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Sample records for synthesized alkannin derivative

  1. Syntheses of F-18 Labeled Fluoroalkyltyrosine Derivatives

    International Nuclear Information System (INIS)

    Moon, Byung Seok; Lee, Kyo Chul; Yang, Seung Dae; Chun, Kwon Soo; Chi, Dae Yoon

    2005-01-01

    Positron emission tomography (PET) offers the highest resolution of all nuclear medicine imaging modalities and allows quantitation of tracer concentration in tissues. For more than 60 years, some of C-11 or F-18 labeled amino acids have been synthesized and evaluated for potential use in oncology, neurology and psychiatric disorders. Besides, a variety of radioisotope labeled amino acids have proven to be useful for imaging tumors, especially for brain tumor, lung tumor and breast tumor. These amino acids can be subdivided into two categories. The first category is represented by radiolabled naturally occurring amino acids and structurally similar analogues. Although these radiolabeled amino acids have proven useful in detecting brain and systemic tumors, it is susceptible to in vivo metabolism through multiple pathways that give rise to numerous radiolabled metabolites. On the other side, structurally similar amino acid analogues have some significant advantages over the natural amino acids. These nonnatural amino acids are not metabolized, which simplifieds the kinetic analysis of their uptake. On the basis of the promising results obtained with these nonnatural amino acids in preclinical studies, recent efforts have focused on the development of new F-18 labeled nonnatural amino acids. Recently, O-(2-[ 18 F]Fluoroethyl)-L-tyrosine (FET), O-(3-[ 18 F]Fluoropropyl)-L-tyrosine (FPT) were developed and evaluated among structurally similar to a new amino acid analogue. FET has shown high uptake in activated inflammatory cells using an experimental acute abscess model and in inflammation within lymph nodes. FPT was superior to FDG and had a slight advantage over FET in the differentiation of tumor from inflammation, and, like FET, it appeared to be a potential amino acid tracer for tumor imaging with PET. In this paper, we elected to introduce fluoroethyl and fluoropropyl groups at the R 1 positions and OCH 3 at R 2 position to the same effect of FET. Herein, we wish

  2. Syntheses and pyrolytic studies of salicylate derivatives of ...

    African Journals Online (AJOL)

    New salicylate derivatives of heteronucleic-μ-oxoisopropoxide [SnO2AlB(OPri)4] have been synthesized by the thermal condensation of μ-oxoisopropoxide and methyl/ethyl/phenyl/phenyl ethyl salicylates in different molar ratios (1:1-1:2) yielding the compounds of the type [SnO2AlB(OPri)4-n(RSAL)n] (where n is 1-2 and ...

  3. Androgenic-anabolic activities of some new synthesized steroidal pyrane, pyridine and thiopyrimidine derivatives.

    Science.gov (United States)

    Abdalla, Mohamed M; Amr, Abd El-Galil E; Al-Omar, Mohamed A; Hussain, Azza A; Amer, Mohamed S

    2014-01-01

    In continuation of our previous work, fused steroidal derivatives with pyrane, pyridine, pyrimidine moieties were synthesized and evaluated as androgenic-anabolic agents. Some of the newly synthesized compounds are exhibited pronounced androgenic-anabolic activities.

  4. Newly synthesized benzanthrone derivatives as prospective fluorescent membrane probes

    International Nuclear Information System (INIS)

    Zhytniakivska, Olga; Trusova, Valeriya; Gorbenko, Galyna; Kirilova, Elena; Kalnina, Inta; Kirilov, Georgiy; Kinnunen, Paavo

    2014-01-01

    Fluorescence spectral properties of a series of novel benzanthrone derivatives have been explored in lipid bilayers composed of zwitterionic lipid phosphatidylcholine (PC) and its mixtures with cholesterol (Chol) and anionic phospholipid cardiolipin (CL). Analysis of partition coefficients showed that all the examined compounds possess rather high lipid-associating ability, with the amidino derivatives exhibiting stronger membrane partitioning compared with the aminobenzanthrones. To understand how benzanthrone partition properties correlate with their structure, quantitative structure property relationship (QSPR) analysis was performed involving a range of quantum chemical molecular descriptors. -- Highlights: • Benzanthrone partitioning into lipid bilayer correlates with lipophilicity of the dyes. • Partition properties of benzanthrones depend on the dye dipole moment. • Amidino derivatives exhibit higher membrane affinity than aminobenzanthrones

  5. Syntheses and anti-microbial evaluation of new quinoline scaffold derived pyrimidine derivatives

    Directory of Open Access Journals (Sweden)

    Shikha S. Dave

    2016-09-01

    Full Text Available A series of diversely substituted chalcones derived from a quinoline scaffold, e.g. (E-3-(2-chloroquinolin-3-yl-1-(2-hydroxyphenyl prop-2-en-1-one and its pyrimidine analogues e.g. 2-[2-amino-6-(2-chloroquinolin-3-yl-5,6-dihydropyrimidin-4-yl]phenols have been prepared by condensation of 2-chloro-3-formyl quinoline with differently substituted 2-hydroxy acetophenones and further treatment with guanidine carbonate. All the newly synthesized compounds have been evaluated for their in vitro growth inhibitory activity against Escherichia coli, Pseudomonas vulgaris, Bacillus subtilis, Staphylococcus aureus, Staphylococcus typhi, Candida albicans, Aspergillus niger and Pseudomonas chrysogenum.

