spectral characterization of a newly synthesized fluorescent semicarbazone derivative and its usage as a selective fiber optic sensor for copper(II)

    Energy Technology Data Exchange (ETDEWEB)

    Oter, Ozlem [University of Dokuz Eylul, Faculty of Arts and Sciences, Department of Chemistry, 35160 Tinaztepe, Izmir (Turkey); Ertekin, Kadriye [University of Dokuz Eylul, Faculty of Arts and Sciences, Department of Chemistry, 35160 Tinaztepe, Izmir (Turkey)]. E-mail: kadriye.ertekin@deu.edu.tr; Kirilmis, Cumhur [University of Firat, Faculty of Arts and Sciences, Department of Chemistry, 23169 Elazig (Turkey); Koca, Murat [University of Firat, Faculty of Arts and Sciences, Department of Chemistry, 23169 Elazig (Turkey)

    2007-02-19

    In this work photoluminescent properties of highly Cu{sup 2+} selective organic fluoroionophore, semicarbazone derivative; bis(naphtho[2,1-b]furan-2-yl)methanone semicarbazone (BNF) was investigated in different solvents (dichloromethane, tetrahydrofuran, toluene and ethanol) and in polymer matrices of polyvinylchloride (PVC) and ethyl cellulose (EC) by absorption and emission spectrometry. The BNF derivative displayed enhanced fluorescence emission quantum yield, Q {sub f} = 6.1 x 10{sup -2} and molar extinction coefficient, {epsilon} = 29,000 {+-} 65 cm{sup -1} M{sup -1} in immobilized PVC matrix, compared to 2.6 x 10{sup -3} and 24,573 {+-} 115 in ethanol solution. The offered sensor exhibited remarkable fluorescence intensity quenching upon exposure to Cu{sup 2+} ions at pH 4.0 in the concentration range of 1.0 x 10{sup -9} to 3.0 x 10{sup -4} M [Cu{sup 2+}] while the effects of the responding ions (Ca{sup 2+}, Hg{sup +}, Pb{sup 2+}, Al{sup 3+}, Cr{sup 3+}, Mn{sup 2+}, Mg{sup 2+}, Sn{sup 2+}, Cd{sup 2+}, Co{sup 2+} and Ni{sup 2+}) were less pronounced.

  14. A 119Sn Moessbauer Study of Tin(IV) Complexes of 2- and 4-Benzoylpyridine Thiosemicarbazone and 4-Benzoylpyridine Semicarbazone

    International Nuclear Information System (INIS)

    A 119Sn Moessbauer study was carried out of tin(IV) complexes with 2-benzoylpyridine thiosemicarbazone (H2Bz4DH) and its N(4)-methyl (H2Bz4M) and N(4)-phenyl (H2Bz4Ph) derivatives: [Sn(2Bz4DH)Cl3] (1), [Sn(2Bz4DH)PhCl2] (2), [Sn(2Bz4M)Cl3] (3), [H22Bz4M]2[Ph2SnCl4] (4), [Sn(2Bz4Ph)PhCl2] (5), [Sn(2Bz4Ph)Ph2Cl] (6), in which H2Bz4R stands for the neutral ligand and 2Bz4R stands for the anionic thiosemicarbazone. In addition, 119Sn Moessbauer studies of the tin(IV) complexes [Sn(H4Bz4DH)2Cl4H2O] (7), [Sn(H4BzPS)2Cl4H2O] (8) with 4-benzoylpyridine thiosemicarbazone (H4Bz4DH) and the correspondent semicarbazone (H4BzPS) were performed. The isomer shifts decrease upon coordination due to the variation in the percentage of s character as tin changes from approximately sp3 hybridization in the tin salts to sp3d2 in the octahedral or sp3d3 in the heptahedral complexes. The Moessbauer parameters of compound (4) showed the existence of two tin(IV) sites, which have been attributed to the presence of the cis and trans isomers.

  15. Semicarbazone EGA Inhibits Uptake of Diphtheria Toxin into Human Cells and Protects Cells from Intoxication

    Directory of Open Access Journals (Sweden)

    Leonie Schnell

    2016-07-01

    Full Text Available Diphtheria toxin is a single-chain protein toxin that invades human cells by receptor-mediated endocytosis. In acidic endosomes, its translocation domain inserts into endosomal membranes and facilitates the transport of the catalytic domain (DTA from endosomal lumen into the host cell cytosol. Here, DTA ADP-ribosylates elongation factor 2 inhibits protein synthesis and leads to cell death. The compound 4-bromobenzaldehyde N-(2,6-dimethylphenylsemicarbazone (EGA has been previously shown to protect cells from various bacterial protein toxins which deliver their enzymatic subunits from acidic endosomes to the cytosol, including Bacillus anthracis lethal toxin and the binary clostridial actin ADP-ribosylating toxins C2, iota and Clostridium difficile binary toxin (CDT. Here, we demonstrate that EGA also protects human cells from diphtheria toxin by inhibiting the pH-dependent translocation of DTA across cell membranes. The results suggest that EGA might serve for treatment and/or prevention of the severe disease diphtheria.

  16. Chalcones, semicarbazones and pyrazolines as inhibitors of cathepsins B, H and L.

    Science.gov (United States)

    Raghav, Neera; Kaur, Ravinder

    2015-09-01

    Cathepsin B [EC 3.4.22.1], cathepsin H [EC 3.4.22.16] and cathepsin L [EC 3.4.22.15] are the most versatile lysosomal cysteine proteases and are responsible for intracellular protein degradation. These are involved in a number of pathological conditions including tissue degenerative processes. In the present work, we report the synthesis and systematic evaluation of differently substituted chalcones, chalconesemicarbazones, and diarylpyrazolines on cathepsins B, H and L activity. It was found that after a preliminary screening as cysteine protease inhibitors, chalconesemicarbazones were better inhibitors to these cysteine proteases than diarylpyrazolines followed by chalcones. All the synthesized compounds were identified as the best inhibitors to cathepsin L followed by cathepsin B and then cathepsin H. The results are compared with docking studies and it was found that all the compounds resulted in decrease in energy while interacting with the active site of the enzyme. PMID:26193682

  17. Spectral studies on Co(II), Ni(II) and Cu(II) complexes with thiosemicarbazone (L 1) and semicarbazone (L 2) derived from 2-acetyl furan

    Science.gov (United States)

    Chandra, Sulekh; Kumar, Anil

    2007-04-01

    Co(II), Ni(II) and Cu(II) complexes are synthesized with thiosemicarbazone (L 1) and semicarbazone (L 2) derived from 2-acetyl furan. These complexes are characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, mass, IR, electronic and EPR spectral studies. The molar conductance measurements of the complexes in DMSO correspond to non-electrolytic nature except Ni(L) 2(NO 3) 2, which is 1:2 electrolyte. All the complexes are of high-spin type. On the basis of spectral studies an octahedral geometry may be assigned for Co(II) and Ni(II) complexes except nitrato complexes of Ni(II) which is of tetrahedral geometry, whereas tetragonal geometry for Cu(II) complexes.

  18. Expanding the family of heteroleptic oxidovanadium(IV) compounds with salicylaldehyde semicarbazones and polypyridyl ligands showing anti-Trypanosoma cruzi activity.

    Science.gov (United States)

    Scalese, Gonzalo; Benítez, Julio; Rostán, Santiago; Correia, Isabel; Bradford, Lara; Vieites, Marisol; Minini, Lucía; Merlino, Alicia; Coitiño, E Laura; Birriel, Estefania; Varela, Javier; Cerecetto, Hugo; González, Mercedes; Pessoa, João Costa; Gambino, Dinorah

    2015-06-01

    Searching for prospective vanadium-based drugs for the treatment of Chagas disease, a new series of heteroleptic [V(IV)O(L-2H)(NN)] compounds was developed by including the lipophilic 3,4,7,8-tetramethyl-1,10-phenanthroline (tmp) NN ligand and seven tridentate salicylaldehyde semicarbazone derivatives (L1-L7). The compounds were characterized in the solid state and in solution. EPR spectroscopy suggests that the NN ligand is bidentate bound through both nitrogen donor atoms in an axial-equatorial mode. The EPR and (51)V-NMR spectra of aerated solutions at room temperature indicate that the compounds are stable to hydrolysis and that no significant oxidation of V(IV) to V(V) takes place at least in 24h. The complexes are more active in vitro against Trypanosoma cruzi, the parasite responsible for Chagas disease, than the reference drug Nifurtimox and most of them are more active than previously reported [V(IV)O(L-2H)(NN)] complexes of other NN co-ligands. Selectivity towards the parasite was analyzed using J-774 murine macrophages as mammalian cell model. Due to both, high activity and high selectivity, L2, L4, L5 and L7 complexes could be considered new hits for further drug development. Lipophilicity probably plays a relevant role in the bioactivity of the new compounds. The [V(IV)O(L-2H)(NN)] compounds were designed aiming DNA as potential molecular target. Therefore, the novel L1-L7 tmp complexes were screened by computational modeling, comparing their DNA-binding features with those of previously reported [V(IV)O(L-2H)(NN)] compounds with different NN co-ligands. Whereas all the complexes interact well with DNA, with binding modes and strength tuned in different extents by the NN and semicarbazone co-ligands, molecular docking suggests that the observed anti-T. cruzi activity cannot be explained upon DNA intercalation as the sole mechanism of action. PMID:25824466

  19. Crystal structures of copper(II) nitrate, copper(II) chloride, and copper(II) perchlorate complexes with 2-formylpyridine semicarbazone

    International Nuclear Information System (INIS)

    Compounds dinitrato(2-formylpyridinesemicarbazone)copper (I), dichloro(2-formylpyridinesemicarbazone) copper hemihydrate (II), and bis(2-formylpyridinesemicarbazone)copper(2+) perchlorate hydrate (III) are synthesized and their crystal structures are determined. In compounds I-III, the neutral 2-formylpyridine semicarbazone molecule (L) is tridentately attached to the copper atom via the N,N,O set of donor atoms. In compounds I and II, the Cu: L ratio is equal to 1: 1, whereas, in III, it is 1: 2. In complex I, the coordination sphere of the copper atom includes two nitrate ions with different structural functions in addition to the L ligand. The structure is built as a one-dimensional polymer in which the NO3 bidentate group fulfills a bridging function. The coordination polyhedron of the copper(2+) atom can be considered a distorted tetragonal bipyramid (4 + 1 + 1). Compound II has an ionic structure in which the main element is the [CuLCl2 . Cu(H2O)LCl]+ dimer. In the dimer, the copper atoms are linked via one of the μ2-bridging chlorine atoms. The coordination polyhedra of the central atoms of the Cu(H2)LCl and CuLCl2 complex fragments are tetragonal bipyramid and tetragonal pyramid, respectively. In compound III, the copper atom is octahedrally surrounded by two L ligands in the mer configuration.

  20. Metal complexes of a pentadentate N2O3bis(semicarbazone) Schiff-base. A case study of structure-spectroscopy correlation

    Science.gov (United States)

    Inoue, Mayara Hissami; Ribeiro, Ronny Rocha; Sabino, José Ricardo; Nunes, Fábio Souza

    2016-07-01

    Schiff condensation of 2,6-diformyl 4-methylphenol with semicarbazide hydrochloride in 1:2 molar ratio produces the bis(semicarbazone) ligand, herein called H3L. A comprehensive spectroscopic analysis of the compound was performed by 1H and 13C NMR, FTIR and electronic spectroscopies. Assignments to the UV-vis spectrum of H3L were supported by semi-empirical quantum mechanics ZINDO/S calculations. The ligand H3L forms monoclinic crystals in the space group P21/c and its structure is stabilized by classic hydrogen bonds with propanone molecules. It promptly reacts with first row metal ions to produce the following coordination compounds: [Co2(L)(μ-NO3)]·DMF, [Ni2(H2L)(μ-CH3COO)(CH3COO)2]·2H2O, [Cu2(L)(μ-NO3)(H2O)2]·H2O, [Cu2(L)(μ-CH3COO)(H2O)2]·H2O and [Cu2(H2L)(μ-Cl)Cl2]·3H2O, that have different compositions, depending on the degree of deprotonation of the ligand upon coordination. Electronic and EPR spectroscopies as well as effective magnetic moment measurements of the complexes were used in an attempt to better understand their mode of coordination, the microsymmetry around the metal ions and magnetic properties.

  1. Crystal structures of copper(II) nitrate, copper(II) chloride, and copper(II) perchlorate complexes with 2-formylpyridine semicarbazone

    Science.gov (United States)

    Chumakov, Yu. M.; Tsapkov, V. I.; Antosyak, B. Ya.; Bairac, N. N.; Simonov, Yu. A.; Bocelli, G.; Pahontu, E.; Gulea, A. P.

    2009-05-01

    Compounds dinitrato(2-formylpyridinesemicarbazone)copper ( I), dichloro(2-formylpyridinesemicarbazone) copper hemihydrate ( II), and bis(2-formylpyridinesemicarbazone)copper(2+) perchlorate hydrate ( III) are synthesized and their crystal structures are determined. In compounds I- III, the neutral 2-formylpyridine semicarbazone molecule ( L) is tridentately attached to the copper atom via the N,N,O set of donor atoms. In compounds I and II, the Cu: L ratio is equal to 1: 1, whereas, in III, it is 1: 2. In complex I, the coordination sphere of the copper atom includes two nitrate ions with different structural functions in addition to the L ligand. The structure is built as a one-dimensional polymer in which the NO3 bidentate group fulfills a bridging function. The coordination polyhedron of the copper(2+) atom can be considered a distorted tetragonal bipyramid (4 + 1 + 1). Compound II has an ionic structure in which the main element is the [Cu LCl2 · Cu(H2O) LCl]+ dimer. In the dimer, the copper atoms are linked via one of the μ2-bridging chlorine atoms. The coordination polyhedra of the central atoms of the Cu(H2) LCl and Cu LCl2 complex fragments are tetragonal bipyramid and tetragonal pyramid, respectively. In compound III, the copper atom is octahedrally surrounded by two L ligands in the mer configuration.

  2. Crystal structures of copper(II) nitrate, copper(II) chloride, and copper(II) perchlorate complexes with 2-formylpyridine semicarbazone

    Energy Technology Data Exchange (ETDEWEB)

    Chumakov, Yu. M. [Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of); Tsapkov, V. I. [State University of Moldova (Moldova, Republic of); Antosyak, B. Ya. [Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of); Bairac, N. N. [State University of Moldova (Moldova, Republic of); Simonov, Yu. A., E-mail: simonov.xray@phys.asm.md [Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of); Bocelli, G. [National Research Council (IMEM-CNR), Institute of Materials for Electronics and Magnetism (Italy); Pahontu, E. [University of Medicine and Pharmacy (Romania); Gulea, A. P. [State University of Moldova (Moldova, Republic of)

    2009-05-15

    Compounds dinitrato(2-formylpyridinesemicarbazone)copper (I), dichloro(2-formylpyridinesemicarbazone) copper hemihydrate (II), and bis(2-formylpyridinesemicarbazone)copper(2+) perchlorate hydrate (III) are synthesized and their crystal structures are determined. In compounds I-III, the neutral 2-formylpyridine semicarbazone molecule (L) is tridentately attached to the copper atom via the N,N,O set of donor atoms. In compounds I and II, the Cu: L ratio is equal to 1: 1, whereas, in III, it is 1: 2. In complex I, the coordination sphere of the copper atom includes two nitrate ions with different structural functions in addition to the L ligand. The structure is built as a one-dimensional polymer in which the NO{sub 3} bidentate group fulfills a bridging function. The coordination polyhedron of the copper(2+) atom can be considered a distorted tetragonal bipyramid (4 + 1 + 1). Compound II has an ionic structure in which the main element is the [CuLCl{sub 2} . Cu(H{sub 2}O)LCl]{sup +} dimer. In the dimer, the copper atoms are linked via one of the {mu}{sub 2}-bridging chlorine atoms. The coordination polyhedra of the central atoms of the Cu(H{sub 2})LCl and CuLCl{sub 2} complex fragments are tetragonal bipyramid and tetragonal pyramid, respectively. In compound III, the copper atom is octahedrally surrounded by two L ligands in the mer configuration.

  3. Inner complexes of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Be(II) and dioxouranium(VI) with salicylaldehyde semicarbazone

    Energy Technology Data Exchange (ETDEWEB)

    Maurya, P.L.; Agarwala, B.V.; Dey, A.K. (Allahabad Univ. (India). Dept. of Chemistry)

    1980-08-01

    Salicylaldehyde semicarbazone (SALSC), yields complexes, ML/sub 2/.2H/sub 2/O (M = Co(II), Ni(II), Cu(II), Zn(II) and Cd(II)) and ML/sub 2/ (M = Be(II) and UO/sub 2/(VI)). The complexes have been characterized by analytical, spectral, magnetic and thermogravimetric studies. SALSC acts as a singly negatively charged bidentate anion, and two such anions coordinate to the metal ion through the hydroxyl oxygen and nitrogen of the C = N group yielding a neutral chelate. The complexes of Co(II), Ni(II) and Cu(II) are paramagnetic with magnetic moment values 4.93, 3.35 and 1.98 BM, respectively. The magnetic and spectral data suggest octahedral geometry of Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and UO/sub 2/(VI) complexes, whereas the Be(II) complex is tetrahedral. TG study reveals the order of thermal stability as : Zn(II) approximately equal to Ni(II) >Be(II) approximately equal to Cd(II) > UO/sub 2/(VI) approximately equal to Co(II) approximately equal to Cu(II).

  4. New approach towards the synthesis of selenosemicarbazones, useful compounds for Chagas' disease.

    Science.gov (United States)

    Pizzo, Chiara; Faral-Tello, Paula; Yaluff, Gloria; Serna, Elva; Torres, Susana; Vera, Ninfa; Saiz, Cecilia; Robello, Carlos; Mahler, Graciela

    2016-02-15

    Herein, we describe a new approach towards the synthesis of selenosemicarbazones. The reaction involves an O-Se exchange of semicarbazones using Ishihara reagent. Eleven selenosemicarbazones were prepared using this methodology, with low to moderate yields. Among the prepared compounds the m-bromo phenyl methyl derivative 1b was selected to be evaluated in vivo, in a murine model of acute Chagas' disease. Compound 1b 10 mg/kg bw/day reduced 50% of parasitaemia profile compared with the control group, but was less effective than Benznidazole (50 mg/kg bw/day reduced 90%) and toxic. These studies are important to guide future Chagas drug design. PMID:26774036

  5. Lanthanide(III) complexes of bis-semicarbazone and bis-imine-substituted phenanthroline ligands: solid-state structures, photophysical properties, and anion sensing.

    Science.gov (United States)

    Nadella, Sandeep; Selvakumar, Paulraj M; Suresh, Eringathodi; Subramanian, Palani S; Albrecht, Markus; Giese, Michael; Fröhlich, Roland

    2012-12-21

    Phenanthroline-based hexadentate ligands L(1) and L(2) bearing two achiral semicarbazone or two chiral imine moieties as well as the respective mononuclear complexes incorporating various lanthanide ions, such as La(III), Eu(III), Tb(III), Lu(III), and Y(III) metal ions, were synthesized, and the crystal structures of [ML(1)Cl(3)] (M=La(III), Eu(III), Tb(III), Lu(III), or Y(III)) complexes were determined. Solvent or water molecules act as coligands for the rare-earth metals in addition to halide anions. The big Ln(III) ion exhibits a coordination number (CN) of 10, whereas the corresponding Eu(III), Tb(III), Lu(III), and Y(III) centers with smaller ionic radii show CN=9. Complexes of L(2), namely [ML(2)Cl(3)] (M=Eu(III), Tb(III), Lu(III), or Y(III)) ions could also be prepared. Only the complex of Eu(III) showed red luminescence, whereas all the others were nonluminescent. The emission properties of the Eu derivative can be applied as a photophysical signal for sensing various anions. The addition of phosphate anions leads to a unique change in the luminescence behavior. As a case study, the quenching behavior of adenosine-5'-triphosphate (ATP) was investigated at physiological pH value in an aqueous solvent. A specificity of the sensor for ATP relative to adenosine-5'-diphosphate (ADP) and adenosine-5'-monophosphate (AMP) was found. (31)P NMR spectroscopic studies revealed the formation of a [EuL(2)(ATP)] coordination species.

  6. A {sup 119}Sn Moessbauer Study of Tin(IV) Complexes of 2- and 4-Benzoylpyridine Thiosemicarbazone and 4-Benzoylpyridine Semicarbazone

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Rebolledo, Anayive [Universidade Federal de Minas Gerais, Departamento de Quimica (Brazil); Ardisson, Jose D., E-mail: jdr@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear, Laboratorio de Fisica Aplicada (LFA/CDTN) (Brazil); Lima, Geraldo M. de [Universidade Federal de Minas Gerais, Departamento de Quimica (Brazil); Macedo, Waldemar A. A. [Centro de Desenvolvimento da Tecnologia Nuclear, Laboratorio de Fisica Aplicada (LFA/CDTN) (Brazil); Beraldo, Heloisa, E-mail: hberaldo@ufmg.br [Universidade Federal de Minas Gerais, Departamento de Quimica (Brazil)

    2005-06-15

    A {sup 119}Sn Moessbauer study was carried out of tin(IV) complexes with 2-benzoylpyridine thiosemicarbazone (H2Bz4DH) and its N(4)-methyl (H2Bz4M) and N(4)-phenyl (H2Bz4Ph) derivatives: [Sn(2Bz4DH)Cl{sub 3}] (1), [Sn(2Bz4DH)PhCl{sub 2}] (2), [Sn(2Bz4M)Cl{sub 3}] (3), [H{sub 2}2Bz4M]{sub 2}[Ph{sub 2}SnCl{sub 4}] (4), [Sn(2Bz4Ph)PhCl{sub 2}] (5), [Sn(2Bz4Ph)Ph{sub 2}Cl] (6), in which H2Bz4R stands for the neutral ligand and 2Bz4R stands for the anionic thiosemicarbazone. In addition, {sup 119}Sn Moessbauer studies of the tin(IV) complexes [Sn(H4Bz4DH){sub 2}Cl{sub 4}H{sub 2}O] (7), [Sn(H4BzPS){sub 2}Cl{sub 4}H{sub 2}O] (8) with 4-benzoylpyridine thiosemicarbazone (H4Bz4DH) and the correspondent semicarbazone (H4BzPS) were performed. The isomer shifts decrease upon coordination due to the variation in the percentage of s character as tin changes from approximately sp{sup 3} hybridization in the tin salts to sp{sup 3}d{sup 2} in the octahedral or sp{sup 3}d{sup 3} in the heptahedral complexes. The Moessbauer parameters of compound (4) showed the existence of two tin(IV) sites, which have been attributed to the presence of the cis and trans isomers.

  7. A 119Sn Mössbauer Study of Tin(IV) Complexes of 2- and 4-Benzoylpyridine Thiosemicarbazone and 4-Benzoylpyridine Semicarbazone

    Science.gov (United States)

    Pérez-Rebolledo, Anayive; Ardisson, José D.; de Lima, Geraldo M.; Macedo, Waldemar A. A.; Beraldo, Heloisa

    2005-06-01

    A 119Sn Mössbauer study was carried out of tin(IV) complexes with 2-benzoylpyridine thiosemicarbazone (H2Bz4DH) and its N(4)-methyl (H2Bz4M) and N(4)-phenyl (H2Bz4Ph) derivatives: [Sn(2Bz4DH)Cl3] (1), [Sn(2Bz4DH)PhCl2] (2), [Sn(2Bz4M)Cl3] (3), [H22Bz4M]2[Ph2SnCl4] (4), [Sn(2Bz4Ph)PhCl2] (5), [Sn(2Bz4Ph)Ph2Cl] (6), in which H2Bz4R stands for the neutral ligand and 2Bz4R stands for the anionic thiosemicarbazone. In addition, 119Sn Mössbauer studies of the tin(IV) complexes [Sn(H4Bz4DH)2Cl4H2O] (7), [Sn(H4BzPS)2Cl4H2O] (8) with 4-benzoylpyridine thiosemicarbazone (H4Bz4DH) and the correspondent semicarbazone (H4BzPS) were performed. The isomer shifts decrease upon coordination due to the variation in the percentage of s character as tin changes from approximately sp3 hybridization in the tin salts to sp3d2 in the octahedral or sp3d3 in the heptahedral complexes. The Mössbauer parameters of compound (4) showed the existence of two tin(IV) sites, which have been attributed to the presence of the cis and trans isomers.

  8. Synthesis, characterization, DNA interaction, antioxidant and anticancer activity of new ruthenium(II) complexes of thiosemicarbazone/semicarbazone bearing 9,10-phenanthrenequinone.

    Science.gov (United States)

    Anitha, Panneerselvam; Chitrapriya, Nataraj; Jang, Yoon Jung; Viswanathamurthi, Periasamy

    2013-12-01

    A new series of octahedral ruthenium(II) complexes supported by tridentate ligands derived from phenanthrenequinone and derivatives of thiosemicarbazide/semicarbazide and other co-ligands have been synthesized and characterized. DNA binding experiments indicated that ruthenium(II) complexes can interact with DNA through non-intercalation and the apparent binding constant value (Kb) of [RuCl(CO)(PPh₃)(L₃)] (3) at room temperature was calculated to be 2.27 × 10(3)M(-1). The DNA cleavage studies showed that the complexes have better cleavage of pBR 322 DNA. Antioxidative activity proved that the complexes have significant radical scavenging activity against free radicals. Cytotoxic activities showed that the ruthenium(II) complexes exhibited more effective cytotoxic activity against selected cancer cells. PMID:24144689

  9. SYNTHESIS, SPECTRAL CHARACTERIZATION OF Mn(II AND Co(II COMPLEXES WITH THIOSEMICARBAZONES AND SEMICARBAZONES DERIVED FROM PYRIDINE-2- CARBOXALDEHYDE

    Directory of Open Access Journals (Sweden)

    Sulekh Chandra

    2014-02-01

    Full Text Available Mn(II and Co(II complexes are synthesized with L1(Pyridine-2-carboxaldehydethiosemicarbazones and L2 (Pyridne-2-carboxaldehydesemicarbazones. These complexes were characterized by elemental analysis, molar conductance measurements, magnetic suscepectibility measurements, mass, IR, electronic and EPR spectral studies. The molar conductance measurement of the complexes in DMSO corresponds to non electrolytes nature with L1 and formulated as [M(L2X2] where M=Mn(II and Co(II complexes. The molar conductance measurements with L2 lie in the range 208-217 Ω-1cm2mol-1 indicating the electrolytes nature of the complexes thus the complexes formulated as [M(L2]X2 where M=Mn(II and Co(II complexes. On the basis of spectral studies an octahedral geometry has been assigned for Mn(II and Co(II complexes.

  10. SYNTHESIS, SPECTRAL CHARACTERIZATION OF Mn(II) AND Co(II) COMPLEXES WITH THIOSEMICARBAZONES AND SEMICARBAZONES DERIVED FROM PYRIDINE-2- CARBOXALDEHYDE

    OpenAIRE

    Sulekh Chandra; Prem Ballabh

    2014-01-01

    Mn(II) and Co(II) complexes are synthesized with L1(Pyridine-2-carboxaldehydethiosemicarbazones) and L2 (Pyridne-2-carboxaldehydesemicarbazones). These complexes were characterized by elemental analysis, molar conductance measurements, magnetic suscepectibility measurements, mass, IR, electronic and EPR spectral studies. The molar conductance measurement of the complexes in DMSO corresponds to non electrolytes nature with L1 and formulated as [M(L)2X2] where M=Mn(II) and Co(II) complexes. The...

  11. 超声辅助丙酮缩氨基脲的合成%Synthesis of acetone semicarbazone under ultrasonic irradiation

    Institute of Scientific and Technical Information of China (English)

    张玉全; 盖轲

    2012-01-01

    目的 研究一种方便、快速合成丙酮缩氨基脲(AS)的方法.方法 以盐酸氨基脲和丙酮为原料,室温下超声辐射协助合成丙酮缩氨基脲.考察原料配比、超声辐射频率和反应时间对反应产率的影响.结果 在最佳反应条件下(nSHC:nacetone=1∶10,超声频率59 kHz,反应时间40 min)合成了丙酮缩氨基脲,收率可达85%.结论 此法与常规的加热反应法相比,反应时间短,产物收率高,操作简单.

  12. Synthesis of New Substituted Crown Ether and its Concentrated Semicarbazone Compounds%新取代冠醚及其缩氨脲化合物的合成

    Institute of Scientific and Technical Information of China (English)

    张来新; 杨琼

    2006-01-01

    报道了在多聚磷酸作用下,在75℃下将苯并-18-冠-6用丙烯酸酰化环合,反应2 h,合成了茚满酮-[1]-5,6-苯并-18-冠-6(A),其收率为30%.后以乙醇为溶剂,以(A)和氨基脲为反应物,用醋酸和醋酸钠调节PH为3~4,在80℃左右反应4h,合成了茚满酮-[1]-缩氨基脲-5,6-苯并-18-冠-6(B),其收率为56%.经由IR,MS和元素分析对合成的二种新物质的结构进行了鉴定.

  13. Study on Synthesis of a Medicine Intermediate-Acetone Semicarbazone%医药中间体丙酮缩氨基脲合成研究

    Institute of Scientific and Technical Information of China (English)

    杨琼; 周丹丹

    2007-01-01

    以盐酸氨基脲、丙酮为原料,直接反应合成了医药中间体丙酮缩氨基脲;分别研究了反应温度、反应时间、原料配比等条件对合成反应的影响,从而确定了最佳工艺条件;用该方法合成丙酮缩氨基脲的最佳工艺条件是:盐酸氨基脲和丙酮反应温度为52℃;反应时间为1.5h;n(盐酸氨基脲):n(丙酮)=1∶7;丙酮缩氨基脲的收率达到63.98%.

  14. 微波辐射合成苯甲醛缩氨基脲的研究%Synthesis of Benzaldehyde Semicarbazone under Microwave Irradiation

    Institute of Scientific and Technical Information of China (English)

    李丕高; 魏颖; 孙长治

    2009-01-01

    在微波辐射条件下, 以水合肼、尿素和苯甲醛为原料,采用一釜两步法合成了苯甲醛缩氨基脲.通过单因素实验研究了反应物摩尔比、微波辐射功率、辐射时间等因素对苯甲醛缩氨基脲收率的影响.结果表明, 微波辐射可以促进苯甲醛缩氨基脲的合成, 在优化的合成条件下,即n(水合肼):n(尿素):n(苯甲醛)= 1:2.5:1.1,水合肼与尿素反应的微波辐射功率为500 W、反应温度为101℃、微波辐射时间为20 min,氨基脲和苯甲醛反应的微波辐射功率为500 W、反应温度为80℃、微波辐射时间为20 min时,苯甲醛缩氨基脲的收率可达85.28%.

  15. Study on Synthesis of a Medicine Intermediate——Acetone Semicarbazone%医药中间体丙酮缩氨基脲合成研究

    Institute of Scientific and Technical Information of China (English)

    王树清; 高崇

    2006-01-01

    以水合肼、尿素、丙酮为原料,直接反应合成丙酮缩氨基脲,分别研究了反应温度、反应时间、原料配比、溶剂用量等条件对合成反应的影响,确定了最佳工艺条件.该方法合成丙酮缩氨基脲的最佳工艺条件是:水合肼和尿素反应温度100℃,反应时间7 h;氨基脲与丙酮反应温度55℃,反应时间2 h;n(水合肼):n(尿素):n(丙酮)=1:1.6:3.丙酮缩氨基脲的收率达到97.19%,产品纯度达到98.5%.

  16. Electronic, epr and magnetic studies of Co(II), Ni(II) and Cu(II) complexes with thiosemicarbazone (L 1) and semicarbazone (L 2) derived from pyrole-2-carboxyaldehyde

    Science.gov (United States)

    Chandra, Sulekh; Kumar, Anil

    2007-07-01

    Co(II), Ni(II) and Cu(II) complexes are synthesized with thiosemicarbazone (L 1) and semicarbazone (L 2) derived from pyrole-2-carboxyaldehyde. These complexes are characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, mass, IR, electronic and EPR spectral studies .The molar conductance measurements of the complexes in DMSO correspond to non-electrolytic nature except Co(L 1) 2(NO 3) 2 and Ni(L 1) 2(NO 3) 2 complexes which are 1:2 electrolytes. All the complexes are of high-spin type. On the basis of spectral studies an octahedral geometry may be assigned for Co(II) and Ni(II) complexes except Co(L 1) 2(NO 3) 2 and Ni(L 1) 2(NO 3) 2 which are of tetrahedral geometry. A tetragonal geometry may be suggested for Cu(II) complexes.

  17. Benzaldehyde thio­semicarbazone

    OpenAIRE

    Xiu-Ping Ju; Ji-Dong Zhang; Yan Qiao; Lingqian Kong

    2008-01-01

    The title compound, C8H9N3S, contains two molecules in the asymmetric unit. One molecule is close to being planar (r.m.s. deviation from the mean plane = 0.06 Å for the non-H atoms), while the other exhibits a dihedral angle of 21.7 (1)° between the benzene ring and the mean plane of the thiosemicarbazone unit. Intermolecular N—H...S hydrogen bonds link the molecules into layers parallel to the (010) plane.

  18. Synthesis and characterization of dioxouranium (VI) complexes of Schiff bases derived from isatin, isovanillin and o-vanillin

    International Nuclear Information System (INIS)

    Three Schiff bases viz. isatin semicarbazone, isovanillin thiosemicarbazone, o-vanillin para-anisidine and their dioxouranium (VI) complexes have been synthesised and characterized by elemental analysis, IR and NMR spectral studies. (author). 19 refs., 1 tab

  19. Synthèse, caractérisation structurale de complexes de thiosemicarbazones, semicarbazones et oximes mono et bifonctionnelles d'aldéhydes thiophéniques avec des métaux de transition. Etude de propriétés biologiques.

    OpenAIRE

    Alomar, Kusai

    2012-01-01

    Les thiosemicarbazones, les semicarbazones et les oximes du thiophène-3-carboxaldéhyde et du thiophène-2,3-dicarboxaldéhyde réagissent avec les chlorures et/ou bromures de cobalt(II), nickel(II), cuivre(II), zinc(II) et cadmium(II) pour conduire à diverses espèces complexes. Les structures des ligands et des complexes ont été déterminées principalement par cristallographie et par spectroscopie infrarouge. Leurs propriétés antifongiques ont été testées vis à vis de trois souches : Candida albi...

  20. Microwave assisted synthesis, spectroscopic, electrochemical and DNA cleavage studies of lanthanide(III) complexes with coumarin based imines

    Science.gov (United States)

    Kapoor, Puja; Fahmi, Nighat; Singh, R. V.

    2011-12-01

    The present work stems from our interest in the synthesis, characterization and biological evaluation of lanthanide(III) complexes of a class of coumarin based imines which have been prepared by the interaction of hydrated lanthanide(III) chloride with the sodium salts of 3-acetylcoumarin thiosemicarbazone (ACTSZH) and 3-acetylcoumarin semicarbazone (ACSZH) in 1:3 molar ratio using thermal as well as microwave method. Characterization of the ligands as well as the metal complexes have been carried out by elemental analysis, melting point determinations, molecular weight determinations, magnetic moment, molar conductance, IR, 1H NMR, 13C NMR, electronic, EPR, X-ray powder diffraction and mass spectral studies. Spectral studies confirm ligands to be monofunctional bidentate and octahedral environment around metal ions. The redox behavior of one of the synthesized metal complex was investigated by cyclic voltammetry. Further, free ligands and their metal complexes have been screened for their antimicrobial as well as DNA cleavage activity. The results of these findings have been presented and discussed.

  1. 无催化剂条件下一锅法合成缩氨基脲的研究%Synthesis of Semicarbazone by One-Pot Method under Catalyst-free Condition

    Institute of Scientific and Technical Information of China (English)

    孙孟展

    2007-01-01

    不使用催化剂,在离子液体、超声波、微波辐射、水相、无溶剂、水相微波辐射条件下,采用一锅法合成一系列取代苯甲醛缩氨基脲及杂环醛缩氨基脲.该绿色合成方法反应时间短,收率高,后处理简单,对环境友好.

  2. Synthesis and Characterization of 5-methyl-isatin-3-semicarbazone Fe(Ⅲ) Complex%5-甲基靛红-3-缩氨基脲Fe(Ⅲ)的合成与表征

    Institute of Scientific and Technical Information of China (English)

    陈刚; 汤颖; 高月泉; 邓强; 张群正

    2009-01-01

    以对甲基苯胺为原料经两步反应合成了5-甲基靛红,进而与氨基脲缩合得到5-甲基靛红-3-缩氨基脲,以此为配体与FeEl3作用合和成了其配位化合物,通过元素分析、红外光谱对该配合物进行了表征,并推断了可能的结构.

  3. Synthesis and Characterization of Isatin 3-semicarbazone Transition Metal Complexes%靛红-3-缩氨基脲过渡金属配合物的合成与表征

    Institute of Scientific and Technical Information of China (English)

    马超; 汤颖; 吴亚; 苗延青; 陈刚

    2009-01-01

    以靛红和氨基脲为原料经缩合反应合成了靛红-3-缩氨基脲(L),以此为配体分别与Tj(Ⅲ)、Fe(Ⅲ)、Ce(Ⅲ)、ZrO(Ⅱ)作用合成了其配位化合物,通过元素分析、红外光谱对配体和配合物进行了表征,并推断了可能的结构.

  4. Synthesis and Structure of the Semicarbazone Compounds Containing Pyrazolone-ring%含吡唑啉酮氨基脲类化合物的合成及结构

    Institute of Scientific and Technical Information of China (English)

    刘广飞; 刘浪; 贾殿赠; 王淑华; 许贯诚; 郁开北

    2004-01-01

    以1-苯基-3-甲基-吡唑啉酮-5 (PMP)和1,3-二苯基-吡唑啉酮-5 (DPP)为原料合成了六种4-酰基吡唑啉酮,并分别与氨基脲缩合,得到六个新的含吡唑啉酮环的缩氨基脲类化合物.用IR, 1H NMR和13C NMR对各化合物进行了表征及结构确证,并用X射线单晶衍射法测定了化合物1c [1-苯基-3-甲基-4-丙酰基-吡唑啉酮-5缩氨基脲(PMPP-SC)]的晶体结构.

  5. 5-甲基靛红-3-缩氨基脲Ce(Ⅲ)的合成与表征%Synthesis and Characterization of 5-methyl-isatin-3-semicarbazone Ce(Ⅲ) Complex

    Institute of Scientific and Technical Information of China (English)

    黄芳; 徐红梅; 薛蒙伟

    2012-01-01

    以5-甲基靛红和氨基脲为原料,进行缩合反应得到得到5-甲基靛红-3-缩氨基脲,以此为配体与Ce(NO3)3作用合成了其配位化合物,通过红外光谱、元素分析对该配合物进行了表征,推断了可能的结构.