  6. The Syntheses of Some Novel (Naphthalen-1-yl-selenylacetic Acid Derivatives

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    Lemi Türker

    2005-08-01

    Full Text Available Some new (naphthalen-1-yl-selenylacetic acids derivatives 7a-d have been synthesized by two different methods, using naphthylselenols or naphthylselenocyanates. The structures of the products were investigated by spectroscopic methods.

  7. New Potentially Active Pyrazinamide Derivatives Synthesized Under Microwave Conditions

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    Ondrej Jandourek

    2014-07-01

    Full Text Available A series of 18 N-alkyl substituted 3-aminopyrazine-2-carboxamides was prepared in this work according to previously experimentally set and proven conditions using microwave assisted synthesis methodology. This approach for the aminodehalogenation reaction was chosen due to higher yields and shorter reaction times compared to organic reactions with conventional heating. Antimycobacterial, antibacterial, antifungal and photosynthetic electron transport (PET inhibiting in vitro activities of these compounds were investigated. Experiments for the determination of lipophilicity were also performed. Only a small number of substances with alicyclic side chain showed activity against fungi which was the same or higher than standards and the biological efficacy of the compounds increased with rising lipophilicity. Nine pyrazinamide derivatives also inhibited PET in spinach chloroplasts and the IC50 values of these compounds varied in the range from 14.3 to 1590.0 μmol/L. The inhibitory activity was connected not only with the lipophilicity, but also with the presence of secondary amine fragment bounded to the pyrazine ring. Structure-activity relationships are discussed as well.

  8. New Piperazine Derivatives Synthesized from Thio-Substituted Polyhalogeno-2-nitro-1,3-butadienes

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    S. Goksin Aydinli

    2010-01-01

    Full Text Available It is known that polyhalogeno-nitro-1,3-butadienes are important starting materials for the synthesis of polyfunctionalized bioactive heterocycles. Novel N,S-substituted nitrobutadienes (4a-j were synthesized from the reaction of the monothio-substituted nitrodiene derivatives (2a and (2b with some piperazine derivatives. These new compounds are stable and the structures of these products were characterized by spectroscopic data. The structure of the novel N,S-substituted nitrodiene compound (4g synthesized in this study was also elucidated by single crystal x-ray analysis.

  9. Glycerol Containing Triacetylborate Mediated Syntheses of Novel 2-Heterostyryl Benzimidazole Derivatives: A Green Approach

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    Ashok Kumar Taduri

    2014-01-01

    Full Text Available A very simple, mild, efficient, and novel green methodology has been developed for the syntheses of some 2-hetero/styryl-benzimidazoles. Title compounds were synthesized by the condensation of o-phenylenediamine with cinnamic acids at 150–180°C for 5-6 h using glycerol containing triacetylborate (10–20 mol% as the reaction medium. In an alternative approach, condensation of 2-methylbenzimidazole derivatives with aromatic aldehydes was done using glycerol containing triacetylborate (10–20 mol% as the reaction medium.

  10. Syntheses, Characterization and Antimicrobial Evaluation of Some 1, 3, 5-Trisubustituted Pyrazole Derivatives

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    Vertika Gautam

    2010-01-01

    Full Text Available A series of 1, 3, 5-trisubustituted pyrazole derivatives were synthesized and screened for antimicrobial activity. The compounds (2j-o were evaluated against two gram-positive and two gram-negative bacteria and one fungus, at concentrations of 10 µg/mL and 50 µg/mL. The compounds were founds to be inactive against P. aeruginosa and A. niger but exhibited moderate activity against B. subtilis, E. coli and S. aureus. It can be concluded that the newly synthesized compounds possess promising antimicrobial activity.

  11. Syntheses of cytotoxic novel arctigenin derivatives bearing halogen and alkyl groups on aromatic rings.

    Science.gov (United States)

    Yamauchi, Satoshi; Wukirsari, Tuti; Ochi, Yoshiaki; Nishiwaki, Hisashi; Nishi, Kosuke; Sugahara, Takuya; Akiyama, Koichi; Kishida, Taro

    2017-09-01

    The new lignano-9,9'-lactones (α,β-dibenzyl-γ-butyrolactone lignans), which showed the higher cytotoxicity than arctigenin, were synthesized. The well-known cytotoxic arctigenin showed activity against HL-60 cells (EC 50 =12μM), however, it was inactive against HeLa cells (EC 50 >100μM). The synthesized (3,4-dichloro, 2'-butoxy)-derivative 55 and (3,4-dichloro, 4'-butyl)-derivative 66 bearing the lignano-9,9'-lactone structures showed the EC 50 values of 10μM and 9.4μM against HL-60 cells, respectively. Against HeLa cells, the EC 50 value of the derivative 66 was 27μM. By comparing the activities with the corresponding 9,9'-epoxy structure (tetrahydrofuran compounds), the importance of the lactone structure of 55 and 66 for the higher activities was shown. The substituents on the aromatic ring of the lignano-9,9'-lactones affected the cytotoxicity level, observing more than 10-fold difference. Copyright © 2017. Published by Elsevier Ltd.

  12. Syntheses and characterization of non-bisphosphonate quinoline derivatives as new FPPS inhibitors.

    Science.gov (United States)

    Liu, Jinggong; Liu, Weilin; Ge, Hu; Gao, Jinbo; He, Qingqing; Su, Lijuan; Xu, Jun; Gu, Lian-Quan; Huang, Zhi-shu; Li, Ding

    2014-03-01

    Farnesyl pyrophosphate synthase (FPPS) is a key regulatory enzyme in the biosynthesis of cholesterol and in the post-translational modification of signaling proteins. It has been reported that non-bisphosphonate FPPS inhibitors targeting its allosteric binding pocket are potentially important for the development of promising anti-cancer drugs. The following methods were used: organic syntheses of non-bisphosphonate quinoline derivatives, enzyme inhibition studies, fluorescence titration assays, synergistic effect studies of quinoline derivatives with zoledronate, ITC studies for the binding of FPPS with quinoline derivatives, NMR-based HAP binding assays, molecular modeling studies, fluorescence imaging assay and MTT assays. We report our syntheses of a series of quinoline derivatives as new FPPS inhibitors possibly targeting the allosteric site of the enzyme. Compound 6b showed potent inhibition to FPPS without significant hydroxyapatite binding affinity. The compound showed synergistic inhibitory effect with active-site inhibitor zoledronate. ITC experiment confirmed the good binding effect of compound 6b to FPPS, and further indicated the binding ratio of 1:1. Molecular modeling studies showed that 6b could possibly bind to the allosteric binding pocket of the enzyme. The fluorescence microscopy indicated that these compounds could get into cancer cells. Our results showed that quinoline derivative 6b could become a new lead compound for further optimization for cancer treatment. The traditional FPPS active-site inhibitors bisphosphonates show poor membrane permeability to tumor cells, due to their strong polarity. The development of new non-bisphosphonate FPPS inhibitors with good cell membrane permeability is potentially important. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Mould Growth and Aflatoxin Accumulation Affected by Newly Synthesized Derivative of Coumarine Treatment of Maize Hybrid

    OpenAIRE

    Lejla Duraković; Mihaela Blažinkov; Branka Šeol; Alma Tudić; Frane Delaš; Marijan Bošnjak; Sanja Sikora; Andrea Skelin; Katarina Huić-Babić; Zijad Duraković

    2014-01-01

    The effect of newly synthesized derivative of 11-hydroxy-7-imino-7H-7a, 12-diazabenzo/α/anthracen-6-one, on growth and aflatoxin B1 and G1 (AFB1 and AFG1) accumulation by toxigenic mould Aspergillus fl avus ATCC 26949 was studied on a solid substrate (maize grains) to determine the possible use of this compound as a mean of controlling aflatoxin accumulation. Experiments were carried out in a stationary culture at temperature of 28oC during 21 days. The growth of mould was monitored by ...

  14. First Total Syntheses and Antimicrobial Evaluation of Penicimonoterpene, a Marine-Derived Monoterpenoid, and Its Various Derivatives

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    Jian-Chun Zhao

    2014-06-01

    Full Text Available The first total synthesis of marine-derived penicimonoterpene (±-1 has been achieved in four steps from 6-methylhept-5-en-2-one using a Reformatsky reaction as the key step to construct the basic carbon skeleton. A total of 24 new derivatives of 1 have also been designed and synthesized. Their structures were characterized by analysis of their 1H NMR, 13C NMR and HRESIMS data. Some of them showed significant antibacterial activity against Aeromonas hydrophila, Escherichia coli, Micrococcus luteus, Staphylococcus aureus, Vibrio anguillarum, V. harveyi and/or V. parahaemolyticus, and some showed activity against plant-pathogenic fungi (Alternaria brassicae, Colletotrichum gloeosporioides and/or Fusarium graminearum. Some of the derivatives exhibited antimicrobial MIC values ranging from 0.25 to 4 μg/mL, which were stronger than those of the positive control. Notably, Compounds 3b and 10 showed extremely high selectively against plant-pathogenic fungus F. graminearum (MIC 0.25 μg/mL and pathogenic bacteria E. coli (MIC 1 μg/mL, implying their potential as antimicrobial agents. SAR analysis of 1 and its derivatives indicated that modification of the carbon-carbon double bond at C-6/7, of groups on the allylic methylene unit and of the carbonyl group at C-1, effectively enhanced the antimicrobial activity.

  15. Release profile of synthesized coumarin derivatives as a novel antibacterial agent from glass ionomer cement (GIC)

    Science.gov (United States)

    Rahman, Fatimah Suhaily Abdul; Osman, Hasnah; Mohamad, Dasmawati

    2017-12-01

    Glass ionomer cements (GIC) are widely used as dental restorative materials due to their aesthetics features and fluoride content. However, a capability of fluoride content in GIC to inhibit bacteria growth in an oral environment was insufficient for a long term which may lead to secondary caries. Therefore, two types of synthesized coumarin derivatives were incorporated with GIC to act as new antibacterial agent. However prior to the antibacterial evaluation, this study investigated the release profile of GIC incorporated with 3-Acetylcoumarin (GIC-1) and hydrazinyl thiosemicarbazide of coumarin derivatives (GIC-2) at three different concentrations of 0.5, 1.0 and 1.5 wt% up to 30 days. At early incubation period, GIC-1 revealed a higher release profile at 0.5 % fabrication that reached almost 45 % of cumulative release for 8 hours observational. Meanwhile, a slightly different output was obtained for GIC-2 in which 1.0 % fabrication of coumarin gave a better release in the initial hour. However, the pattern was replaced by 0.5 % substitution after 4 hours incubation time. A substitution of 1.5 % coumarin seems to be low in releasing activity for all materials. Conversely, in a longer period 1.0 % fabrication was discovered to be the highest coumarin release among others fabrications for both materials. Filler particle size and porosity of the materials were considered to be the main factor that may affect the coumarin release. Nonetheless, both synthesized coumarin derivatives can be incorporated with GIC as their release profile look very promising. Ultimately, the coumarin derivatives could improve the properties of GIC.