  6. Synthesis and Characterization of Aromatic Aldehyde N-2,3,4,6-tetra-O-acetyl-β-D-glucopyranosyl Semicarbazones%含葡萄糖基团缩氨基硫脲Schiff Base的合成

    Institute of Scientific and Technical Information of China (English)

    曹克广; 王忠刚

    2002-01-01

    本论文以2,3,4,6-四-O-乙酰基-β-D-吡喃葡萄糖基异硫氰酸酯为原料,制得了8个未见报道的含葡萄糖基硫脲基Schiff base(希夫碱类化合物):芳香醛缩N-氨基-N'-2',3',4',6'-四-O-乙酰基-β-D-吡喃葡萄糖基硫脲,所有目标化合物均经IR,1HNMR进行了表征.

  7. Synthesis and Biological Activity of Benzophenonehydrazone Derivatives Containing Semicarbazone Structure%含缩氨基脲结构的二苯甲酮腙衍生物的合成与生物活性

    Institute of Scientific and Technical Information of China (English)

    刘永榜; 彭伟立; 郁林军; 邢家华; 陈杰; 夏旭建; 沈德隆

    2010-01-01

    以对硝基苯甲酰氯、卤代苯、甲烷磺酰氯、水合肼等为原料合成4-肉代-N-甲基-4'-甲烷磺酰氨基二苯甲酮腙,后者与苯基异氰酸酯反应得到23种含缩氨基脲结构的二苯甲酮腙新型化合物.对所得化合物结构均经'H NMR和MS表征;初步生物活性测试表明这些化合物具有良好的杀虫活性.

  8. Benzaldehyde thio­semicarbazone monohydrate

    OpenAIRE

    Sheng-Jiu Gu; Kai-Mei Zhu

    2008-01-01

    In the title compound, C8H9N3S·H2O, intramolecular N—H...N hydrogen bonding contributes to the molecular conformation. Water molecules are involved in intermolecular N—H...O and O—H...S hydrogen bonds, which link the molecules into ribbons extended along the a axis. Weak intermolecular N—H...S hydrogen bonds link these ribbons into layers parallel to the ab plane with the phenyl rings pointing up and down.

  9. (E-2-Hydroxynaphthalene-1-carbaldehyde semicarbazone

    Directory of Open Access Journals (Sweden)

    Yu-Peng Tian

    2009-05-01

    Full Text Available The title compound, C12H11N3O2, adopts an E or trans configuration with respect to the C=N bond. There is an intramolecular O—H...N hydrogen bond involving the hydroxyl H atom and an N atom of the hydrazine group. In the crystal structure, molecules are connected via N—H...O hydrogen bonds, forming a three-dimensional network.

  10. Organic Synthesis

    OpenAIRE

    Romea, Pedro

    2014-01-01

    Organic Synthesis is a one-semester course of the fourth year of the Chemistry Degree at the Universitat de Barcelona. This course covers the most important transformations in Organic Chemistry, including a short introduction to the Retrosynthetic Analysis. The aim is to provide a solid knowledge of the main reactions and their mechanism, which could later be improved during Master studies.

  11. Evaluation of flux synthesis algorithms

    International Nuclear Information System (INIS)

    The flux synthesis algorithm which is the best fit to the numerical solution of the multigroup diffusion equations, was determined. Three different types of synthesis were studied: 1) discontinuous synthesis 2) continuous synthesis 3) pseudo-continuous synthesis. A matrix and a differential formulation were developed for the first two types of synthesis. For pseudo-continuous synthesis only the matrix formulation was used. Some tests were performed and the results allowed us to establish the following order of efficiency for the algorithms: 1) continuous synthesis (matrix formulation) 2) continuous synthesis (differential formulation) 3) pseudo-continuous synthesis 4) discontinuous synthesis (matrix formulation) 5) discontinuous synthesis (differential formulation). (Author)

  12. Overall Synthesis

    International Nuclear Information System (INIS)

    AMIGO is an OECD/NEA international project on the topic of 'Approaches and Methods for Integrating Geological Information in the Safety Case'. The term safety case here refers to the post-closure safety case for a geological repository for long-lived radioactive waste, and is defined as a synthesis of evidence, analyses and arguments that quantify and substantiate a claim that the repository is safe. Geological or geo-scientific information includes the various types of geophysical, hydrogeological, geochemical and structural information that can contribute to the safety case. The safety case is generally updated periodically throughout the step-wise process of repository siting, planning, construction, operation, as well as prior to closure, and becomes more rigorous over time, as increasing amounts of geological and other data become available, until, for a well-chosen site and design, a point is reached at which the safety case is adequate for repository licensing. AMIGO is structured as a series of workshops. This document summarises the first workshop of the AMIGO series, held at Yverdon-les-Bains, Switzerland, on 3-5 June 2003, a-nd-hosted The focus of the workshop was on 'building confidence (in analyses and arguments that support the safety case) using multiple lines of evidence', but other themes within the overall scope of AMIGO were also discussed, such as the integration of the work of geo-scientists and safety assessors. The main themes addressed by the workshop, which include the topics covered by the Working Group Sessions, can be stated as follows: the role of the geosphere in disposal concepts; the ways in which geological information is used by waste management programmes, and the way in which usage changes as a programme progresses; the synthesis of wide ranging geo-scientific information into a consistent site description or conceptual model; the development of arguments for the long-term safety of disposal systems; the use of multiple lines of

  13. Synthesis and Characterization of Cobalt(II, Nickel(II and Copper(II Complexes with Nitrogen-Oxygen Donor Ligand

    Directory of Open Access Journals (Sweden)

    B. K. Rai

    2014-09-01

    Full Text Available The complexes of ML2 were synthesized where M= Co(II, Ni(II and Cu(II and L= 2-Butyl thioquinazoline 4 (3H- semicarbazone (BTQS. The ligand have been synthesized by condensation of thioquinazoline-4(3H-one with semicarbazide hydrochlande characterized by molar mass, elemental analysis, Infrared spectra, electronic spectra, magnetic susceptibility and molar conductance measurements .The ligand BTQS acts as neutral bidentate chelating agent and coordinated to metal ions through azomethine nitrogen and carbonyl oxygen of semicarbazone moiety. The remaining Coordination centres are satisfied by anions such as Cl-, Br-, I- and NO3-.

  14. Synthesis and Characterization of Cu(II, Ni(II And Co(II Coordination Compounds with Nitrogen and Oxygen Containing Schiff Base

    Directory of Open Access Journals (Sweden)

    Rajeshwar Rai

    2014-03-01

    Full Text Available Octahedral complexes has been designed and synthesized by a 2-propyl-thioquinozoline 4(3H semicarbazone (PTQS with Co(II, Ni(II and Cu(II metal ions. The complexes was characterized by molar mass, elemental analyses, IR electronic spectra, Molar conductivity and magnetic susceptibility assistance. On the above studies it was confirming that metal ions was coordinated with Carbonyl oxygen and azomethine nitrogen atom of semicarbazone moiety. The remaining valency of metal ions are satisfied by negative ions such as Cl–, Br–, I– and No3– ions.

  15. Substructural controller synthesis

    Science.gov (United States)

    Su, Tzu-Jeng; Craig, Roy R., Jr.

    1989-01-01

    A decentralized design procedure which combines substructural synthesis, model reduction, decentralized controller design, subcontroller synthesis, and controller reduction is proposed for the control design of flexible structures. The structure to be controlled is decomposed into several substructures, which are modeled by component mode synthesis methods. For each substructure, a subcontroller is designed by using the linear quadratic optimal control theory. Then, a controller synthesis scheme called Substructural Controller Synthesis (SCS) is used to assemble the subcontrollers into a system controller, which is to be used to control the whole structure.

  16. Synthesis of Steroidal Thiadiazoles from Steroidal Ketones

    Directory of Open Access Journals (Sweden)

    M. Akhtar

    2005-08-01

    Full Text Available Syntheses of steroidal heterocycles containing a five-membered N,S- heterocycle attached at the 6,7 positions of the B ring are reported. 5α-Cholestane-6-one (1, its 3β-acetoxy- (2 and 3β-chloro- (3 analogues reacted with semicarbazide and aqueous sodium acetate in refluxing ethanol to yield 5α-cholestan-6-one-semicarbazone 1a and its 3-β-acetoxy and 3β-chloro derivatives 2a and 3a, respectively. The reactions of 1a, 2a and 3a with thionyl chloride in dichloromethane at low temperature afforded the cyclized thiadiazole 4 and its 3β-acetoxy- and 3β-chloro analogues 5 and 6 in good yields.

  17. Synthesis of oligonucleotide phosphorodithioates

    DEFF Research Database (Denmark)

    Beaton, G.; Brill, W. K D; Grandas, A.;

    1991-01-01

    The synthesis of DNA containing sulfur at the two nonbonding internucleotide valencies is reported. Several different routes using either tervalent or pentavalent mononucleotide synthons are described. © 1991....

  18. Synthesis, Reactivity and Biological Activity of Novel Bisbenzofuran-2-yl-Methanone Derivatives

    Directory of Open Access Journals (Sweden)

    Cavit Kazaz

    2005-11-01

    Full Text Available Preparation of bisbenzofuran-2-yl-methanone (1, the corresponding ketoxime 4, semicarbazone and thiosemicarbazone 3a and 3b, ether derivatives of the ketoximes 5a-j and the alcohol 2 are described. These substances have been prepared in excellent yields. All the synthesized compounds except 5i have been tested against five different microorganisms and some of them were found to be active against some of the species studied.

  19. SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF SOME CHALCONE DERIVATIVES AND THEIR COPPERCOMPLEXES

    OpenAIRE

    P. M. Rachmale

    2012-01-01

    In the present investigation, 4-chloro acetophenone on condensation with 2-nitro benzaldehydes in methanolic NaOH solution yielded the corresponding chalcone. These chalcone were further reacted with Isonicotyl hydrazide and semicarbazide in ethanol which led to the formation of chalcone Isonicotyl hydrazone and chalcone semicarbazone derivatives respectively. The newly synthesized derivatives and there copper complexes were characterized on the basis of their chemical properties and spect...

  20. ONE POT SYNTHESIS OF THIAZOLIDINONES IN MOLTEN (ET3NHHSO4. ONE Eintopfsynthese Thiazolidinone in Mölten (Et3NH HSO4.

    Directory of Open Access Journals (Sweden)

    Maryam Kalantari

    2013-07-01

    Full Text Available Some thiazolidinones have been synthesized by the reaction of semicarbazones with acetylenic esters in molten (Et3NHHSO4 as an acid ionic liquid. This method provides several advantages such as operational simplicity, higher yield, safety and environment friendly protocol.

  1. Synthesis of Mechanisms

    DEFF Research Database (Denmark)

    Hansen, John Michael

    1999-01-01

    These notes describe an automated procedure for analysis and synthesis of mechanisms. The analysis method is based on the body coordinate formulation, and the synthesis is based on applying optimization methods, used to minimize the difference between an actual and a desired behaviour...

  2. Synthesis of Isoiminosugars

    DEFF Research Database (Denmark)

    Hyldtoft, Lene; Godskesen, Michael Anders; Lundt, Inge

    1998-01-01

    A short synthesis of isoiminosugars have been developed. Bromolactones are diastereoselectively alkylated at C-2 followed by ring closure to the corresponding lactams. Reduction of these then gives isoiminosugars......A short synthesis of isoiminosugars have been developed. Bromolactones are diastereoselectively alkylated at C-2 followed by ring closure to the corresponding lactams. Reduction of these then gives isoiminosugars...

  3. Formal synthesis of (+)-discodermolide.

    Science.gov (United States)

    Francavilla, Charles; Chen, Weichun; Kinder, Frederick R

    2003-04-17

    [structure: see text] Herein we report the formal total synthesis of (+)-discodermolide in 21 steps (longest linear sequence) from commercially available Roche ester. This synthesis features the assembly of C(9-18) and C(19-24) fragments via a metal-chelated aldol coupling reaction.

  4. Synthesis of zeolite membranes

    Institute of Scientific and Technical Information of China (English)

    JIANG Haiyang; ZHANG Baoquan; Y. S. Lin; LI Yongdan

    2004-01-01

    Zeolite membranes offer great application potentials in membrane separation and/or reaction due to their excellent separation performance and catalytic ability. Up to present, various synthesis methods of zeolite membranes have been developed, including embedded method,in-situ hydrothermal synthesis method, and secondary growth method etc. Compared with the in-situ hydrothermal synthesis method, the secondary growth method possesses a variety of advantages such as easier operation, higher controllability in crystal orientation, microstructure and film thickness, leading to much better reproducibility. This review provides a concise summary and analysis of various synthesis methods reported in the literature. In particular, the secondary growth method was discussed in detail in terms of crystal orientation, defects and crystal grain layers. Some critical issues were also highlighted, which were conducive to the improvement in the synthesis technology of zeolite membranes.

  5. VHDL for logic synthesis

    CERN Document Server

    Rushton, Andrew

    2011-01-01

    Many engineers encountering VHDL (very high speed integrated circuits hardware description language) for the first time can feel overwhelmed by it. This book bridges the gap between the VHDL language and the hardware that results from logic synthesis with clear organisation, progressing from the basics of combinational logic, types, and operators; through special structures such as tristate buses, register banks and memories, to advanced themes such as developing your own packages, writing test benches and using the full range of synthesis types. This third edition has been substantially rewritten to include the new VHDL-2008 features that enable synthesis of fixed-point and floating-point hardware. Extensively updated throughout to reflect modern logic synthesis usage, it also contains a complete case study to demonstrate the updated features. Features to this edition include: * a common VHDL subset which will work across a range of different synthesis systems, targeting a very wide range of technologies...

  6. Gas Phase Nanoparticle Synthesis

    Science.gov (United States)

    Granqvist, Claes; Kish, Laszlo; Marlow, William

    This book deals with gas-phase nanoparticle synthesis and is intended for researchers and research students in nanomaterials science and engineering, condensed matter physics and chemistry, and aerosol science. Gas-phase nanoparticle synthesis is instrumental to nanotechnology - a field in current focus that raises hopes for environmentally benign, resource-lean manufacturing. Nanoparticles can be produced by many physical, chemical, and even biological routes. Gas-phase synthesis is particularly interesting since one can achieve accurate manufacturing control and hence industrial viability.

  7. Hydrothermal organic synthesis experiments

    Science.gov (United States)

    Shock, Everett L.

    1992-01-01

    Ways in which heat is useful in organic synthesis experiments are described, and experiments on the hydrothermal destruction and synthesis of organic compounds are discussed. It is pointed out that, if heat can overcome kinetic barriers to the formation of metastable states from reduced or oxidized starting materials, abiotic synthesis under hydrothermal conditions is a distinct possibility. However, carefully controlled experiments which replicate the descriptive variables of natural hydrothermal systems have not yet been conducted with the aim of testing the hypothesis of hydrothermal organic systems.

  8. Asymmetric synthesis v.4

    CERN Document Server

    Morrison, James

    1984-01-01

    Asymmetric Synthesis, Volume 4: The Chiral Carbon Pool and Chiral Sulfur, Nitrogen, Phosphorus, and Silicon Centers describes the practical methods of obtaining chiral fragments. Divided into five chapters, this book specifically examines initial chiral transmission and extension. The opening chapter describes the so-called chiral carbon pool, the readily available chiral carbon fragments used as building blocks in synthesis. This chapter also provides a list of 375 chiral building blocks, along with their commercial sources, approximate prices, and methods of synthesis. Schemes involving

  9. 2002 Annual report: synthesis

    International Nuclear Information System (INIS)

    This synthesis of the Annual Report 2002 presents information of the main activities on the scope of the radiation protection and nuclear safety of the Nuclear Regulatory Authority (ARN) of the Argentina during 2002

  10. 2000 Annual report: synthesis

    International Nuclear Information System (INIS)

    This synthesis of the Annual Report 2000 present information of the main activities on the scope of the radiation protection and nuclear safety of the Nuclear Regulatory Authority (NRA) of the Argentina during 2000

  11. 2001 Annual report: synthesis

    International Nuclear Information System (INIS)

    This synthesis of the Annual Report 2001 presents information of the main activities on the scope of the radiation protection and nuclear safety of the Nuclear Regulatory Authority (ARN) of the Argentina during 2001

  12. Total synthesis of atropurpuran.

    Science.gov (United States)

    Gong, Jing; Chen, Huan; Liu, Xiao-Yu; Wang, Zhi-Xiu; Nie, Wei; Qin, Yong

    2016-01-01

    Due to their architectural intricacy and biological significance, the synthesis of polycyclic diterpenes and their biogenetically related alkaloids have been the subject of considerable interest over the last few decades, with progress including the impressive synthesis of several elusive targets. Despite tremendous efforts, conquering the unique structural types of this large natural product family remains a long-term challenge. The arcutane diterpenes and related alkaloids, bearing a congested tetracyclo[5.3.3.0(4,9).0(4,12)]tridecane unit, are included in these unsolved enigmas. Here we report a concise approach to the construction of the core structure of these molecules and the first total synthesis of (±)-atropurpuran. Pivotal features of the synthesis include an oxidative dearomatization/intramolecular Diels-Alder cycloaddition cascade, sequential aldol and ketyl-olefin cyclizations to assemble the highly caged framework, and a chemoselective and stereoselective reduction to install the requisite allylic hydroxyl group in the target molecule. PMID:27387707

  13. Synthesis of Acetylhomoagmatine

    Directory of Open Access Journals (Sweden)

    Carmenza Duque

    2006-08-01

    Full Text Available Abstract: The first total synthesis of acetylhomoagmatine, a natural product isolated form the methanolic extracts from the sponge Cliona celata, is performed in four steps in a very high yield.

  14. Ethics of Chemical Synthesis

    OpenAIRE

    Joachim Schummer

    2001-01-01

    Unlike other branches of science, the scientific products of synthetic chemistry are not only ideas but also new substances that change our material world, for the benefit or harm of living beings. This paper provides for the first time a systematical analysis of moral issues arising from chemical synthesis, based on concepts of responsibility and general morality. Topics include the questioning of moral neutrality of chemical synthesis as an end in itself, chemical weapons research, moral ob...

  15. Instrument Modeling and Synthesis

    Science.gov (United States)

    Horner, Andrew B.; Beauchamp, James W.

    During the 1970s and 1980s, before synthesizers based on direct sampling of musical sounds became popular, replicating musical instruments using frequency modulation (FM) or wavetable synthesis was one of the “holy grails” of music synthesis. Synthesizers such as the Yamaha DX7 allowed users great flexibility in mixing and matching sounds, but were notoriously difficult to coerce into producing sounds like those of a given instrument. Instrument design wizards practiced the mysteries of FM instrument design.

  16. Synthesis, crystal structure, spectroscopic characterization and theoretical study of (2E)-N-phenyl-2-(pyridin-3-ylmethylidene)hydrazinecarboxamide

    Science.gov (United States)

    Soria-Martínez, R.; Mendoza-Meroño, R.; García-Granda, S.

    2016-02-01

    In this work, the experimental and theoretical study of new semicarbazone have been reported. The new semicarbazone was synthesized and characterized by FT-IR, FT-Raman and NMR, and the crystal structure was determined by X-ray single-crystal diffraction. The crystallographic asymmetric unit was optimized using DFT method and compared with the experimental data. The experimental FT-IR and FT-Raman have been compared with calculated vibrational frequencies, using B3LYP/6-311*G(d,p). The stability and charge delocalization were studied by natural bond orbital (NBO) analysis as well as the molecular electrostatic potential (MEP). The 1H and 13C chemical shifts values have been calculated by the GIAO method. Non covalent interactions analysis in real space was done, based on the electron density and its derivates, it provides a rich representation of VdW interactions, hydrogen bonds, and the inter and intramolecular steric repulsions.

  17. Synthesis of monoketo and monohydroxy eicosanoic acids and esters with substituents at odd–numbered (3-13 carbons

    Directory of Open Access Journals (Sweden)

    HULYA CELIK

    2002-07-01

    Full Text Available In this study, monoketo and monohydroxy eicosanoic acids and their methyl esters with the position of the substituent on odd numbered carbon atoms from 3 to 13 were synthesized with high purity. Furthermore, the semicarbazone and anilide derivatives of the obtained keto acids were prepared. They were characterized by TLC, IR and 1H-NMR spectroscopy and their physical and chemical properties were established.

  18. Synthesis of a Fluorescence Reagent Bis(benzotriazo-1-le)-ethyldione Semicarbazone and Its Application in Determination of Proteins%荧光试剂二(苯并三唑-1-基)乙二酮缩氨基脲的合成及其在蛋白质测定中的应用

    Institute of Scientific and Technical Information of China (English)

    高峰; 朱英贵; 章丽; 谢筱娟; 王伦

    2004-01-01

    由苯并三唑、乙二醛、氨基脲合成了新荧光试剂二(苯并三唑-1-基)乙二酮缩氨基脲希夫碱. 通过1H NMR、红外光谱、元素分析确证了试剂的结构. 在pH=4.0的KH2PO4-H3PO4缓冲溶液中,该试剂在342 nm处(λex=284 nm)发射荧光,其强度随蛋白质的加入明显增强,据此建立了测定痕量蛋白质的新方法. 在最佳实验条件下,测定牛血清白蛋白、人血清白蛋白的线性范围分别为0~8.0×10-6 g/mL和1.0×10-5~0.25 g/mL ,检测限分别为5.3×10-9 g/mL、1.4×10-9 g/mL,用于合成样品的测定,结果令人满意.

  19. Synthesis of Poly[styrene(iodoso diacetate)] and Application in Regeneration of Carbonyl Compounds from Semicarbazones%聚苯乙烯二醋酸碘苯的合成及其在缩氨脲去保护基形成羰基化合物反应中的应用

    Institute of Scientific and Technical Information of China (English)

    张继振; 朱; 黄宪

    2001-01-01

    @@ 缩氨脲不仅可用于羰基化合物的分离和纯化[1], 而且在有机合成中也常用于保护羰基[2~5]. 因此, 研究缩氨脲去保护基再生成相应的羰基化合物的方法仍然是有机合成方法中重要的研究课题. 文献报道使缩氨脲去保护基的常用试剂有邻苯二酐[1]、浓盐酸[6]、阳离子交换树脂[6,7]、氯化亚钛[8]、溴酸钾[9]和氯化铜(Ⅱ)二水合物[10]等.

  20. The Direct Electrochemical Synthesis of Cu( Ⅱ), Zn(Ⅱ), Fe(Ⅱ) Complexes of p-dimethylaminobenzaldehyde Semicarbazone%对二甲氨基苯甲醛缩氨基脲Cu(Ⅱ)、Zn(Ⅱ)、Fe(Ⅱ)配合物的直接电化学合成

    Institute of Scientific and Technical Information of China (English)

    李虹; 刘建宁; 赵建设

    2000-01-01

    用电化学金属阳极氧化法在非水溶剂中合成了对二甲氨基苯甲醛缩氨基脲(HL)与Cu(Ⅱ) 、Zn(Ⅱ)、Fe(Ⅱ)的配合物,通过元素分析、红外光谱、紫外光谱、摩尔电导等对配合物进行了表征.

  1. Synthesis and crystal structure of a lead (Ⅱ)complex of the Schiff base derived from pyridine- 2 -carbaldehyde and semicarbazone%Schiff碱吡啶-2-甲醛缩氨基脲铅(Ⅱ)配合物的合成和晶体结构

    Institute of Scientific and Technical Information of China (English)

    李冬青; 周健; 刘星; 袁余洲; 罗志辉; 张勇

    2006-01-01

    缩氨基脲(或含硫)希夫碱及其配合物具有抗病毒、抗菌、抗麻风病等生物活性,因而引起了人们极度大的关注。为了拓宽缩氨基脲及其配合物的研究领域,进一步了解该类化合物的结构特征,本文报道了Schiff碱吡啶-2-甲醛缩氨基脲铅(Ⅱ)配合物的合成和晶体结构。

  2. Scchiff碱N-氧化吡啶-2-甲醛缩氨基脲及其铜配合物的合成、晶体结构及谱学性质的研究%Synthesis,Crystal Structure and Spectroscopic Properties of a Copper(Ⅱ)Complex of the Schiff Base Derived from Picolinaldehyde N-oxide and Semicarbazone

    Institute of Scientific and Technical Information of China (English)

    梁宏; 陈雄斌; 胡瑞祥; 陈振锋; 郁开北

    2002-01-01

    合成了Schiff碱N-氧化吡啶-2-甲醛缩氨基脲(PNOS)及其配合物[Cu(PNOS)(NO3)2],并用单晶X射线衍射法测定了配体和配合物结构.PNOS晶体中通过传统氢键形成双层二维网状结构,再由非传统氢键自组装成三维网状结构.配合物[Cu(PNOS)(NO3)2]中的铜为六配位,畸变八面体结构,Schiff碱(PNOS)通过N-氧化吡啶N-O的O原子,亚胺基C=N的N原子,及羰基C=O的O原子与铜配位;一个硝基以单齿配体形式与铜配位,另一个则以双齿配体形式配位.配合物分子通过经典氢键相互作用,形成单层二维网状结构,再通过非经典氢键作用,自组装成双层二维网状结构.

  3. 3-Nitro­benzaldehyde thio­semicarbazone

    OpenAIRE

    Wu, De-Hong; Li, Zhu-Feng; Zhang, You-Hong

    2008-01-01

    The mol­ecule of the title compound, C8H8N4O2S, adopts an E configuration about both the C—N bonds. In the crystal structure, adjacent mol­ecules are linked by inter­molecular N—H⋯S hydrogen-bonding inter­actions, forming chains running parallel to the b axis.

  4. (E-1-(4-Bromophenylethan-1-one semicarbazone

    Directory of Open Access Journals (Sweden)

    Hoong-Kun Fun

    2009-07-01

    Full Text Available In the title compound, C9H10BrN3O, the hydrazone portion and aliphatic chain are essentially coplanar [maximum deviation 0.057 (15 Å] and the mean plane makes a dihedral angle of 70.9 (6° with the benzene ring. The main feature of the crystal structure is the intermolecular N—H...O hydrogen bond, which links molecules into zigzag chains along the a axis. These chains are further stacked along the b axis. The crystal structure features non-classical intermolecular C—H...O interactions. The crystal studied was a nonmerohedral twin, with a twin ratio of 0.505 (1:0.495 (1.

  5. ANTIINFLAMMATORY ACTIVITY OF SOME NOVEL METHYLPHENYL SEMICARBAZONE DERIVATIVES

    Directory of Open Access Journals (Sweden)

    Singh Hemendra Pratap

    2011-06-01

    Full Text Available In the present study a series of methylphenylsemicarbazones was synthesized and evaluated for their anti-inflammatory activities by cotton pellet induced granuloma, formalin induced paw edema and carrageenan induced paw edema in rats. Most of the compounds were found to be more or comparable potent than the reference standard drug in all the three animal models. Based on the results of anti-inflammatory study it was found that chloro substitution in the aldehydic moiety and amino substitution in acetophenic moiety of chalcone (compound 28 exhibited better activity. Lengthening of carbon chain also favor anti-inflammatory activity.

  6. (Z-1-(2,5-Dichloro-3-thienylethanone semicarbazone

    Directory of Open Access Journals (Sweden)

    Hoong-Kun Fun

    2009-08-01

    Full Text Available The title molecule, C7H7Cl2N3OS, is approximately planar [maximum deviation = 0.062 (1 Å]. Short intermolecular distances between the centroids of the five-membered rings [3.5340 (8 Å] indicate the existence of π–π interactions. An interesting feature of the crystal structure is the presence of short intramolecular Cl...N interactions [3.0015 (11 Å]. Molecules are linked via pairs of intermolecular N—H...O hydrogen bonds, generating R22(8 ring motifs. Furthermore, N—H...O hydrogen bonds form R21(7 ring motifs with C—H...O contacts, further consolidating the crystal structure. In the crystal, molecules are linked by these intermolecular interactions, forming chains along [001].

  7. Direct Dimethyl Ether Synthesis

    Institute of Scientific and Technical Information of China (English)

    Takashi Ogawa; Norio Inoue; Tutomu Shikada; Yotaro Ohno

    2003-01-01

    Dimethyl ether (DME) is a clean and economical alternative fuel which can be produced from natural gas through synthesis gas. The properties of DME are very similar to those of LP gas. DME can be used for various fields as a fuel such as power generation, transportation, home heating and cooking,etc. It contains no sulfur or nitrogen. It is not corrosive to any metal and not harmful to human body. An innovative process of direct synthesis of DME from synthesis gas has been developed. Newly developed catalyst in a slurry phase reactor gave a high conversion and high selectivity of DME production. One and half year pilot scale plant (5 tons per day) testing, which was supported by METI, had successfully finished with about 400 tons DME production.

  8. Synthesis of organosilicon compounds

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, G.

    1996-12-31

    Silicon-containing polymers have been a focus of synthesis and study in Dr. Barton`s group because of their chemistry and properties which are not offered by other systems or materials. For example, the polymer -[-SiMe{sub 2}C{triple_bond}C-]{sub n}-can be easily processed to films or fibers from melt or solution, and thermally converted to a SiC-containing ceramic in high yield at high temperature. In recent years, carbosilane dendritic polymers have been of great interests in many research groups. However, no synthesis of carbosilane dendrimers with functionalties both inside and outside the dendrimer has been reported. Functionality is very important in the synthesis of preceramic polymers. This thesis will be devoted to exploring several new organosilicon polymer systems.

  9. Supercritical Synthesis of Biodiesel

    Directory of Open Access Journals (Sweden)

    Michel Vaultier

    2012-07-01

    Full Text Available The synthesis of biodiesel fuel from lipids (vegetable oils and animal fats has gained in importance as a possible source of renewable non-fossil energy in an attempt to reduce our dependence on petroleum-based fuels. The catalytic processes commonly used for the production of biodiesel fuel present a series of limitations and drawbacks, among them the high energy consumption required for complex purification operations and undesirable side reactions. Supercritical fluid (SCF technologies offer an interesting alternative to conventional processes for preparing biodiesel. This review highlights the advances, advantages, drawbacks and new tendencies involved in the use of supercritical fluids (SCFs for biodiesel synthesis.

  10. Stereoselective Synthesis of (+)-Boronolide

    Institute of Scientific and Technical Information of China (English)

    HU,Shou-Gang; HU,Tai-Shan; WU,Yu-Lin

    2004-01-01

    @@ (+)-Boronolide (1) and its deacetylated products have attracted much attention of synthetic chemists due to their diverse biological properties as well as their structural complexities.[1] Many of these reported synthesis involved dehydrogenation of δ-lactone by using benzeneseleninic anhydride or ring-closing olefin metathesis (RCM) to introduce the requisite α,β-unsaturated δ-lactone in boronolide. Here, we report the synthesis of boronolide with diastereoselective propargylation of α-hydroxy aldehyde as the key step and D-gluconolactone as the starting material.

  11. Diophantine frequency synthesis.

    Science.gov (United States)

    Sotiriadis, Paul Peter

    2006-11-01

    A methodology for fine-step, fast-hopping, low-spurs phase-locked loop based frequency synthesis is presented. It uses mathematical properties of integer numbers and linear Diophantine equations to overcome the constraining relation between frequency step and phase-comparator frequency that is inherent in conventional phase-locked loop based frequency synthesis. The methodology leads to fine-step, fast-hopping, modular-structured frequency synthesizers with potentially very low spurs, especially in the vicinity of the carrier. The paper focuses on the mathematical principles of the new methodology and the related number theoretic algorithms. PMID:17091835

  12. Optimization of synthesis of 2-amino-5-aryl-1,3,4-oxadiazole%2-氨基-5-芳基-1,3,4-噁二唑的合成及工艺优化

    Institute of Scientific and Technical Information of China (English)

    刘玉婷; 黄涛; 刘蓓蓓; 尹大伟; 杨晓刚

    2015-01-01

    A series of 2‐amino‐5‐aryl‐1 ,3 ,4‐oxadiazole analogues were synthesized via substi‐tuted benzaldehyde and semicarbazide hydrochloride in this paper .T he influence of process conditions to productivity was discussed .The results indicated that the best synthesis condi‐tions of semicarbazide was that the mole ratio of n(substituted benzaldehyde)∶ n(semicarba‐zide hydrochloride) was 1 .0∶1 .1 ,the reaction temperature was 80 ℃ ,the reaction time was 2 h;the best synthesis conditions of 2‐amino‐5‐aryl‐1 ,3 ,4‐oxadiazole was that the mole ratio of n(semicarbazone)∶ n(anhydrous sodium acetate)∶ n(bromine) was 1 .0∶4 .0∶1 .2 ,the reaction time was 5 h ,the reaction temperature was 15 ℃ .The yield was above 85% .All the structures of the products were characterized by IR and elemental analysis .%以取代苯甲醛与氨基脲为原料,合成了一系列2‐氨基‐5‐芳基‐1,3,4‐噁二唑.讨论了反应条件对产率的影响,得到了最佳工艺条件.实验结果表明,合成半缩脲的最佳条件为:n(苯甲醛)∶ n(盐酸氨基脲)=1.0∶1.1,反应温度为80℃,反应时间为2h;合成2‐氨基‐5‐芳基‐1,3,4‐噁二唑的最佳条件为:n(半缩脲)∶ n(无水醋酸钠)∶ n(溴)=1.0∶4.0∶1.2,反应温度为15℃,反应时间为5 h .所有化合物的产率均在85%以上,且其结构均经IR、元素分析等进行了表征.

  13. An Approach to Interface Synthesis

    DEFF Research Database (Denmark)

    Madsen, Jan; Hald, Bjarne

    1995-01-01

    may contain the re-use of existing modules). The interface synthesis approach describes the basic transformations needed to transform the server interface description into an interface description on the client side of the communication medium. The synthesis approach is illustrated through a point......Presents a novel interface synthesis approach based on a one-sided interface description. Whereas most other approaches consider interface synthesis as optimizing a channel to existing client/server modules, we consider the interface synthesis as part of the client/server module synthesis (which......-to-point communication, but is applicable to synthesis of a multiple client/server environment. The interface description is based on a formalization of communication events....

  14. Synthesis of acrylic prepolymer

    International Nuclear Information System (INIS)

    An acrylic prepolymer was synthesized from glycidyl methacrylate (GMA), butyl methacrylate (BMA), methyl methacrylate (MMA) and acrylic acid (AA). Butyl acetate (BAc), benzoyl peroxide (BzO), 4-methoxyphenol (MPh) and triethylamine (TEA) were used as solvent, initiator, inhibitor and catalyst respectively. Observations of the synthesis leading to the formation of acrylic prepolymer are described. (author)

  15. Synthesis beyond the molecule

    NARCIS (Netherlands)

    Reinhoudt, D.N.; Crego-Calama, M.

    2002-01-01

    Weak, noncovalent interactions between molecules control many biological functions. In chemistry, noncovalent interactions are now exploited for the synthesis in solution of large supramolecular aggregates. The aim of these syntheses is not only the creation of a particular structure, but also the i

  16. Enzymatic synthesis of vanillin

    NARCIS (Netherlands)

    van den Heuvel, RHH; Fraaije, MW; Laane, C; van Berkel, WJH; Heuvel, Robert H.H. van den; Berkel, Willem J.H. van

    2001-01-01

    Due to increasing interest in natural vanillin, two enzymatic routes for the synthesis of vanillin were developed. The flavoprotein vanillyl alcohol oxidase (VAO) acts on a wide range of phenolic compounds and converts both creosol and vanillylamine to vanillin with high yield. The VAO-mediated conv

  17. The Synthesis of Glycoglycerolipids

    Institute of Scientific and Technical Information of China (English)

    Chun Xia LI; Ying Xia LI; Ling Bo YU; Hua ZHANG; Shi Dong CHU; Hua Shi GUAN

    2003-01-01

    A convenient synthetic route was developed for the synthesis of the novel glycolipids: 1, 2-di-O-acyl-3-O-(2'-acylamide-2'-deoxy-α-D-glucopyranosyl)-sn-glycerols. 10 new compounds of glycolipids with different acyl groups were obtained.

  18. Distributed Priority Synthesis

    Directory of Open Access Journals (Sweden)

    Harald Ruess

    2012-11-01

    Full Text Available Given a set of interacting components with non-deterministic variable update and given safety requirements, the goal of priority synthesis is to restrict, by means of priorities, the set of possible interactions in such a way as to guarantee the given safety conditions for all possible runs. In distributed priority synthesis we are interested in obtaining local sets of priorities, which are deployed in terms of local component controllers sharing intended next moves between components in local neighborhoods only. These possible communication paths between local controllers are specified by means of a communication architecture. We formally define the problem of distributed priority synthesis in terms of a multi-player safety game between players for (angelically selecting the next transition of the components and an environment for (demonically updating uncontrollable variables. We analyze the complexity of the problem, and propose several optimizations including a solution-space exploration based on a diagnosis method using a nested extension of the usual attractor computation in games together with a reduction to corresponding SAT problems. When diagnosis fails, the method proposes potential candidates to guide the exploration. These optimized algorithms for solving distributed priority synthesis problems have been integrated into the VissBIP framework. An experimental validation of this implementation is performed using a range of case studies including scheduling in multicore processors and modular robotics.

  19. Total Synthesis of Naloxone

    Institute of Scientific and Technical Information of China (English)

    HU Wen-Xiang; WANG Jian-Ying; XU Ming

    2003-01-01

    @@ Naloxone (1) is one of the 14-hydroxyl substituted opium antagonists which are valuable medications for treat ment of opiate abuse, opiate overdose, and alcohol addiction. Here, the total synthesis of naloxone was described. We selected 2,6-dihydroxynaphalene (2) as the starting material.

  20. Sizing up surfactant synthesis.

    Science.gov (United States)

    Han, SeungHye; Mallampalli, Rama K

    2014-08-01

    Phosphatidylcholine is generated through de novo synthesis and remodeling involving a lysophospholipid. In this issue of Cell Metabolism, research from the Shimizu lab (Harayama et al., 2014) demonstrates the highly selective enzymatic behavior of lysophospholipid acyltransferases. The authors present an enzymatic model for phosphatidylcholine molecular species diversification that impacts surfactant formation.

  1. Industrial scale gene synthesis.

    Science.gov (United States)

    Notka, Frank; Liss, Michael; Wagner, Ralf

    2011-01-01

    The most recent developments in the area of deep DNA sequencing and downstream quantitative and functional analysis are rapidly adding a new dimension to understanding biochemical pathways and metabolic interdependencies. These increasing insights pave the way to designing new strategies that address public needs, including environmental applications and therapeutic inventions, or novel cell factories for sustainable and reconcilable energy or chemicals sources. Adding yet another level is building upon nonnaturally occurring networks and pathways. Recent developments in synthetic biology have created economic and reliable options for designing and synthesizing genes, operons, and eventually complete genomes. Meanwhile, high-throughput design and synthesis of extremely comprehensive DNA sequences have evolved into an enabling technology already indispensable in various life science sectors today. Here, we describe the industrial perspective of modern gene synthesis and its relationship with synthetic biology. Gene synthesis contributed significantly to the emergence of synthetic biology by not only providing the genetic material in high quality and quantity but also enabling its assembly, according to engineering design principles, in a standardized format. Synthetic biology on the other hand, added the need for assembling complex circuits and large complexes, thus fostering the development of appropriate methods and expanding the scope of applications. Synthetic biology has also stimulated interdisciplinary collaboration as well as integration of the broader public by addressing socioeconomic, philosophical, ethical, political, and legal opportunities and concerns. The demand-driven technological achievements of gene synthesis and the implemented processes are exemplified by an industrial setting of large-scale gene synthesis, describing production from order to delivery.