  16. Novel topoisomerase I inhibitors. Syntheses and biological evaluation of phosphorus substituted quinoline derivates with antiproliferative activity.

    Science.gov (United States)

    Alonso, Concepción; Fuertes, María; Martín-Encinas, Endika; Selas, Asier; Rubiales, Gloria; Tesauro, Cinzia; Knudssen, Birgitta K; Palacios, Francisco

    2018-02-22

    This work describes the synthesis of 1,2,3,4-tetrahydroquinolinylphosphine oxides, phosphanes and phosphine sulfides as well as that of quinolinylphosphine oxides and phosphine sulfides, which were synthesized in good to high overall yield. The synthetic route involves a multicomponent reaction of (2-phosphine-oxide)-, 2-phosphine- or (2-phosphine-sulfide)-aniline, aldehydes and olefins and allows the selective generation of two stereogenic centres in a short, efficient and reliable synthesis. The selective dehydrogenation of 1,2,3,4-tetrahydroquinolinylphosphine oxides and phosphine sulfides leads to the formation of corresponding phosphorus substituted quinolines. Some of the products which were prepared showed excellent activity as topoisomerase I (Top1) inhibitors. In addition, prolonged effect of the most potent compounds is maintained with the same intensity even after 3 min of the beginning of the enzymatic reaction. The cytotoxic effect on cell lines derived from human lung adenocarcinoma (A549), human ovarian carcinoma (SKOV03) and human embryonic kidney (HEK293) was also screened. 1,2,3,4-Tetrahydroquinolinylphosphine oxide 6g with an IC 50 value of 0.25 ± 0.03 μM showed excellent activity against the A549 cell line in vitro, while 1,2,3,4-tetrahydroquinolinylphosphane 9c with an IC 50 value of 0.08 ± 0.01 μM and 1,2,3,4-tetrahydroquinolinylphosphine sulfide derivative 10f with an IC 50 value of 0.03 ± 0.04 μM are more active against the A549 cell line. Moreover, selectivity towards cancer cell (A549) over non-malignant cells (MRC5) has been observed. According to their structure, they may be excellent antiproliferative candidates. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  17. Combined spectroscopic, DFT, TD-DFT and MD study of newly synthesized thiourea derivative

    Science.gov (United States)

    Menon, Vidya V.; Sheena Mary, Y.; Shyma Mary, Y.; Panicker, C. Yohannan; Bielenica, Anna; Armaković, Stevan; Armaković, Sanja J.; Van Alsenoy, Christian

    2018-03-01

    A novel thiourea derivative, 1-(3-bromophenyl)-3-[3-(trifluoromethyl)phenyl]thiourea (ANF-22) is synthesized and characterized by FTIR, FT-Raman and NMR spectroscopy experimentally and theoretically. A detailed conformational analysis of the title molecule has been conducted in order to locate the lowest energy geometry, which was further subjected to the detailed investigation of spectroscopic, reactive, degradation and docking studies by density functional theory (DFT) calculations and molecular dynamics (MD) simulations. Time dependent DFT (TD-DFT) calculations have been used also in order to simulate UV spectra and investigate charge transfer within molecule. Natural bond orbital analysis has been performed analyzing the charge delocalization and using HOMO and LUMO energies the electronic properties are analyzed. Molecular electrostatic potential map is used for the quantitative measurement of active sites in the molecule. In order to determine the locations possibly prone to electrophilic attacks we have calculated average local ionization energies and mapped them to the electron density surface. Further insight into the local reactivity properties have been obtained by calculation of Fukui functions, also mapped to the electron density surface. Possible degradation properties by the autoxidation mechanism have been assessed by calculations of bond dissociation energies for hydrogen abstraction. Atoms of title molecule with significant interactions with water molecules have been determined by calculations of radial distribution functions. The title compound can be a lead compound for developing new analgesic drug.

  18. Syntheses and properties of several metastable and stable hydrides derived from intermetallic compounds under high hydrogen pressure

    Energy Technology Data Exchange (ETDEWEB)

    Filipek, S.M., E-mail: sfilipek@unipress.waw.pl [Institute of High Pressure Physics PAS, ul. Sokolowska 29, 01-142 Warsaw (Poland); Paul-Boncour, V. [ICMPE-CMTR, CNRS-UPEC, 2-8 rue Henri Dunant, 94320 Thiais (France); Liu, R.S. [Department of Chemistry, National Taiwan University, Taipei 106, Taiwan (China); Jacob, I. [Unit Nuclear Eng., Ben Gurion University of the Negev, Beer-Sheva (Israel); Tsutaoka, T. [Dept. of Sci. Educ., Grad. School of Educ., Hiroshima University, Hiroshima (Japan); Budziak, A. [Institute of Nuclear Physics PAS, 31-342 Kraków (Poland); Morawski, A. [Institute of High Pressure Physics PAS, ul. Sokolowska 29, 01-142 Warsaw (Poland); Sugiura, H. [Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027 (Japan); Zachariasz, P. [Institute of Electron Technology Cracow Division, ul. Zablocie 39, 30-701 Krakow (Poland); Dybko, K. [Institute of Physics, PAS, 02-668 Warsaw (Poland); Diduszko, R. [Tele and Radio Research Institute, ul. Ratuszowa 11, Warsaw (Poland)