  2. SYNTHESIS AND ANTIMICROBIAL ACTIVITY OF SOME CHALCONE DERIVATIVES AND THEIR COPPERCOMPLEXES

    Directory of Open Access Journals (Sweden)

    P. M. Rachmale

    2012-03-01

    Full Text Available In the present investigation, 4-chloro acetophenone on condensation with 2-nitro benzaldehydes in methanolic NaOH solution yielded the corresponding chalcone. These chalcone were further reacted with Isonicotyl hydrazide and semicarbazide in ethanol which led to the formation of chalcone Isonicotyl hydrazone and chalcone semicarbazone derivatives respectively. The newly synthesized derivatives and there copper complexes were characterized on the basis of their chemical properties and spectroscopic data such as IR, NMR and UV. All newly synthesized compounds were evaluated for their antibacterial activities against E. coli and S. aureus also for antifungal activities against P. notatum.

  3. Synthesis through Trans-disciplinarity

    DEFF Research Database (Denmark)

    Hansen, Hanne Tine Ring

    2006-01-01

    experience. In relation to ‘environmentally sustainable' architecture the importance of synthesis becomes even more apparent, however, as the success of the design depends on how, and if, a synthesis is achieved between technology and architectural design.[2] This understanding has led me to consider how...... synthesis is a requirement for creating successful ‘environmentally sustainable' architecture through the application of trans-disciplinarity, which leads to an increased awareness of the differences in decision-making as well as that of communication barriers between the different professions....... These parameters play a fundamental role in relation to the achievement of synthesis in a world where professions merge and new hybrid professions and educations emerge. [1]: dictionary.reference.com 2006: http://dictionary.reference.com/search?q=synthesis (accessed April 1st 2006) [2]: If synthesis...

  4. Ethics of Chemical Synthesis

    Directory of Open Access Journals (Sweden)

    Joachim Schummer

    2001-10-01

    Full Text Available Unlike other branches of science, the scientific products of synthetic chemistry are not only ideas but also new substances that change our material world, for the benefit or harm of living beings. This paper provides for the first time a systematical analysis of moral issues arising from chemical synthesis, based on concepts of responsibility and general morality. Topics include the questioning of moral neutrality of chemical synthesis as an end in itself, chemical weapons research, moral objections against improving material conditions of life by chemical means, and freedom of research. The paper aims at providing both a sound basis for moral judgements of chemistry in a public discourse and a framework for chemists to reflect on the moral relevance of their activity.

  5. Expanding the modern synthesis.

    Science.gov (United States)

    Wallace, Rodrick

    2010-10-01

    The Modern Evolutionary Synthesis formalizes the role of variation, heredity, differential reproduction and mutation in population genetics. Here we explore a mathematical structure, based on the asymptotic limit theorems of communication theory, that instantiates the punctuated dynamic relations of organisms with their embedding environments, including the possibility of the transfer of heritage information between different classes of organism. The approach applies a standard coevolutionary argument to genes, environment, and gene expression reconfigured as interacting information sources. In essence, we provide something of a formal roadmap for the modernization of the Modern Synthesis, making applications to both relatively rapid evolutionary punctuated equilibrium and to the conservation of ecological interactions across deep evolutionary time. PMID:20965439

  6. Prebiotic synthesis of histidine

    Science.gov (United States)

    Shen, C.; Yang, L.; Miller, S. L.; Oro, J.

    1990-01-01

    The prebiotic formation of histidine (His) has been accomplished experimentally by the reaction of erythrose with formamidine followed by a Strecker synthesis. In the first step of this reaction sequence, the formation of imidazole-4-acetaldehyde took place by the condensation of erythrose and formamidine, two compounds that are known to be formed under prebiotic conditions. In a second step, the imidazole-4-acetaldehyde was converted to His, without isolation of the reaction products by adding HCN and ammonia to the reaction mixture. LC, HPLC, thermospray liquid chromatography-mass spectrometry, and tandem mass spectrometry were used to identify the product, which was obtained in a yield of 3.5% based on the ratio of His/erythrose. This is a new chemical synthesis of one of the basic amino acids which had not been synthesized prebiotically until now.

  7. Total Synthesis of Millingtonine.

    Science.gov (United States)

    Brown, Patrick D; Lawrence, Andrew L

    2016-07-11

    Millingtonine is a glycosidic alkaloid that exists as a pair of pseudo-enantiomeric diastereomers. Consideration of the likely biosynthetic origins of this unusual natural product has resulted in the development of a seven-step total synthesis. Results from this synthetic work provide evidence in support of a proposed network of biosynthetic pathways that can account for the formation of several phenylethanoid natural products. PMID:27249628

  8. Enzymatic synthesis of vanillin

    OpenAIRE

    van den Heuvel, RHH; Fraaije, MW; Laane, C; van Berkel, WJH; Heuvel, Robert H.H. van den; van Berkel, Willem J. H.

    2001-01-01

    Due to increasing interest in natural vanillin, two enzymatic routes for the synthesis of vanillin were developed. The flavoprotein vanillyl alcohol oxidase (VAO) acts on a wide range of phenolic compounds and converts both creosol and vanillylamine to vanillin with high yield. The VAO-mediated conversion of creosol proceeds via a two-step process in which the initially formed vanillyl alcohol is further oxidized to vanillin. Catalysis is limited by the formation of an abortive complex betwee...

  9. Towards a new Synthesis

    OpenAIRE

    Foss, Nicolai J.; Klein, Peter G.; Kor, Yasemin Y.; Joseph T. Mahoney

    2006-01-01

    This paper maintains that the consistent application of subjectivism helps to reconcile contemporary entrepreneurship theory with strategic management research in general, and the resource−based view in particular. The paper synthesizes theoretical insights from Austrian economics and Penrose’s (1959) resources approach, arguing that entrepreneurship is inherently subjective and firm specific. This new synthesis describes how entrepreneurship is manifested in teams, and is driven by both hete...

  10. Total synthesis of teixobactin

    Science.gov (United States)

    Jin, Kang; Sam, Iek Hou; Po, Kathy Hiu Laam; Lin, Du'an; Ghazvini Zadeh, Ebrahim H.; Chen, Sheng; Yuan, Yu; Li, Xuechen

    2016-08-01

    To cope with the global bacterial multidrug resistance, scientific communities have devoted significant efforts to develop novel antibiotics, particularly those with new modes of actions. Teixobactin, recently isolated from uncultured bacteria, is considered as a promising first-in-class drug candidate for clinical development. Herein, we report its total synthesis by a highly convergent Ser ligation approach and this strategy allows us to prepare several analogues of the natural product.

  11. Stochastic component mode synthesis

    OpenAIRE

    Bah, Mamadou T.; Nair, Prasanth B.; Bhaskar, Atul; Keane, Andy J.

    2003-01-01

    In this paper, a stochastic component mode synthesis method is developed for the dynamic analysis of large-scale structures with parameter uncertainties. The main idea is to represent each component displacement using a subspace spanned by a set of stochastic basis vectors in the same fashion as in stochastic reduced basis methods [1, 2]. These vectors represent however stochastic modes in contrast to the deterministic modes used in conventional substructuring methods [3]. The Craig-Bampton r...

  12. Total synthesis of teixobactin.

    Science.gov (United States)

    Jin, Kang; Sam, Iek Hou; Po, Kathy Hiu Laam; Lin, Du'an; Ghazvini Zadeh, Ebrahim H; Chen, Sheng; Yuan, Yu; Li, Xuechen

    2016-01-01

    To cope with the global bacterial multidrug resistance, scientific communities have devoted significant efforts to develop novel antibiotics, particularly those with new modes of actions. Teixobactin, recently isolated from uncultured bacteria, is considered as a promising first-in-class drug candidate for clinical development. Herein, we report its total synthesis by a highly convergent Ser ligation approach and this strategy allows us to prepare several analogues of the natural product. PMID:27484680

  13. Microwave Multicomponent Synthesis

    Directory of Open Access Journals (Sweden)

    Helmut M. Hügel

    2009-12-01

    Full Text Available In the manner that very important research is often performed by multidisciplinary research teams, the applications of multicomponent reactions involving the combination of multiple starting materials with different functional groups leading to the higher efficiency and environmentally friendly construction of multifunctional/complex target molecules is growing in importance. This review will explore the advances and advantages in microwave multicomponent synthesis (MMS that have been achieved over the last five years.

  14. HNAB: synthesis and characterization

    Energy Technology Data Exchange (ETDEWEB)

    O' Keefe, D.M.

    1976-05-01

    The laboratory and pilot-plant scale synthesis of hexanitroazobenzene (HNAB) are detailed. Some of its physical, chemical, and explosive properties are presented and discussed. Among these are included polymorphic forms, thermal behavior, spectra, solubility, compatibility, toxicity, sensitivity to gap test, detonation velocity and pressure, impact sensitivity, and explosive classification. Finally, some alternate syntheses of HNAB and its intermediates are considered; some of these were successful and some were not.

  15. Microwave Multicomponent Synthesis

    OpenAIRE

    Helmut M Hügel

    2009-01-01

    In the manner that very important research is often performed by multidisciplinary research teams, the applications of multicomponent reactions involving the combination of multiple starting materials with different functional groups leading to the higher efficiency and environmentally friendly construction of multifunctional/complex target molecules is growing in importance. This review will explore the advances and advantages in microwave multicomponent synthesis (MMS) that have been achiev...

  16. Total synthesis of ochnaflavone

    OpenAIRE

    Monica M. Ndoile; van Heerden, Fanie R

    2013-01-01

    The first total syntheses of ochnaflavone, an asymmetric biflavone consisting of apigenin and luteolin moieties, and the permethyl ether of 2,3,2'',3''-tetrahydroochnaflavone have been achieved. The key steps in the synthesis of ochnaflavone were the formation of a diaryl ether and ring cyclization of an ether-linked dimeric chalcone to assemble the two flavone nuclei. Optimal experimental conditions for the oxidative cyclization to form ochnaflavone were established.

  17. Total synthesis of ochnaflavone

    Directory of Open Access Journals (Sweden)

    Monica M. Ndoile

    2013-07-01

    Full Text Available The first total syntheses of ochnaflavone, an asymmetric biflavone consisting of apigenin and luteolin moieties, and the permethyl ether of 2,3,2'',3''-tetrahydroochnaflavone have been achieved. The key steps in the synthesis of ochnaflavone were the formation of a diaryl ether and ring cyclization of an ether-linked dimeric chalcone to assemble the two flavone nuclei. Optimal experimental conditions for the oxidative cyclization to form ochnaflavone were established.

  18. PROTEIN SYNTHESIS GAME

    Directory of Open Access Journals (Sweden)

    J.C.Q. Carvalho

    2004-05-01

    Full Text Available The theoretical explanation of biological concepts, associated with the use of teaching games andmodels, intensify the comprehension and increase students interest, stimulating them to participateactively on the teaching-learning process. The sta of dissemination from Centro de BiotecnologiaMolecular Estrutural (CBME, in partnership with the Centro de Divulgac~ao Cientca e Cultural(CDCC, presents, in this work, a new educational resource denoted: Protein Synthesis Game. Theapproach of the game involves the cytological aspects of protein synthesis, directed to high schoolstudents. Students are presented to day-by-day facts related to the function of a given protein in thehuman body. Such task leads players to the goal of solving out a problem through synthesizing aspecied protein. The game comprises: (1 a board illustrated with the transversal section of animalcell, with its main structures and organelles and sequences of hypothetical genes; (2 cards with thedescription of steps and other structures required for protein synthesis in eukaryotic cells; (3 piecesrepresenting nucleotides, polynucleotides, ribosome, amino acids, and polypeptide chains. In order toplay the game, students take cards that sequentially permit them to acquire the necessary pieces forproduction of the protein described in each objective. Players must move the pieces on the board andsimulate the steps of protein synthesis. The dynamic of the game allows students to easily comprehendprocesses of transcription and translation. This game was presented to dierent groups of high schoolteachers and students. Their judgments have been heard and indicated points to be improved, whichhelped us with the game development. Furthermore, the opinions colleted were always favorable forthe application of this game as a teaching resource in classrooms.

  19. Phase contrast image synthesis

    DEFF Research Database (Denmark)

    Glückstad, J.

    1996-01-01

    A new method is presented for synthesizing arbitrary intensity patterns based on phase contrast imaging. The concept is grounded on an extension of the Zernike phase contrast method into the domain of full range [0; 2 pi] phase modulation. By controlling the average value of the input phase...... function and by choosing appropriate phase retardation at the phase contrast filter, a pure phase to intensity imaging is accomplished. The method presented is also directly applicable in dark field image synthesis....

  20. Gold Nanoparticle Microwave Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Krantz, Kelsie E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Christian, Jonathan H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Coopersmith, Kaitlin [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Washington, II, Aaron L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Murph, Simona H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-07-27

    At the nanometer scale, numerous compounds display different properties than those found in bulk material that can prove useful in areas such as medicinal chemistry. Gold nanoparticles, for example, display promise in newly developed hyperthermia therapies for cancer treatment. Currently, gold nanoparticle synthesis is performed via the hot injection technique which has large variability in final particle size and a longer reaction time. One underdeveloped area by which these particles could be produced is through microwave synthesis. To initiate heating, microwaves agitate polar molecules creating a vibration that gives off the heat energy needed. Previous studies have used microwaves for gold nanoparticle synthesis; however polar solvents were used that partially absorbed incident microwaves, leading to partial thermal heating of the sample rather than taking full advantage of the microwave to solely heat the gold nanoparticle precursors in a non-polar solution. Through this project, microwaves were utilized as the sole heat source, and non-polar solvents were used to explore the effects of microwave heating only as pertains to the precursor material. Our findings show that the use of non-polar solvents allows for more rapid heating as compared to polar solvents, a reduction in reaction time from 10 minutes to 1 minute, maximizes the efficiency of the reaction, and allows for reproducibility in the size/shape of the fabricated nanoparticles.

  1. Radiochemical synthesis of etomoxir

    International Nuclear Information System (INIS)

    Sodium 2-{6-(4-chlorophenoxy)hexyl}oxirane-2-carboxylate (Etomoxir) inhibits transport of fatty acids via the carnitine shuttle into mitochondria of muscle cells and prevents long chain fatty acids from providing energy through β-oxidation especially for muscle contraction. The objective of this synthesis is to develop a method for radioiodination of Etomoxir in order to explore its potential in diagnostic metabolic studies and molecular imaging. Thus, a method is described for the radiochemical synthesis and purification of ethyl 2-{6-(4-[131I]iodophenoxy)hexyl}oxirane-2-carboxylate (3) and 2-{6-(4-[131I]iodo-phenoxy)hexyl}oxirane-2-carboxylic acid (4). For the synthesis of these new agents, ethyl 2-{6-(4-bromophenoxy)hexyl}oxirane-2-carboxylate (1) and 2-{6-(4-bromophenoxy)hexyl}oxirane-2-carboxylic acid (2) were refluxed with [131I]NaI in the presence of anhydrous acetone at a temperature of 80 oC and 90 oC for a period of 3-4 hours, respectively. The method of radiolabeling, based on the nucleophilic exchange reaction, resulted in a radiochemical yield of 43% and 67% for compounds 3 and 4, respectively. This paper reports on the labeling of etomoxir with radioiodine as 124I labeled etomoxir may be of great importance in molecular imaging.

  2. Gold Nanoparticle Microwave Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Krantz, Kelsie E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Christian, Jonathan H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Coopersmith, Kaitlin [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Washington, II, Aaron L. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Murph, Simona H. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-07-27

    At the nanometer scale, numerous compounds display different properties than those found in bulk material that can prove useful in areas such as medicinal chemistry. Gold nanoparticles, for example, display promise in newly developed hyperthermia therapies for cancer treatment. Currently, gold nanoparticle synthesis is performed via the hot injection technique which has large variability in final particle size and a longer reaction time. One underdeveloped area by which these particles could be produced is through microwave synthesis. To initiate heating, microwaves agitate polar molecules creating a vibration that gives off the heat energy needed. Previous studies have used microwaves for gold nanoparticle synthesis; however, polar solvents were used that partially absorbed incident microwaves, leading to partial thermal heating of the sample rather than taking full advantage of the microwave to solely heat the gold nanoparticle precursors in a non-polar solution. Through this project, microwaves were utilized as the sole heat source, and non-polar solvents were used to explore the effects of microwave heating only as pertains to the precursor material. Our findings show that the use of non-polar solvents allows for more rapid heating as compared to polar solvents, and a reduction in reaction time from 10 minutes to 1 minute; this maximizes the efficiency of the reaction, and allows for reproducibility in the size/shape of the fabricated nanoparticles.

  3. Methods of component mode synthesis

    Science.gov (United States)

    Craig, R. R., Jr.

    1977-01-01

    A generalized substructure coupling, or component mode synthesis, procedure is described. Specific methods, applications, and such special topics as damping and experimental verification are surveyed.

  4. Synthesis of phenyl(1-/sup 14/C)acetylene and 1,4-diphenyl (1,4-/sup 14/C/sub 2/)butadiyne

    Energy Technology Data Exchange (ETDEWEB)

    Dhawan, S.N.; Kagan, J. (Illinois Univ., Chicago (USA). Dept. of Chemistry)

    1982-03-01

    Phenyl(1-/sup 14/C)acetylene (0.012mCi/mmole) was synthesized in 12.5% yield from (1-/sup 14/C)acetic acid through (1-/sup 14/C)acetophenone, its semicarbazone, and 4-phenyl-(4-/sup 14/C)1,2,3-selenadiazole obtained by selenium dioxide oxidation. Oxidative coupling gave 1,4-diphenyl(1,4-/sup 14/C/sub 2/)butadiyne in 80% yield.

  5. Hydrothermal organic synthesis experiments

    Science.gov (United States)

    Shock, Everett L.

    1992-01-01

    The serious scientific debate about spontaneous generation which raged for centuries reached a climax in the nineteenth century with the work of Spallanzani, Schwann, Tyndall, and Pasteur. These investigators demonstrated that spontaneous generation from dead organic matter does not occur. Although no aspects of these experiments addressed the issue of whether organic compounds could be synthesized abiotically, the impact of the experiments was great enough to cause many investigators to assume that life and its organic compounds were somehow fundamentally different than inorganic compounds. Meanwhile, other nineteenth-century investigators were showing that organic compounds could indeed be synthesized from inorganic compounds. In 1828 Friedrich Wohler synthesized urea in an attempt to form ammonium cyanate by heating a solution containing ammonia and cyanic acid. This experiment is generally recognized to be the first to bridge the artificial gap between organic and inorganic chemistry, but it also showed the usefulness of heat in organic synthesis. Not only does an increase in temperature enhance the rate of urea synthesis, but Walker and Hambly showed that equilibrium between urea and ammonium cyanate was attainable and reversible at 100 C. Wohler's synthesis of urea, and subsequent syntheses of organic compounds from inorganic compounds over the next several decades dealt serious blows to the 'vital force' concept which held that: (1) organic compounds owe their formation to the action of a special force in living organisms; and (2) forces which determine the behavior of inorganic compounds play no part in living systems. Nevertheless, such progress was overshadowed by Pasteur's refutation of spontaneous generation which nearly extinguished experimental investigations into the origins of life for several decades. Vitalism was dealt a deadly blow in the 1950's with Miller's famous spark-discharge experiments which were undertaken in the framework of the Oparin

  6. Lactobacillusassisted synthesis of titanium nanoparticles

    Directory of Open Access Journals (Sweden)

    Jha Anal

    2007-01-01

    Full Text Available AbstractAn eco-friendlylactobacillussp. (microbe assisted synthesis of titanium nanoparticles is reported. The synthesis is performed at room temperature. X-ray and transmission electron microscopy analyses are performed to ascertain the formation of Ti nanoparticles. Individual nanoparticles as well as a number of aggregates almost spherical in shape having a size of 40–60 nm are found.

  7. Memory-based logic synthesis

    CERN Document Server

    Sasao, Tsutomu

    2011-01-01

    This book describes the synthesis of logic functions using memories. It is useful to design field programmable gate arrays (FPGAs) that contain both small-scale memories, called look-up tables (LUTs), and medium-scale memories, called embedded memories. This is a valuable reference for both FPGA system designers and CAD tool developers, concerned with logic synthesis for FPGAs.

  8. Chemical synthesis on SU-8

    DEFF Research Database (Denmark)

    Qvortrup, Katrine; Taveras, Kennedy; Thastrup, Ole;

    2011-01-01

    In this paper we describe a highly effective surface modification of SU-8 microparticles, the attachment of appropriate linkers for solid-supported synthesis, and the successful chemical modification of these particles via controlled multi-step organic synthesis leading to molecules attached...

  9. Organic synthesis with stable isotopes

    International Nuclear Information System (INIS)

    Described is a scheme for the synthesis of L-arginine-1-13C utilizing methods developed for the synthesis of L-ornithine-1-13C from L-ornithine-2-13C and then converting ornithine into arginine with the enzyme acylase

  10. Radiochemical synthesis of etomoxir

    Energy Technology Data Exchange (ETDEWEB)

    Abbas, Hafiz G. [Institute of Nuclear Medicine and Oncology (INMOL), New Campus Road, Lahore (Pakistan); Yunus, M. [University of the Punjab, New Campus Road, Lahore (Pakistan); Feinendegen, Ludwig E., E-mail: feinendegen@gmx.ne [Department of Nuclear Medicine, Heinrich-Heine University Duesseldorf, Wannental 45, 88131 Lindau (Germany)

    2011-02-15

    Sodium 2-{l_brace}6-(4-chlorophenoxy)hexyl{r_brace}oxirane-2-carboxylate (Etomoxir) inhibits transport of fatty acids via the carnitine shuttle into mitochondria of muscle cells and prevents long chain fatty acids from providing energy through {beta}-oxidation especially for muscle contraction. The objective of this synthesis is to develop a method for radioiodination of Etomoxir in order to explore its potential in diagnostic metabolic studies and molecular imaging. Thus, a method is described for the radiochemical synthesis and purification of ethyl 2-{l_brace}6-(4-[{sup 131}I]iodophenoxy)hexyl{r_brace}oxirane-2-carboxylate (3) and 2-{l_brace}6-(4-[{sup 131}I]iodo-phenoxy)hexyl{r_brace}oxirane-2-carboxylic acid (4). For the synthesis of these new agents, ethyl 2-{l_brace}6-(4-bromophenoxy)hexyl{r_brace}oxirane-2-carboxylate (1) and 2-{l_brace}6-(4-bromophenoxy)hexyl{r_brace}oxirane-2-carboxylic acid (2) were refluxed with [{sup 131}I]NaI in the presence of anhydrous acetone at a temperature of 80 {sup o}C and 90 {sup o}C for a period of 3-4 hours, respectively. The method of radiolabeling, based on the nucleophilic exchange reaction, resulted in a radiochemical yield of 43% and 67% for compounds 3 and 4, respectively. This paper reports on the labeling of etomoxir with radioiodine as {sup 124}I labeled etomoxir may be of great importance in molecular imaging.

  11. Synthesis of deuterated clenbuterol

    Energy Technology Data Exchange (ETDEWEB)

    Joergensen, Ole [Risoe National Lab., Roskilde (Denmark). Solid State Physics Dept.; Egsgaard, Helge; Larsen, Elfinn [Risoe National Lab., Roskilde (Denmark). Science and Technology Dept.

    1996-11-01

    The synthesis of D{sub 9}-clenbuterol (I) and D{sub 3}-clenbuterol (II) is described. D{sub 9}-clenbuterol (I) was prepared from 4-amino-{alpha}-bromo-3, 5-dichloroacetophenone by reaction with D{sub 9}-tert-butylamine followed by reduction of the keto group with NaBH{sub 4}. D{sub 3}-clenbuterol (II) was prepared from 4-amino-{alpha}-tert-butylamino-3, 5-dichloroacetophenone by an exchange reaction of the {alpha}-hydrogens with deuterium followed by reduction of the keto group with NaBD{sub 4}. The eventual products were characterized by mass spectrometry and NMR. (author).

  12. Plasma synthesis of nanopowders

    Energy Technology Data Exchange (ETDEWEB)

    Vollath, Dieter, E-mail: dieter.vollath@nanoconsulting.d [NanoConsulting (Germany)

    2008-12-15

    There is a huge variety of plasma processes for synthesis of nanoparticulate powders. They may be grouped with respect to operating temperature, which is the essential parameter with respect to the properties of the products. In view of industrial production, the highest degree of maturity is found in high temperature processes working under ambient pressure. For products, where well-defined properties are demanded, low temperature microwave plasma processes are best suited. Additionally, these processes allow coating of the produced particles, even with organic phases. Other processes where plasmas are involved, such as laser or flame processes coupled with electric fields have, to some extent, a high potential for development.

  13. Microemulsion Synthesis of Nanoparticles

    Directory of Open Access Journals (Sweden)

    Gotić, M.

    2013-11-01

    Full Text Available Nanoparticles and nanomaterials have wide applications in electronics, physics, material design, being also utilized as sensors, catalysts, and more and more in biomedicine. Microemulsions are an exceptionally suitable medium for the synthesis of nanoparticles due to their thermodynamical stability, great solubility of both polar and nonpolar components, as well as their ability to control the size, dispersity and shape of the particles. This review presents microemulsion techniques for the synthesis of inorganic nanoparticles. It takes place in water-in-oil microemulsions by mixing one microemulsion with a cationic precursor, and the other with a precipitating or reducing agent, or by direct addition of reducing agents or gas (O2, NH3 ili CO2 into microemul sion (Fig. 1. Metal nanoparticles are used as catalysts, sensors, ferrofluids etc. They are produced by reducing the metal cation with a suitable reducing agent. In a similar way, one can prepare nanoparticles of alloys from the metal salts, provided that the metals are mutually soluble. The microemulsion technique is also suitable for depositing nanoparticles onto various surfaces. Highly active catalysts made from nanoparticles of Pt, Pd, Rh and other noble metals may be obtained in this way. Metal oxides and hydroxides may be prepared by hydrolysis or precipitation in the water core of microemulsion. Precipitation can be initiated by adding the base or precipitating agent into the microemulsion with water solution of metal ions. Similarly, nanoparticles may be prepared of sulphides, halogenides, cyanides, carbonates, sulphates and other insoluble metal salts. To prevent oxidation of nanoparticles, especially Fe, the particles are coated with inert metals, oxides, various polymers etc. Coating may provide additional functionality; e.g. coating with gold allows subsequent functionalization with organic compounds containing sulphur, due to the strong Au–S bond. Polymer coatings decrease

  14. Total Synthesis of (-)-Daphenylline.

    Science.gov (United States)

    Yamada, Ryosuke; Adachi, Yohei; Yokoshima, Satoshi; Fukuyama, Tohru

    2016-05-10

    Total synthesis of (-)-daphenylline, a hexacyclic Daphniphyllum alkaloid, was achieved. Construction of the tricyclic DEF ring system was initiated by asymmetric Negishi coupling followed by an intramolecular Friedel-Crafts reaction. Installation of a side chain onto the tricyclic core was carried out through Sonogashira coupling, stereocontrolled Claisen rearrangement by taking advantage of the characteristic conformation of the tricyclic DEF core, and the stereoselective alkylation of a lactone. After the introduction of a glycine unit, the ABC ring system was stereoselectively constructed through intramolecular cycloaddition of the cyclic azomethine ylide. PMID:27062676

  15. [New synthesis empathogenic agents].

    Science.gov (United States)

    Velea, D; Hautefeuille, M; Vazeille, G; Lantran-Davoux, C

    1999-01-01

    The use of synthesis drugs is the object of numerous written articles and TV programs in the last, decade. These synthesis drugs or "designer drugs", are well known for their ability to enhance, reinforce or appease social difficulties and relationships. In the research for empathetic and entactogenic relations one discover an obvious lack of communication and "warmth" in personal or professional relationship. An image of chemical "well being" has become a frequent stereotype of a society with an atrophying of performance and values while supposedly dedicating itself to individual performance. The youths are the first victims of these new drugs, the economical and social environment are the main reinforcing factors of this behaviour. The main characteristic of these drugs, is the non-recognition of their danger, some users go so far as to describe this category of substances as "drugs which are not drugs". As a characteristic, the use of a these synthesis drugs is almost recreative, during the week-end and holiday. The drug addiction is different than that of opiates or cocaine. One can observe some cases of real dependence--corresponding to the DSW IV criterion--when the personality of the users is the main characteristic (narcissic failure, immature personality, family and school problems). Many adverse effects--hypertension, kidney failure, psychoses--were declared. The mass-media has presented many articles concerning Ecstasy (MDMA). This is the most used drug during the rave parties. Its adverse effects are well known and proven. The authors would like to present other more recent synthesis drugs, also known as "analogs". These drugs, a kind of mixture between amphetamine-like (MDMA, MBDB, MDA) and misused medicines (ketamine, gamma OH, atropine) represent a real danger. GHB, 2 CB, HMB, are some of these recent substances. The possibility to procure them on the Web, or to produce them by oneself, add to their danger because of the lack of controls on toxicity

  16. Exploring and Implementing Participatory Action Synthesis

    Science.gov (United States)

    Wimpenny, Katherine; Savin-Baden, Maggi

    2012-01-01

    This article presents participatory action synthesis as a new approach to qualitative synthesis which may be used to facilitate the promotion and use of qualitative research for policy and practice. The authors begin by outlining different forms of qualitative research synthesis and then present participatory action synthesis, a collaborative…

  17. Oxygenates vs. synthesis gas

    Energy Technology Data Exchange (ETDEWEB)

    Kamil Klier; Richard G. Herman; Alessandra Beretta; Maria A. Burcham; Qun Sun; Yeping Cai; Biswanath Roy

    1999-04-01

    Methanol synthesis from H{sub 2}/CO has been carried out at 7.6 MPa over zirconia-supported copper catalysts. Catalysts with nominal compositions of 10/90 mol% and 30/70 mol% Cu/ZrO{sub 2} were used in this study. Additionally, a 3 mol% cesium-doped 10/90 catalyst was prepared to study the effect of doping with heavy alkali, and this promoter greatly increased the methanol productivity. The effects of CO{sub 2} addition, water injection, reaction temperature, and H{sub 2}/C0 ratio have been investigated. Both CO{sub 2} addition to the synthesis gas and cesium doping of the catalyst promoted methanol synthesis, while inhibiting the synthesis of dimethyl ether. Injection of water, however, was found to slightly suppress methanol and dimethyl ether formation while being converted to CO{sub 2} via the water gas shift reaction over these catalysts. There was no clear correlation between copper surface area and catalyst activity. Surface analysis of the tested samples revealed that copper tended to migrate and enrich the catalyst surface. The concept of employing a double-bed reactor with a pronounced temperature gradient to enhance higher alcohol synthesis was explored, and it was found that utilization of a Cs-promoted Cu/ZnO/Cr{sub 2}O{sub 3} catalyst as a first lower temperature bed and a Cs-promoted ZnO/Cr{sub 2}O{sub 3} catalyst as a second high-temperature bed significantly promoted the productivity of 2-methyl-1-propanol (isobutanol) from H{sub 2}/CO synthesis gas mixtures. While the conversion of CO to C{sub 2+} oxygenates over the double-bed configuration was comparable to that observed over the single Cu-based catalyst, major changes in the product distribution occurred by the coupling to the zinc chromite catalyst; that is, the productivity of the C{sub 1}-C{sub 3} alcohols decreased dramatically, and 2-methyl branched alcohols were selectively formed. The desirable methanol/2-methyl oxygenate molar ratios close to 1 were obtained in the present double

  18. Organic Synthesis in Space

    Science.gov (United States)

    Sandford, Scott A.; DeVincenzi, Donald (Technical Monitor)

    2002-01-01

    This talk will review our current understanding of the synthesis of organic molecules in space, with particular emphasis on the synthesis of those compounds that may be of prebiotic interest. The talk will address the possibility that molecules created in the interstellar medium may play a role in the origin and evolution of life on planetary surfaces. The various organic and volatile compounds that are now known or suspected to exist in a variety of space environments (stellar outflows, the diffuse interstellar medium, dense molecular clouds, protostellar nebulae, and planetesimal parent bodies in planetary systems) will be reviewed. This information comes largely from the combined applications of observational infrared and radio spectroscopy, laboratory astrophysical simulations, and theoretical astrochemistry. This will be followed by a discussion of the evidence, largely gathered from the laboratory isotopic study of extraterrestrial materials (meteorites and cosmic dust), that interstellar materials, including organics, can and do survive the transition from the interstellar space into forming stellar systems. Once there, some of this material can be delivered largely unaltered to planetary surfaces where it can play key roles in the origin and subsequent evolution of life.

  19. Transition Texture Synthesis

    Institute of Scientific and Technical Information of China (English)

    Yueh-Yi Lai; Wen-Kai Tai

    2008-01-01

    Synthesis of transition textures is essential for displaying visually acceptable appearances on a terrain. This investigation presents a modified method for synthesizing the transition texture to be tiled on a terrain. All transition pattern types are recognized for a number of input textures. The proposed modified patch-based sampling texture synthesis approach, using the extra feature map of the input source and target textures for patch matching, can synthesize any transition texture on a succession pattern by initializing the output texture using a portion of the source texture enclosed in a transition cut. The transition boundary is further enhanced to improve the visual effect by tracing out the integral texture elements. Either the Game of Life model or Wang tiles method are exploited to present a good-looking profile of successions on a terrain for tiling transition textures. Experimental results indicate that the proposed method requires few input textures, yet synthesizes numerous tileable transition textures, which are useful for obtaining a vivid appearance of a terrain.

  20. Synthesis of Methylaluminoxane

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Methylaluminoxane (MAO) is the most important cocatalyst of metallocene catalysts. In order to raise the hydrolysis reactions repeatability and the yield,we used the pretreated A12(SO4)3 18H2O to synthesize MAO. A few factors which influence the yield and the cocatalytic activity of MAO were discussed. The optimum condition of the reaction was obtained. The yield of MAO was raised from 40% to 49%. Synthesis of MAO: All the apparatus used was oven dried overnight and cooled under highly pure nitrogen atmosphere before use. The synthesis of MAO is carried out according to the procedure described below. 2M TMA/toluene solution was placed in a 200ml pressure balanced funnel. In a tluee necked 500ml round bottomed flask equipped with a teflon magnetic bar, the pretreated A12(SO4)3.18H2O was dispersed in dry toluene. The first neck was fitted with the pressure balanced funnel with a nitrogen outlet. The second neck was connected to nitrogen inlet. The third neck was connected to a thermowell.

  1. Synthesis of Methylaluminoxane

    Institute of Scientific and Technical Information of China (English)

    ZHU; BoChao

    2001-01-01

    Methylaluminoxane (MAO) is the most important cocatalyst of metallocene catalysts. In order to raise the hydrolysis reactions repeatability and the yield,we used the pretreated A12(SO4)3 18H2O to synthesize MAO. A few factors which influence the yield and the cocatalytic activity of MAO were discussed. The optimum condition of the reaction was obtained. The yield of MAO was raised from 40% to 49%.  Synthesis of MAO: All the apparatus used was oven dried overnight and cooled under highly pure nitrogen atmosphere before use. The synthesis of MAO is carried out according to the procedure described below.   2M TMA/toluene solution was placed in a 200ml pressure balanced funnel. In a tluee necked 500ml round bottomed flask equipped with a teflon magnetic bar, the pretreated A12(SO4)3.18H2O was dispersed in dry toluene. The first neck was fitted with the pressure balanced funnel with a nitrogen outlet. The second neck was connected to nitrogen inlet. The third neck was connected to a thermowell.  ……

  2. Synthesis of Lysophospholipids

    Directory of Open Access Journals (Sweden)

    Paola D’Arrigo

    2010-03-01

    Full Text Available New synthetic methods for the preparation of biologically active phospholipids and lysophospholipids (LPLs are very important in solving problems of membrane–chemistry and biochemistry. Traditionally considered just as second-messenger molecules regulating intracellular signalling pathways, LPLs have recently shown to be involved in many physiological and pathological processes such as inflammation, reproduction, angiogenesis, tumorogenesis, atherosclerosis and nervous system regulation. Elucidation of the mechanistic details involved in the enzymological, cell-biological and membrane-biophysical roles of LPLs relies obviously on the availability of structurally diverse compounds. A variety of chemical and enzymatic routes have been reported in the literature for the synthesis of LPLs: the enzymatic transformation of natural glycerophospholipids (GPLs using regiospecific enzymes such as phospholipases A1 (PLA1, A2 (PLA2 phospholipase D (PLD and different lipases, the coupling of enzymatic processes with chemical transformations, the complete chemical synthesis of LPLs starting from glycerol or derivatives. In this review, chemo-enzymatic procedures leading to 1- and 2-LPLs will be described.

  3. Towards Automated System Synthesis Using SCIDUCTION

    OpenAIRE

    Jha, Susmit Kumar

    2011-01-01

    Automated synthesis of systems that are correct by construction has been a long-standing goal of computer science. Synthesis is a creative task and requires human intuition and skill. Its complete automation is currently beyond the capacity of programs that do automated reasoning. However, there is a pressing need for tools and techniques that can automate non-intuitive and error-prone synthesis tasks. This thesis proposes a novel synthesis approach to solve such tasks in the synthesis of pro...

  4. Flow “Fine” Synthesis: High Yielding and Selective Organic Synthesis by Flow Methods

    OpenAIRE

    Kobayashi, Shū

    2015-01-01

    Abstract The concept of flow “fine” synthesis, that is, high yielding and selective organic synthesis by flow methods, is described. Some examples of flow “fine” synthesis of natural products and APIs are discussed. Flow methods have several advantages over batch methods in terms of environmental compatibility, efficiency, and safety. However, synthesis by flow methods is more difficult than synthesis by batch methods. Indeed, it has been considered that synthesis by flow methods can be appli...

  5. Combinatorial materials synthesis

    Directory of Open Access Journals (Sweden)

    Ichiro Takeuchi

    2005-10-01

    Full Text Available The pace at which major technological changes take place is often dictated by the rate at which new materials are discovered, and the timely arrival of new materials has always played a key role in bringing advances to our society. It is no wonder then that the so-called combinatorial or high-throughput strategy has been embraced by practitioners of materials science in virtually every field. High-throughput experimentation allows simultaneous synthesis and screening of large arrays of different materials. Pioneered by the pharmaceutical industry, the combinatorial method is now widely considered to be a watershed in accelerating the discovery and optimization of new materials1–5.