    2016-12-01

    Brief summary of our former work on high hydrogen pressure syntheses of novel hydrides and studies of their properties is supplemented with new results. Syntheses and properties of a number of hydrides (unstable, metastable or stable in ambient conditions) derived under high hydrogen pressure from intermetallic compounds, like MeT{sub 2}, MeNi{sub 5}, Me{sub 7}T{sub 3}, Y{sub 6}Mn{sub 23} and YMn{sub 12} (where Me = zirconium, yttrium or rare earth; T = transition metal) are presented. Stabilization of ZrFe{sub 2}H{sub 4} due to surface phenomena was revealed. Unusual role of manganese in hydride forming processes is pointed out. Hydrogen induced phase transitions, suppression of magnetism, antiferromagnetic-ferromagnetic and metal-insulator or semimetal-metal transitions are described. Equations of state (EOS) of hydrides submitted to hydrostatic pressures up to 30 GPa are presented and discussed.

  19. Syntheses of some Bunte's salts, isothiourea derivatives and thioethers, potential radioprotective agents. Part 40

    International Nuclear Information System (INIS)

    Tulecki, J.; Kalinowska Torz, J.; Musial, E.; Nacewicz-Anjedani, H.; Senczuk, L.; Skwarski, D.; Sobolewski, H.

    1977-01-01

    By reacting respective halogen-derivatives with sodium or potassium thiosulphate there were obtained sodium or potassium salts of S-thiosulphates of 1-ureidocarbonyl-1-butyl, 3,4-dihydroxyphenacyl, carbophenoxymethyl, 2-hydroxyphenacyl, /N-(4-iodophenyl) carbamyl/methyl, /N-(4-iodophenyl) carbamyl/ethyl, /N-(2-iodophenyl) carbamyl/-methyl, /N-(2-iodophenyl) carbamyl/ethyl, /N-(6-carbomethoxybenzothiazolyl-2)-carbamyl/methyl, (2,4-dihydroxy-6-methylpyrimidyl-5)-methyl and (2,4-dihydroxypyrimidyl-5)-methyl. Reactions of thiourea with respective halogen-derivatives yielded hydrochlorides of 1-methyl-02-amidinothiomethylbenzimidazole, 1-ethyl-2-amidinothiomethylbenzimidazole, S-/N-(2-iodophenyl) carbamylethyl/ isothiourea, 5-amidinothiomethyl-6-methyl-2,4-dihydroxypyrimide and 5-amidinothiomethyl-2,4-dihydroxypyrimidine. Reactions of 4-chloroquinoline N-oxide with respective mercaptanes afforded thioether derivatives of quinoline N-oxide: 4-(p-chlorophenylthio)-4-(t-butylthio)-, 4-(3-naphtylthio)-, 4-(3-naphtylaminoacetylthio), 4-(benzimidazolythio)-, 4-(benzothiazolylthio) - and 4-benzoxalylthio. (author)

  20. Antibacterial Activity of Coumarine Derivatives Synthesized from 4-Chloro-chromen-2-one. The Comparison with Standard Drug.

    OpenAIRE

    Aziz Behrami

    2014-01-01

    This work reports the synthesis of some new derivatives from 4-Chloro-chromen-2-one and describe the results of antibacterial activity of purified compounds. Compounds 4-Butylamino-chromen-2-one (1a) , 4-Butylamino-2-oxo-2H-chromene-3-sulfonyl chloride (2a) , 4-Butylamino-2-oxo-2H-chromene-3-sulfonic acid (2-hydroxy-phenyl)-amide (3a), 4-Butylamino-5-ethyl-2-oxo-7-(N'-phenyl-hydrazino)-2H-chromene-3-sulfonic acid (2-hydroxy-phenyl)-amide (4a) , have been synthesized and characterized using me...

  1. Syntheses of Azo-Imine Derivatives from Vanillin as an Acid Base Indicator

    Directory of Open Access Journals (Sweden)

    Bambang Purwono

    2013-05-01

    Full Text Available Preparations of azo, imine and azo-imine derivatives from vanillin as an indicator of acid-base titration have been carried out. The azo derivative of 4-hydroxy-3-methoxy-5-(phenylazobenzaldehyde 2 was produced by diazotitation reaction of vanillin in 37.04% yield. The azo product was then refluxed with aniline in ethanol to yield azo-imine derivatives, 2-methoxy-6-(phenylazo-4-((phenyliminomethylphenol 1 in 82.21% yield. The imine derivative, 2-methoxy-4-((phenyliminomethyl-phenol 3 was obtained by refluxing of vanillin and aniline mixture in ethanol solvent and produced 82.17% yield. The imine product was then reacted with benzenediazonium chloride salt. However, the products indicated hydrolyzed product of 4-hydroxy-3-methoxy-5-(phenylazobenzaldehyde 2 in 22.15% yield. The 2-methoxy-4-((phenyliminomethylphenol 2 could be used as an indicator for titration of NaOH by H2C2O4 with maximum concentration of H2C2O4 0.1 M while the target compound 1 could be used as titration indicator for titration of NaOH with H2C2O4 with same result using phenolphthalein indicator.

  2. Syntheses, structures and luminescent properties of lanthanide coordination polymers assembled from imidazophenanthroline derivative and oxalate ligands

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Hui; Sun, Xiao-Xia; Hu, Huai-Ming, E-mail: ChemHu1@NWU.EDU.CN; An, Ran; Yang, Meng-Lin; Xue, Ganglin

    2017-01-15

    Nine new lanthanide coordination polymers, namely, [Ln(Hsfpip)(ox){sub 0.5}(H{sub 2}O)]{sub n}·2n(H{sub 2}O) ((Ln=Eu (1), Tb (2), Dy (3), Ho (4), Er (5), Yb (6), Y(7)), [Ln(H{sub 2}sfpip)(ox)(H{sub 2}O){sub 4}]{sub n}·2n(H{sub 2}O) (Ln=Nd (8) Sm (9)), [H{sub 2}ox=oxalic acid, H{sub 3}sfpip=2-(2,4-disulfophenyl)imidazo(4,5-f)(1,10)-phenanthroline] have been synthesized under hydrothermal conditions and characterized by IR spectra, elemental analysis, powder X-ray diffraction and single crystal X-ray diffraction. When sodium oxalate is added, the reactions of lanthanide ions with H{sub 3}sfpip resulted in two types of structures. Compounds 1–7 are obtained at pH 5.0 and exhibit 3D tfz-d networks with ox{sup 2−} anions as linkers to bridge the adjacent layers. Compounds 8–9 are obtained at pH 2.0, and display a 1D chain which is further extended to a 3D supramolecular framework through intermolecular hydrogen bonds and π-π interactions. The structural variation from compounds 1–7 to 8–9 can attribute to the pH effect on construction of lanthanide coordination polymers. Moreover, the thermal stabilities and luminescence properties of 1–9 were also investigated. - Graphical abstract: Nine new lanthanide coordination polymers have been synthesized under hydrothermal conditions. Compounds 1–7 exhibit a 3D tfz-d network. Compounds 8–9 display a 1D chain structure. The structural variation from compounds 1–7 to 8–9 can attribute to the pH effect on construction of lanthanide coordination polymers. - Highlights: • Nine lanthanide coordination polymers were prepared under hydrothermal conditions. • Their crystal structures have been determined. • The luminescence and thermal stabilities were studied in the solid state.

  3. Derived Manding in Children with Autism: Synthesizing Skinner's Verbal Behavior with Relational Frame Theory

    Science.gov (United States)

    Murphy, Carol; Barnes-Holmes, Dermot; Barnes-Holmes, Yvonne

    2005-01-01

    Mand functions for two stimuli (A1 and A2) were trained for 3 children with autism and were then incorporated into two related conditional discriminations (A1-B1/A2 -B2 and B1-C1/B2-C2). Tests were conducted to probe for a derived transfer of mand response functions from Al and A2 to C1 and C2, respectively. When 1 participant failed to…

  4. Chemical Architecture and Applications of Nucleic Acid Derivatives Containing 1,2,3-Triazole Functionalities Synthesized via Click Chemistry

    Directory of Open Access Journals (Sweden)

    Wei Gong

    2012-10-01

    Full Text Available There is considerable attention directed at chemically modifying nucleic acids with robust functional groups in order to alter their properties. Since the breakthrough of copper-assisted azide-alkyne cycloadditions (CuAAC, there have been several reports describing the synthesis and properties of novel triazole-modified nucleic acid derivatives for potential downstream DNA- and RNA-based applications. This review will focus on highlighting representative novel nucleic acid molecular structures that have been synthesized via the “click” azide-alkyne cycloaddition. Many of these derivatives show compatibility for various applications that involve enzymatic transformation, nucleic acid hybridization, molecular tagging and purification, and gene silencing. The details of these applications are discussed. In conclusion, the future of nucleic acid analogues functionalized with triazoles is promising.

  5. Gamma irradiation effect on polymers derived of pyrrole synthesized by plasma

    International Nuclear Information System (INIS)

    Lopez G, O. G.

    2013-01-01

    This work studies the effect of gamma irradiation at doses of 50, 100, 200, 400 and 800 kGy on polymers obtained from pyrrole synthesized by plasma. The evolution of the structure was studied by Fourier transform infrared spectroscopy (Ftir) and X-ray photoelectron spectroscopy (XPS). The Ftir spectra show that poly pyrroles have N-H, C-H, C=O, triple and consecutive double bonds in their structure. The irradiated polymers show the same chemical groups in their structure without significant changes. Nevertheless, a more detailed analysis by XPS allows the identification of superficial chemical states, such as: C=CH-C, C=CC-C, C-NH-C, C-NC-C, etc., and shows that most of these states are present in all polymers but with different participation. One possible mechanism indicates that as the irradiation dose increases, dehydrogenation processes are performed increasing fragmentation, crosslinking and formation of multiple bonds. The fragmentation and thermal degradation were studied by thermogravimetric analysis, indicating that the loss of moisture and light compounds formed during gamma irradiation occurs in the firsts 100 grades C. The main degradation of all polymers occurs from 150 to 700 grades C, suggesting that the thermal stability is independent of the irradiation dose in the interval studied. Morphology was studied using scanning electron microscopy techniques. Before irradiation, the polymer presented a uniform and practically smooth surface, however, after gamma irradiation, the applied energy increased roughness and macro fragmentation. The roughness and functional groups on the surface reduced the contact angle with water as the irradiation dose increased. However, the polymers are hydrophilic, because for all doses that contact angle is smaller than 90 grades C. Electrical conductivity was calculated respect to temperature in the interval from 25 to 100 grades C. Conductivity increases with temperature and is slightly greater in the irradiated polymers

  6. Copper extraction by fatty hydroxamic acids derivatives synthesized based on palm kernel oil.

    Science.gov (United States)