  6. Isobutanol synthesis from syngas

    Energy Technology Data Exchange (ETDEWEB)

    Falter, W.; Finkeldei, C.H.; Jaeger, B.; Keim, W.; Verkerk, K.A.N. [Institut fuer Technische Chemie und Petrolchemie der Rheinisch-Westfaelischen Technischen Hochschule Aachen, Aachen (Germany)

    1998-12-31

    The increased demand for MTBE (methyl-t-butyl ether) as gasoline additive has attracted attention to alternative pathways for their production. Within this respect the synthesis of higher alcohols by CO hydrogenation has gained new interest, since the selective production of isobutanol-methanol mixtures could offer a possible route. Using a Zr/Zn/Mn/K/Pd catalyst at 400-450 C, 250 bar pressure, 20.000 GHSV/h{sup -1} space time yields of 700-750 g {center_dot} 1{sup -1} {center_dot} h{sup -1} of isobutanol could be obtained. A comparison was made using a fixed bed (tubular) and a CSTR reactor system. 3 refs.

  7. De Novo Glutamine Synthesis

    Directory of Open Access Journals (Sweden)

    Qiao He MD

    2016-04-01

    Full Text Available Purpose: The aim of this study was to investigate the role of de novo glutamine (Gln synthesis in the proliferation of C6 glioma cells and its detection with 13N-ammonia. Methods: Chronic Gln-deprived C6 glioma (0.06C6 cells were established. The proliferation rates of C6 and 0.06C6 cells were measured under the conditions of Gln deprivation along with or without the addition of ammonia or glutamine synthetase (GS inhibitor. 13N-ammonia uptake was assessed in C6 cells by gamma counting and in rats with C6 and 0.06C6 xenografts by micro–positron emission tomography (PET scanning. The expression of GS in C6 cells and xenografts was assessed by Western blotting and immunohistochemistry, respectively. Results: The Gln-deprived C6 cells showed decreased proliferation ability but had a significant increase in GS expression. Furthermore, we found that low concentration of ammonia was sufficient to maintain the proliferation of Gln-deprived C6 cells, and 13N-ammonia uptake in C6 cells showed Gln-dependent decrease, whereas inhibition of GS markedly reduced the proliferation of C6 cells as well as the uptake of 13N-ammoina. Additionally, microPET/computed tomography exhibited that subcutaneous 0.06C6 xenografts had higher 13N-ammonia uptake and GS expression in contrast to C6 xenografts. Conclusion: De novo Gln synthesis through ammonia–glutamate reaction plays an important role in the proliferation of C6 cells. 13N-ammonia can be a potential metabolic PET tracer for Gln-dependent tumors.

  8. Instrument Synthesis and Analysis Laboratory

    Science.gov (United States)

    Wood, H. John

    2004-01-01

    The topics addressed in this viewgraph presentation include information on 1) Historic instruments at Goddard; 2) Integrated Design Capability at Goddard; 3) The Instrument Synthesis and Analysis Laboratory (ISAL).

  9. Green chemistry for nanoparticle synthesis.

    Science.gov (United States)

    Duan, Haohong; Wang, Dingsheng; Li, Yadong

    2015-08-21

    The application of the twelve principles of green chemistry in nanoparticle synthesis is a relatively new emerging issue concerning the sustainability. This field has received great attention in recent years due to its capability to design alternative, safer, energy efficient, and less toxic routes towards synthesis. These routes have been associated with the rational utilization of various substances in the nanoparticle preparations and synthetic methods, which have been broadly discussed in this tutorial review. This article is not meant to provide an exhaustive overview of green synthesis of nanoparticles, but to present several pivotal aspects of synthesis with environmental concerns, involving the selection and evaluation of nontoxic capping and reducing agents, the choice of innocuous solvents and the development of energy-efficient synthetic methods.

  10. Vanillin Synthesis from 4-Hydroxybenzaldehyde

    Science.gov (United States)

    Taber, Douglass F.; Patel, Shweta; Hambleton, Travis M.; Winkel, Emma E.

    2007-01-01

    A regioselective, safe and efficient method for the synthesis of vanillin from 4-hydroxybenzaldehyde is being described. The vanillin derived from the process is cheap and can be used as a flavor or in the paper industry.

  11. Total synthesis of solanoeclepin A

    Science.gov (United States)

    Tanino, Keiji; Takahashi, Motomasa; Tomata, Yoshihide; Tokura, Hiroshi; Uehara, Taketo; Narabu, Takashi; Miyashita, Masaaki

    2011-06-01

    Cyst nematodes are troublesome parasites that live on, and destroy, a range of important host vegetable plants. Damage caused by the potato cyst nematode has now been reported in over 50 countries. One approach to eliminating the problem is to stimulate early hatching of the nematodes, but key hatching stimuli are not naturally available in sufficient quantities to do so. Here, we report the first chemical synthesis of solanoeclepin A, the key hatch-stimulating substance for potato cyst nematode. The crucial steps in our synthesis are an intramolecular cyclization reaction for construction of the highly strained tricyclo[5.2.1.01,6]decane skeleton (DEF ring system) and an intramolecular Diels-Alder reaction of a furan derivative for the synthesis of the ABC carbon framework. The present synthesis has the potential to contribute to addressing one of the critical food issues of the twenty-first century.

  12. Green chemistry for nanoparticle synthesis.

    Science.gov (United States)

    Duan, Haohong; Wang, Dingsheng; Li, Yadong

    2015-08-21

    The application of the twelve principles of green chemistry in nanoparticle synthesis is a relatively new emerging issue concerning the sustainability. This field has received great attention in recent years due to its capability to design alternative, safer, energy efficient, and less toxic routes towards synthesis. These routes have been associated with the rational utilization of various substances in the nanoparticle preparations and synthetic methods, which have been broadly discussed in this tutorial review. This article is not meant to provide an exhaustive overview of green synthesis of nanoparticles, but to present several pivotal aspects of synthesis with environmental concerns, involving the selection and evaluation of nontoxic capping and reducing agents, the choice of innocuous solvents and the development of energy-efficient synthetic methods. PMID:25615873

  13. Synthesis in land change science

    DEFF Research Database (Denmark)

    Magliocca, Nicholas R.; Rudel, Thomas K.; Verburg, Peter H.;

    2015-01-01

    Global and regional economic and environmental changes are increasingly influencing local land-use, livelihoods, and ecosystems. At the same time, cumulative local land changes are driving global and regional changes in biodiversity and the environment. To understand the causes and consequences...... of these changes, land change science (LCS) draws on a wide array synthetic and meta-study techniques to generate global and regional knowledge from local case studies of land change. Here, we review the characteristics and applications of synthesis methods in LCS and assess the current state of synthetic research...... based on a meta-analysis of synthesis studies from 1995 to 2012. Publication of synthesis research is accelerating, with a clear trend toward increasingly sophisticated and quantitative methods, including meta-analysis. Detailed trends in synthesis objectives, methods, and land change phenomena...

  14. Principles of digital image synthesis

    CERN Document Server

    Glassner, Andrew S

    1995-01-01

    Image synthesis, or rendering, is a field of transformation: it changesgeometry and physics into meaningful images. Because the most popularalgorithms frequently change, it is increasingly important for researchersand implementors to have a basic understanding of the principles of imagesynthesis. Focusing on theory, Andrew Glassner provides a comprehensiveexplanation of the three core fields of study that come together to formdigital image synthesis: the human visual system, digital signalprocessing, and the interaction of matter and light. Assuming no more thana basic background in calculus,

  15. Kojic acid in organic synthesis

    OpenAIRE

    ZIRAK, MARYAM; Eftekhari-Sis, Bagher

    2015-01-01

    The reactions of kojic acid in organic synthesis are reviewed. The aim of this review is to cover the literature up to the end of 2014, showing the distribution of publications involving kojic acid chemistry in the synthesis of various pyrone containing compounds, pyridine and pyridone heterocycles, and also other organic compounds. First, introductory text about the preparation, biological, and industrial applications, and the chemical properties of kojic acid is given. Then its uses in orga...

  16. Diastereoselective Total Synthesis of (-)-Galiellalactone.

    Science.gov (United States)

    Kim, Taewoo; Han, Young Taek; An, Hongchan; Kim, Kyeojin; Lee, Jeeyeon; Suh, Young-Ger

    2015-12-18

    An enantioselective total synthesis of (-)-galiellalactone has been accomplished. The key features of the synthesis involve the highly stereoselective construction of the cis-trisubstituted cyclopentane intermediate by a Pd(0)-catalyzed cyclization, the stereospecific introduction of an angular hydroxyl group by Riley oxidation, and the efficient construction of the tricyclic system of (-)-galiellalactone via a combination of diastereoselective Hosomi-Sakurai crotylation and ring-closing metathesis (RCM). PMID:26544529

  17. Synthesis of new xanthene derivatives

    OpenAIRE

    Kotaskova, Michaela

    2012-01-01

    Xanthene dyes, including fluorescein, are a well-known class of fluorescent dyes, which have widespread applications in natural sciences. The synthesis of xanthene derivatives via acid catalyzed condensation of substituted phenols with phthalic anhydride, to afford the asymmetric derivatives, is well established. The high temperature, harsh reaction conditions and often low yields make this method less convenient. The synthesis of xanthene dyes by direct modification of the fluorophore moiety...

  18. Essentials of inorganic materials synthesis

    CERN Document Server

    Rao, C N R

    2015-01-01

    This compact handbook describes all the important methods of synthesis employed today for synthesizing inorganic materials. Some features: Focuses on modern inorganic materials with applications in nanotechnology, energy materials, and sustainability Synthesis is a crucial component of materials science and technology; this book provides a simple introduction as well as an updated description of methods Written in a very simple style, providing references to the literature to get details of the methods of preparation when required

  19. Gold-Catalyzed Synthesis of Heterocycles

    Science.gov (United States)

    Arcadi, Antonio

    2014-04-01

    The following sections are included: * Introduction * Synthesis of Heterocycles via Gold-Catalyzed Heteroatom Addition to Unsaturated C-C Bonds * Synthesis of Heterocyclic Derivatives through Gold-Catalyzed Cyclization of Polyunsaturated Compounds * Synthesis of Heterocyclic Compounds via α-Oxo Gold Carbenoid * Synthesis of Heterocyclic Derivatives through Gold-Catalyzed Cycloaddition Reactions * Synthesis of Heterocyclic Derivatives through Gold-Catalyzed Activation of Carbonyl Groups and Alcohols * Synthesis of Heterocyclic Compounds through Gold-Mediated C-H Bond Functionalization * Gold-Catalyzed Domino Cyclization/Oxidative Coupling Reactions * Conclusions * References

  20. Synthesis of ferroelectric nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Roervik, Per Martin

    2008-12-15

    The increasing miniaturization of electric and mechanical components makes the synthesis and assembly of nanoscale structures an important step in modern technology. Functional materials, such as the ferroelectric perovskites, are vital to the integration and utility value of nanotechnology in the future. In the present work, chemical methods to synthesize one-dimensional (1D) nanostructures of ferroelectric perovskites have been studied. To successfully and controllably make 1D nanostructures by chemical methods it is very important to understand the growth mechanism of these nanostructures, in order to design the structures for use in various applications. For the integration of 1D nanostructures into devices it is also very important to be able to make arrays and large-area designed structures from the building blocks that single nanostructures constitute. As functional materials, it is of course also vital to study the properties of the nanostructures. The characterization of properties of single nanostructures is challenging, but essential to the use of such structures. The aim of this work has been to synthesize high quality single-crystalline 1D nanostructures of ferroelectric perovskites with emphasis on PbTiO3 , to make arrays or hierarchical nanostructures of 1D nanostructures on substrates, to understand the growth mechanisms of the 1D nanostructures, and to investigate the ferroelectric and piezoelectric properties of the 1D nanostructures. In Paper I, a molten salt synthesis route, previously reported to yield BaTiO3 , PbTiO3 and Na2Ti6O13 nanorods, was re-examined in order to elucidate the role of volatile chlorides. A precursor mixture containing barium (or lead) and titanium was annealed in the presence of NaCl at 760 degrees Celsius or 820 degrees Celsius. The main products were respectively isometric nanocrystalline BaTiO3 and PbTiO3. Nanorods were also detected, but electron diffraction revealed that the composition of the nanorods was

  1. Synthesis of Modified Methylaluminoxane

    Institute of Scientific and Technical Information of China (English)

    Zhu Bo-chao; Zhao Xu-tao; Yin Yuan-qi; Wei Shao-yi

    2004-01-01

    Methylaluminoxane (MAO) is one of the most important cocatalysts of metallocene catalysts. The yield and activity of MAO is low when using Al2(SO4)3 nH2O and other inorganic hydrates to synthesize methylaluminoxane. The repeatability of this reaction is not good. The product cost is very high because one of the raw materials (Trimethylaluminium, TMA) to prepare MAO is very expensive. In addition, on standing, MAO toluene solution tends to gel. Gelled MAO can not be used to prepare supported metallocene catalyets.With the development of gas phase and slurry polymerization of olefine by metallocene catalysts,the application of supported metallocene catalysts becomes more and more important.This paper relates to the use of trimethylaluminium (TMA), tri-isobutylaluminium(TIBA) and silica gel containing from about 4 to about 22 percent by weight absorbed water to synthesize modified methylaluminoxane (MMAO). This method, which integrates synthesis and supporting of MMAO, simplify the preparing process of metallocene catalysts. By using this method, the yield and activity of modified methylaluminoxane is higher than using Al2(SO4)3 nH2O and other inorganic hydrates, and what is more, not only the product cost is lowered, but also gelled MAO is avoided. In addition, the repeatability of this reaction is much better because TIBA is stabler than TMA.Synthesis of Modified MAO: A one liter three neck flask equipped with a magnetic stirring bar and a constant pressure funnel was charged with 250ml of dried and degassed toluene. 60g of undehydrated silica gel (Davison 955) which contains 12 weight percent absorbed water was added into the flask. The resulting mixture was stirred at -10℃ for 30 minutes. Thereafter 90ml of trimethylaluminum/toluene solution (2.0M) was dropped slowly into the flask in 60 minutes. The resulting mixture was allowed to react under stirring at -10℃ for 1hours, then at 0℃ for 1 hours,then at ambient temperature for 1 hours and finally at 40

  2. Arctic freshwater synthesis: Introduction

    Science.gov (United States)

    Prowse, T.; Bring, A.; Mârd, J.; Carmack, E.

    2015-11-01

    In response to a joint request from the World Climate Research Program's Climate and Cryosphere Project, the International Arctic Science Committee, and the Arctic Council's Arctic Monitoring and Assessment Program, an updated scientific assessment has been conducted of the Arctic Freshwater System (AFS), entitled the Arctic Freshwater Synthesis (AFSΣ). The major reason for joint request was an increasing concern that changes to the AFS have produced, and could produce even greater, changes to biogeophysical and socioeconomic systems of special importance to northern residents and also produce extra-Arctic climatic effects that will have global consequences. Hence, the key objective of the AFSΣ was to produce an updated, comprehensive, and integrated review of the structure and function of the entire AFS. The AFSΣ was organized around six key thematic areas: atmosphere, oceans, terrestrial hydrology, terrestrial ecology, resources and modeling, and the review of each coauthored by an international group of scientists and published as separate manuscripts in this special issue of Journal of Geophysical Research-Biogeosciences. This AFSΣ—Introduction reviews the motivations for, and foci of, previous studies of the AFS, discusses criteria used to define the domain of the AFS, and details key characteristics of the definition adopted for the AFSΣ.

  3. Synthesis of P005091

    Directory of Open Access Journals (Sweden)

    Ping YU

    2016-06-01

    Full Text Available To improve the synthesis method of P005091 (1-(5-((2,3-dichlorophenyl thio-4-nitro-2-thienyl ethanone, with 2-chlorothiophene as the starting material, acetyl chloride as the acetylation reagent and aluminium trichloride as the catalyst, acetyl is introduced in the 5th position of 2-chlorothiophene to get 2-acetyl-5-chlorothiophene (compound 2, and the yield is 91%; then with concentrated sulfuric acid as solvent and mixed acid as nitrating agent, 5-acetyl-2-chloro-3-nitrothiophene (compound 3 is obtained by nitration reaction with compound 2, and the yield is 64%; thioetherfication reaction of compound 3 and 2,3-dichlorobenzenethiol in DMF solution under the function of potassium carbonate takes place to obtain the target product P005091, and the yield is 76%. The structure of P005091 is confirmed by mp, 1H-NMR, 13C-NMR and MS, and the overall yield is 44%. The improved method has the advantages of low cost, simple operation, and a milder reaction condition compared with the former references, avoiding using the reagent with higher toxicity, and high yield on the premise that the product purity is assured.

  4. Control Augmented Structural Synthesis

    Science.gov (United States)

    Lust, Robert V.; Schmit, Lucien A.

    1988-01-01

    A methodology for control augmented structural synthesis is proposed for a class of structures which can be modeled as an assemblage of frame and/or truss elements. It is assumed that both the plant (structure) and the active control system dynamics can be adequately represented with a linear model. The structural sizing variables, active control system feedback gains and nonstructural lumped masses are treated simultaneously as independent design variables. Design constraints are imposed on static and dynamic displacements, static stresses, actuator forces and natural frequencies to ensure acceptable system behavior. Multiple static and dynamic loading conditions are considered. Side constraints imposed on the design variables protect against the generation of unrealizable designs. While the proposed approach is fundamentally more general, here the methodology is developed and demonstrated for the case where: (1) the dynamic loading is harmonic and thus the steady state response is of primary interest; (2) direct output feedback is used for the control system model; and (3) the actuators and sensors are collocated.

  5. Accuracy of results with NASTRAN modal synthesis

    Science.gov (United States)

    Herting, D. N.

    1978-01-01

    A new method for component mode synthesis was developed for installation in NASTRAN level 17.5. Results obtained from the new method are presented, and these results are compared with existing modal synthesis methods.

  6. Applied synthesis and characterisation of nanoparticles

    OpenAIRE

    Bear, J C

    2014-01-01

    This thesis covers three areas of development of nanomaterials synthesis; namely the synthesis of superhydrophobic polymer-nanoparticle composites (chapter 3), the synthesis of doped quantum dots for catalysis and photoluminescence enhancement (chapter 4) and the synthesis of magnetic iron oxide nanoparticles from inexpensive, readily available reagents (chapter 5). Details of characterisation and analytical techniques and synthetic methods used are given in chapter 2, and the thesis summaris...

  7. Synthesis and Characterization of Multithiouracils

    Institute of Scientific and Technical Information of China (English)

    WANG Wei; LIU Hui-Min; ZHANG Wei; ZHANG Wen-Qin

    2003-01-01

    @@ Alkylation of bases group of nucleic acid, thymine and uracil, has attracted great attention. In order to investigate the intermolecular interactions, [1,2] and the photoreactions[3,4] between bases group of nucleic acid, many studies were focused on the synthesis of bisbases in the formation of B-(CH2)n-B (B′) in which trimethylene was commonly used as linker. Thiouracil is an important derivative of nucleic acid bases, and it can interfere with the synthesis of thyroxine, especially in the treatment of hyperthyroidism and angina. However, to our knowledge, the synthesis of bisthiouracils, even trithiouracils, using flexible or rigid linkers has not been reported. Herein, we have synthesized eight thiouracil derivatives by nucleophilic reaction between thiouracil and varied bromides. All the compounds have been characterized by IR, 1H NMR and element analysis.

  8. A Short Synthesis of (+)-Cyclophellitol

    DEFF Research Database (Denmark)

    Hansen, Flemming Gundorph; Bundgaard, Eva; Madsen, Robert

    2005-01-01

    A new synthesis of (+)-cyclophellitol, a potent b-glucosidase inhibitor, has been completed in nine steps from D-xylose. The key transformations involve a zinc-mediated fragmentation of benzyl-protected methyl 5-deoxy-5-iodo-xylofuranoside followed by a highly diastereoselective indium-mediated c......A new synthesis of (+)-cyclophellitol, a potent b-glucosidase inhibitor, has been completed in nine steps from D-xylose. The key transformations involve a zinc-mediated fragmentation of benzyl-protected methyl 5-deoxy-5-iodo-xylofuranoside followed by a highly diastereoselective indium......-mediated coupling with ethyl 4-bromocrotonate. Subsequent ring-closing olefin metathesis, ester reduction, olefin epoxidation, and deprotection then afford the natural product. This constitutes the shortest synthesis of (+)-cyclophellitol reported to date....

  9. Structural synthesis of parallel robots

    CERN Document Server

    Gogu, Grigore

    This book represents the fifth part of a larger work dedicated to the structural synthesis of parallel robots. The originality of this work resides in the fact that it combines new formulae for mobility, connectivity, redundancy and overconstraints with evolutionary morphology in a unified structural synthesis approach that yields interesting and innovative solutions for parallel robotic manipulators.  This is the first book on robotics that presents solutions for coupled, decoupled, uncoupled, fully-isotropic and maximally regular robotic manipulators with Schönflies motions systematically generated by using the structural synthesis approach proposed in Part 1.  Overconstrained non-redundant/overactuated/redundantly actuated solutions with simple/complex limbs are proposed. Many solutions are presented here for the first time in the literature. The author had to make a difficult and challenging choice between protecting these solutions through patents and releasing them directly into the public domain. T...

  10. Sustainable Process Synthesis-Intensification

    DEFF Research Database (Denmark)

    Babi, Deenesh Kavi; Holtbruegge, Johannes; Lutze, Philip;

    2014-01-01

    Sustainable process design can be achieved by performing process synthesis and process intensification together. This approach first defines a design target through a sustainability analysis and then finds design alternatives that match the target through process intensification. A systematic......, multi-stage framework for process synthesis- intensification that identifies more sustainable process designs has been developed. At stages 1-2, the working scale is at the level of unit operations, where a base case design is identified and analyzed with respect to sustainability metrics. At stages 3......-4, the working scales are at the levels of unit operations, tasks and phenomena. Here, first intensified flowsheet alternatives are generated through a tasked-based process synthesis method where tasks performed in unit operations are identified, analyzed and recombined through a means-ends analysis. Next...

  11. The KTH synthesis of singing

    Directory of Open Access Journals (Sweden)

    Johan Sundberg

    2006-01-01

    Full Text Available This is an overview of the work with synthesizing singing that has been carried out at the Speech Music Hearing Department, KTH since 1977. The origin of the work, a hardware synthesis machine, is described and some aspects of the control program, a modified version of a text-to-speech conversion system are reviewed. Three applications are described in which the synthesis system has paved the way for investigations of specific aspects of the singing voice. One concerns the perceptual relevance of the center frequency of the singer's formant, one deals with characteristics of an ugly voice, and one regards intonation. The article is accompanied by 18 sound examples, several of which were not published before. Finally, limitations and advantages of singing synthesis are discussed.

  12. Sterol synthesis in diverse bacteria

    Directory of Open Access Journals (Sweden)

    Jeremy H Wei

    2016-06-01

    Full Text Available Sterols are essential components of eukaryotic cells whose biosynthesis and function has been studied extensively. Sterols are also recognized as the diagenetic precursors of steranes preserved in sedimentary rocks where they can function as geological proxies for eukaryotic organisms and/or aerobic metabolisms and environments. However, production of these lipids is not restricted to the eukaryotic domain as a few bacterial species also synthesize sterols. Phylogenomic studies have identified genes encoding homologs of sterol biosynthesis proteins in the genomes of several additional species, indicating that sterol production may be more widespread in the bacterial domain than previously thought. Although the occurrence of sterol synthesis genes in a genome indicates the potential for sterol production, it provides neither conclusive evidence of sterol synthesis nor information about the composition and abundance of basic and modified sterols that are actually being produced. Here, we coupled bioinformatics with lipid analyses to investigate the scope of bacterial sterol production. We identified oxidosqualene cyclase (Osc, which catalyzes the initial cyclization of oxidosqualene to the basic sterol structure, in 34 bacterial genomes from 5 phyla (Bacteroidetes, Cyanobacteria, Planctomycetes, Proteobacteria and Verrucomicrobia and in 176 metagenomes. Our data indicate that bacterial sterol synthesis likely occurs in diverse organisms and environments and also provides evidence that there are as yet uncultured groups of bacterial sterol producers. Phylogenetic analysis of bacterial and eukaryotic Osc sequences confirmed a complex evolutionary history of sterol synthesis in this domain. Finally, we characterized the lipids produced by Osc-containing bacteria and found that we could generally predict the ability to synthesize sterols. However, predicting the final modified sterol based on our current knowledge of sterol synthesis was difficult

  13. Sterol Synthesis in Diverse Bacteria.

    Science.gov (United States)

    Wei, Jeremy H; Yin, Xinchi; Welander, Paula V

    2016-01-01

    Sterols are essential components of eukaryotic cells whose biosynthesis and function has been studied extensively. Sterols are also recognized as the diagenetic precursors of steranes preserved in sedimentary rocks where they can function as geological proxies for eukaryotic organisms and/or aerobic metabolisms and environments. However, production of these lipids is not restricted to the eukaryotic domain as a few bacterial species also synthesize sterols. Phylogenomic studies have identified genes encoding homologs of sterol biosynthesis proteins in the genomes of several additional species, indicating that sterol production may be more widespread in the bacterial domain than previously thought. Although the occurrence of sterol synthesis genes in a genome indicates the potential for sterol production, it provides neither conclusive evidence of sterol synthesis nor information about the composition and abundance of basic and modified sterols that are actually being produced. Here, we coupled bioinformatics with lipid analyses to investigate the scope of bacterial sterol production. We identified oxidosqualene cyclase (Osc), which catalyzes the initial cyclization of oxidosqualene to the basic sterol structure, in 34 bacterial genomes from five phyla (Bacteroidetes, Cyanobacteria, Planctomycetes, Proteobacteria, and Verrucomicrobia) and in 176 metagenomes. Our data indicate that bacterial sterol synthesis likely occurs in diverse organisms and environments and also provides evidence that there are as yet uncultured groups of bacterial sterol producers. Phylogenetic analysis of bacterial and eukaryotic Osc sequences confirmed a complex evolutionary history of sterol synthesis in this domain. Finally, we characterized the lipids produced by Osc-containing bacteria and found that we could generally predict the ability to synthesize sterols. However, predicting the final modified sterol based on our current knowledge of sterol synthesis was difficult. Some bacteria

  14. Sterol Synthesis in Diverse Bacteria.

    Science.gov (United States)

    Wei, Jeremy H; Yin, Xinchi; Welander, Paula V

    2016-01-01

    Sterols are essential components of eukaryotic cells whose biosynthesis and function has been studied extensively. Sterols are also recognized as the diagenetic precursors of steranes preserved in sedimentary rocks where they can function as geological proxies for eukaryotic organisms and/or aerobic metabolisms and environments. However, production of these lipids is not restricted to the eukaryotic domain as a few bacterial species also synthesize sterols. Phylogenomic studies have identified genes encoding homologs of sterol biosynthesis proteins in the genomes of several additional species, indicating that sterol production may be more widespread in the bacterial domain than previously thought. Although the occurrence of sterol synthesis genes in a genome indicates the potential for sterol production, it provides neither conclusive evidence of sterol synthesis nor information about the composition and abundance of basic and modified sterols that are actually being produced. Here, we coupled bioinformatics with lipid analyses to investigate the scope of bacterial sterol production. We identified oxidosqualene cyclase (Osc), which catalyzes the initial cyclization of oxidosqualene to the basic sterol structure, in 34 bacterial genomes from five phyla (Bacteroidetes, Cyanobacteria, Planctomycetes, Proteobacteria, and Verrucomicrobia) and in 176 metagenomes. Our data indicate that bacterial sterol synthesis likely occurs in diverse organisms and environments and also provides evidence that there are as yet uncultured groups of bacterial sterol producers. Phylogenetic analysis of bacterial and eukaryotic Osc sequences confirmed a complex evolutionary history of sterol synthesis in this domain. Finally, we characterized the lipids produced by Osc-containing bacteria and found that we could generally predict the ability to synthesize sterols. However, predicting the final modified sterol based on our current knowledge of sterol synthesis was difficult. Some bacteria

  15. Asymmetric Formal Synthesis of Azadirachtin.

    Science.gov (United States)

    Mori, Naoki; Kitahara, Takeshi; Mori, Kenji; Watanabe, Hidenori

    2015-12-01

    An asymmetric formal synthesis of azadirachtin, a potent insect antifeedant, was accomplished in 30 steps to Ley's synthetic intermediate (longest linear sequence). The synthesis features: 1) rapid access to the optically active right-hand segment starting from the known 5-hydroxymethyl-2-cyclopentenone scaffold; 2) construction of the B and E rings by a key intramolecular tandem radical cyclization; 3) formation of the hemiacetal moiety in the C ring through the α-oxidation of the six-membered lactone followed by methanolysis. PMID:26474211

  16. Combustion synthesis method and products

    Science.gov (United States)

    Holt, J.B.; Kelly, M.

    1993-03-30

    Disclosed is a method of producing dense refractory products, comprising: (a) obtaining a quantity of exoergic material in powder form capable of sustaining a combustion synthesis reaction; (b) removing absorbed water vapor therefrom; (c) cold-pressing said material into a formed body; (d) plasma spraying said formed body with a molten exoergic material to form a coat thereon; and (e) igniting said exoergic coated formed body under an inert gas atmosphere and pressure to produce self-sustained combustion synthesis. Also disclosed are products produced by the method.

  17. Ferroic materials synthesis and applications

    CERN Document Server

    Virk, Hardev Singh

    2015-01-01

    Ferroics is the generic name given to the study of ferromagnets, ferroelectrics, and ferroelastics. The basis of this study is to understand the large changes in physical characteristics that occur over a very narrow temperature range. In recent years, a new class of ferroic materials has been attracting increased interest. These multiferroics exhibit more than one ferroic property simultaneously in a single phase. The present volume: ""Ferroic Materials: Synthesis and Applications"" has ten Chapters, spread over areas as diverse as Magnetic Oxide Nanomaterials, Ferrites Synthesis, Hexaferrite

  18. Heterogeneous photocatalysts in organic synthesis

    International Nuclear Information System (INIS)

    The review deals with the application of inorganic semiconductors in organic synthesis. Although the majority of reported reactions still aim at the photocatalytic decomposition of organic compounds, the number of examples in synthetic applications is growing. The principal mechanisms of heterogeneous semiconductor photocatalysis are considered and examples illustrating the use of inorganic semiconductors in organic synthesis are given. The discussion is arranged according to the required excitation wavelength (UV or visible light) and to the new bond that is formed (carbon–carbon or carbon–heteroatom bond). The bibliography includes 47 references

  19. First total synthesis of Boehmenan

    Indian Academy of Sciences (India)

    Yamu Xia; Xiaoli Dai; Haixin Liu; Chen Chai

    2014-05-01

    The first total synthesis of dilignan Boehmenan has been achieved. A biomimetic oxidative coupling of the ferulic acid methyl ester in the presence of silver oxide is the crucial step in the synthesis sequence, generating the dihydrobenzofuran skeleton. Hydroxyl group was protected with DHP and reducted with LiAlH4 to afford the intermediate diol. The diol was condensated with the derivative of ferulic acid, then removed the protecting groups, to get Boehmenan. Meanwhile, a study on the ring-opening reaction of the intermediate dihydrobenzofuran neolignan under base conditions was described.

  20. Synthesis and Characterisation of Nanomaterials

    Directory of Open Access Journals (Sweden)

    P. Saravanan

    2008-07-01

    Full Text Available Development of synthesis protocols for realising nanomaterials over a range of sizes, shapes,and chemical compositions is an important aspect of nanotechnology. The remarkable size-dependent physico-chemical properties of nanoparticles have fascinated and inspired researchactivity in this direction. This paper describes some aspects on synthesis and characterisationof nanoparticles of metals, metal alloys, and oxides, either in the form of thin films or bulk shapes.A brief discussion on processing of two-phase nanocomposite magnets is also presented.Defence Science Journal, 2008, 58(4, pp.504-516, DOI:http://dx.doi.org/10.14429/dsj.58.1671

  1. Plant mediated green synthesis: modified approaches

    Science.gov (United States)

    Das, Ratul Kumar; Brar, Satinder Kaur

    2013-10-01

    Plant mediated green synthesis of different metallic nanoparticles has emerged as one of the options for implementation of green chemistry principles, and successfully made an important contribution towards green nanotechnology. However, beyond the synthesis and application aspects, the science of green synthesis has carried some wrong perceptions in an unforeseen fashion. In this review, some of the key issues related to the green synthesis of metallic nanoparticles employing plants as reducing/capping agents have been addressed. Random selection of plants and its overall impact on the different aspects of green synthesis have been discussed. Emphasis is given to the setting of some standard selection criteria to be adopted for selecting a plant for use in green synthesis. How selection of a plant can positively or negatively influence both procedure and products of a green synthesis process is the prime concern of this article. In addition to selection, the key issue of biocompatibility associated with green synthesized metallic nanoparticles has been considered. Both selection of plant and biocompatibility were reconsidered for their minute details in terms of synthesis, analysis and data interpretation in the green synthesis approach. The key factors capable of fine tuning the core meaning of ``green'' in the synthesis of any metallic nanoparticles were taken into consideration. This article is an effort towards keeping the core meaning of green synthesis.

  2. Analysis and synthesis of laughter

    Science.gov (United States)

    Sundaram, Shiva; Narayanan, Shrikanth

    2004-10-01

    There is much enthusiasm in the text-to-speech community for synthesis of emotional and natural speech. One idea being proposed is to include emotion dependent paralinguistic cues during synthesis to convey emotions effectively. This requires modeling and synthesis techniques of various cues for different emotions. Motivated by this, a technique to synthesize human laughter is proposed. Laughter is a complex mechanism of expression and has high variability in terms of types and usage in human-human communication. People have their own characteristic way of laughing. Laughter can be seen as a controlled/uncontrolled physiological process of a person resulting from an initial excitation in context. A parametric model based on damped simple harmonic motion to effectively capture these diversities and also maintain the individuals characteristics is developed here. Limited laughter/speech data from actual humans and synthesis ease are the constraints imposed on the accuracy of the model. Analysis techniques are also developed to determine the parameters of the model for a given individual or laughter type. Finally, the effectiveness of the model to capture the individual characteristics and naturalness compared to real human laughter has been analyzed. Through this the factors involved in individual human laughter and their importance can be better understood.

  3. Robust Face Sketch Style Synthesis.

    Science.gov (United States)

    Shengchuan Zhang; Xinbo Gao; Nannan Wang; Jie Li

    2016-01-01

    Heterogeneous image conversion is a critical issue in many computer vision tasks, among which example-based face sketch style synthesis provides a convenient way to make artistic effects for photos. However, existing face sketch style synthesis methods generate stylistic sketches depending on many photo-sketch pairs. This requirement limits the generalization ability of these methods to produce arbitrarily stylistic sketches. To handle such a drawback, we propose a robust face sketch style synthesis method, which can convert photos to arbitrarily stylistic sketches based on only one corresponding template sketch. In the proposed method, a sparse representation-based greedy search strategy is first applied to estimate an initial sketch. Then, multi-scale features and Euclidean distance are employed to select candidate image patches from the initial estimated sketch and the template sketch. In order to further refine the obtained candidate image patches, a multi-feature-based optimization model is introduced. Finally, by assembling the refined candidate image patches, the completed face sketch is obtained. To further enhance the quality of synthesized sketches, a cascaded regression strategy is adopted. Compared with the state-of-the-art face sketch synthesis methods, experimental results on several commonly used face sketch databases and celebrity photos demonstrate the effectiveness of the proposed method. PMID:26595919

  4. Methanol synthesis beyond chemical equilibrium

    NARCIS (Netherlands)

    van Bennekom, J. G.; Venderbosch, R. H.; Winkelman, J. G. M.; Wilbers, E.; Assink, D.; Lemmens, K. P. J.; Heeres, H. J.

    2013-01-01

    In commercial methanol production from syngas, the conversion is thermodynamically limited to 0.3-0.7 leading to large recycles of non-converted syngas. This problem can be overcome to a significant extent by in situ condensation of methanol during its synthesis which is possible nowadays due to the

  5. Sulfur monochloride in organic synthesis

    International Nuclear Information System (INIS)

    The data on the reactivity of sulfur monochloride published in the past 15 years have been reviewed and systematized. The review focuses on the synthesis of acyclic and heterocyclic compounds with the use of S2Cl2. The bibliography includes 154 references

  6. Biochemical synthesis with stable isotopes

    International Nuclear Information System (INIS)

    Descriptions of the biochemical synthesis of glucose-13C6 from Agmenellum quadruplication; the biochemical labelling of [13C, 15N] Chlorella and [13C] E. coli, [15N] E. coli, and the production of lactic-13C3 acid utilizing Lactobacillus casei are discussed

  7. Green chemistry for chemical synthesis

    Science.gov (United States)

    Li, Chao-Jun; Trost, Barry M.

    2008-01-01

    Green chemistry for chemical synthesis addresses our future challenges in working with chemical processes and products by inventing novel reactions that can maximize the desired products and minimize by-products, designing new synthetic schemes and apparati that can simplify operations in chemical productions, and seeking greener solvents that are inherently environmentally and ecologically benign. PMID:18768813

  8. Homeobox genes and melatonin synthesis

    DEFF Research Database (Denmark)

    Rohde, Kristian; Møller, Morten; Rath, Martin Fredensborg

    2014-01-01

    Nocturnal synthesis of melatonin in the pineal gland is controlled by a circadian rhythm in arylalkylamine N-acetyltransferase (AANAT) enzyme activity. In the rodent, Aanat gene expression displays a marked circadian rhythm; release of norepinephrine in the gland at night causes a cAMP-based indu...

  9. CAPTURED End Evaluation Synthesis Report

    NARCIS (Netherlands)

    Brouwers, J.H.A.M.

    2012-01-01

    This report provides the findings of the Synthesis Study of the CAPTURED Evaluation and is produced as part of the overall CAPTURED End Evaluation. After five years of support by the CAPTURED project the three CAPTURED partners have achieved commendable results. Ten lessons learned are formulated th

  10. Green chemistry for chemical synthesis

    OpenAIRE

    Li, Chao-Jun; Trost, Barry M.

    2008-01-01

    Green chemistry for chemical synthesis addresses our future challenges in working with chemical processes and products by inventing novel reactions that can maximize the desired products and minimize by-products, designing new synthetic schemes and apparati that can simplify operations in chemical productions, and seeking greener solvents that are inherently environmentally and ecologically benign.

  11. Insolubilized enzymes for food synthesis

    Science.gov (United States)

    Marshall, D. L.

    1972-01-01

    Cellulose matrix with numerous enzyme-coated silica particles of colloidal size permanently bound at various sites within matrix was produced that has high activity and possesses requisite physical characteristics for filtration or column operations. Product also allows coupling step in synthesis of edible food to proceed under mild conditions.

  12. Solventless synthesis of ruthenium nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    García-Peña, Nidia G. [Departmento de Tecnociencias, Universidad Nacional Autónoma de México, Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México, Cd. Universitaria A.P. 70-186, C.P. 04510 Coyoacán, México D.F. (Mexico); Redón, Rocío, E-mail: rredon@unam.mx [Departmento de Tecnociencias, Universidad Nacional Autónoma de México, Centro de Ciencias Aplicadas y Desarrollo Tecnológico, Universidad Nacional Autónoma de México, Cd. Universitaria A.P. 70-186, C.P. 04510 Coyoacán, México D.F. (Mexico); Herrera-Gomez, Alberto [Estudios Avanzados del Instituto Politécnico Nacional, Campus Juriquilla, Querétaro (Mexico); Fernández-Osorio, Ana Leticia [FES-Cuautitlán, Universidad Nacional Autónoma de México, Edo. de Mexico (Mexico); Bravo-Sanchez, Mariela; Gomez-Sosa, Gustavo [Estudios Avanzados del Instituto Politécnico Nacional, Campus Juriquilla, Querétaro (Mexico)

    2015-06-15

    Graphical abstract: - Highlights: • Successful synthesis of Ru nanoparticles by a cheap, fast and solventless approach was achieved. • The zero-valent state as well as the by-product/impurity free of the mechanochemical obtained Ru nanoparticles was proven by XPS, TEM and XRD. • Compared to two other synthesis strategies, the above-mentioned synthesis was more suitable to obtain smaller particles with fewer impurities in shorter time. - Abstract: This paper presents a novel solventless method for the synthesis of zero-valent ruthenium nanoparticles Ru(0). The proposed method, although not entirely new in the nanomaterials world, was used for the first time to synthesize zero-valent ruthenium nanoparticles. This new approach has proved to be an environmentally friendly, clean, cheap, fast, and reproducible technique which employs low amounts of solvent. It was optimized through varying amounts of reducing salt on a determined quantity of precursor and measuring the effect of this variation on the average particle size obtained. The resulting products were fully characterized by powder XRD, TEM, HR-TEM, and XPS studies, all of which corroborated the purity of the nanoparticles achieved. In order to verify the advantages of our method over other techniques, we compared our nanoparticles with two common colloidal-synthesized ruthenium nanoparticles.

  13. SOLID PHASE SYNTHESIS OF ISOXAZOLINES

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The solid-phase synthesis of isoxazolines on 2-polystyrylsulfonamidoethanol resin isreported. 2-Polystyrylsuifonamidoethanol resin 1 was reacted with acryloyl chloride to afford2-polystyrylsulfonylamidoethyl acrylate resin 2, which was further reacted with brominatedaldoximes by [3+2] cycioaddition to give isoxazoline resin 4. Resin 4 was treated with aqueous 6mol/L HCI solution to obtain isoxazolines in good yield and purity.

  14. Microwave synthesis of zirconia nanoparticles.

    Science.gov (United States)

    Hembram, K P S S; Rao, G Mohan

    2008-08-01

    Zirconia nanoparticles were prepared by microwave synthesis from zirconium acetate hydroxide. The samples were characterized by various techniques like X-ray diffraction (XRD), Scanning Electron microscopy (SEM), Transmission Electron microscopy (TEM), Raman Spectroscopy (RS). By XRD the average crystallite size is obtained around 10 nm and which is comparable to observation by SEM and TEM. PMID:19049194

  15. Solid-phase peptide synthesis

    DEFF Research Database (Denmark)

    Jensen, Knud Jørgen

    2013-01-01

    This chapter provides an introduction to and overview of peptide chemistry with a focus on solid-phase peptide synthesis. The background, the most common reagents, and some mechanisms are presented. This chapter also points to the different chapters and puts them into perspective....

  16. Catalysis and prebiotic RNA synthesis

    Science.gov (United States)

    Ferris, James P.

    1993-01-01

    The essential role of catalysis for the origins of life is discussed. The status of the prebiotic synthesis of 2',5'- and 3'5'-linked oligomers of RNA is reviewed. Examples of the role of metal ion and mineral catalysis in RNA oligomer formation are discussed.

  17. Synthesis of [{sup 75}Se]5-ethoxycarbonyl-4-methyl-1,2,3-selenadiazole

    Energy Technology Data Exchange (ETDEWEB)

    Jalilian, A.R. E-mail: amirreza.jalilian@yale.edu; Rowshanfarzad, P.; Afarideh, H.; Shafiee, A.; Sabet, M.; Kyoumarsi, M.; Raisali, Gh.R

    2004-05-01

    Selenium-75 (t{sub 1/2}=120.4 d; 100% EC) was prepared in no-carrier-added form by 22 MeV proton-bombardment of natural arsenic(III) oxide powder held in a copper-aluminum drawer target (highest yield, 35 {mu}Ci/{mu}Ah; maximum current, 6 {mu}A), followed by oxidation to [{sup 75}Se]selenium(IV) oxide. No-carrier-added [{sup 75}Se]5-ethoxycarbonyl-4-methyl-1,2,3-selenadiazole was prepared in one step from ethylacetoacetate semicarbazone with [{sup 75}Se]selenium(IV) oxide in glacial acetic acid at 50 deg. C. Column chromatography of the final solution afforded the desired labeled compound in 30% yield and greater than 98% radiochemical purity.

  18. Synthesis of single phase magnetite, Fe3O4 nanocrystallites using single source precursor

    Science.gov (United States)

    Disale, Sujit D.; Garje, Shivram S.

    2010-10-01

    Nanocrystalline Fe3O4 have been prepared using Fe(benzsczH)2Cl2 (where, benzsczH = benzaldehyde semicarbazone) as a single-source precursor. Fe(benzsczH)2Cl2 was characterized by elemental analyses, molar conductivity measearments, magnetic susceptibility studies, cyclic voltammetry and IR spectroscopy. The pyrolysis and solvothermal decomposition in ethylene glycol of this complex resulted in cubic phase Fe3O4 nanocrystals. These nanocrystals were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive analysis by X-rays, IR spectroscopy and hysteresis loop. XRD shows formation of cubic phase Fe3O4 for nanocrystallites obtained by both the methods. The TEM of nanoparticles obtained by pyrolysis show cubic shape plate-like morphology with average grain size of 54 nm and the nanoparticles obtained from solvothermal decomposition route have spherical shape morphology with average grain size of 16 nm.

  19. Stereoselective Synthesis of Amino Alcohols : Applications to Natural Product Synthesis

    OpenAIRE

    Torssell, Staffan

    2007-01-01

    This thesis is divided into four separate parts with amino alcohols as the common feature. The first part of the thesis describes the development of an efficient three-component approach to the synthesis of α-hydroxy-β-amino esters. Utilizing a highly diastereoselective Rh(II)-catalyzed 1,3-dipolar cycloaddition of carbonyl ylides to various aldimines, syn-α-hydroxy-β-amino esters are formed in high yields and excellent diastereoselectivities. An asymmetric version was also developed by emplo...

  20. The Total Synthesis of 14-Deoxycrassin and Pseudoplexaurol: A Convergent Synthesis of Cyclization Precursor

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The synthesis of epoxy aldehyde 4, a cyclization precursor for the total synthesis of 14-deoxycrassin and pseudoplexaurol, starting from geraniol in a convergent and stereoselective manner, is described.

  1. Flow "Fine" Synthesis: High Yielding and Selective Organic Synthesis by Flow Methods.

    Science.gov (United States)

    Kobayashi, Shū

    2016-02-18

    The concept of flow "fine" synthesis, that is, high yielding and selective organic synthesis by flow methods, is described. Some examples of flow "fine" synthesis of natural products and APIs are discussed. Flow methods have several advantages over batch methods in terms of environmental compatibility, efficiency, and safety. However, synthesis by flow methods is more difficult than synthesis by batch methods. Indeed, it has been considered that synthesis by flow methods can be applicable for the production of simple gasses but that it is difficult to apply to the synthesis of complex molecules such as natural products and APIs. Therefore, organic synthesis of such complex molecules has been conducted by batch methods. On the other hand, syntheses and reactions that attain high yields and high selectivities by flow methods are increasingly reported. Flow methods are leading candidates for the next generation of manufacturing methods that can mitigate environmental concerns toward sustainable society.

  2. Flow "Fine" Synthesis: High Yielding and Selective Organic Synthesis by Flow Methods.

    Science.gov (United States)

    Kobayashi, Shū

    2016-02-18

    The concept of flow "fine" synthesis, that is, high yielding and selective organic synthesis by flow methods, is described. Some examples of flow "fine" synthesis of natural products and APIs are discussed. Flow methods have several advantages over batch methods in terms of environmental compatibility, efficiency, and safety. However, synthesis by flow methods is more difficult than synthesis by batch methods. Indeed, it has been considered that synthesis by flow methods can be applicable for the production of simple gasses but that it is difficult to apply to the synthesis of complex molecules such as natural products and APIs. Therefore, organic synthesis of such complex molecules has been conducted by batch methods. On the other hand, syntheses and reactions that attain high yields and high selectivities by flow methods are increasingly reported. Flow methods are leading candidates for the next generation of manufacturing methods that can mitigate environmental concerns toward sustainable society. PMID:26337828

  3. Physical synthesis of quantum circuits using templates

    Science.gov (United States)

    Mirkhani, Zahra; Mohammadzadeh, Naser

    2016-06-01

    Similar to traditional CMOS circuits, quantum circuit design flow is divided into two main processes: logic synthesis and physical design. Addressing the limitations imposed on optimization of the quantum circuit metrics because of no information sharing between logic synthesis and physical design processes, the concept of "physical synthesis" was introduced for quantum circuit flow, and a few techniques were proposed for it. Following that concept, in this paper a new approach for physical synthesis inspired by template matching idea in quantum logic synthesis is proposed to improve the latency of quantum circuits. Experiments show that by using template matching as a physical synthesis approach, the latency of quantum circuits can be improved by more than 23.55 % on average.

  4. Physical synthesis of quantum circuits using templates

    Science.gov (United States)

    Mirkhani, Zahra; Mohammadzadeh, Naser

    2016-10-01

    Similar to traditional CMOS circuits, quantum circuit design flow is divided into two main processes: logic synthesis and physical design. Addressing the limitations imposed on optimization of the quantum circuit metrics because of no information sharing between logic synthesis and physical design processes, the concept of " physical synthesis" was introduced for quantum circuit flow, and a few techniques were proposed for it. Following that concept, in this paper a new approach for physical synthesis inspired by template matching idea in quantum logic synthesis is proposed to improve the latency of quantum circuits. Experiments show that by using template matching as a physical synthesis approach, the latency of quantum circuits can be improved by more than 23.55 % on average.

  5. Ethyl diazoacetate synthesis in flow

    Directory of Open Access Journals (Sweden)

    Mariëlle M. E. Delville

    2013-09-01

    Full Text Available Ethyl diazoacetate is a versatile compound in organic chemistry and frequently used on lab scale. Its highly explosive nature, however, severely limits its use in industrial processes. The in-line coupling of microreactor synthesis and separation technology enables the synthesis of this compound in an inherently safe manner, thereby making it available on demand in sufficient quantities. Ethyl diazoacetate was prepared in a biphasic mixture comprising an aqueous solution of glycine ethyl ester, sodium nitrite and dichloromethane. Optimization of the reaction was focused on decreasing the residence time with the smallest amount of sodium nitrite possible. With these boundary conditions, a production yield of 20 g EDA day−1 was achieved using a microreactor with an internal volume of 100 μL. Straightforward scale-up or scale-out of microreactor technology renders this method viable for industrial application.

  6. Mechanism Studies of LCP Synthesis

    Directory of Open Access Journals (Sweden)

    Anne Buyle Padias

    2011-05-01

    Full Text Available The LCP (Liquid Crystal Polymer known as Vectra is synthesized by acidolysis of 4-hydroxybenzoic acid with 6-hydroxy-2-naphthoic acid. The apparently simple acidolysis mechanism for LCP polycondensation is in fact a complex blend of mechanisms. Kinetics of model reactions and of actual polycondensations followed second-order kinetics and their rate constants were comparable. In the latter stages, ketene loss leads to phenolic ends, while decarboxylation provides phenyl ester ends. Accordingly, the mechanism changes to phenolysis. A quinone methide intermediate may also intervene, as revealed by kinetics studies and MALDI-TOF spectroscopy. Tailor-made matrices and synthesis of alternating well-defined oligomers assisted our studies. Nucleophilic aromatic substitutions may play a role, and we speculate on possible chain polycondensation. Esterolysis may be a useful alternative to LCP synthesis. Complications caused by ketene loss can be averted by the use of methoxycarbonyloxy monomers.

  7. Polyurethane synthesis reactions in asphalts

    Energy Technology Data Exchange (ETDEWEB)

    Bukowski, A.; Gretkiewicz, J.

    1982-04-01

    A series of asphalt-polyurethane composites was prepared by means of polyurethane synthesis in asphalt and carried out in melt. The applied materials were asphalts of differentiated group components content, polyester polyols of chain structure from linear to strongly branched, 2,4-tolylene diisocyanate, 4,4-methylenebis(phenyl isocyanate), and tinorganic catalyst. The asphalt components react with isocyanates to a minimal degree. The influence of the applied substrates, temperature, and polyurethane content in the system on the basic kinetic relations characterizing the process is presented. Polyurethane synthesis in asphalts does not differ in a fundamental way from the obtaining of polyurethanes, especially when their content in the composition is significant, 20 wt% and more.

  8. Synthesis of Polycyclic Natural Products

    Energy Technology Data Exchange (ETDEWEB)

    Tuan Hoang Nguyen

    2003-05-31

    With the continuous advancements in molecular biology and modern medicine, organic synthesis has become vital to the support and extension of those discoveries. The isolations of new natural products allow for the understanding of their biological activities and therapeutic value. Organic synthesis is employed to aid in the determination of the relationship between structure and function of these natural products. The development of synthetic methodologies in the course of total syntheses is imperative for the expansion of this highly interdisciplinary field of science. In addition to the practical applications of total syntheses, the structural complexity of natural products represents a worthwhile challenge in itself. The pursuit of concise and efficient syntheses of complex molecules is both gratifying and enjoyable.

  9. Hydrothermal Synthesis of Metal Silicates

    Institute of Scientific and Technical Information of China (English)

    Lii Kwang-Hwa

    2004-01-01

    Organically templated metal phosphates have been extensively studied because of interesting structural chemistry and potential applications in catalysis. However, in most cases the organic templates cannot be removed without collapse of the frameworks. This is in contrast to the high thermal stability and extensive applications of zeolites in refinery and petrochemical processes.Therefore, studies have been directed to the synthesis of transition metal silicates to produce more stable frameworks. Our synthetic methods are twofold, namely mild hydrothermal reactions in Teflon-lined autoclaves at 100-200 ℃ using organic amines as templates and high-temperature,high-pressure hydrothermal reactions in gold ampoules contained in a high-pressure reaction vessel at ca. 550 ℃ and 150 Mpa using alkali metal cations as templates. In this presentation I will report the high-temperature, high-pressure hydrothermal synthesis, crystal structures, and solid-state NMR spectroscopy of a number of new silicates of indium, uranium, and transition metals.

  10. Stereoselective Total Synthesis of (-)-Renieramycin T.

    Science.gov (United States)

    Yokoya, Masashi; Toyoshima, Ryoko; Suzuki, Toshihiro; Le, Vy H; Williams, Robert M; Saito, Naoki

    2016-05-20

    A stereoselective total synthesis of (-)-Renieramycin T (1t) from a key tetrahydroisoquinoline intermediate previously utilized in our formal total synthesis of Ecteinascidin 743 is described. The synthesis features a concise approach for construction of the pentacyclic framework using a Pictet-Spengler cyclization of bromo-substituted carbinolamine 17, which obviates the regioselectivity problem of the Pictet-Spengler cyclization. The results of cytotoxicity studies are also presented. PMID:27019081

  11. Small Molecule Library Synthesis Using Segmented Flow

    OpenAIRE

    Thompson, Christina M.; Djuric, Stevan W.; Cross, Jeffrey L.; Irini Akritopoulou-Zanze; Poole, Jennifer L.

    2011-01-01

    Flow chemistry has gained considerable recognition as a simple, efficient, and safe technology for the synthesis of many types of organic and inorganic molecules ranging in scope from large complex natural products to silicon nanoparticles. In this paper we describe a method that adapts flow chemistry to the synthesis of libraries of compounds using a fluorous immiscible solvent as a spacer between reactions. The methodology was validated in the synthesis of two small heterocycle containing l...

  12. Urea synthesis in patients with chronic pancreatitis

    DEFF Research Database (Denmark)

    Hamberg, Ole; Sonne, J; Larsen, S;

    2001-01-01

    Up-regulation of urea synthesis by amino acids and dietary protein intake may be impaired in patients with chronic pancreatitis (CP) due to the reduced glucagon secretion. Conversely, urea synthesis may be increased as a result of the chronic inflammation. The aims of the study were to determine...... urea synthesis kinetics in CP patients in relation to glucagon secretion (study I) and during an increase in protein intake (study II)....

  13. Novel algorithms for in vitro gene synthesis

    OpenAIRE

    Thachuk, Chris

    2007-01-01

    Methods for reliable synthesis of long genes offer great promise for novel protein synthesis via expression of synthetic genes. Current technologies use computational methods for design of short oligos, which can then be reliably synthesized and assembled into the desired target gene. A precursor to this process is optimization of the gene sequence for improved protein expression. In this thesis, we provide the first results on the computational complexity of oligo design for gene synthesis. ...

  14. Nanoparticle synthesis for magnetic hyperthermia

    OpenAIRE

    Thomas, L

    2010-01-01

    This work reports on an investigation into the synthesis, control, and stabilisation of iron oxide nanoparticles for biomedical applications using magnetic hyperthermia. A new understanding of the factors effecting nanoparticle growth in a coprecipitation methodology has been determined. This thesis challenges the highly cited Ostwald Ripening as the primary mechanism for nanoparticulate growth, and instead argues that in certain conditions, such as increasing reaction tempe...

  15. Substructuring and Component Mode Synthesis

    Directory of Open Access Journals (Sweden)

    P. Seshu

    1997-01-01

    Full Text Available Substructuring and component mode synthesis (CMS, is a very popular method of model reduction for large structural dynamics problems. Starting from the pioneering works on this technique in the early 1960s, many researchers have studied and used this technique in a variety of applications. Besides model reduction, CMS offers several other crucial advantages. The present work aims to provide a review of the available literature on this important technique.

  16. Substructuring and Component Mode Synthesis

    OpenAIRE

    Seshu, P.

    1997-01-01

    Substructuring and component mode synthesis (CMS), is a very popular method of model reduction for large structural dynamics problems. Starting from the pioneering works on this technique in the early 1960s, many researchers have studied and used this technique in a variety of applications. Besides model reduction, CMS offers several other crucial advantages. The present work aims to provide a review of the available literature on this important technique.

  17. Isotopologues Synthesis for KIE Studies

    OpenAIRE

    Sayre, Matthew

    2013-01-01

    The utilization of isotopic labeling is still growing in its use among chemists; the use of hydrogen isotope labeling allows for direct comparisons between two molecules undergoing a catalyzed reaction. An understanding of how the molecules behave when undergoing catalysis can be used when designing medication. Thus the understanding and prediction of chemical behavior at the molecular level can lead to a number of scientific advances; such as catalyst synthesis, inferences in biochemical rea...

  18. Artificial Intelligence A New Synthesis

    CERN Document Server

    Nilsson, Nils J

    1998-01-01

    Intelligent agents are employed as the central characters in this new introductory text. Beginning with elementary reactive agents, Nilsson gradually increases their cognitive horsepower to illustrate the most important and lasting ideas in AI. Neural networks, genetic programming, computer vision, heuristic search, knowledge representation and reasoning, Bayes networks, planning, and language understanding are each revealed through the growing capabilities of these agents. The book provides a refreshing and motivating new synthesis of the field by one of AI's master expositors and leading re

  19. SOLID PHASE SYNTHESIS OF ISOXAZOLINES

    Institute of Scientific and Technical Information of China (English)

    SUNWeimin; LUOJuntao; 等

    2002-01-01

    The solid-phase synthesis of isoxazolines on 2-polystyrylsulfonamidoethanol resin is reported.2-Polystyrylsulfonamidoethanol resin 1 was reacted with acryloyl chloride to afford 2-polystyrylsulfonylamidoethyl acrylate resin 2,which was further reacted with brominated aldoximes by [3+2] cycloaddition to give isoxazoline resin 4.Resin 4 was treated with aqueous 6 mol/L HCl solution to obtain isoxazolines in good yield and purity.

  20. Population Synthesis for Mira Variables

    Institute of Scientific and Technical Information of China (English)

    Chun-Hua Zhu; Chao-Zheng Zha

    2005-01-01

    By means of a population synthesis code, we investigate the Mira variables. Their birth rate (over 0.65yr-1) and their number (~ 130000) in the Galaxy are estimated. For all possible Mira variables, ranges of their initial masses,pulsating periods, mass losses and lifetimes are given. We check our model with the observed Mira variables near the Sun and our results prove to be valid.

  1. Synthesis of thermit noncorrodible steels

    OpenAIRE

    Жигуц, Юрій Юрійович

    2013-01-01

    The present paper the basic solutions to the problem of obtaining cavitation-resistant steels examined the use of thermite steels, the benefits of combining thermite steels with metallotermic methods of getting is showed. The advantages of metallotermic synthesis methods include: autonomy of processes, independence of energy sources, simplicity of equipment, high-performance process and easy transition from experimental research to industrial production. The need to developed the technology o...

  2. Synthesis of perfluoroalkylether triazine elastomers

    Science.gov (United States)

    Rosser, R. W.; Korus, R. A.

    1980-01-01

    A method of perfluoroalkylether triazine elastomer synthesis is described. To form an elastomer, the resultant polymer is heated in a closed oven at slightly reduced pressures for 1-day periods at 100, 130 and 150 C. A high-molecular-weight perfluoroalkylether triazine elastomer is produced that exhibits thermal and oxidative stability. This material is potentially useful in applications such as high-temperature seals, 'O' rings, and wire enamels.

  3. Expressive Sound Synthesis for Animation

    OpenAIRE

    Picard-Limpens, Cécile

    2009-01-01

    The main objective of this thesis is to provide tools for an expressive and real-time synthesis of sounds resulting from physical interactions of various objects in a 3D virtual environment. Indeed, these sounds, such as collisions sounds or sounds from continuous interaction between surfaces, are difficult to create in a pre-production process since they are highly dynamic and vary drastically depending on the interaction and objects. To achieve this goal, two approaches are proposed; the fi...

  4. Synthesis of tritium labelled sparsomycin

    Energy Technology Data Exchange (ETDEWEB)

    Broek, L.A.G.M. van den (Katholieke Univ. Nijmegen (Netherlands)); Willemsen, K.C.M.W.; Schlachter, I.H.G.; Ottenheijm, H.C.J.; Kaspersen, F.M. (Organon International B.V., Oss (Netherlands). Scientific Development Group)

    1989-05-01

    The synthesis is described of tritiated sparsomycin (5), a broad-spectrum antitumor antibiotic, with high specific activity (31.4 Ci/mmol, 1/16 TBq/mmol). The radiolabel was introduced by reduction of the cysteine methyl ester 1 with lithium borotritide, [sup 3]H NMR analysis of the final product showed the concomitant formation of the mono-and ditritiated compound in a ratio of 2:1. (Author).

  5. Environment and hydroelectricity colloquium - Synthesis

    International Nuclear Information System (INIS)

    This document proposes a synthesis of a colloquium dedicated to the interactions between hydroelectric installations and the environment. The four sessions respectively addressed the impacts of hydroelectric installations on ecosystems and more particularly on pisciculture populations (strategies for migration restoration, development of fish-friendly turbines), the sedimentary management of hydroelectric installations, the implementation of the Water Framework European Directive (Austrian experience, biological assessment criteria), and examples of environmental integration of existing or projected installations

  6. Chemo-enzymatic peptide synthesis : bioprocess engineering aspects

    OpenAIRE

    Vossenberg, P.

    2012-01-01

      Peptides, in particular oligopeptides, play an important role in the fields of health care, nutrition and cosmetics. Chemical synthesis is currently the most mature technique for the synthesis of peptides that range in length from 5 to 80 amino acids. Chemical synthesis is, however, expected to be more and more combined with enzyme-catalyzed synthesis, resulting in chemo-enzymatic approaches towards peptide synthesis. The racemization that hampers chemical synthesis can be prevented by...

  7. New frontiers in design synthesis

    Science.gov (United States)

    Goldin, Daniel S.; Venneri, Samuel L.; Noor, Ahmed K.

    1999-09-01

    The Intelligent Synthesis Environment (ISE), which is one of the major strategic technologies under development at NASA centers and the University of Virginia, is described. One of the major objectives of ISE is to significantly enhance the rapid creation of innovative affordable products and missions. ISE uses a synergistic combination of leading-edge technologies, including high performance computing, high capacity communications and networking, human-centered computing, knowledge-based engineering, computational intelligence, virtual product development, and product information management. The environment will link scientists, design teams, manufacturers, suppliers, and consultants who participate in the mission synthesis as well as in the creation and operation of the aerospace system. It will radically advance the process by which complex science missions are synthesized, and high-tech engineering systems are designed, manufactured and operated. The five major components critical to ISE are human-centered computing, infrastructure for distributed collaboration, rapid synthesis and simulation tools, life cycle integration and validation, and cultural change in both the engineering and science creative process. The five components and their subelements are described. Related U.S. government programs are outlined and the future impact of ISE on engineering research and education is discussed.

  8. Plasmenylethanolamine synthesis in Leishmania major.

    Science.gov (United States)

    Pawlowic, Mattie C; Hsu, Fong-Fu; Moitra, Samrat; Biyani, Neha; Zhang, Kai

    2016-07-01

    Ethanolamine glycerophospholipids are ubiquitous cell membrane components. Trypanosomatid parasites of the genus Leishmania synthesize the majority of their ethanolamine glycerophospholipids as 1-O-alk-1'-enyl-2-acyl-sn-glycero-3-phosphoethanolamine or plasmenylethanolamine (PME) through the Kennedy pathway. PME is a subtype of ether phospholipids also known as ethanolamine plasmalogen whose functions are not well characterized. In this study, we investigated the role of PME synthesis in Leishmania major through the characterization of an ethanolamine phosphotransferase (EPT) mutant. EPT-null parasites are largely devoid of PME and fully viable in regular medium but fail to proliferate in the absence of fetal bovine serum. They exhibit significant abnormalities in the synthesis and localization of GPI-anchored surface molecules. EPT-null mutants also show attenuated virulence in BALB/c mice. Furthermore, in addition to PME synthesis, ethanolamine also contributes to the production of phosphatidylcholine, the most abundant class of lipids in Leishmania. Together, these findings suggest that ethanolamine production is likely required for Leishmania promastigotes to generate bulk phospholipids, to handle stress, and to control the expression of membrane bound virulence factors. PMID:27062077

  9. A Sustainable Multicomponent Pyrimidine Synthesis.

    Science.gov (United States)

    Deibl, Nicklas; Ament, Kevin; Kempe, Rhett

    2015-10-14

    Since alcohols are accessible from indigestible biomass (lignocellulose), the development of novel preferentially catalytic reactions in which alcohols are converted into important classes of fine chemicals is a central topic of sustainable synthesis. Multicomponent reactions are especially attractive in organic chemistry as they allow the synthesis of large libraries of diversely functionalized products in a short time when run in a combinatorial fashion. Herein, we report a novel, regioselective, iridium-catalyzed multicomponent synthesis of pyrimidines from amidines and up to three (different) alcohols. This reaction proceeds via a sequence of condensation and dehydrogenation steps which give rise to selective C-C and C-N bond formations. While the condensation steps deoxygenate the alcohol components, the dehydrogenations lead to aromatization. Two equiv of hydrogen and water are liberated in the course of the reactions. PN5P-Ir-pincer complexes, recently developed in our laboratory, catalyze this sustainable multicomponent process most efficiently. A total of 38 different pyrimidines were synthesized in isolated yields of up to 93%. Strong points of the new protocol are its regioselectivity and thus the immediate access to pyrimidines that are highly and unsymmetrically decorated with alkyl or aryl substituents. The combination of this novel protocol with established methods for converting alcohols to nitriles now allows to selectively assemble pyrimidines from four alcohol building blocks and 2 equiv of ammonia.

  10. A concise and stereoselective synthesis of squalamine.

    Science.gov (United States)

    Zhang, Dong-Hui; Cai, Feng; Zhou, Xiang-Dong; Zhou, Wei-Shan

    2003-09-01

    [reaction: see text] A short and highly stereoselective synthesis of the novel steroid squalamine (1) was accomplished in nine steps from easily available methyl chenodeoxylcholanate 2. Our synthesis featured improved dehydrogenation of 4 followed by conjugate reduction to construct the trans AB-ring system and efficient asymmetric isopropylation of aldehyde 6 to introduce the C-24R-hydroxyl group. PMID:12943401

  11. Synthesis and antimicrobial activity of squalamine analogue.

    Science.gov (United States)

    Kim, H S; Choi, B S; Kwon, K C; Lee, S O; Kwak, H J; Lee, C H

    2000-08-01

    Synthesis and antimicrobial activity of squalamine analogue 2 are reported. The synthesis of 2 was accomplished from bisnoralcohol 3. The spermidine moiety was introduced via reductive amination of an appropriately functionalized 3beta-aminosterol with spermidinyl aldehyde 17 utilizing sodium triacetoxyborohydride as the reducing agent. Compound 2 shows weaker antimicrobial activity than squalamine. PMID:11003150

  12. Total Synthesis of the Cyanolide A Aglycon

    OpenAIRE

    Gesinski, Michael R.; Rychnovsky, Scott D.

    2011-01-01

    The synthesis of the potent molluscicide, cyanolide A, has been achieved in 10 steps without the use of protecting groups. The synthesis features a key Sakurai macrocyclization/dimerization reaction that simultaneously forms both tetrahydropyran rings and the macrocycle of the natural product.

  13. Asymmetric Total Synthesis of (-)-Cladospolide B

    Institute of Scientific and Technical Information of China (English)

    WANG,Wen-Kuan; ZHANG,Ji-Yong; HE,Jin-Mei; TANG,Shi-Bing; WANG,Xiao-Lei; SHE,Xue-Gong; PAN,Xin-Fu

    2008-01-01

    An enantioselective total synthesis of (-)-cladospolide B was described.The key steps in this synthesis include (a) a Sharpless asymmetric dihydroxylation to elaborate syn diol at C-4 and C-5 positions;(b) a Mitsunobu esterification to reverse the configuration at C-11 from (S) to (R);and (c) a ring-closing metathesis to access the 12-membered macrocyclic ring.

  14. Advances in Synthesis of Mesostructured Aluminophosphates

    Institute of Scientific and Technical Information of China (English)

    Benjing Xu; Chenxi Zhao; Zifeng Yan

    2005-01-01

    More and more attention has been paid to the synthesis of mesostructured aluminophosphates for many years. A lot of valuable research results, including various synthetic approaches and structural materials, have been obtained. This paper reviews the progress in the synthesis of mesostructured aluminophosphates over the past few years, with the hope of revealing opportunities for future work.

  15. The total synthesis of cannabisin G

    Directory of Open Access Journals (Sweden)

    YAMU XIA

    2010-12-01

    Full Text Available A convenient method for the synthesis of lignanamide cannabisin G, starting from vanillin, was developed. The convergent synthesis was based on the Stobbe reaction as C–C bond-forming steps to give the skeleton of lignan, which was condensed with a derivative of tyramine to obtain synthetic cannabisin G for the first time.

  16. Automatic Synthesis of Robust and Optimal Controllers

    DEFF Research Database (Denmark)

    Cassez, Franck; Jessen, Jan Jacob; Larsen, Kim Guldstrand;

    2009-01-01

    In this paper, we show how to apply recent tools for the automatic synthesis of robust and near-optimal controllers for a real industrial case study. We show how to use three different classes of models and their supporting existing tools, Uppaal-TiGA for synthesis, phaver for verification, and S...

  17. Synthesis of melamine-glucose resin adhesive

    Institute of Scientific and Technical Information of China (English)

    CHEN; Shuanhu; ZHANG; Lei

    2005-01-01

    The synthesis of a novel melamine-glucose adhesive that is similar to urea-formaldehyde adhesive is reported in this paper. The conditions of synthesis, such as the initial pH, the quantity of catalyst, the temperature of reaction, the percentage of each reactant and the time of reaction, were optimized by using the orthogonal experimental method.

  18. Microwave Hydrothermal Synthesis PZT of Nanometer Crystal

    Institute of Scientific and Technical Information of China (English)

    Hongxing LIU; Hong DENG; Yan LI; Yanrong LI

    2004-01-01

    It was focused on the applications and developments of microwave hydrothermal synthesis piezoelectric ceramic powder. The microwave hydrothermal vessel was designed and manufactured. The microwave hydrothermal synthesis system was established and the PZT piezoelectric ceramic powder was synthesized. XRD and TEM have been used to characterize the products in detail. The diameter of the PZT powder particle is from 40 to 60 nm.

  19. Upgrading protein synthesis for synthetic biology

    OpenAIRE

    O’Donoghue, Patrick; Ling, Jiqiang; Wang, Yane-Shih; Söll, Dieter

    2013-01-01

    Genetic code expansion for synthesis of proteins containing noncanonical amino acids is a rapidly growing field in synthetic biology. Creating optimal orthogonal translation systems will require re-engineering central components of the protein synthesis machinery on the basis of a solid mechanistic biochemical understanding of the synthetic process.

  20. Lactobacillus assisted synthesis of titanium nanoparticles

    Science.gov (United States)

    Prasad, K.; Jha, Anal K.; Kulkarni, A. R.

    2007-05-01

    An eco-friendly lactobacillus sp. (microbe) assisted synthesis of titanium nanoparticles is reported. The synthesis is performed at room temperature. X-ray and transmission electron microscopy analyses are performed to ascertain the formation of Ti nanoparticles. Individual nanoparticles as well as a number of aggregates almost spherical in shape having a size of 40 60 nm are found.

  1. A modified total synthesis of cystothiazole A

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A modified total synthesis of cystothiazole A is described. In this synthetic strategy, a one-step transformation of acylated oxazolidinone to β-ketoester has been successfully applied, thus making the synthetic route more efficient. This method may also be potentially applied in synthesis of other related β-substituted-β-methoxyl acrylates (bb-MOAs).

  2. SCMC for SLA: A Research Synthesis

    Science.gov (United States)

    Sauro, Shannon

    2011-01-01

    This research synthesis explores the role of synchronous computer-mediated communication (SCMC) for second language acquisition (SLA). Using Hymes' (1971) notion of communicative competence and Canale and Swain's (1980; Canale, 1983) subsequent framework for communicative language teaching, the synthesis examines the research trends, methods, and…

  3. Total Synthesis of (±)-Celaphanol A

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The first total synthesis of (±)-Celaphanol A was accomplished starting from α-cyclocitral and 3,4-dimethoxy benzyl chloride via a six-step process, in which the intramolecular cyclization of ketone 4 with BF3@Et2O afforded an all-cis isomer intermediate for synthesis of aromatic tricyclic diterpenes.

  4. The methods of synthesis of glycerin derivatives

    International Nuclear Information System (INIS)

    In this chapter of book authors present some methods of synthesis of glycerin derivatives, in particular, synthesis of 3-met oxi-1.2-propandiol, 1.3-di-benzil-oxi-2-propanol, 1-ge xi-lox-3-chlorine-2-propanol and other

  5. Accelerate synthesis in ecology and environmental sciences

    Science.gov (United States)

    Synthesis of diverse knowledge is a central part of all sciences, but especially those such as ecology and environmental sciences which draw information from many disciplines. Research and education in ecology are intrinsically synthetic, and synthesis is increasingly needed to find solutions for en...

  6. Standardized chemical synthesis of Pseudomonas aeruginosa pyocyanin

    Directory of Open Access Journals (Sweden)

    Rajkumar Cheluvappa

    2014-01-01

    As we have extracted pyocyanin both from P. aeruginosa cultures, and via chemical synthesis; we know the procedural and product-quality differences. We endorse the relative ease, safety, and convenience of using the chemical synthesis described here. Crucially, our “naturally endotoxin-free” pyocyanin can be extracted easily without using infectious bacteria.

  7. Catalytic asymmetric synthesis of mycocerosic acid

    NARCIS (Netherlands)

    ter Horst, B.; Feringa, B.L.; J. Minnaard, A.

    2007-01-01

    The first catalytic asymmetric total synthesis of mycocerosic acid was achieved via the application of iterative enantioselective 1,4-addition reactions and allows for the efficient construction of 1,3-polymethyl arrays with full stereocontrol; further exemplified by the synthesis of tetramethyl-dec

  8. Synthesis of a jojoba bean disaccharide.

    Science.gov (United States)

    Kornienko, A; Marnera, G; d'Alarcao, M

    1998-08-01

    A synthesis of the disaccharide recently isolated from jojoba beans, 2-O-alpha-D-galactopyranosyl-D-chiro-inositol, has been achieved. The suitably protected chiro-inositol unit was prepared by an enantiospecific synthesis from L-xylose utilizing SmI2-mediated pinacol coupling as a key step.

  9. Astrobiology - The New Synthesis

    Science.gov (United States)

    Sik, A.; Simon, T.