    Haron, Jelas; Jahangirian, Hossein; Silong, Sidik; Yusof, Nor Azah; Kassim, Anuar; Moghaddam, Roshanak Rafiee; Peyda, Mazyar; Abdollahi, Yadollah; Amin, Jamileh; Gharayebi, Yadollah

    2012-01-01

    Fatty hydroxamic acids derivatives based on palm kernel oil which are phenyl fatty hydroxamic acids (PFHAs), methyl fatty hydroxamic acids (MFHAs), isopropyl fatty hydroxamic acids (IPFHAs) and benzyl fatty hydroxamic acids (BFHAs) were applied as chelating agent for copper liquid-liquid extraction. The extraction of copper from aqueous solution by MFHAs, PFHAs, BFHAs or IPFHAs were carried out in hexane as an organic phase through the formation of copper methyl fatty hydroxamate (Cu-MFHs), copper phenyl fatty hydroxamate (Cu-PFHs), copper benzyl fatty hydroxamate (Cu-BFHs) and copper isopropyl fatty hydroxamate (Cu-IPFHs). The results showed that the fatty hydroxamic acid derivatives could extract copper at pH 6.2 effectively with high percentage of extraction (the percentages of copper extraction by MFHAs, PFHAs, IPFHs and BFHAs were found to be 99.3, 87.5, 82.3 and 90.2%, respectively). The extracted copper could be quantitatively stripped back into sulphuric acid (3M) aqueous solution. The obtained results showed that the copper recovery percentages from Cu-MFHs, Cu-PFHs, Cu-BFHs and Cu-IPFHs are 99.1, 99.4, 99.6 and 99.9 respectively. The copper extraction was not affected by the presence of a large amount of Mg (II), Ni (II), Al (III), Mn (II) and Co (II) ions in the aqueous solution.

  7. Antiobesity, antioxidant and cytotoxicity activities of newly synthesized chalcone derivatives and their metal complexes.

    Science.gov (United States)

    El Sayed Aly, Mohamed Ramadan; Abd El Razek Fodah, Hamadah Hamadah; Saleh, Sherif Yousef

    2014-04-09

    Four sets of rationally designed chalcones were prepared for evaluation of their antiobesity, antioxidant and cytotoxicity activities. These sets include nine oleoyl chalcones as mimics of oleoyl estrone, three monohydroxy chalcones (chalcone ligands), Schiff base-derived chalcones and four copper as well as zinc complexes. Oleoyl chalcones 4d, 4e and particularly 6a as an isosteric isomer of oleoyl estrone, were as active as Orlistat on weight loss and related metabolic parameters using male SD rats in vivo. Chalcone ligands 10a-c and Schiff base-derived chalcones 11 and 14a,b were weakly antioxidants, while, the copper and zinc complexes 15a-d were good antioxidants with zinc chelates 15b,d being more active than their copper analogues 15a,cin vitro. Compounds 10c and 14a showed good cytotoxicity activities as Doxorubicin against PC3 cancer cell line in vitro, while, the copper complex 15c showed promising activity with IC₅₀ value of 5.95 μM. The estimated IC₅₀ value for Doxorubicin was 8.7 μM. Chalcones 14a,b are bifunctional probes for potential investigations in cancer diagnosis and radiotherapy by complexation with Gd(3+) or metal radioisotopes followed by posttranslation of Shiga toxin B-subunits that target globotriosyl ceramide expressing cancer cells. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  8. Cytotoxicity and Radiosensitising Activity of Synthesized Dinitrophenyl Derivatives of 5-Fluorouracil

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    Khosrou Abdi

    2012-07-01

    Full Text Available Background and the purpose of the study: Dual functional agents in which nitroaromatic or nitroheterocyclic compounds are attached through a linker unit to mustards and aziridines have shown higher cytotoxicities than the corresponding counterparts to both aerobic and hypoxic cells and enhanced radiosensitizing activity. In thepresent investigation cytotoxicity and radiosensitizing activity of 2,4-dinitrobenzyl, 2,4-dinitrobenzoyl, and 2,4-dinitrophenacetyl derivatives of 5-fluorouracil which was assumed to release cytotoxic active quinone methidide,and 5-fluorouracil under hypoxic conditions on HT-29 cell line under both aerobic and hypoxic conditions wasinvestigated.Methods: 5-fluorouracil derivative X-XIII were prepared by the reaction of the corresponding di-nitro substitutedbenzyl, benzoyl and phenacetyl halides with 5-fluorouracil protected at N-1 with di-t-butoxydicarbonate (BOC in dimethyl formamide (DMF in the presence of the potassium carbonate followed by hydrolysis of the blocking,group by potassium carbonate in methanol. Cytotoxicity of fluorouracil VIII and tested compounds X-XIII against HT-29cell line under both aerobic and hypoxic conditions after 48 hrs incubation were measured by determination of the percent of the survival cells using 3-(4,5-Dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay and percent of the dead cells using propidium iodide(PI-digitonine assay and results were used to calculate the corresponding IC50 values. Radiosensitization experiments were carried out by irradiation of the incubations with a 60Co source and clonogenic assay was performed to determine the cell viabilities following treatment with the tested compounds and/or radiation. Sensitization Enhancement Ratio (SER of each tested compound was obtained from the radiation survival curves in the absence and presence of each sensitizer for 37% survival respectively.Results and major conclusion: Findings of the present study showed that

  9. Cytotoxicity and radiosensitising activity of synthesized dinitrophenyl derivatives of 5-fluorouracil

    Directory of Open Access Journals (Sweden)