    á vált sötétebb helyekre való költöztetése: mélyen a föld alá helyezik, a forró vulkáni kőzetek hasadékaiba, ahol bőségesen találhatott magának ként, vasat, hidrogént és szenet. A genetikai bizonyítékok alapján a hő- és mélységkedvelők es- 4 nek legközelebb az egyetemes őshöz. [16]. The synthesis Mindezek alapján a földi extremofilek vizsgálata során deríthetjük ki, hogy más égitesteken (egyelőre a Naprendszerben) hol kell keresnünk az életet, és mit kell keresnünk a planetológiai kutatások során egyre jobban megismert szélsőséges környezetekben. Segítségükkel megtudhatjuk, melyek azok az alak- tani, geokémiai, esetleg biokémiai jegyek, amelyek életre utalhatnak; melyek az élet azon alapvető jellemzői, amelyek elég általánosak és biztonsággal kimu- tathatók, milyen műszerekkel kell felszerelnünk a jövő űrszondáit, milyen módszereket kell alkalmaznunk, hogy sikerrel kutathassunk a Földön kívüli élet után. References [1] H. Hargitai et. al., XXXIII. LPSC (2002), Houston, #1261; [2] Origins Roadmap, 2000, JPL; [3] http://www.obspm.fr/encycl/catalog.html [4] http://www.physics.sfsu.edu/~gmarcy/planetsearch/ upsand/upsand.html [5] http://tpf.jpl.nasa.gov/ [6] A. Kereszturi, and A. Sik, XXXI. LPSC (2000), Houston, #1216; [7] S. W. Squyres et. al. (1992) in H. H. Kieffer, et. al.: Mars, University of Arizona Press, Tucson, 523-554; [8] http://www.jpl.nasa.gov/europaorbiter/ [9] www.nineplanets.org [10] http://www.jpl.nasa.gov/cassini/ [11] http://www- curator.jsc.nasa.gov/curator/antmet/ marsmets/alh84001/sample.htm [12] P. Davies: The fifth miracle - The search for the origin of life (1998), Orion; [13] M. T. Madigan and B. L. Marrs: Extremophiles, Scientific American (1997), 276, 82-87; [14] J. A. Lake et al.: Methanococcus Genome, Science (1996), 274, 901-905; [15] N. C. Kyrpides and G. J. Olsen: Archaeal and bacterial hyperthermophiles: Horizontal gene exchange or common ancestry?, Trends in

  10. Hydrothermal synthesis of sodium titanate nanotubes

    International Nuclear Information System (INIS)

    From suspension of nanoparticles TiO2 in concentrated water solution of NaOH were prepared by hydrothermal synthesis sodium titanates particles with different shapes. Influence of synthesis duration under temperature 180 grad C on the change of particles shapes was observed. The result of experiment showed that one day synthesis resulted to obtained product with high content of nanotubes, but the extension of this period led to the transformation of product's shape into stripes. From the results of experiment follows that as a precursor for TiO2 nanotubes preparation may be used only products of hydrothermal synthesis, which duration of pressure synthesis was not longer than 24 hours. (authors)

  11. Small Molecule Library Synthesis Using Segmented Flow

    Directory of Open Access Journals (Sweden)

    Christina M. Thompson

    2011-11-01

    Full Text Available Flow chemistry has gained considerable recognition as a simple, efficient, and safe technology for the synthesis of many types of organic and inorganic molecules ranging in scope from large complex natural products to silicon nanoparticles. In this paper we describe a method that adapts flow chemistry to the synthesis of libraries of compounds using a fluorous immiscible solvent as a spacer between reactions. The methodology was validated in the synthesis of two small heterocycle containing libraries. The reactions were performed on a 0.2 mmol scale, enabling tens of milligrams of material to be generated in a single 200 mL reaction plug. The methodology allowed library synthesis in half the time of conventional microwave synthesis while maintaining similar yields. The ability to perform multiple, potentially unrelated reactions in a single run is ideal for making small quantities of many different compounds quickly and efficiently.

  12. Depth-optimized reversible circuit synthesis

    Science.gov (United States)

    Arabzadeh, Mona; Saheb Zamani, Morteza; Sedighi, Mehdi; Saeedi, Mehdi

    2013-04-01

    In this paper, simultaneous reduction of circuit depth and synthesis cost of reversible circuits in quantum technologies with limited interaction is addressed. We developed a cycle-based synthesis algorithm which uses negative controls and limited distance between gate lines. To improve circuit depth, a new parallel structure is introduced in which before synthesis a set of disjoint cycles are extracted from the input specification and distributed into some subsets. The cycles of each subset are synthesized independently on different sets of ancillae. Accordingly, each disjoint set can be synthesized by different synthesis methods. Our analysis shows that the best worst-case synthesis cost of reversible circuits in the linear nearest neighbor architecture is improved by the proposed approach. Our experimental results reveal the effectiveness of the proposed approach to reduce cost and circuit depth for several benchmarks.

  13. Feature-aware natural texture synthesis

    KAUST Repository

    Wu, Fuzhang

    2014-12-04

    This article presents a framework for natural texture synthesis and processing. This framework is motivated by the observation that given examples captured in natural scene, texture synthesis addresses a critical problem, namely, that synthesis quality can be affected adversely if the texture elements in an example display spatially varied patterns, such as perspective distortion, the composition of different sub-textures, and variations in global color pattern as a result of complex illumination. This issue is common in natural textures and is a fundamental challenge for previously developed methods. Thus, we address it from a feature point of view and propose a feature-aware approach to synthesize natural textures. The synthesis process is guided by a feature map that represents the visual characteristics of the input texture. Moreover, we present a novel adaptive initialization algorithm that can effectively avoid the repeat and verbatim copying artifacts. Our approach improves texture synthesis in many images that cannot be handled effectively with traditional technologies.

  14. Assessment of structural diversity in combinatorial synthesis.

    Science.gov (United States)

    Fergus, Suzanne; Bender, Andreas; Spring, David R

    2005-06-01

    This article covers the combinatorial synthesis of small molecules with maximal structural diversity to generate a collection of pure compounds that are attractive for lead generation in a phenotypic, high-throughput screening approach. Nature synthesises diverse small molecules, but there are disadvantages with using natural product sources. The efficient chemical synthesis of structural diversity (and complexity) is the aim of diversity-oriented synthesis, and recent progress is reviewed. Specific highlights include a discussion of strategies to obtain structural diversity and an analysis of molecular descriptors used to classify compounds. The assessment of how successful one synthesis is versus another is subjective, therefore we test-drive software to assess structural diversity in combinatorial synthesis, which is freely available via a web interface.

  15. Combustion synthesis of advanced composite materials

    Science.gov (United States)

    Moore, John J.

    1993-01-01

    Self-propagating high temperature (combustion) synthesis (SHS), has been investigated as a means of producing both dense and expanded (foamed) ceramic and ceramic-metal composites, ceramic powders and whiskers. Several model exothermic combustion synthesis reactions were used to establish the importance of certain reaction parameters, e.g., stoichiometry, green density, combustion mode, particle size, etc. on the control of the synthesis reaction, product morphology and properties. The use of an in situ liquid infiltration technique and the effect of varying the reactants and their stoichiometry to provide a range of reactant and product species i.e., solids, liquids and gases, with varying physical properties e.g., volatility and thermal conductivity, on the microstructure and morphology of synthesized composite materials is discussed. Conducting the combustion synthesis reaction in a reactive gas environment to take advantage of the synergistic effects of combustion synthesis and vapor phase transport is also examined.

  16. Synthesis document of the presentations

    International Nuclear Information System (INIS)

    This colloquium has been organized to answer questions from health professionals. They are more and more confronted to public information about public health and to patient anxiety. The aim of the interventions is to realize a clearly and comprehensive synthesis of events concerning the nuclear and health domain during 2000. The following three sessions deal with this subject: occupational diseases and ionizing radiation; the public information and attitude facing nuclear accidents and especially Chernobyl; medical and sanitary aspects of a nuclear accident: management and follow up of people. (A.L.B.)

  17. Ibuprofen: Synthesis, production and properties

    Directory of Open Access Journals (Sweden)

    Mijin Dušan Ž.

    2003-01-01

    Full Text Available Since its introduction in 1969, ibuprofen has become one of the most common painkillers in the world. Ibuprofen in an NSAID (non-steroidal anti-inflammatory drug and like other drugs of its class it possesses analgetic, antipyretic and anti-inflammatory properties. While ibuprofen is a relatively simple molecule, there is still sufficient structural complexity to ensure that a large number of different synthetic approaches are possible. Since the introduction of pharmaceutical products containing ibuprofen, industrial and academic scientists have developed many potential production processes. This paper describes the history, synthesis and production, as well as the properties and stability of ibuprofen.

  18. The total synthesis of (-)-nitidasin.

    Science.gov (United States)

    Hog, Daniel T; Huber, Florian M E; Mayer, Peter; Trauner, Dirk

    2014-08-01

    Nitidasin is a pentacyclic sesterterpenoid with a rare 5-8-6-5 carbon skeleton that was isolated from the Peruvian folk medicine "Hercampuri". It belongs to a small class of sesterterpenoids that feature an isopropyl trans-hydrindane moiety fused to a variety of other ring systems. As a first installment of our general approach toward these natural products, we report the total synthesis of the title compound. Our stereoselective, convergent route involves the addition of a complex alkenyl lithium compound to a trans-hydrindanone, followed by chemoselective epoxidation, ring-closing olefin metathesis, and redox adjustment.

  19. Synthesis of elusive chloropnictenium ions.

    Science.gov (United States)

    Hering-Junghans, Christian; Thomas, Max; Villinger, Alexander; Schulz, Axel

    2015-04-27

    This work describes the synthesis and full characterization of elusive chloropnictenium ion salts of the type [(R)Ar*N(SiMe)ECl][A] ((R)Ar* = 2,6-(CHPh2)-4-R-C6H2, R = Me, tBu; E = Sb, Bi; A(-) = GaCl4, Al(OCH(CF3)2)4). In these species the cation is significantly stabilized by weak arene interactions to flanking phenyl groups of the (R)Ar* moiety. In this context the bonding situation has been studied by computational means and the reactivity towards the Lewis base 4-dimethylaminopyridine (dmap) was investigated.

  20. Synthesis of chemically modified DNA.

    Science.gov (United States)

    Shivalingam, Arun; Brown, Tom

    2016-06-15

    Naturally occurring DNA is encoded by the four nucleobases adenine, cytosine, guanine and thymine. Yet minor chemical modifications to these bases, such as methylation, can significantly alter DNA function, and more drastic changes, such as replacement with unnatural base pairs, could expand its function. In order to realize the full potential of DNA in therapeutic and synthetic biology applications, our ability to 'write' long modified DNA in a controlled manner must be improved. This review highlights methods currently used for the synthesis of moderately long chemically modified nucleic acids (up to 1000 bp), their limitations and areas for future expansion. PMID:27284032

  1. fsclean: Faraday Synthesis CLEAN imager

    Science.gov (United States)

    Bell, M. R.; Ensslin, T. A.

    2015-06-01

    Fsclean produces 3D Faraday spectra using the Faraday synthesis method, transforming directly from multi-frequency visibility data to the Faraday depth-sky plane space. Deconvolution is accomplished using the CLEAN algorithm, and the package includes Clark and Högbom style CLEAN algorithms. Fsclean reads in MeasurementSet visibility data and produces HDF5 formatted images; it handles images and data of arbitrary size, using scratch HDF5 files as buffers for data that is not being immediately processed, and is limited only by available disk space.

  2. Stereoselective Total Synthesis of Mycalamides

    Institute of Scientific and Technical Information of China (English)

    Masahiro Toyota

    2005-01-01

    @@ 1Introduction Mycalamides A (1a) and B (1b) are potent antiviral compounds from a New Zealand sponge of the genus Mycale. Apart from their antitumor property, mycalamide A (1a) exhibits immunosuppressive action by blocking T-cell activation in mice and is significantly more potent than FK-506 and cyclosporine A. Because of their intriguing biological activity, unique structures and scarce supply of these natural products, mycalamides A (1a) and B (1b) have attracted considerable attention as target molecules for total synthesis, and total, formal, or partial syntheses of this family of compounds have been reported[1,2].

  3. Manganese borohydride; synthesis and characterization

    OpenAIRE

    Richter, Bo; Ravnsbæk, Dorthe B.; Tumanov, Nikolay; Filinchuk, Yaroslav; Jensen, Torben R.

    2015-01-01

    Solvent-based synthesis and characterization of α-Mn(BH4)2 and a new nanoporous polymorph of manganese borohydride, γ-Mn(BH4)2, via a new solvate precursor, Mn(BH4)2·1/2S(CH3)2, is presented. Manganese chloride is reacted with lithium borohydride in a toluene/dimethylsulfide mixture at room temperature, which yields halide and solvent-free manganese borohydride after extraction with dimethylsulfide (DMS) and subsequent removal of residual solvent. This work constitutes the first example of es...

  4. The synthesis paradigm in genetics.

    Science.gov (United States)

    Rice, William R

    2014-02-01

    Experimental genetics with model organisms and mathematically explicit genetic theory are generally considered to be the major paradigms by which progress in genetics is achieved. Here I argue that this view is incomplete and that pivotal advances in genetics--and other fields of biology--are also made by synthesizing disparate threads of extant information rather than generating new information from experiments or formal theory. Because of the explosive expansion of information in numerous "-omics" data banks, and the fragmentation of genetics into numerous subdisciplines, the importance of the synthesis paradigm will likely expand with time.

  5. Cellulose Synthesis in Agrobacterium tumefaciens

    Energy Technology Data Exchange (ETDEWEB)

    Alan R. White; Ann G. Matthysse

    2004-07-31

    We have cloned the celC gene and its homologue from E. coli, yhjM, in an expression vector and expressed the both genes in E. coli; we have determined that the YhjM protein is able to complement in vitro cellulose synthesis by extracts of A. tumefaciens celC mutants, we have purified the YhjM protein product and are currently examining its enzymatic activity; we have examined whole cell extracts of CelC and various other cellulose mutants and wild type bacteria for the presence of cellulose oligomers and cellulose; we have examined the ability of extracts of wild type and cellulose mutants including CelC to incorporate UDP-14C-glucose into cellulose and into water-soluble, ethanol-insoluble oligosaccharides; we have made mutants which synthesize greater amounts of cellulose than the wild type; and we have examined the role of cellulose in the formation of biofilms by A. tumefaciens. In addition we have examined the ability of a putative cellulose synthase gene from the tunicate Ciona savignyi to complement an A. tumefaciens celA mutant. The greatest difference between our knowledge of bacterial cellulose synthesis when we started this project and current knowledge is that in 1999 when we wrote the original grant very few bacteria were known to synthesize cellulose and genes involved in this synthesis were sequenced only from Acetobacter species, A. tumefaciens and Rhizobium leguminosarum. Currently many bacteria are known to synthesize cellulose and genes that may be involved have been sequenced from more than 10 species of bacteria. This additional information has raised the possibility of attempting to use genes from one bacterium to complement mutants in another bacterium. This will enable us to examine the question of which genes are responsible for the three dimensional structure of cellulose (since this differs among bacterial species) and also to examine the interactions between the various proteins required for cellulose synthesis. We have carried out one

  6. Automated synthesis of sialylated oligosaccharides

    Directory of Open Access Journals (Sweden)

    Davide Esposito

    2012-09-01

    Full Text Available Sialic acid-containing glycans play a major role in cell-surface interactions with external partners such as cells and viruses. Straightforward access to sialosides is required in order to study their biological functions on a molecular level. Here, automated oligosaccharide synthesis was used to facilitate the preparation of this class of biomolecules. Our strategy relies on novel sialyl α-(2→3 and α-(2→6 galactosyl imidates, which, used in combination with the automated platform, provided rapid access to a small library of conjugation-ready sialosides of biological relevance.

  7. EXOPOLYSACCHARIDES SYNTHESIS ON INDUSTRIAL WASTES

    Directory of Open Access Journals (Sweden)

    T.P.

    2016-04-01

    Full Text Available Data from the literature and our own studies on the synthesis of microbial exopolysaccharides on various industrial waste (food industry, agricultural sector, biodiesel production, etc. are reviewed here. Utilization of industrial waste to obtain exopolysaccharides will solve not only the problem of secondary raw materials accumulation, but also will reduce the costs of the biosynthesis of practically valuable metabolites. In addition, some kinds of waste have a number of advantages compared to traditional carbohydrate substrates: aside from environmental health benefits, there are technological ones, like the presence of growth factors. There is also no need to use anti-foam substances and substrate sterilization in the latter case.

  8. Synthesis of super heavy elements

    International Nuclear Information System (INIS)

    An era of study and synthesis of superheavy elements began with the prediction of the existence of an island of stability of long lived superheavy elements in the vicinity Z = 126, N = 184 by Myers and Swiatecki in 1966. Within coulomb and proximity potential model, we have studied cluster emission from all even-even nuclei from 270118 to 318118. Fission decay half lives for these isotopes are calculated by the model proposed by Ren et al. The range of isotopes in which α-decay shall occur for the element Z=118 is found out using the difference in α-decay half life and fission decay half life as a criterion. This range is also the one in which isotopes can exist without getting spontaneously fissioned. Making use of the concepts of quantum mechanical fragmentation theory and the information that is gathered from our work, about the range of isotopes where synthesis of Z = 118 is probable, sets of reactions, according to order of possibility, for the production of all isotopes in the range have been elucidated. Along with that the involved fusion barrier and ground state Q-value also are shown

  9. Fluxnet Synthesis Dataset Collaboration Infrastructure

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Deborah A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Humphrey, Marty [Univ. of Virginia, Charlottesville, VA (United States); van Ingen, Catharine [Microsoft. San Francisco, CA (United States); Beekwilder, Norm [Univ. of Virginia, Charlottesville, VA (United States); Goode, Monte [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Jackson, Keith [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Rodriguez, Matt [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Weber, Robin [Univ. of California, Berkeley, CA (United States)

    2008-02-06

    The Fluxnet synthesis dataset originally compiled for the La Thuile workshop contained approximately 600 site years. Since the workshop, several additional site years have been added and the dataset now contains over 920 site years from over 240 sites. A data refresh update is expected to increase those numbers in the next few months. The ancillary data describing the sites continues to evolve as well. There are on the order of 120 site contacts and 60proposals have been approved to use thedata. These proposals involve around 120 researchers. The size and complexity of the dataset and collaboration has led to a new approach to providing access to the data and collaboration support and the support team attended the workshop and worked closely with the attendees and the Fluxnet project office to define the requirements for the support infrastructure. As a result of this effort, a new website (http://www.fluxdata.org) has been created to provide access to the Fluxnet synthesis dataset. This new web site is based on a scientific data server which enables browsing of the data on-line, data download, and version tracking. We leverage database and data analysis tools such as OLAP data cubes and web reports to enable browser and Excel pivot table access to the data.

  10. Understanding Synthesis Across Disciplines to Improve Nursing Education.

    Science.gov (United States)

    Blondy, Laurie C; Blakeslee, Ann M; Scheffer, Barbara K; Rubenfeld, M Gaie; Cronin, Brenda M; Luster-Turner, Rose

    2016-06-01

    Nursing students must learn higher-order thinking skills of analysis and synthesis to manage complex data for decision making in healthcare. Teaching synthesis, however, is challenging and elusive due to lack of understanding of the concept and an explicit pedagogy for teaching it. A qualitative, multi-phased research project was designed to gain understanding of what synthesis is, how professionals acquire synthesis skills, and how to best teach synthesis. The first phase explored interdisciplinary descriptions of synthesis. Three focus groups were conducted, and interdisciplinary participants responded to several questions. Several themes emerged suggesting that synthesis depends on cognitive skills and competencies, situational and contextual factors, preparation and knowledge acquisition skills, interpersonal and interaction skills, and personal qualities. Participants also supported use of multi-modal teaching strategies to reinforce students' use of synthesis in learning. This project provided a beginning understanding of the synthesis process, revealing striking similarities in synthesis across professional disciplines. PMID:26689219

  11. Bioinspired synthesis of magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    David, Anand

    2009-05-26

    The synthesis of magnetic nanoparticles has long been an area of active research. Magnetic nanoparticles can be used in a wide variety of applications such as magnetic inks, magnetic memory devices, drug delivery, magnetic resonance imaging (MRI) contrast agents, and pathogen detection in foods. In applications such as MRI, particle uniformity is particularly crucial, as is the magnetic response of the particles. Uniform magnetic particles with good magnetic properties are therefore required. One particularly effective technique for synthesizing nanoparticles involves biomineralization, which is a naturally occurring process that can produce highly complex nanostructures. Also, the technique involves mild conditions (ambient temperature and close to neutral pH) that make this approach suitable for a wide variety of materials. The term 'bioinspired' is important because biomineralization research is inspired by the naturally occurring process, which occurs in certain microorganisms called 'magnetotactic bacteria'. Magnetotactic bacteria use biomineralization proteins to produce magnetite crystals having very good uniformity in size and morphology. The bacteria use these magnetic particles to navigate according to external magnetic fields. Because these bacteria synthesize high quality crystals, research has focused on imitating aspects of this biomineralization in vitro. In particular, a biomineralization iron-binding protein found in a certain species of magnetotactic bacteria, magnetospirillum magneticum, AMB-1, has been extracted and used for in vitro magnetite synthesis; Pluronic F127 gel was used to increase the viscosity of the reaction medium to better mimic the conditions in the bacteria. It was shown that the biomineralization protein mms6 was able to facilitate uniform magnetite synthesis. In addition, a similar biomineralization process using mms6 and a shorter version of this protein, C25, has been used to synthesize cobalt ferrite

  12. Bioinspired synthesis of magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    David, Anand [Iowa State Univ., Ames, IA (United States)

    2009-01-01

    The synthesis of magnetic nanoparticles has long been an area of active research. Magnetic nanoparticles can be used in a wide variety of applications such as magnetic inks, magnetic memory devices, drug delivery, magnetic resonance imaging (MRI) contrast agents, and pathogen detection in foods. In applications such as MRI, particle uniformity is particularly crucial, as is the magnetic response of the particles. Uniform magnetic particles with good magnetic properties are therefore required. One particularly effective technique for synthesizing nanoparticles involves biomineralization, which is a naturally occurring process that can produce highly complex nanostructures. Also, the technique involves mild conditions (ambient temperature and close to neutral pH) that make this approach suitable for a wide variety of materials. The term 'bioinspired' is important because biomineralization research is inspired by the naturally occurring process, which occurs in certain microorganisms called 'magnetotactic bacteria'. Magnetotactic bacteria use biomineralization proteins to produce magnetite crystals having very good uniformity in size and morphology. The bacteria use these magnetic particles to navigate according to external magnetic fields. Because these bacteria synthesize high quality crystals, research has focused on imitating aspects of this biomineralization in vitro. In particular, a biomineralization iron-binding protein found in a certain species of magnetotactic bacteria, magnetospirillum magneticum, AMB-1, has been extracted and used for in vitro magnetite synthesis; Pluronic F127 gel was used to increase the viscosity of the reaction medium to better mimic the conditions in the bacteria. It was shown that the biomineralization protein mms6 was able to facilitate uniform magnetite synthesis. In addition, a similar biomineralization process using mms6 and a shorter version of this protein, C25, has been used to synthesize cobalt ferrite

  13. Abiogenic synthesis on terrestrial orbit

    Science.gov (United States)

    Simakov, Michael B.; Kuzicheva, Evgenia; Gontareva, Natalia

    Meteorites probably played a central role in the evolution of life. Due to the structure, they tend to adsorb organic compounds and catalyze a variety of organic reactions critical to scenarios of life’s origins. We have shown experimentally that extraterrestrial minerals can catalyze the formation of peptides and nucleotides. The present study was performed onboard different Russian space stations (BION, COSMOS, and MIR) with various duration, altitude, and radiation conditions. Irradiation of solid samples, free or admixed with certain minerals, was the major task of future space flight experiments, planned for performing onboard Russian space satellite Bion-M. The «simulated space ice conditions» experiments have shown the synthesis of simple biochemical compounds in the form of amino acid’s precursors and pyrimidine bases (uracil, cyrosine and thymine) of the nucleic acids. Our investigation dealt with further reaction of nucleic acid components to nucleotides - main components of RNA and DNA, and single aminoacids to oligopeptides. We investigated two types of reactions: (1) abiogenic synthesis of nucleotides from mixtures of nucleoside + inorganic phosphate; (2) abiogenic synthesis of dipeptides from mixtures of simple amino acids. The reaction mixture in the form of a solid film contains (1) nucleoside and dihydrogen phosphate; (2) two different amino acids. Seven different nucleosides (thymidine, cytidine, uracil, adenosine or deoxyadenosine, guanosine or deoxyguanosine) and four mixtures of aromatic (tyrosine or triptophan) and aliphatic (glycine or alanine) amino acids were investigated. Mixtures were irradiated as solid films with different sources of energy: (1) VUV-light of 145 nm; (2) high energy protons (2-6 MeV); and (3) were installed on the surface of biosputnik in outstanding container when they were exposed to the action of all spectra of the open space energy sources during the entire time of flight. We have shown experimentally that the

  14. Synthesis of nano anatase for titanosilicate ETS-10 synthesis

    Science.gov (United States)

    Shafeque, Shihara

    Functionalized textiles present a vast and growing niche in the global textile market at US $400 billion [1, 2]. Engelhard Titanium Silicate 10 (ETS-10), a photocatalytic zeo-type material if coated on textiles, is expected to impart useful properties similar to TiO2, such as stain-resistant, odor repellant, bactericidal and enhanced UV protection [3, 4]. Typically, small ETS-10 crystals of size ˜300-800 nm are synthesized using solid titania (e.g., anatase or P25) sources [5, 6, 7]. However, smaller ETS-10 crystals are required for a uniform surface coating with highly effective surface area. The dissolution of titania particles (i.e., their size) is hypothesized to be important in small ETS-10 crystal formation [5, 6, 7]. Nano anatase was synthesized by modification of two methods: direct precipitation [7] and sol-gel synthesis [3]. Analysis by XRD confirmed that both methods produced nano anatase of crystallite size ˜4-5 nm. However, FE-SEM analysis showed that product from direct precipitation, existed as intergrown spheroidal particles with size ˜1.0 mum. These particles dispersed poorly in deionized water. Therefore, the best nano anatase samples were from sol-gel synthesis in two forms, dry powder and colloidal anatase. ETS-10 synthesis was investigated using two methods adopted from literature [6, 7]. The method of Yoon and co-workers [7], with nano anatase in a molar composition of 5.5TEOS: TiO2: 8.4NaOH: 1.43KF: 350H2O: 2.2H2SO4 produced unknown phase(s) with some ETS-10 and quartz. Using colloidal anatase with molar composition 5.5TEOS:1.0TiO 2:8.4NaOH:1.43KF:400H2O:2.2H2SO4 also produced unknown phase(s). The method of Anderson and co-workers [6] with nano anatase powder in a molar composition of 5.5SiO2: TiO 2: 5.2Na2O: 0.5K2O: 113H2O produced quartz with ETS-10 impurity. When colloidal anatase was used, with molar composition TiO2:5.5SiO2:5.2Na2O:0.5K2O:332H 2O, unreacted anatase and quartz were formed. It was hypothesized that the very low

  15. Recent advances on virtual human synthesis

    Institute of Scientific and Technical Information of China (English)

    XIA ShiHong; WANG ZhaoQi

    2009-01-01

    Virtual human is a digital representation of the geometric and behavioral property of human beings in the virtual environment generated by computer. The research goal of virtual human synthesis is to gen-erate realistic human body models and natural human motion behavior. This paper introduces the devel-opment of the related researches on these two topics, and some progresses on example based human modeling and motion synthesis, and their applications In Chinese sign language teaching, computer-aided sports training and public safety problem studying. Finally, some hot research topics in virtual human synthesis are presented.

  16. Synthesis of cyanopyridine based conjugated polymer

    Directory of Open Access Journals (Sweden)

    B. Hemavathi

    2016-06-01

    Full Text Available This data file contains the detailed synthetic procedure for the synthesis of two new cyanopyridine based conjugated polymer P1 and P2 along with the synthesis of its monomers. The synthesised polymers can be used for electroluminescence and photovoltaic (PV application. The physical data of the polymers are provided in this data file along with the morphological data of the polymer thin films. The data provided here are in association with the research article entitled ‘Cyanopyridine based conjugated polymer-synthesis and characterisation’ (Hemavathi et al., 2015 [3].

  17. Green chemistry oriented organic synthesis in water.

    Science.gov (United States)

    Simon, Marc-Olivier; Li, Chao-Jun

    2012-02-21

    The use of water as solvent features many benefits such as improving reactivities and selectivities, simplifying the workup procedures, enabling the recycling of the catalyst and allowing mild reaction conditions and protecting-group free synthesis in addition to being benign itself. In addition, exploring organic chemistry in water can lead to uncommon reactivities and selectivities complementing the organic chemists' synthetic toolbox in organic solvents. Studying chemistry in water also allows insight to be gained into Nature's way of chemical synthesis. However, using water as solvent is not always green. This tutorial review briefly discusses organic synthesis in water with a Green Chemistry perspective. PMID:22048162

  18. Green chemistry oriented organic synthesis in water.

    Science.gov (United States)

    Simon, Marc-Olivier; Li, Chao-Jun

    2012-02-21

    The use of water as solvent features many benefits such as improving reactivities and selectivities, simplifying the workup procedures, enabling the recycling of the catalyst and allowing mild reaction conditions and protecting-group free synthesis in addition to being benign itself. In addition, exploring organic chemistry in water can lead to uncommon reactivities and selectivities complementing the organic chemists' synthetic toolbox in organic solvents. Studying chemistry in water also allows insight to be gained into Nature's way of chemical synthesis. However, using water as solvent is not always green. This tutorial review briefly discusses organic synthesis in water with a Green Chemistry perspective.

  19. Improved Synthesis of Nefazodone from Phenol

    Institute of Scientific and Technical Information of China (English)

    LI Aijun; ZHOU Xueqin; LIU Dongzhi

    2006-01-01

    A route for the synthesis of nefazodone is reported. Nefazodone was obtained with an overall yield of 37.2% from phenol. The key steps involve the improved synthesis of 5-ethyl-4-(2-phenoxyethyl)-1, 2, 4-triazol-3(2H)-one, a key intermediate in the synthesis of nefazodone. The phenol was etherified with 1, 2-dichloroethane (75%), followed by iodination-amination with Nal and CH3OH-NH3(85.7%), acylation with ethyl chloroformate (95.7%) and cyclization with propionyl hydrazine (83.6%).

  20. Sonochemical Synthesis of Cobalt Ferrite Nanoparticles

    Directory of Open Access Journals (Sweden)

    Partha P. Goswami

    2013-01-01

    Full Text Available Cobalt ferrite being a hard magnetic material with high coercivity and moderate magnetization has found wide-spread applications. In this paper, we have reported the sonochemical synthesis of cobalt ferrite nanoparticles using metal acetate precursors. The ferrite synthesis occurs in three steps (hydrolysis of acetates, oxidation of hydroxides, and in situ microcalcination of metal oxides that are facilitated by physical and chemical effects of cavitation bubbles. The physical and magnetic properties of the ferrite nano-particles thus synthesized have been found to be comparable with those reported in the literature using other synthesis techniques.

  1. Filter synthesis using Genesys S/Filter

    CERN Document Server

    Rhea, Randall W

    2014-01-01

    S/Filter includes tools beyond direct synthesis, including a wide variety of both exact and approximate equivalent network transforms, methods for selecting the most desirable out of potentially thousands of synthesized alternatives, and a transform history record that simplifies design attempts requiring iteration. Very few software programs are based on direct synthesis, and the additional features of S/Filter make it a uniquely effective tool for filter design.This resource presents a practical guide to using Genesys software for microwave and RF filter design and synthesis. The focus of th

  2. Enabling N-to-C Ser/Thr Ligation for Convergent Protein Synthesis via Combining Chemical Ligation Approaches.

    Science.gov (United States)

    Lee, Chi Lung; Liu, Han; Wong, Clarence T T; Chow, Hoi Yee; Li, Xuechen

    2016-08-24

    In this article, Ser/Thr ligation(on/off) has been realized to enable N-to-C successive peptide ligations using a salicylaldehyde semicarbazone (SAL(off)) group by in situ activation with pyruvic acid of the peptide SAL(off) ester into the peptide salicylaldehyde (SAL(on)) ester. In addition, a peptide with a C-terminal thioester and N-terminal Ser or Thr as the middle peptide segment can undergo one-pot Ser/Thr ligation and native chemical ligation in the N-to-C direction. The utility of this combined ligation strategy in the N-to-C direction has been showcased through the convergent assembly of a human cytokine protein sequence, GlcNAcylated interleukin-25. PMID:27479006

  3. Synthesis

    Directory of Open Access Journals (Sweden)

    Ivonne Alonso-Lemus

    2010-01-01

    Full Text Available MCM-41 have been used to custom synthesize catalysts in because of the controllable properties, such as pore size, active phase incorporation, crystal size, and morphology, among others. In this paper, a simple and versatile method for the incorporation of platinum, ruthenium, and palladium onto Al-MCM-41 mesoporous silica by direct inclusion of various precursors was studied. M/Al-MCM-41 structure, textural properties, morphology, and elemental composition were analyzed. The results obtained indicate that the Al-MCM-41 mesoporous-ordered structure was not affected by metallic particle incorporation. High-surface areas were obtained (1131 m2/g. Metallic nanoparticles dispersion on Al-MCM-41 was homogeneous for all samples and its particles sizes were between 6 nm to 20 nm. Microscopy results show round shape particles in platinum and palladium samples; however, ruthenium catalysts exhibit a spherical and rod shapes. Electrochemical testing for Pt/Al-MCM-41 showed electrocatalytic activity for H2 oxidation which indicates that these materials can be used as a catalyst in electrochemical devices.

  4. Solventless synthesis of ruthenium nanoparticles

    Science.gov (United States)

    García-Peña, Nidia G.; Redón, Rocío; Herrera-Gomez, Alberto; Fernández-Osorio, Ana Leticia; Bravo-Sanchez, Mariela; Gomez-Sosa, Gustavo

    2015-06-01

    This paper presents a novel solventless method for the synthesis of zero-valent ruthenium nanoparticles Ru(0). The proposed method, although not entirely new in the nanomaterials world, was used for the first time to synthesize zero-valent ruthenium nanoparticles. This new approach has proved to be an environmentally friendly, clean, cheap, fast, and reproducible technique which employs low amounts of solvent. It was optimized through varying amounts of reducing salt on a determined quantity of precursor and measuring the effect of this variation on the average particle size obtained. The resulting products were fully characterized by powder XRD, TEM, HR-TEM, and XPS studies, all of which corroborated the purity of the nanoparticles achieved. In order to verify the advantages of our method over other techniques, we compared our nanoparticles with two common colloidal-synthesized ruthenium nanoparticles.

  5. Enantioselective Synthesis of (+)-Peganumine A.

    Science.gov (United States)

    Piemontesi, Cyril; Wang, Qian; Zhu, Jieping

    2016-09-01

    A gram-scale enantioselective total synthesis of (+)-peganumine A was accomplished in 7 steps from commercially available 6-methoxytryptamine. Key steps included (a) a Liebeskind-Srogl cross-coupling; (b) a one-pot construction of the tetracyclic skeleton from an ω-isocyano-γ-oxo-aldehyde via a sequence of an unprecedented C-C bond forming lactamization and a transannular condensation; (c) a one-pot organocatalytic process merging two achiral building blocks into an octacyclic structure via a sequence of enantioselective Pictet-Spengler reaction followed by a transannular cyclization. This last reaction created two spirocycles and a 2,7-diazabicyclo[2.2.1]heptan-3-one unit with excellent control of both the absolute and relative stereochemistry of the two newly created quaternary stereocenters. PMID:27558528

  6. Silica Aerogel: Synthesis and Applications

    Directory of Open Access Journals (Sweden)

    Jyoti L. Gurav

    2010-01-01

    Full Text Available Silica aerogels have drawn a lot of interest both in science and technology because of their low bulk density (up to 95% of their volume is air, hydrophobicity, low thermal conductivity, high surface area, and optical transparency. Aerogels are synthesized from molecular precursors by sol-gel processing. Special drying techniques must be applied to replace the pore liquid with air while maintaining the solid network. Supercritical drying is most common; however, recently developed methods allow removal of the liquid at atmospheric pressure after chemical modification of the inner surface of the gels, leaving only a porous silica network filled with air. Therefore, by considering the surprising properties of aerogels, the present review addresses synthesis of silica aerogels by the sol-gel method, as well as drying techniques and applications in current industrial development and scientific research.

  7. Fluid Mechanics Optimising Organic Synthesis

    Science.gov (United States)

    Leivadarou, Evgenia; Dalziel, Stuart

    2015-11-01

    The Vortex Fluidic Device (VFD) is a new ``green'' approach in the synthesis of organic chemicals with many industrial applications in biodiesel generation, cosmetics, protein folding and pharmaceutical production. The VFD is a rapidly rotating tube that can operate with a jet feeding drops of liquid reactants to the base of the tube. The aim of this project is to explain the fluid mechanics of the VFD that influence the rate of reactions. The reaction rate is intimately related to the intense shearing that promotes collision between reactant molecules. In the VFD, the highest shears are found at the bottom of the tube in the Rayleigh and the Ekman layer and at the walls in the Stewardson layers. As a step towards optimising the performance of the VFD we present experiments conducted in order to establish the minimum drop volume and maximum rotation rate for maximum axisymmetric spreading without fingering instability. PhD candidate, Department of Applied Mathematics and Theoretical Physics.

  8. Mechanochemical synthesis of cerium orthophosphate

    Institute of Scientific and Technical Information of China (English)

    A.Matraszek; I.Szczygiei; L.Macalik; J.Hanuza

    2009-01-01

    A facile,simple and rapid preparation method of cerium orthophosphate was presented.The synthesis of low-crystalline CePO4 occurred upon mixing of cerium (Ⅲ) nitrate and sodium phosphate,and was an exchange-type reaction.The phase composition of the obtained powder was checked by the XRD and FTIR methods,indicating the presence of cerium phosphate.Further investigations on thermal behavior of the synthesized cerium salt had shown that the obtained onhophosphate crystallized at first in rhabdophane-type structure.It convetted to monazite (monoclinic symmetry) during heating at the temperatures of above 600 ℃.Oxidation of Ce3+ to Ce4+ was avoided during the syntheses,as confirmed by the XPS experiments.

  9. Synthesis of B6 vitamin

    Directory of Open Access Journals (Sweden)

    Vučijak Nevena Ž.

    2009-01-01

    Full Text Available The importance of vitamin B6 has been known since its discovery in the 1940's. Chemical tests, elestrometric titration determinations, and absorption spectrum studies showed that this vitamin exists in three major chemical forms: pyridoxine (an alcohol, pyridoxal (an aldehyde, and pyridoxamine (a primary amine. Vitamin B6 is needed for more than 100 enzymes involved in protein metabolism, and it is assumed that this vitamin is cofactor of metabolic processes more important than any other substance. A deficiency of vitamin B6 in the human diet leads to severe disorders. Vitamin B6 is necessary for the proper function of the immune and nervous system, and helps the body convert protein to energy. This paper describes the history, properties and applications of vitamin B6, elucidation of chemical structure, and different procedures for synthesis of pyridoxine and pyridoxamine.

  10. Combinatorial synthesis of natural products

    DEFF Research Database (Denmark)

    Nielsen, John

    2002-01-01

    increase in application of natural products in combinatorial chemistry and vice versa. The therapeutic areas of infectious disease and oncology still dominate but many new areas are emerging. Several complex natural products have now been synthesised by solid-phase methods and have created the foundation......Combinatorial syntheses allow production of compound libraries in an expeditious and organized manner immediately applicable for high-throughput screening. Natural products possess a pedigree to justify quality and appreciation in drug discovery and development. Currently, we are seeing a rapid...... for preparation of combinatorial libraries. In other examples, natural products or intermediates have served as building blocks or scaffolds in the synthesis of complex natural products, bioactive analogues or designed hybrid molecules. Finally, structural motifs from the biologically active parent molecule have...

  11. Diversity-Oriented Organic Synthesis

    Institute of Scientific and Technical Information of China (English)

    J. Wu

    2005-01-01

    @@ 1Introduction A goal of chemical genetics is to find small molecules that modulate the individual functions of gene products with high potency and high specificity[1,2]. Natural products and natural product-derived compounds provide many of the most striking examples, particularly in terms of their specificity. It seems unlikely that natural products alone will provide the hypothetical "complete" set of small molecules that would allow the functions of all proteins, as well as their individual domains, to be determined. For chemistry to have its maximal effect on biology, efficient methods based on diversity-oriented organic synthesis for discovering this set of small molecules are in great demand(See Fig. 1).

  12. Synthesis of Reliable Telecommunication Networks

    Directory of Open Access Journals (Sweden)

    Dusan Trstensky

    2005-01-01

    Full Text Available In many application, the network designer may to know to senthesise a reliable telecommunication network. Assume that a network, denoted Gm,e has the number of nodes n and the number of edges e, and the operational probability of each edge is known. The system reliability of the network is defined to be the reliability that every pair of nodes can communicate with each other. A network synthesis problem considered in this paper is to find a network G*n,e, that maximises system reliability over the class of all networks for the classes of networks Gn,n-1, Gn,m and Gn,n+1 respectively. In addition an upper bound of maximum reliability for the networks with n-node and e-edge (e>n+2 is derived in terms of node. Computational experiments for the reliability upper are also presented. the results show, that the proposed reliability upper bound is effective.

  13. Synthesis of 5'-Aldehyde Oligonucleotide.

    Science.gov (United States)

    Lartia, Rémy

    2016-01-01

    Synthesis of oligonucleotide ending with an aldehyde functional group at their 5'-end (5'-AON) is possible for both DNA (5'-AODN) and RNA (5'-AORN) series irrespectively of the nature of the last nucleobase. The 5'-alcohol of on-support ODN is mildly oxidized under Moffat conditions. Transient protection of the resulting aldehyde by N,N'-diphenylethylenediamine derivatives allows cleavage, deprotection, and RP-HPLC purification of the protected 5'-AON. Finally, 5'-AON is deprotected by usual acetic acid treatment. In the aggregates, 5'-AON can be now synthesized and purified as routinely as non-modified ODNs, following procedures similar to the well-known "DMT-On" strategy. PMID:26967469

  14. GASP- GENERAL AVIATION SYNTHESIS PROGRAM

    Science.gov (United States)

    Galloway, T. L.

    1994-01-01

    The General Aviation Synthesis Program, GASP, was developed to perform tasks generally associated with the preliminary phase of aircraft design. GASP gives the analyst the capability of performing parametric studies in a rapid manner during preliminary design efforts. During the development of GASP, emphasis was placed on small fixed-wing aircraft employing propulsion systems varying from a single piston engine with a fixed pitch propeller through twin turboprop/turbofan systems as employed in business or transport type aircraft. The program is comprised of modules representing the various technical disciplines of design, integrated into a computational flow which ensures that the interacting effects of design variables are continuously accounted for in the aircraft sizing procedures. GASP provides a useful tool for comparing configurations, assessing aircraft performance and economics, and performing tradeoff and sensitivity studies. By utilizing GASP, the impact of various aircraft requirements and design factors may be studied in a systematic manner, with benefits being measured in terms of overall aircraft performance and economics. The GASP program consists of a control module and six "technology" submodules which perform the various independent studies required in the design of general aviation or small transport type aircraft. The six technology modules include geometry, aerodynamics, propulsion, weight and balance, mission analysis, and economics. The geometry module calculates the dimensions of the synthesized aircraft components based on such input parameters as number of passengers, aspect ratio, taper ratio, sweep angles, and thickness of wing and tail surfaces. The aerodynamics module calculates the various lift and drag coefficients of the synthesized aircraft based on inputs concerning configuration geometry, flight conditions, and type of high lift device. The propulsion module determines the engine size and performance for the synthesized aircraft

  15. Zeolite synthesis: an energetic perspective.

    Science.gov (United States)

    Zwijnenburg, Martijn A; Bromley, Stefan T

    2010-11-21

    Taking |D(H(2)O)(x)|[AlSiO(4)] based materials (where D is Li, Na, K, Rb or Cs) as an archetypal aluminosilicate system, we use accurate density functional theory calculations to demonstrate how the substitution of silicon cations in silica, with pairs of aluminium and (alkali metal) cations, changes the energetic ordering of different competing structure-types. For large alkali metal cations we further show that the formation of porous aluminosilicate structures, the so-called zeolites, is energetically favored. These findings unequivocally demonstrate that zeolites can be energetic preferred reaction products, rather than being kinetically determined, and that the size of the (hydrated) cations in the pore, be it inorganic or organic, is critical for directing zeolite synthesis.

  16. Synthesis of Lysine Methyltransferase Inhibitors

    Directory of Open Access Journals (Sweden)

    Tao eYe

    2015-07-01

    Full Text Available Lysine methyltransferase which catalyze methylation of histone and nonhistone proteins, play a crucial role in diverse biological processes and has emerged as a promising target for the development of various human diseases, including cancer, inflammation, and psychiatric disorders. However, inhibiting Lysine methyltransferases selectively has presented many challenges to medicinal chemists. During the past decade, lysine methyltransferase inhibitors covering many different structural classes have been designed and developed. In this review, we describe the development of selective, small-molecule inhibitors of lysine methyltransferases with an emphasis on their discovery and chemical synthesis. We highlight the current state of lysine methyltransferase inhibitors and discuss future directions and opportunities for lysine methyltransferase inhibitor discovery.

  17. Synthesis and Chemistry of Perfluoroalkylphosphines.

    OpenAIRE

    Al'Issa, Farouk

    2014-01-01

    The synthesis of new perfluoroalkyl-containing phosphines from the reactions of the perfluoroalkyl iodides n-C3F7I, i-C3F7I, n-C4F9I, sec-C4F9I, cyc-C6F11Br or cyc-C6F11I, n-C6F13I and n-C8F17I with R2PSiMe3 or R2PLi (R = Ph2, t-Bu2, Et2, MePh and EtPh was investigated. The new perfluoroalkyl-containing phosphines were characterised by multinuclear NMR spectroscopy. The reaction between i-Pr2P-Pi-Pr2 and i-C3F7I resulted in some i-Pr2PCF(CF3)2, 11, but an elimination process was dominant. Com...

  18. Algorithmic synthesis using Python compiler

    Science.gov (United States)

    Cieszewski, Radoslaw; Romaniuk, Ryszard; Pozniak, Krzysztof; Linczuk, Maciej

    2015-09-01

    This paper presents a python to VHDL compiler. The compiler interprets an algorithmic description of a desired behavior written in Python and translate it to VHDL. FPGA combines many benefits of both software and ASIC implementations. Like software, the programmed circuit is flexible, and can be reconfigured over the lifetime of the system. FPGAs have the potential to achieve far greater performance than software as a result of bypassing the fetch-decode-execute operations of traditional processors, and possibly exploiting a greater level of parallelism. This can be achieved by using many computational resources at the same time. Creating parallel programs implemented in FPGAs in pure HDL is difficult and time consuming. Using higher level of abstraction and High-Level Synthesis compiler implementation time can be reduced. The compiler has been implemented using the Python language. This article describes design, implementation and results of created tools.

  19. Synthesis of high purity hexanitrostilbene

    Energy Technology Data Exchange (ETDEWEB)

    Stull, T.W.

    1975-09-01

    The development of a continuous process and the apparatus for the synthesis of high purity hexanitrostilbene type I (HNS I) are described. Optimum solution concentrations and ratios were investigated, and product washing and slurrying procedures were developed to yield a high purity product. The synthesized products were evaluated against the Navy's WS-5003F specification. In addition, other tests suggested by Sandia Laboratory and/or developed in-house, were employed to enable better classification of the explosive and to assure its suitability for ultimate use. Information in this document will enable any facility to synthesize HNS I at a purity level of approximately 99.5 percent, with yields approaching 38 percent.

  20. Triboluminescence theory, synthesis, and application

    CERN Document Server

    Okoli, Okenwa; Fontenot, Ross; Hollerman, William

    2016-01-01

    This book expounds on progress made over the last 35 years in the theory, synthesis, and application of triboluminescence for creating smart structures. It presents in detail the research into utilization of the triboluminescent properties of certain crystals as new sensor systems for smart engineering structures, as well as triboluminescence-based sensor systems that have the potential to enable wireless, in-situ, real time and distributed (WIRD) structural health monitoring of composite structures. The sensor component of any structural health monitoring (SHM) technology — measures the effects of the external load/event and provides the necessary inputs for appropriate preventive/corrective action to be taken in a smart structure — sits at the heart of such a system. This volume explores advances in materials properties and structural behavior underlying creation of smart composite structures and sensor systems for structural health monitoring of critical engineering structures, such as bridges, aircraf...

  1. Melanin synthesis by Sclerotinia sclerotiorum.

    Science.gov (United States)

    Butler, Michael J; Gardiner, Richard B; Day, Alan W

    2009-01-01

    We confirmed that the melanin produced by Sclerotinia sclerotiorum is a dihydroxynaphthalene (DHN). The specific DHN melanogenesis inhibitor test that uses tricyclazole at low levels (typically 2-5 ppm) to cause a confirmatory appearance of soluble red-brown inhibition products does not work when analyzing melanin synthesis in the sclerotia of S. sclerotiorum. We demonstrated the presence of scytalone dehydratase, an enzyme specific to DHN melanogenesis, in melanized sclerotia and melanized nonsclerotial mycelia and observed formation of mycelial nonsclerotial melanin when the fungus was grown on the surface of sterilized dialysis membrane or in rich organic media. Nonsclerotial melanized hyphae in wild type and mutant strains showed the typical excretion of pigmented inhibition products of the DHN pathway in the presence of tricyclazole, and one of these products, 2-hydroxyjuglone, was identified by thin layer chromatography and spectroscopy. We report basic conditions for sclerotial melanin degradation by the white rot fungus Phanerochaete chrysosporium. PMID:19537203

  2. Synthesis gas method and apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, Sean M.; Kromer, Brian R.; Litwin, Michael M.; Rosen, Lee J.; Christie, Gervase Maxwell; Wilson, Jamie; Kosowski, Lawrence W; Robinson, Charles

    2015-11-06

    A method and apparatus for producing a synthesis gas product having one or more oxygen transport membrane elements thermally coupled to one or more catalytic reactors such that heat generated from the oxygen transport membrane element supplies endothermic heating requirements for steam methane reforming reactions occurring within the catalytic reactor through radiation and convention heat transfer. A hydrogen containing stream containing no more than 20 percent methane is combusted within the oxygen transport membrane element to produce the heat and a heated combustion product stream. The heated combustion product stream is combined with a reactant stream to form a combined stream that is subjected to the reforming within the catalytic reactor. The apparatus may include modules in which tubular membrane elements surround a central reactor tube.

  3. Anthrax carbohydrates, synthesis and uses thereof

    Energy Technology Data Exchange (ETDEWEB)

    Carlson, Russell W.; Boons, Geert-Jan; Quinn, Conrad; Vasan, Mahalakshmi; Wolfert, Margreet A.; Choudhury, Biswa; Kannenberg, Elmar; Leoff, Christine; Mehta, Alok; Saile, Elke; Rauvolfova, Jana; Wilkins, Patricia; Harvey, Alex J.

    2013-04-16

    The present invention presents the isolation, characterization and synthesis of oligosaccharides of Bacillus anthracis. Also presented are antibodies that bind to such saccharide moieties and various methods of use for such saccharide moieties and antibodies.

  4. Structured synthesis of MEMS using evolutionary approaches

    DEFF Research Database (Denmark)

    Fan, Zhun; Wang, Jiachuan; Achiche, Sofiane;

    2008-01-01

    In this paper, we discuss the hierarchy that is involved in a typical MEMS design and how evolutionary approaches can be used to automate the hierarchical synthesis process for MEMS. The paper first introduces the flow of a structured MEMS design process and emphasizes that system-level lumped......-parameter model synthesis is the first step of the MEMS synthesis process. At the system level, an approach combining bond graphs and genetic programming can lead to satisfactory design candidates as system-level models that meet the predefined behavioral specifications for designers to trade off....... Then at the physical layout synthesis level, the selection of geometric parameters for component devices and other design variables is formulated as a constrained optimization problem and addressed using a constrained genetic algorithm approach. A multiple-resonator microsystem design is used to illustrate...

  5. Solvent-Free Synthesis of New Coumarins

    Directory of Open Access Journals (Sweden)

    Redah I. Al-Bayati

    2012-01-01

    Full Text Available A solvent-free synthesis of five series of coumarin derivatives using microwave assistant is presented herein. The synthesized compounds are fully characterized by UV-VIS, FT-IR, and NMR spectroscopy.

  6. Total Synthesis of (±)-Hibiscone C

    OpenAIRE

    Ungureanu, Sinziana; Meadows, Maggie; Smith, Joel; Duff, David B.; Burgess, James M.; Goess, Brian C.

    2011-01-01

    A total synthesis of (±)- hibiscone C, one member of the furanosteroid family of natural products that also includes viridin and wortmannin, is reported. Two new pathways for formation of the key diacyl furan subunit are described.

  7. Enantioselective synthesis of tetrafluorinated ribose and fructose.

    Science.gov (United States)

    Linclau, Bruno; Boydell, A James; Timofte, Roxana S; Brown, Kylie J; Vinader, Victoria; Weymouth-Wilson, Alexander C

    2009-02-21

    A perfluoroalkylidene lithium mediated cyclisation approach for the enantioselective synthesis of a tetrafluorinated aldose (ribose) and of a tetrafluorinated ketose (fructose), both in the furanose and in the pyranose form, is described. PMID:19194597

  8. Synthesis of substituted 2-cyanoarylboronic esters

    DEFF Research Database (Denmark)

    Lysén, Morten; Hansen, Henriette M; Begtrup, Mikael;

    2006-01-01

    The synthesis of substituted 2-cyanoarylboronic esters is described via lithiation/in situ trapping of the corresponding methoxy-, trifluoromethyl-, fluoro-, chloro-, and bromobenzonitriles. The crude arylboronic esters were obtained in high yields and purities and with good regioselectivities....

  9. The First Total Synthesis of Isoliquiritin

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A first total synthesis of isoliquiritin was accomplished starting from p-hydroxy- benzaldehyde and 2,4-dihydroxyacetylphenone. The key step is condensation reaction. In synthetic process need not protect the hydroxy group of reacting substance.

  10. Albumin synthesis in protein energy malnutrition

    International Nuclear Information System (INIS)

    The dietary treatment of protein-energy malnutrition (PEM) has been designed on an empirical basis, with outcomes for successful management including body weight gain and resolution of apathy. We propose using the measurements of protein synthesis as a more objective measure of renourishment. We will therefore randomize a group of malnourished children (weigh-for-height Z score 13C-leucine and serial measurements of 13C-enrichment of albumin. Isotope infusions will be performed on days one and three, following a standard three hour fast. Since albumin synthesis is reduced under the influence of cytokines which mediate the inflammatory response, results will be stratified according to the presence or absence of clinically apparent infections. We hypothesize that the provision of added dietary protein will optimize albumin synthesis rates in PEM as well as attenuate the reduction in albumin synthesis seen in the presence of infections. (author). 20 refs

  11. Synthesis of novel spiro--lactams

    Indian Academy of Sciences (India)

    Renu Arora; P Venugopalan; S S Bari

    2010-03-01

    A new synthetic approach for spiro--lactams by cyclization of cis-3-allyl-3-benzylthio--lactams is presented. The reaction involves step-wise electrophilic addition-dealkylation sequence giving stereospecific synthesis of C-3-spiro--lactams.

  12. BIOMIMETIC STRATEGIES IN ORGANIC SYNTHESIS. TERPENES

    OpenAIRE

    V. Kulcitki

    2012-01-01

    The current paper represents an outline of the selected contributions to the biomimetic procedures and approaches for the synthesis of terpenes with complex structure and diverse functionalisation pattern. These include homologation strategies, cyclisations, rearrangements, as well as biomimetic remote functionalisations.

  13. Synthesis of Pyrrole-Imidazole Polyamide

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    One simple and versatile method is established for the synthesis of DNA recognition molecules-polyamides containing alternating N-methylpyrrole and N-methylimidazole without necessitating NH2- group protection.

  14. Synthesis of the isoquinoline alkaloid, crispine C

    OpenAIRE

    Blair, A.; Stevenson, L; Sutherland, A

    2012-01-01

    The first total synthesis of the isoquinoline alkaloid, crispine C is described in seven steps using a Henry reaction and the Pictet–Gams variant of the Bischler–Napieralski reaction to effect the key transformations.

  15. Behavioral program synthesis with genetic programming

    CERN Document Server

    Krawiec, Krzysztof

    2016-01-01

    Genetic programming (GP) is a popular heuristic methodology of program synthesis with origins in evolutionary computation. In this generate-and-test approach, candidate programs are iteratively produced and evaluated. The latter involves running programs on tests, where they exhibit complex behaviors reflected in changes of variables, registers, or memory. That behavior not only ultimately determines program output, but may also reveal its `hidden qualities' and important characteristics of the considered synthesis problem. However, the conventional GP is oblivious to most of that information and usually cares only about the number of tests passed by a program. This `evaluation bottleneck' leaves search algorithm underinformed about the actual and potential qualities of candidate programs. This book proposes behavioral program synthesis, a conceptual framework that opens GP to detailed information on program behavior in order to make program synthesis more efficient. Several existing and novel mechanisms subs...

  16. Regional Synthesis for State Wildlife Action Plans

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The North Atlantic LCC and Northeast states are developing a synthesis of regional conservation information for State Wildlife Action Plan (SWAP) revisions....

  17. Synthesis and Biological Activity of Philanthotoxin Analogs

    Institute of Scientific and Technical Information of China (English)

    Yong An ZHANG; Ke Zhong LIU; Deng Yuan WANG; Yu Zhu WANG; Liang Jian QU; Chang Jin ZHU

    2006-01-01

    The synthesis of four analogs of philanthotoxin is described. The preliminary bioassay showed that these compounds all had good insecticidal activities, and the compound 6a had the best killing effect.

  18. Green Synthesis of Nanocrystals and Nanocomposites

    Science.gov (United States)

    Metal nanomaterials have attracted considerable attention because of their unique magnetic, optical, electrical, and catalytic properties and their potential applications in nanoelectronics as well as in various wet chemical synthesis methods. There is also great interest in synt...

  19. Copper catalysed synthesis of indolylquinazolinone alkaloid bouchardatine

    Indian Academy of Sciences (India)

    Mayavan Viji; Rajagopal Nagarajan

    2014-07-01

    We describe the total synthesis of indolylquinazolinone alkaloid bouchardatine and some of the quinazolinone derivatives. The aerobic oxidation induced by copper(I) bromide, followed by Vilsmeier-Haack formylation gives the natural product bouchardatine alkaloid in good yield.

  20. Silicone containing copolymers: Synthesis, properties and applications

    OpenAIRE

    Yılgör, Emel; Yılgör, İskender

    2013-01-01

    Accepted Manuscript Title: Silicone containing copolymers: Synthesis, properties and applications Author: Emel Yilgor Iskender Yilgor PII: S0079-6700(13)00141-X DOI: http://dx.doi.org/doi:10.1016/j.progpolymsci.2013.11.003 Reference: JPPS 848 To appear in: Progress in Polymer Science Received date: 1-8-2013 Revised date: 4-11-2013 Accepted date: 8-11-2013 Please cite this article as: Yilgor E, Yilgor I, Silicone containing copolymers: Synthesis, properties ...

  1. Tools for chemical synthesis in microsystems

    OpenAIRE

    Jensen, Klavs F.; Newman, Stephen G.; Reizman, Brandon Jacob

    2014-01-01

    Chemical synthesis in microsystems has evolved from simple proof-of-principle examples to become a general technique in academia and industry. Numerous such “flow chemistry” applications are now found in pharmaceutical and fine chemical synthesis. Much of the development has been based on systems employing macroscopic flow components and tubes, rather than the integrated chip technology envisioned by the lab-on-a-chip community. We review the major developments in systems for flow chemistry a...

  2. A Facile Synthesis of Pyrrolidine Derivatives

    Institute of Scientific and Technical Information of China (English)

    SHAO Zhi-Hui; CHEN Jing-Bo; WANG Cheng-Ying; LIU Xiao-Long; REN Zhou-Yang; TU Yong-Qiang; ZHANG Hong-Bin

    2003-01-01

    @@ The Amaryllidaceae alkaloids have attracted considerable attention for their interesting biological activities. [1] Many of these tyrosine derived alkaloids[2] incorporate a hexahydroindole moiety in the structural skeletons. New approaches towards the synthesis of hexahydroindole core have been a topical interest for the synthetic community.Herein we report an experimentally very simple method for the synthesis of hexahydroindole by aminocylization. Four kinds of N-substituted have been demonstrate to be effective to this cyclization. The results were summarized in Figure 1.

  3. Singing synthesis and the Vocal Tract Organ

    OpenAIRE

    Howard, David Martin

    2014-01-01

    Vocal synthesis has been the subject of investigation since the late 18th century when von Kempelen produced his mechanical ‘speaking machine’. The advert of electronics has enabled a number of different methods of voice synthesis to be realized in practice. Recently with the advent of 3-D printing and magnetic resonance imaging of human vocal tracts, it has been possible to create synthetic vocal sounds that combine both mechanical (3-D printed tracts) and electronic (synthesized larynx soun...

  4. Discoveries and diversions in natural product synthesis

    OpenAIRE

    Reisman, Sarah E.

    2013-01-01

    Our lab. seeks to discover, develop, and study new chem. reactions within the context of natural product total synthesis. The chem. synthesis of natural products enables the study of their biol. properties, and can provide access to synthetic derivs. with improved therapeutic properties or that can serve as mechanistic probes. Importantly, these synthetic undertakings often highlight shortcomings of the existing state-of-the-art and inspire the discovery of new chem. Our lab. has ...

  5. An introduction to statistical parametric speech synthesis

    Indian Academy of Sciences (India)

    Simon King

    2011-10-01

    Statistical parametric speech synthesis, based on hidden Markov model-like models, has become competitive with established concatenative techniques over the last few years. This paper offers a non-mathematical introduction to this method of speech synthesis. It is intended to be complementary to the wide range of excellent technical publications already available. Rather than offer a comprehensive literature review, this paper instead gives a small number of carefully chosen references which are good starting points for further reading.

  6. Efficient and Facile Synthesis of ( ± )-Salvirecognine

    Institute of Scientific and Technical Information of China (English)

    PENG Xuan-Jia; SHE Xue-Gong; BIE Ping-Yan; PAN Xin-Fu

    2003-01-01

    @@ Salvirecognine (7) is a diterpene isolated from Salvia recognita[1] which has been the subject of continued and growing interest, due to the range of biological activities shown by many members of this family. [2] In order to study further relationships between the structure and biological activity of the diterpene compounds and as an extension of diterpenoid synthesis in our laboratory, [3,4] the first total synthesis of the title compound was achieved by an efficient and facile route (Scheme 1).

  7. Synthesis of Polyfunctionalized 4H-Pyrans

    Directory of Open Access Journals (Sweden)

    Manisha Bihani

    2013-01-01

    Full Text Available Amberlyst A21 catalyzed one-pot three-component coupling of aldehyde and malononitrile with active methylene compounds such as acetylacetone and ethyl acetoacetate for the synthesis of pharmaceutically important polyfunctionalized 4H-pyrans has been reported. Simple experimental procedure, no chromatographic purification, no hazardous organic solvents, easy recovery and reusability of the catalyst, and room temperature reaction conditions are some of the highlights of this protocol for the synthesis of pharmaceutically relevant focused libraries.

  8. Microchannel systems for fine organic synthesis

    Science.gov (United States)

    Makarshin, L. L.; Pai, Z. P.; Parmon, V. N.

    2016-02-01

    Characteristic features of application of microchannel systems in organic synthesis are analyzed. The advantages of such systems over conventional chemical engineering equipment, especially for small-scale processes that require fast implementation in industry to obtain small quantities of the product, are shown. Particular examples of successful use of microchannel reactors for various types of organic synthesis are given, primary attention being devoted to the design features of microchannel reactors. The bibliography includes 118 references.

  9. Audible Aliasing Distortion in Digital Audio Synthesis

    OpenAIRE

    J. Schimmel

    2012-01-01

    This paper deals with aliasing distortion in digital audio signal synthesis of classic periodic waveforms with infinite Fourier series, for electronic musical instruments. When these waveforms are generated in the digital domain then the aliasing appears due to its unlimited bandwidth. There are several techniques for the synthesis of these signals that have been designed to avoid or reduce the aliasing distortion. However, these techniques have high computing demands. One can say that today'...

  10. First synthesis of antitumoral dasyscyphin B

    OpenAIRE

    Akhaouzan, Ali; Fern??ndez, Antonio; Mansour, Ahmed I.; ??lvarez, Esteban; Haid??ur, Ali; ??lvarez-Manzaneda, Ram??n; Chahboun, Rachid; ??lvarez-Manzaneda, Enrique

    2013-01-01

    The first synthesis of dasyscyphin B, an antitumoral metabolite obtained from the ascomycete Dasyscyphus niveus, has been achieved starting from commercial abietic acid. The key steps of the synthetic sequence are the diastereoselective ??-methylation of a ketoaldehyde, followed by an intramolecular aldol condensation and the further Diels???Alder cycloaddition of a dienol ester. The procedure reported will allow the synthesis of related metabolites functionalized in the A ring.

  11. SYNTHESIS OF COPPER NANOPARTICLES BY ASPERGILLUS SPECIES

    OpenAIRE

    Kantabathini Venkata Pavani; Nandigam Srujana; Guntur Preethi; Tandale Swati

    2013-01-01

    Recent developments in the biosynthesis of nanomaterials have demonstrated the important role of microorganisms in nanotechnology. The organisms show a unique potential in environmentally friendly production and accumulation of nanoparticles with different shapes and sizes. The present study proposed a green process for synthesis of copper nanoparticles using Aspergillus species. Syntheses of copper nanoparticles were characterized by UV-visible spectroscopy. The extracellular synthesis of co...

  12. SYNTHESIS OF COPPER NANOPARTICLES BY ASPERGILLUS SPECIES

    Directory of Open Access Journals (Sweden)

    Kantabathini Venkata Pavani

    2013-06-01

    Full Text Available Recent developments in the biosynthesis of nanomaterials have demonstrated the important role of microorganisms in nanotechnology. The organisms show a unique potential in environmentally friendly production and accumulation of nanoparticles with different shapes and sizes. The present study proposed a green process for synthesis of copper nanoparticles using Aspergillus species. Syntheses of copper nanoparticles were characterized by UV-visible spectroscopy. The extracellular synthesis of copper nanoparticles was characterized by scanning electron microscopy and Transmission electron microscopy.

  13. Speech synthesis, speech simulation and speech science

    OpenAIRE

    Huckvale, M.

    2002-01-01

    Speech synthesis research has been transformed in recent years through the exploitation of speech corpora – both for statistical modelling and as a source of signals for concatenative synthesis. This revolution in methodology and the new techniques it brings calls into question the received wisdom that better computer voice output will come from a better understanding of how humans produce speech. This paper discusses the relationship between this new technology of simulated speech and the tr...

  14. A Short Synthesis of Bisabolane Sesquiterpenes

    Directory of Open Access Journals (Sweden)

    Zhen-Ting Du

    2011-09-01

    Full Text Available A facile total synthesis of three members of the bisabolane sesquiterpene family, namely (±-curcumene, (±-xanthorrhizol and (±-curcuhydroquinone had been achieved in high overall yield. The synthesis used bromobenzene derivatives as starting materials. The halogen-lithium exchange followed by addition of isoprenylacetone and reduction of the obtained carbinols are the key steps of the synthetic pathway. This synthetic approach provides a new route to the bisabolane sesquiterpenes.

  15. Synthesis of aminopyrimidylindoles structurally related to meridianins

    OpenAIRE

    Rossignol, Emilie; Youssef, Ali; Moreau, Pascale; Prudhomme, Michelle; Anizon, Fabrice

    2007-01-01

    The synthesis of new meridianin derivatives substituted at the C-5′ position of the 2-aminopyrimidine ring by various aryl groups and substituted or not by a methyl group on the indole nitrogen is described. The 2-aminopyrimidine ring was obtained via a Bredereck synthesis. Aryl groups were introduced by Suzuki cross-coupling after bromination of the 2-aminopyrimidine ring at the C-5′ position

  16. Synthesis of dehydrobenzoannulenes with pyrene core

    Indian Academy of Sciences (India)

    Antony Joseph; Gandikota Venkataramana; Sethuraman Sankararaman

    2012-05-01

    Synthesis of dehydrobenzoannulenes (DBAs) with pyrene core from 1,8-diethynylpyrene and 1,3,6,8-tetraethynylpyrene as building blocks is reported. A sequence involving Sonogashira coupling, Corey- Fuchs reaction and oxidative coupling (Eglinton coupling) is used for the synthesis of pyrene-based dehydrobenzoannulenes. Due to the presence of pyrenechromophore these DBAs and their precursors are highly fluorescent and emit in the visible region, due to extended conjugation of the acetylenic units with the pyrene core.

  17. Prebiotic RNA Synthesis by Montmorillonite Catalysis

    OpenAIRE

    2014-01-01

    This review summarizes our recent findings on the role of mineral salts in prebiotic RNA synthesis, which is catalyzed by montmorillonite clay minerals. The clay minerals not only catalyze the synthesis of RNA but also facilitate homochiral selection. Preliminary data of these findings have been presented at the “Horizontal Gene Transfer and the Last Universal Common Ancestor (LUCA)” conference at the Open University, Milton Keynes, UK, 5–6 September 2013. The objective of this meeting was to...

  18. Efficient Synthesis of Optically Active Alcohols

    Institute of Scientific and Technical Information of China (English)

    J.S. Chen; Z.R. Dong; Y.Y. Li; B.Z. Li; Y. Xing; W.Y. Shen; G. Chen; X.Q. Zhang; J. X. Gao

    2005-01-01

    @@ 1Introduction Optically active secondary alcohols are versatile building blocks for synthesis of unnatural biological active compounds and functional materials. Therefore, study on efficient synthesis of optically active alcohols is becoming an important subject in synthetic organic chemistry. Catalytic asymmetric reduction of carbonyl compounds is a practical method to create chiral alcohols. For the past decades, a large number of catalytic methods have been developed to achieve this goal.

  19. Facile synthesis of carbon nanotube/natural bentonite composites as a stable catalyst for styrene synthesis.

    Science.gov (United States)

    Rinaldi, Ali; Zhang, Jian; Mizera, Jan; Girgsdies, Frank; Wang, Ning; Hamid, Sharifah Bee Abd; Schlögl, Robert; Su, Dang Sheng

    2008-12-28

    Natural bentonite mineral, without any wet chemical treatment, was used directly to catalyze the growth of multi-wall CNTs and the produced CNTs/bentonite as an integrated composite stably catalyzed the oxidative dehydrogenation reaction over a long period of time; this concept provides a highly economical way for large-scale synthesis of nanocarbons and manufacture of styrene synthesis catalysts. PMID:19057768

  20. De Novo Synthesis of Furanose Sugars: Catalytic Asymmetric Synthesis of Apiose and Apiose-Containing Oligosaccharides.

    Science.gov (United States)

    Kim, Mijin; Kang, Soyeong; Rhee, Young Ho

    2016-08-01

    A de novo synthetic method towards apiose, a structurally unusual furanose, is reported. The key feature is sequential metal catalysis consisting of the palladium-catalyzed asymmetric intermolecular hydroalkoxylation of an alkoxyallene and subsequent ring-closing metathesis (RCM). This strategy enabled the efficient synthesis of various apiose-containing disaccharides and a unique convergent synthesis of trisaccharides. PMID:27381592

  1. Synthesis of the C(18) -norditerpenoid alkaloid neofinaconitine: a lesson in convergent synthesis planning.

    Science.gov (United States)

    Liu, Xiao-Yu; Chen, David Y-K

    2014-01-20

    Hexacyclic framework: The total synthesis of the complex C18 -norditerpenoid alkaloid neofinaconitine has been achieved by a convergent approach. This remarkable synthesis featured two Diels-Alder cycloadditions and subsequent Mannich-type N-acyliminium and radical cyclizations to establish the unique hexacyclic core structure of the target molecule.

  2. Titanium(III) chloride mediated synthesis of furan derivatives: Synthesis of (±)-evodone

    Indian Academy of Sciences (India)

    S K Mandal; M Paira; S C Roy

    2010-05-01

    Titanocene(III) chloride (Cp2TiCl) mediated one-pot synthesis of furan derivatives has been accomplished. This radical method has been applied for the synthesis of a furanomonoterpene, evodone. Ti(III) species was prepared in situ from commercially available titanocene dichloride (Cp2TiCl2) and zinc dust in THF.

  3. First Total Synthesis of Gliomasolide C and Formal Total Synthesis of Sch-725674.

    Science.gov (United States)

    Seetharamsingh, B; Khairnar, Pankaj V; Reddy, D Srinivasa

    2016-01-01

    Syntheses of two 14-membered macrolides Sch-725674 and Gliomasolide C are described here. The first total synthesis of Gliomasolide C, the short synthesis of Sch-725674, and regioselective Wacker oxidation of internal olefin are the highlights of this disclosure. In addition, a key macrocycle with orthogonal functionalities was designed and synthesized on a gram scale for the generation of analogues. PMID:26633579

  4. The Solvent Selection framework: solvents for organic synthesis, separation processes and ionic-organic synthesis

    DEFF Research Database (Denmark)

    Mitrofanov, Igor; Sansonetti, Sascha; Abildskov, Jens;

    2012-01-01

    problems are presented: 1) solvent selection and design for organic synthesis, 2) solvent screening and design of solvent mixtures for pharmaceutical applications and 3) ionic liquids selection and design as solvents. The application of the framework is highlighted successfully through case studies...... focusing on solvent replacement problem in organic synthesis and solvent mixture design for ibuprofen respectively....

  5. Absence of cholesterol synthesis as contrasted with the presence of fatty acid synthesis in some arthropods

    NARCIS (Netherlands)

    Zandee, D.I.

    1967-01-01

    1. 1. After administration of acetate-1-14C absence of cholesterol synthesis was demonstrated in the lobster Homarus gammarus (L.), the spider Avicularia avicularia (L.) and in the millepede Graphidostreptus tumuliporus (Karsch). 2. 2. However, the animals utilize acetate for the synthesis of fatty

  6. Synthesis of bridged diketopiperazines by using the persistent radical effect and a formal synthesis of bicyclomycin.

    Science.gov (United States)

    Amatov, Tynchtyk; Pohl, Radek; Císařová, Ivana; Jahn, Ullrich

    2015-10-01

    A conceptually new and unified approach to diverse bridged diketopiperazines (DKPs) with widely variable ring sizes was developed by taking advantage of the persistent radical effect. This method enables synthesis of the core structures of bridged DKP alkaloids and was applied to a formal synthesis of the antibiotic bicyclomycin.

  7. Synthesis of derivatives of tetronic acid and pulvinic acid. Total synthesis of norbadione A

    International Nuclear Information System (INIS)

    When vegetables like mushrooms are contaminated by radioactive caesium 137, this radioactive caesium is associated to norbadione A, a natural pigment present in two mushroom species and which can be used as a caesium decorporation agent or maybe as protection agent against ionizing radiations. Within this perspective, this research report describes the biosynthesis and the structure and properties of the norbadione A and of pulvinic acids (physicochemical properties, anti-oxidizing properties). Then, it presents the various tetronic acids (3-acyl-, 3-alkyl-, 3-alkoxy-, 3-aryl-tetronic acids and non 3-substituted tetronic acids), their synthesis path as they are described in the literature, and presents a new synthesis approach using a tandem reaction (with different esters or hydroxy esters) and the synthesis of tetronic acids. The author also proposes a new synthesis way for methyl pulvinates, and finally reports the work on the development of a total synthesis of the norbadione A

  8. Compliant Mechanism Synthesis by Using Elastic Similitude

    Institute of Scientific and Technical Information of China (English)

    HANKE Uwe; HAMPEL Peter; COMSA Andrei; MODLER Niels; MODLER Karl-Heinz

    2015-01-01

    Compliant mechanisms have several advantages, especially smaller number of elements and therefore less movable joints. The flexural members furthermore allow an integration of special functions like balancing or locking. Especially fiber reinforced materials exhibit a wide range of function integration considering their compliance in passive as well active applications. To take advantage of compliant elements in applications a robust synthesis tool is needed. The synthesis based on topology optimization method or the pseudo rigid body approach leads to complex structures. Considering the use of fiber reinforced material a synthesis approach which leads to less complex structures is more suitable. For building up simple structures, with only one cantilever beam as compliant element(B) a graphical approach using the elastic similitude is the most efficient method. A step-by-step synthesis procedure is presented to synthesize compliant mechanisms with rotatory joints(R) and prismatic joints(P) to develop RRB/PRB-and RPB-linkages. Using the elastic similitude to implement these results into a graphical synthesis algorithm is the innovation part of this paper. It can be shown that this approach leads to a comfortable handling of beam elements during the synthesis, where the two free parameters can be directly coupled to scale and fix the orientation of the beam element. This advantage inherently shortens the development process. In giving an example the focus lies of the experimental approach, which also shows that the simple BERNOULLI beam model is valid and so the synthesis by using the elastic similitude. The method is presented and discussed by using an application for a cup holder mechanism made of fiber reinforced material.

  9. 2,5-Dimethoxy­benzaldehyde thio­semicarbazone

    OpenAIRE

    Fun, Hoong-Kun; Jebas, Samuel Robinson; D’Silva, E. Deepak; Patil, P. S.; S. M. Dharmaprakash

    2008-01-01

    In the title mol­ecule, C10H13N3O2S, the dihedral angle between benzene and –N—C(=S)—N—N=C– planes is 9.20 (6)°. The two meth­oxy groups are coplanar with the benzene ring [C—O—C—C torsion angles of −2.31 (18) and −6.45 (17)°]. In the crystal structure, mol­ecules are linked by inter­molecular N—H⋯S, N—H⋯O and C—H⋯O hydrogen bonds, forming a three-dimensional network.

  10. 5-Hy­droxy-2-nitro­benzaldehyde thio­semicarbazone (HNBATSC)

    OpenAIRE

    M. Sivasankar Reddy; Sarala, Y.; Jagadeesh, M.; Das, Samar K.; Varada Reddy Ammireddy

    2014-01-01

    The asymmetric unit of the title compound, C8H8N4O3S, consists of two independent molecules. Each molecule is approximately planar with dihedral angles of 8.71 (3) and 1.50 (2)° between the aromatic ring and the thiosemicarbazide moiety while the NO2 group makes dihedral angles of 29.27 (3) and 17.78 (3)° with the benzene ring. In the crystal, the molecules are linked by N—H...S, O—H...O and N—H...O hydrogen bonds, forming two-dimensional networks parallel to (100).

  11. 5-Chloro-2-hy­droxy­benzaldehyde thio­semicarbazone

    OpenAIRE

    Kargar, Hadi; Kia, Reza; Akkurt, Mehmet; Büyükgüngör, Orhan

    2010-01-01

    In the title compound, C8H8ClN3OS, the whole mol­ecule assumes a planar structure, with an r.m.s. deviation of 0.108 (2) Å, and an intra­molecular O—H⋯N hydrogen bond generates and S(6) and ring motif. In the crystal structure, each of two pairs of inter­molecular N—H⋯S hydrogen bonds connects two mol­ecules, forming inversion dimers with R 2 2(8) motifs.

  12. 4-Hy­droxy-3-meth­oxy­benzaldehyde thio­semicarbazone

    OpenAIRE

    Inke Jess; Christian Näther; Bárbara Regina Santos Feitosa; Adriano Bof de Oliveira

    2013-01-01

    In the title compound, C9H11N3S, there is an intramolecular O—H...O hydrogen bond involving the OH group and the adjacent methoxy O atom. The molecule is essentially planar, with the maximum deviation from the mean plane of the non-H atoms being 0.1127 (14) Å for the methyl C atom. In the crystal, molecules are connected via centrosymmetric pairs of N—H...S and O—H...O hydrogen bonds into a two-dimensional network parallel to (10-3).

  13. 2-Hy­droxy-4-meth­oxy­benzaldehyde thio­semicarbazone

    OpenAIRE

    Yu-Mei Hao

    2010-01-01

    The title Schiff base compound, C9H11N3O2S, was prepared by the reaction of equimolar quantities of 2-hydroxy-4-methoxybenzaldehyde with thiosemicarbazide in methanol. The molecule adopts a trans configuration with respect to the azomethine group and an intramolecular O—H...N hydrogen bond generates an S(6) ring. In the crystal structure, molecules are linked through intermolecular N—H...O and N—H...S hydrogen bonds, forming a three-dimensional network.

  14. 5-Bromo-2-hy­droxy­benzaldehyde thio­semicarbazone

    OpenAIRE

    Kargar, Hadi; Kia, Reza; Akkurt, Mehmet; Büyükgüngör, Orhan

    2010-01-01

    The mol­ecule of the title compound, C8H8BrN3OS, is close to being planar, with maximum deviations of −0.127 (3) and 0.135 (5) Å for the N atoms of the –NH– and NH2– groups, respectively. Intra­molecular N—H⋯N and O—H⋯N hydrogen bonds to the same acceptor N atom generate S(5) and S(6) ring motifs. In the crystal structure, mol­ecules are connected into [010] chains by pairs of N—H⋯S hydrogen bonds with R 2 2(8) graph-set motifs. The crystal used for data collection was found to be an inversio...

  15. 5-Bromo-1H-indole-3-carbaldehyde thio­semicarbazone

    OpenAIRE

    Seik Weng Ng; Hapipah Mohd Ali; Mohd. Razali Rizal

    2008-01-01

    In the essentially planar title mol­ecule, C10H9BrN4S, the C=N double bond is in a trans configuration. In the crystal structure, the S atom acts as a hydrogen-bond acceptor for the aromatic NH, aliphatic NH and terminal NH2 groups of three symmetry-related mol­ecules, forming a weak hydrogen-bonded layer structure.

  16. 2-Chloro-5-nitro­benzaldehyde thio­semicarbazone

    OpenAIRE

    Yu-Mei Hao

    2010-01-01

    The title Schiff base compound, C8H7ClN4O2S, was prepared by the reaction of equimolar quantities of 2-chloro-5-nitrobenzaldehyde with thiosemicarbazide in methanol. The molecule adopts a trans configuration with respect to the azomethine group and the dihedral angle between the benzene ring and the thiosemicarbazide group is 6.8 (3)°. In the crystal, molecules are linked through intermolecular N—H...S hydrogen bonds, forming chains propagating in [010].

  17. 1-(2H-1,3-Benzodioxol-5-yl)ethanone thio­semicarbazone

    OpenAIRE

    de Oliveira, Adriano Bof; de Farias, Renan Lira; Näther, Christian; Jess, Inke; Bresolin, Leandro

    2013-01-01

    In the title compound, C10H11N3O2S, the 1,3-benzodioxole and hydrazinecarbothio­amide fragments are nearly planar [(mean deviations from planarity for non-H atoms of 0.0325 (12) Å and 0.0707 (10) Å, respectively] and subtend a dihedral angle of 29.06 (5)°. In the crystal, mol­ecules are linked by pairs of almost linear N—H⋯S hydrogen bonds, forming inversion dimers. These dimers are additionally connected by weaker and strongly bent N—H⋯S inter­actions into chains along [101]. There is one ad...

  18. (E)-2-Hydr­oxy-3-methoxy­benzaldehyde thio­semicarbazone

    OpenAIRE

    Zhao, Ren-Gao; Zhang, Wei; Li, Ji-Kun; Zhang, Li-ya

    2008-01-01

    In the title compound, C9H11N3O2S, intra­molecular O—H⋯O and N—H⋯N hydrogen bonds contribute to the planarity of the mol­ecular skeleton. Inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into zigzag chains along the b axis; these mol­ecules are futher paired by π–π inter­actions [centroid–centroid distance 4.495 (5) Å]. The crystal structure also exhibits weak inter­molecular N—H⋯S and O—H⋯S hydrogen bonds.

  19. Density functional theory (B3LYP/6-311+G** study of some semicarbazones formation mechanism

    Directory of Open Access Journals (Sweden)

    Uzairu Adamu

    2015-12-01

    Full Text Available Mechanism of formations of (E-2-(1-phenylethylidenehydrazinecarboxamide, 2-cyclohexyldenehydrazinecarboxamide, (Z-2-(1-phenylpropan-2-ylidenehydrazinecarboxamide, (Z-2-(hexan-2-ylidenehydrazinecarboxamide and (E-2-((Ephenylallylidenehydrazinecarboxamide has been investigated using density functional theory (B3LYP/6-311+G**. The mechanism was found to involve four elementary steps comprising one intermediate and two transition states. The study indicates a two-step reaction pathway, comprising an intermediate and two activated complexes for all the compounds. The mechanism involves two transition (bimolecular and unimolecular and consecutive (bimolecular and unimolecular schemes. The formation was found to occur sequentially; a fast pre-equilibrium between the reactants and the prereactive complex is established, followed by an internal rearrangement leading to elimination of a water molecule. The thermodynamic data were obtained for the stationary points and the kinetic study shows the unimolecular consecutive step to be the rate determining step in all the formation mechanisms. A general rate law was also established for the formation pathways.

  20. Velocimetry signal synthesis with fringen.

    Energy Technology Data Exchange (ETDEWEB)

    Dolan, Daniel H., III

    2011-02-01

    An important part of velocimetry analysis is the recovery of a known velocity history from simulated data signals. The fringen program synthesizes VISAR and PDV signals, given a specified velocity history, using exact formulations for the optical signal. Time-dependent light conditions, non-ideal measurement conditions, and various diagnostic limitations (noise, etc.) may be incorporated into the simulated signals. This report describes the fringen program, which performs forward VISAR (Velocity Interferometer System for Any Reflector) and PDV (Photonic Doppler Velocimetry, also known as heterodyne velocimetry) analysis. Nearly all effects that might occur in VISAR/PDV measurement of a single velocity can be modeled by fringen. The program operates in MATLAB, either within a graphical interface or as a user-callable function. The current stable version of fringen is 0.3, which was released in October 2010. The following sections describe the operation and use of fringen. Section 2 gives a brief overview of VISAR and PDV synthesis. Section 3 illustrates the graphical and console interface of fringen. Section 4 presents several example uses of the program. Section 5 summarizes program capabilities and discusses potential future work.

  1. Synthesis of Ordered Biosilica Materials

    Institute of Scientific and Technical Information of China (English)

    WANG,Li-Jun(王荔军); WANG,Yun-Hua(王运华); LI,Min(李敏); FAN,Ming-Sheng(范明生); ZHANG,Fu-Suo(张福锁); WU,Xue-Min(吴学民); YANG,Wen-Sheng(杨文胜); LI,Tie-Jin(李铁津)

    2002-01-01

    Biogenic silica with amazing diversity of nanostructure shells,fibers and granules in diatoms and sponges is mediated by proteins and polysaccharides and forms at ambient pressure and temperatures. Chemical synthetic methods, in contrast,have to rely on extreme pH and/or surfactants to induce the condensation of silica precursors into specific patterns. One kind of benign synthesis method through plant cell wall template-directed ordered biosilica materials under ambient conditions is intriguing in this context. Organized silica materials in intercellular spaces of epidermal cells of tall fescue leaves were synthesized through molecular recognition between Si-OH and polysaccharide-OH or glycoprotein-OH of main components of plant cell walls and cellular processing as well when Si(OEt)4 was supplied rather than monosilicic acid. The biosynthesis of structural silica in tall fescue plant was correlated with the Si species applied, reflecting the slower coudensation from tetraethoxrsilane (TEOS) and thus providing greater opportunities for structural control by the underlying matrix of cell walls. The composition was estimated by energy dispersive Xray (EDX) spectra on a scanning electron microscope. All organized structures showed carbon, oxygen and silicon peaks,indicating that their formations differ from natural siliceous process.

  2. The Chemical Synthesis of Discodermolide

    Science.gov (United States)

    Paterson, I.; Florence, G. J.

    The marine sponge-derived polyketide discodermolide is a potent antimitotic agent that represents a promising natural product lead structure in the treatment of cancer. Discodermolide shares the same microtubule-stabilising mechanism of action as Taxol®, inhibits the growth of solid tumours in animal models and shows synergy with Taxol. The pronounced cytotoxicity of discodermolide, which is maintained against cancer cell lines that display resistance to Taxol and other drugs, combined with its scarce availability from its natural source, has fuelled significant academic and industrial interest in devising a practical total synthesis as a means of ensuring a sustainable supply for drug development. This chapter surveys the various total syntheses of discodermolide that have been completed over the period 1993-2007, focusing on the strategies employed for introduction of the multiple stereocentres and achieving control over the alkene geometry, along with the various methods used for realising the pivotal fragment couplings to assemble progressively the full carbon skeleton. This dedicated synthetic effort has triumphed in removing the supply problem for discodermolide, providing sufficient material for extensive biological studies and enabling its early stage clinical development, as well as facilitating SAR studies for lead optimisation.

  3. Asymmetric total synthesis of vindoline.

    Science.gov (United States)

    Kato, Daisuke; Sasaki, Yoshikazu; Boger, Dale L

    2010-03-24

    A concise asymmetric total synthesis of (-)-vindoline (1) is detailed based on a tandem intramolecular [4+2]/[3+2] cycloaddition cascade of a 1,3,4-oxadiazole inspired by the natural product structure, in which the tether linking the initiating dienophile and oxadiazole bears a chiral substituent that controls the facial selectivity of the initiating Diels-Alder reaction and sets absolute stereochemistry of the remaining six stereocenters in the cascade cycloadduct. This key reaction introduces three rings and four C-C bonds central to the pentacyclic ring system setting all six stereocenters and introducing essentially all the functionality found in the natural product in a single step. Implementation of the approach also required the development of a unique ring expansion reaction to provide a six-membered ring suitably functionalized for introduction of the Delta (6, 7)-double bond found in the core structure of vindoline and defined our use of a protected hydroxymethyl group as the substituent used to control the stereochemical course of the cycloaddition cascade.

  4. Asymmetric catalysis in organic synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Reilly, S.D.; Click, D.R.; Grumbine, S.K.; Scott, B.L.; Watkins, J.G.

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The goal of the project was to prepare new catalyst systems, which would perform chemical reactions in an enantioselective manner so as to produce only one of the possible optical isomers of the product molecule. The authors have investigated the use of lanthanide metals bearing both diolate and Schiff-base ligands as catalysts for the enantioselective reduction of prochiral ketones to secondary alcohols. The ligands were prepared from cheap, readily available starting materials, and their synthesis was performed in a ''modular'' manner such that tailoring of specific groups within the ligand could be carried out without repeating the entire synthetic procedure. In addition, they have developed a new ligand system for Group IV and lanthanide-based olefin polymerization catalysts. The ligand system is easily prepared from readily available starting materials and offers the opportunity to rapidly prepare a wide range of closely related ligands that differ only in their substitution patterns at an aromatic ring. When attached to a metal center, the ligand system has the potential to carry out polymerization reactions in a stereocontrolled manner.

  5. 78 FR 64253 - NASA Asteroid Initiative Idea Synthesis Workshop

    Science.gov (United States)

    2013-10-28

    ... SPACE ADMINISTRATION NASA Asteroid Initiative Idea Synthesis Workshop AGENCY: National Aeronautics and Space Administration. ACTION: Notice of Continuation of public conference to examine ideas in response... Administration announces that the agency will resume the NASA Asteroid Initiative Idea Synthesis...

  6. A novel and practical asymmetric synthesis of dapoxetine hydrochloride

    Directory of Open Access Journals (Sweden)

    Yijun Zhu

    2015-12-01

    Full Text Available A novel and practical asymmetric synthesis of dapoxetine hydrochloride by using the chiral auxiliary (S-tert-butanesulfinamide was explored. The synthesis was concise, mild, and easy to perform. The overall yield and stereoselectivity were excellent.

  7. Recent Advances in the Synthesis of 2-Pyrones

    OpenAIRE

    Jong Seok Lee

    2015-01-01

    The present review summarizes the recent progresses in the synthesis of 2-pyrones and the application to the synthesis of marine natural products. Especially, much attention was placed on the transition metal catalyzed synthetic methodologies in this review.

  8. RNA synthesis during cleavage of the Lymnaea egg

    NARCIS (Netherlands)

    Biggelaar, J.A.M. van den

    1971-01-01

    In eggs of Lymnaea RNA synthesis can be detected autoradiographically from the 8- to the 16-cell stage. From the 16- to the 24-cell stage distinct nucleoli reappear which are immediately engaged in RNA synthesis.

  9. Modelling of the enzymatic kinetically controlled synthesis of cephalexin

    NARCIS (Netherlands)

    Schroën, C.G.P.H.; Fretz, C.B.; Bruin, de V.H.; Berendsen, W.; Moody, H.M.; Roos, E.C.; Roon, van J.L.; Kroon, P.J.; Strubel, M.; Janssen, A.E.M.; Tramper, J.

    2002-01-01

    In this study the influence of diffusion limitation on enzymatic kinetically controlled cephalexin synthesis from phenylglycine amide and 7-aminodeacetoxycephalosporinic acid (7-ADCA) was investigated systematically. It was found that if diffusion limitation occurred, both the synthesis/hydrolysis r

  10. Synthesis and analysis of processes with electrolyte mixtures

    DEFF Research Database (Denmark)

    Thomsen, Kaj; Gani, Rafiqul; Rasmussen, Peter

    1995-01-01

    A computer aided system for synthesis, design and simulation of crystallization and fractional crystallization processes with electrolyte mixtures is presented. The synthesis methodology is based on the use of computed solubility diagrams for the corresponding electrolyte systems....

  11. Sustainable synthesis of monodispersed spinel nano-ferrites

    Science.gov (United States)

    A sustainable approach for the synthesis of various monodispersed spinel ferrite nanoparticles has been developed that occurs at water-toluene interface under both conventional and microwave hydrothermal conditions. This general synthesis procedure utilizes readily available and ...

  12. Intestinal apolipoprotein synthesis in the newborn piglet.

    Science.gov (United States)

    Black, D D; Rohwer-Nutter, P L

    1991-01-01

    To determine the effects of dietary and biliary lipid absorption on intestinal apo B-48 and apo A-I synthesis in the newborn piglet, 2-d-old female piglets were prepared with a duodenal infusion catheter. After recovery, animals were given either low triglyceride (Vivonex; VIV group) or high triglyceride (Intralipid; FAT group) diets by continuous intraduodenal infusion for 24 h. A bile-diverted group was also studied. Segments of proximal jejunum and distal ileum were then pulse-radiolabeled in vivo with 3H-leucine. Mucosal apo B-48 and apo A-I were immunoprecipitated, and apoprotein synthesis was expressed as percentage of total protein synthesis. Mucosal apoprotein content (ng apoprotein/microgram total protein) was measured by competitive ELISA assays. In jejunum and ileum, apo B-48 synthesis was not different in the three groups. However, apo B content increased 2.4-fold in jejunum and 1.7-fold in ileum in the FAT group compared with the VIV group. Immunoblotting revealed the majority of jejunal apo B to be apo B-48, not apo B-100 from contaminating plasma lipoproteins, in all three experimental groups. Bile-diverted animals had decreased jejunal apo B content compared with the VIV group. Jejunal apo A-I synthesis and content were approximately 2-fold higher in FAT animals compared with the VIV group. Although ileal apo A-I synthesis was also 2-fold higher in the FAT group, apo A-I content was not different from the VIV group. Neither jejunal nor ileal apo A-I synthesis was significantly affected by bile diversion, even though jejunal apo A-I content was decreased by over two thirds compared with the VIV animals. In the newborn piglet, intestinal synthesis of apo B-48 and apo A-I is differentially regulated by luminal lipid absorption. Although fat feeding and bile diversion regulate mucosal apo B-48 content, synthesis is unchanged, indicating a posttranslational regulatory mechanism.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1900361

  13. Synthesis of Siloxanes Directly from Amorphous Silica

    International Nuclear Information System (INIS)

    A direct synthesis of oligomeric-siloxanes from amorphous silica has been achieved. The compound prepared was caedonal-siloxane. Cardonal is a mono hydroxyphenolic compound with a bulky group in the meta position. It was derived as a by-product from the renewable resources cashew nut shell liquid (CNSL). In the synthesis, one pot synthesis was carried out by using ethylene glycol (EG) as solvent. In the reaction ethylene glycol served as a primary precursor chelating ligand in the synthesised product. The one pot synthesis was enhanced by the strong base, triethylenetetramine (TETA) which served as the promoter catalyst. In the synthesis, optimal conditions were established on the basic of the yield percent of organo-siloxane compounds with respect to the variation of the weight fraction of TETA and to the variation of reaction time. Experimental runs were carried out at (ca 210 2c) which was nearly above the boiling point of the solvent. The substituted organo-silicon compounds obtained were characterized by FT- ir, Thermal analysis, XRD and SEM.

  14. Reaction path synthesis methodology for waste minimization

    Institute of Scientific and Technical Information of China (English)

    HU; Shanying; LI; Mingheng; LI; Yourun; SHEN; Jingzhu; LIU

    2004-01-01

    It is a key step for reducing waste generation in chemical processes to design optimal reaction paths. In this paper, methods of waste minimization for reaction path synthesis problems are proposed to realize eco-industrial production mode with minimum waste emission. A new conception of simple stoichiometric reaction is presented for reaction path synthesis problem. All simple stoichiometric reactions can be obtained by mathematical transformation for atom matrix of a reaction system. Based on the conception, a two-tier optimization method for complex reaction path synthesis problems is addressed. The first step is to determine the economic optimal overall reactions, and the second step to decompose each overall reaction into several sub-reactions and find out the best thermodynamic feasible reaction path. Further, a method of reaction path synthesis with waste closed-cycle is proposed based on simple stoichiometric reactions for achieving zero waste emission to poly-generation problem of multi-products. Case studies show that the proposed methods can efficiently solve practical reaction path synthesis problems.

  15. Synthesis of cubane based energetic molecules

    Science.gov (United States)

    Schmitt, Robert J.; Bottaro, Jeffrey C.; Penwell, Paul E.

    1993-02-01

    The need to pack more power with less weight into less space in tomorrow's weapons drove this program for the synthesis of super energetic materials. Our original impetus was a program based solely on the energetic properties of cubane. However, in the course of our studies here and in a parallel ONR sponsored program, we discovered and developed an alternative oxidizer to cubyl based systems, the dinitramide salts. We will report on our developments in the synthesis of new oxidizers based on cubane and dinitramide. In this research, we developed new methods for the functionalization of the cubane nucleus and synthesized new energetic cubanes. We developed several new routes for the synthesis of the dinitramino group. Our work on the preparation of the dinitramide group led to the synthesis of the dinitramide ion, and as a consequence ammonium dinitramide. We have in turn used this synthesis to prepare cubane ammonium dinitramide salts. We synthesized cubane-1,4bis-(ammonium dinitramide) and cubane1,2,4,7-tetrakis(ammonium dinitramide) as well as several other dinitramide salts.

  16. Nineteen-step total synthesis of (+)-phorbol.

    Science.gov (United States)

    Kawamura, Shuhei; Chu, Hang; Felding, Jakob; Baran, Phil S

    2016-04-01

    Phorbol, the flagship member of the tigliane diterpene family, has been known for over 80 years and has attracted attention from many chemists and biologists owing to its intriguing chemical structure and the medicinal potential of phorbol esters. Access to useful quantities of phorbol and related analogues has relied on isolation from natural sources and semisynthesis. Despite efforts spanning 40 years, chemical synthesis has been unable to compete with these strategies, owing to its complexity and unusual placement of oxygen atoms. Purely synthetic enantiopure phorbol has remained elusive, and biological synthesis has not led to even the simplest members of this terpene family. Recently, the chemical syntheses of eudesmanes, germacrenes, taxanes and ingenanes have all benefited from a strategy inspired by the logic of two-phase terpene biosynthesis in which powerful C-C bond constructions and C-H bond oxidations go hand in hand. Here we implement a two-phase terpene synthesis strategy to achieve enantiospecific total synthesis of (+)-phorbol in only 19 steps from the abundant monoterpene (+)-3-carene. The purpose of this synthesis route is not to displace isolation or semisynthesis as a means of generating the natural product per se, but rather to enable access to analogues containing unique placements of oxygen atoms that are otherwise inaccessible. PMID:27007853

  17. ANALYSIS-BASED SPARSE RECONSTRUCTION WITH SYNTHESIS-BASED SOLVERS

    OpenAIRE

    Cleju, Nicolae; Jafari, Maria,; Plumbley, Mark D.

    2012-01-01

    Analysis based reconstruction has recently been introduced as an alternative to the well-known synthesis sparsity model used in a variety of signal processing areas. In this paper we convert the analysis exact-sparse reconstruction problem to an equivalent synthesis recovery problem with a set of additional constraints. We are therefore able to use existing synthesis-based algorithms for analysis-based exact-sparse recovery. We call this the Analysis-By-Synthesis (ABS) approach. We evaluate o...

  18. Vector synthesis problem of random geometry antenna differentiation conditions

    OpenAIRE

    Mishchenko, S. E.

    2007-01-01

    The problem definition of general random geometry continuous and discontinuous antenna vector synthesis is discussed. Conditions are formulated which allow presenting the initial antenna vector synthesis problem in the form of array of some scalar synthesis problems while locating the antenna in the free space and near the surface. On plane, cylinder and sphere examples antenna synthesis problems division possibilities of scalar problems are examined.

  19. Hyponatremia in rats induces downregulation of vasopressin synthesis.

    OpenAIRE

    Robinson, A G; Roberts, M. M.; Evron, W A; Verbalis, J G; Sherman, T G

    1990-01-01

    Hyponatremia due to inappropriate secretion of vasopressin is a common disorder in human pathophysiology, but vasopressin synthesis during hypoosmolality has not been investigated. We used a new method to quantitate synthesis of vasopressin in rats after 3, 7, and 14 d of hyponatremia induced by administering dDAVP (a vasopressin agonist) and a liquid diet. Vasopressin synthesis was completely turned off by 7 d. Vasopressin mRNA levels in the hypothalamus paralleled the reduction in synthesis...

  20. 33 CFR 279.8 - Synthesis and analysis.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Synthesis and analysis. 279.8... DEFENSE RESOURCE USE: ESTABLISHMENT OF OBJECTIVES § 279.8 Synthesis and analysis. (a) Option, synthesis and analysis. The project resources and market area information should be aggregated and analyzed...

  1. Allium sativum (garlic) inhibits lipid synthesis by Candida albicans.

    OpenAIRE

    Adetumbi, M; Javor, G T; Lau, B H

    1986-01-01

    The effect of aqueous garlic extract on the macromolecular synthesis of Candida albicans was studied. Protein and nucleic acid syntheses were inhibited to the same extent as growth, but lipid synthesis was completely arrested. Blockage of lipid synthesis is likely an important component of the anticandidal activity of garlic.

  2. Effect of Instruction on ESL Students' Synthesis Writing

    Science.gov (United States)

    Zhang, Cui

    2013-01-01

    Synthesis writing has become the focus of much greater attention in the past 10 years in L2 EAP contexts. However, research on L2 synthesis writing has been limited, especially with respect to treatment studies that relate writing instruction to the development of synthesis writing abilities. To address this research gap, the present study…

  3. Advancements in Research Synthesis Methods: From a Methodologically Inclusive Perspective

    Science.gov (United States)

    Suri, Harsh; Clarke, David

    2009-01-01

    The dominant literature on research synthesis methods has positivist and neo-positivist origins. In recent years, the landscape of research synthesis methods has changed rapidly to become inclusive. This article highlights methodologically inclusive advancements in research synthesis methods. Attention is drawn to insights from interpretive,…

  4. Total Synthesis of a Diacetonide Derivative of Thuggacin A.

    Science.gov (United States)

    Yadav, Jhillu S; Dutta, Palash

    2016-03-01

    A highly stereoselective total synthesis of the diacetonide derivative of the antibiotic thuggacin A has been described. The synthesis features the stereoselective Stille cross-coupling reaction to set up the whole carbon framework, aldol condensation to construct the highly substituted conjugated diene, non-Evans syn aldol, CBS reduction, Hantzsch's thiazole synthesis, Horner-Wadsworth-Emmons reaction, and Shiina's macrolactonization. PMID:26856208

  5. Chemo-enzymatic peptide synthesis : bioprocess engineering aspects

    NARCIS (Netherlands)

    Vossenberg, P.

    2012-01-01

      Peptides, in particular oligopeptides, play an important role in the fields of health care, nutrition and cosmetics. Chemical synthesis is currently the most mature technique for the synthesis of peptides that range in length from 5 to 80 amino acids. Chemical synthesis is, however, expected

  6. An efficient synthesis of loline alkaloids

    Science.gov (United States)

    Cakmak, Mesut; Mayer, Peter; Trauner, Dirk

    2011-07-01

    Loline (1) is a small alkaloid that, in spite of its simple-looking structure, has posed surprising challenges to synthetic chemists. It has been known for more than a century and has been the subject of extensive biological investigations, but only two total syntheses have been achieved to date. Here, we report an asymmetric total synthesis of loline that, with less then ten steps, is remarkably short. Our synthesis incorporates a Sharpless epoxidation, a Grubbs olefin metathesis and an unprecedented transannular aminobromination, which converts an eight-membered cyclic carbamate into a bromopyrrolizidine. The synthesis is marked by a high degree of chemo- and stereoselectivity and gives access to several members of the loline alkaloid family. It delivers sufficient material to support a programme aimed at studying the complex interactions between plants, fungi, insects and bacteria brokered by loline alkaloids.

  7. Green Chemistry Techniques for Gold Nanoparticles Synthesis

    Science.gov (United States)

    Cannavino, Sarah A.; King, Christy A.; Ferrara, Davon W.

    Gold nanoparticles (AuNPs) are often utilized in many technological and research applications ranging from the detection of tumors, molecular and biological sensors, and as nanoantennas to probe physical processes. As these applications move from the research laboratory to industrial settings, there is a need to develop efficient and sustainable synthesis techniques. Recent research has shown that several food products and beverages containing polyphenols, a common antioxidant, can be used as reducing agents in the synthesis of AuNPs in solution. In this study, we explore a variety of products to determine which allow for the most reproducible solution of nanoparticles based on the size and shapes of particles present. We analyzed the AuNPs solutions using extinction spectroscopy and atomic force microscopy. We also develop a laboratory activity to introduce introductory chemistry and physics students to AuNP synthesis techniques and analysis.

  8. Quantum chemistry-assisted synthesis route development

    International Nuclear Information System (INIS)

    We have been investigating “quantum chemistry-assisted synthesis route development” using in silico screenings and applied the method to several targets. Another example was conducted to develop synthesis routes for a urea derivative, namely 1-(4-(trifluoromethyl)-2-oxo-2H-chromen-7-yl)urea. While five synthesis routes were examined, only three routes passed the second in silico screening. Among them, the reaction of 7-amino-4-(trifluoromethyl)-2H-chromen-2-one and O-methyl carbamate with BF3 as an additive was ranked as the first choice for synthetic work. We were able to experimentally obtain the target compound even though its yield was as low as 21 %. The theoretical result was thus consistent with that observed. The summary of transition state data base (TSDB) is also provided. TSDB is the key to reducing time of in silico screenings

  9. Alkoxyallenes as building blocks for organic synthesis.

    Science.gov (United States)

    Zimmer, Reinhold; Reissig, Hans-Ulrich

    2014-05-01

    Alkoxyallenes are unusually versatile C3 building blocks in organic synthesis. Hence this tutorial review summarizes the most important transformations, including subsequent reactions and their applications in the synthesis of relevant compounds, e.g. natural products. The reactivity patterns involved and the synthons derived from alkoxyallenes are presented. Often alkoxyallenes can serve as substitutes of acrolein or acrolein acetals, utilisation of which has already led to interesting products. Most important is the use of lithiated alkoxyallenes which smoothly react with a variety of electrophiles and lead to products with unique substitution patterns. The heterocycles or carbocycles formed are intermediates for the stereoselective synthesis of natural products or for the preparation of other structurally relevant compounds. The different synthons being put into practice by the use of lithiated alkoxyallenes in these variations will be discussed.

  10. Towards automatic synthesis of linear algebra programs

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, J. M.

    1979-01-01

    Automating the writing of efficient computer programs from an abstract specification of the computation that they are to perform is discussed. Advantages offered by automatic synthesis of programs include economy, reliability, and improved service. The synthesis of simple linear algebra programs is considered in general and then illustrated for the usual matrix product, a column-oriented matrix product, a rank-one update matrix product, and a program to multiply three matrices. The accumulation of inner products and transformational implementation of program synthesis addressed. The discussion attempts to illustrate both the general strategy of the syntheses and how various tactics can be adapted to make the syntheses proceed deterministically to programs that are optimal with respect to certain criteria. (RWR)

  11. Synthesis of aromatic cytokinins for plant biotechnology.

    Science.gov (United States)

    Plíhalová, Lucie; Vylíčilová, Hana; Doležal, Karel; Zahajská, Lenka; Zatloukal, Marek; Strnad, Miroslav

    2016-09-25

    Cytokinins represent an important group of plant growth regulators that can modulate several biotechnological processes owing to their ability to influence almost all stages of plant development and growth. In addition, the use of purine based cytokinins with aromatic substituent in C6 position of the purine moiety in tissue culture techniques is currently experiencing a surge in interest, made possible by the ongoing systematic synthesis and study of these compounds. This review article outlines progress in the synthesis of aromatic cytokinins, the in vitro and in vivo effects of these substances and insights gleaned from their synthesis. As the purine moiety in these compounds can be substituted at several positions, we examine each of the substitution possibilities in relation to the derivatives prepared so far. The discussion highlights the gradual simplification of their preparation in relation to their application in practice and summarizes the relevant organic chemistry literature and published patents. PMID:26703810

  12. Quantum chemistry-assisted synthesis route development

    Energy Technology Data Exchange (ETDEWEB)

    Hori, Kenji; Sumimoto, Michinori [Graduate School of Science and Engineering, Yamaguchi University, Tokiwadai, Ube, Yamaguchi 755-8611 (Japan); Murafuji, Toshihiro [Graduate School of Medicine, Yamaguchi University, Yamaguchi, Yamaguchi 753-8512 (Japan)

    2015-12-31

    We have been investigating “quantum chemistry-assisted synthesis route development” using in silico screenings and applied the method to several targets. Another example was conducted to develop synthesis routes for a urea derivative, namely 1-(4-(trifluoromethyl)-2-oxo-2H-chromen-7-yl)urea. While five synthesis routes were examined, only three routes passed the second in silico screening. Among them, the reaction of 7-amino-4-(trifluoromethyl)-2H-chromen-2-one and O-methyl carbamate with BF{sub 3} as an additive was ranked as the first choice for synthetic work. We were able to experimentally obtain the target compound even though its yield was as low as 21 %. The theoretical result was thus consistent with that observed. The summary of transition state data base (TSDB) is also provided. TSDB is the key to reducing time of in silico screenings.

  13. Using texture synthesis in fractal pattern design

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Traditional fractal pattern design has some disadvantages such as inability to effectively reflect the characteristics of real scenery and texture. We propose a novel pattern design technique combining fractal geometry and image texture synthesis to solve these problems. We have improved Wei and Levoy (2000)'s texture synthesis algorithm by first using two-dimensional autocorrelation function to analyze the structure and distribution of textures, and then determining the size of L neighborhood.Several special fractal sets were adopted and HSL (Hue, Saturation, and Light) color space was chosen. The fractal structure was used to manipulate the texture synthesis in HSL color space where the pattern's color can be adjusted conveniently. Experiments showed that patterns with different styles and different color characteristics can be more efficiently generated using the new technique.

  14. Synthesis of the Marine Pyrroloiminoquinone Alkaloids, Discorhabdins

    Directory of Open Access Journals (Sweden)

    Yasufumi Wada

    2010-04-01

    Full Text Available Manynatural products with biologically interesting structures have been isolated from marine animals and plants such as sponges, corals, worms, etc. Some of them are discorhabdin alkaloids. The discorhabdin alkaloids (discorhabdin A-X, isolated from marine sponges, have a unique structure with azacarbocyclic spirocyclohexanone and pyrroloiminoquinone units. Due to their prominent potent antitumor activity, discorhabdins have attracted considerable attention. Many studies have been reported toward the synthesis of discorhabdins. We have accomplished the first total synthesis of discorhabdin A (1, having the strongest activity in vitro among discorhabdins in 2003. In 2009, we have also accomplished the first total synthesis of prianosin B (2, having the 16,17-dehydropyrroloiminoquinone moiety, by a novel dehydrogenation reaction with a catalytic amount of NaN3. These synthetic studies, as well as syntheses of the discorhabdins by various chemists to-date, are reviewed here.

  15. Synthesis and Understanding of Novel Catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Stair, Peter C. [Northwestern University

    2013-07-09

    The research took advantage of our capabilities to perform in-situ and operando Raman spectroscopy on complex systems along with our developing expertise in the synthesis of uniform, supported metal oxide materials to investigate relationships between the catalytically active oxide composition, atomic structure, and support and the corresponding chemical and catalytic properties. The project was organized into two efforts: 1) Synthesis of novel catalyst materials by atomic layer deposition (ALD). 2) Spectroscopic and chemical investigations of coke formation and catalyst deactivation. ALD synthesis was combined with conventional physical characterization, Raman spectroscopy, and probe molecule chemisorption to study the effect of supported metal oxide composition and atomic structure on acid-base and catalytic properties. Operando Raman spectroscopy studies of olefin polymerization leading to coke formation and catalyst deactivation clarified the mechanism of coke formation by acid catalysts.

  16. Synthesis of Electromagnetic Metasurfaces: Principles and Illustrations

    CERN Document Server

    Achouri, Karim; Gupta, Shulabh; Lavigne, Guillaume; Salem, Mohamed Ahmed; Caloz, Christophe

    2015-01-01

    The paper presents partial overview of the mathematical synthesis and the physical realization of metasurfaces, and related illustrative examples. The synthesis consists in determining the exact tensorial surface susceptibility functions of the metasurface, based on generalized sheet transition conditions, while the realization deals with both metallic and dielectric scattering particle structures. The examples demonstrate the capabilities of the synthesis and realization techniques, thereby showing the plethora of possible metasurface field transmission and subsequent applications. The first example is the design of two diffraction engineering birefringent metasurfaces performing polarization beam splitting and orbital angular momentum multiplexing, respectively. Next, we discuss the concept of the "transistor" metasurface, which is an electromagnetic linear switch based on destructive interferences. Then, we introduce a non-reciprocal non-gyrotropic metasurface using a pick-up circuit radiator (PCR) archite...

  17. Ethylene synthesis and sensitivity in crop plants

    Science.gov (United States)

    Klassen, Stephen P.; Bugbee, Bruce

    2004-01-01

    Closed and semi-closed plant growth chambers have long been used in studies of plant and crop physiology. These studies include the measurement of photosynthesis and transpiration via photosynthetic gas exchange. Unfortunately, other gaseous products of plant metabolism can accumulate in these chambers and cause artifacts in the measurements. The most important of these gaseous byproducts is the plant hormone ethylene (C2H4). In spite of hundreds of manuscripts on ethylene, we still have a limited understanding of the synthesis rates throughout the plant life cycle. We also have a poor understanding of the sensitivity of intact, rapidly growing plants to ethylene. We know ethylene synthesis and sensitivity are influenced by both biotic and abiotic stresses, but such whole plant responses have not been accurately quantified. Here we present an overview of basic studies on ethylene synthesis and sensitivity.

  18. Investigations into low pressure methanol synthesis

    DEFF Research Database (Denmark)

    Sharafutdinov, Irek

    The central topic of this work has been synthesis, characterization and optimization of novel Ni-Ga based catalysts for hydrogenation of CO2 to methanol. The overall goal was to search for materials that could be used as a low temperature (and low pressure) methanol synthesis catalyst....... This is required for small scale delocalized methanol production sites, where installation of energy demanding compression units should be avoided. The work was triggered by DFT calculations, which showed that certain bimetallic systems are active towards methanol synthesis from CO2 and H2 at ambient pressure....... Among them, Ni-Ga has been chosen, primarily due to low price of constituent metals. After the preliminary optimization work, an optimal catalyst composition and preparation method has been suggested. Indeed, for an optimal catalyst, which is a SiO2 supported Ni-Ga prepared from a solution of nitrates...

  19. Exergetical Evaluation of Biobased Synthesis Pathways

    Directory of Open Access Journals (Sweden)

    Philipp Frenzel

    2014-01-01

    Full Text Available The vast majority of today’s chemical products are based on crude oil. An attractive and sustainable alternative feedstock is biomass. Since crude oil and biomass differ in various properties, new synthesis pathways and processes have to be developed. In order to prioritize limited resources for research and development (R & D, their economic potential must be estimated in the early stages of development. A suitable measure for an estimation of the economic potential is based on exergy balances. Different structures of synthesis pathways characterised by the chemical exergy of the main components are evaluated. Based on a detailed evaluation of the underlying processes, general recommendations for future bio-based synthesis pathways are derived.

  20. Inorganic materials synthesis in ionic liquids

    Directory of Open Access Journals (Sweden)

    Christoph Janiak

    2014-01-01

    Full Text Available The field of "inorganic materials from ionic liquids" (ILs is a young and dynamically growing research area for less than 10 years. The ionothermal synthesis in ILs is often connected with the preparation of nanomaterials, the use of microwave heating and in part also ultrasound. Inorganic material synthesis in ILs allows obtaining phases which are not accessible in conventional organic or aqueous solvents or with standard methods of solid-state chemistry or under such mild conditions. Cases at hand include "ligand-free" metal nanoparticles without added stabilizing capping ligands, inorganic or inorganic-organic hybrid solid-state compounds, large polyhedral clusters and exfoliated graphene from low-temperature synthesis. There are great expectations that ILs open routes towards new, possibly unknown, inorganic materials with advantageous properties that cannot (or only with great difficulty be made via conventional processes.