    Khoshayand Mohammad

    2012-07-01

    Full Text Available Abstract Background and the purpose of the study Dual functional agents in which nitroaromatic or nitroheterocyclic compounds are attached through a linker unit to mustards and aziridines have shown higher cytotoxicities than the corresponding counterparts to both aerobic and hypoxic cells and enhanced radiosensitizing activity. In the present investigation cytotoxicity and radiosensitizing activity of 2,4-dinitrobenzyl, 2,4-dinitrobenzoyl, and 2,4-dinitrophenacetyl derivatives of 5-fluorouracil which was assumed to release cytotoxic active quinone methidide and 5-fluorouracil under hypoxic conditions on HT-29 cell line under both aerobic and hypoxic conditions was investigated. Methods 5-fluorouracil derivative X-XIII were prepared by the reaction of the corresponding di-nitro substituted benzyl, benzoyl and phenacetyl halides with 5-fluorouracil protected at N-1 with di-t-butoxydicarbonate (BOC in dimethyl formamide (DMF in the presence of the potassium carbonate followed by hydrolysis of the blocking group by potassium carbonate in methanol. Cytotoxicity of fluorouracil VIII and tested compounds X-XIII against HT-29 cell line under both aerobic and hypoxic conditions after 48 hrs incubation were measured by determination of the percent of the survival cells using 3-(4,5-Dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay and percent of the dead cells using propidium iodide(PI-digitonine assay and results were used to calculate the corresponding IC50 values. Radiosensitization experiments were carried out by irradiation of the incubations with a 60Co source and clonogenic assay was performed to determine the cell viabilities following treatment with the tested compounds and/or radiation. Sensitization Enhancement Ratio (SER of each tested compound was obtained from the radiation survival curves in the absence and presence of each sensitizer for 37% survival respectively. Results and major conclusion Findings of the present study

  10. Electronic and optical properties of new synthesized TTF-based azine derivatives - Experimental and theoretical study

    Science.gov (United States)

    Ayadi, Awatef; Mydlova, Lucia; Zouari, Nabil; Makowska-Janusik, Malgorzata; Sahraoui, Bouchta; El-Ghayoury, Abdelkrim

    2016-06-01

    The synthesis and detailed characterization of two tetrathiafulvalene-appended azine derivatives, namely 2-([2,2‧-bi(1,3-dithiolylidene)]-4-yl)-6-((2,4-dimethylphenyl)hydrazono) methyl)pyridine (L1) and 5-([2,2‧-bi(1,3-dithiolylidene)]-4-yl)-2-((2,4-dimethylphenyl)hydrazono) methyl)pyridine (L2) are described. The crystal structure of ligand L2 indicates that the mentioned molecule is completely planar with the presence of a strong intramolecular N1sbnd H1⋯N3 hydrogen bonding. The quantum chemical calculations show that the intermolecular interaction in crystal structure does not affect the HOMO and LUMO orbitals present in isolated molecule. The optical properties of these ligands indicate the presence of intramolecular charge transfer band in the case of ligand L2 while the electrochemical behavior of the two compounds indicates that they are valuable candidates for the construction of crystalline radical cation salts.

  11. Silver ion recognition using potentiometric sensor based on recently synthesized isoquinoline-1,3-dione derivatives

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    AJAR KAMAL

    2012-08-01

    Full Text Available The four derivatives of isoquinoline-1,3-dione based on β-lactum (I-IV, have been explored as neutral ionophores for preparing poly(vinylchloride based polymeric membrane electrodes (PME selective to silver(I ions. The addition of sodium tetraphenylborate (NaTPB and dioctylsebacate (DOS as a plasticizer was found to improve the performance of ion selective electrodes. The best performance was obtained with PME-1 based on ionophore I having composition: ionophore (9.2 mg, PVC (100.1 mg, DOS (201.1 mg and NaTPB (1.5 mg in 5 mL tetrahydrofuran. The electrode response was linear with Nernstian slope of 58.44 mV/decade in the concentration range of 1.0 x 10-1 M to 5.0 x 10-6 M and detection limit of 5.83 x 10-6 M. It performs satisfactorily over wide pH range of 1.0-5.5. The proposed sensor can be used over a period of more than three months without any significant drift in potential and shows good selectivity to silver(I ion over a number of cations especially with no interference of mercury(II ions. Sharp end point was obtained when the sensor was used as an indicator electrode for the potentiometric titration of silver(I ions with chloride ions and therefore this electrode (PME-1 could be used for quantitative determination of silver(I ion in synthetic water, silver foil and dental amalgam samples.

  12. Study of antimicrobial, analgesic wound healing and antioxidant activities of some newly synthesized oxychinolin derivatives and their characterization

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    Jyotirmaya Sahoo

    2015-09-01

    Full Text Available A series of aryl and heteroaryl substituted oxychinolin derivatives have been synthesized and spectral characterizations have been conducted with different modern analytical techniques. The antimicrobial activities of the novel synthesized oxychinolin analogs against different microbial strains have been screened by agar diffusion method. The compounds 4g and 4h were observed with significant antibacterial activity in comparison to reference antibiotic (ampicillin against most of the bacterial pathogens. Compounds 4-((8-hydroxyquinolin-5-yl diazenyl-N-(5-methyl isoxazol-3-yl benzene sulfonamide (4c, 4-((8-hydroxyquinolin-5-yl diazenyl-1, 5-dimethyl-2-phenyl-1H-pyrazol-3(2H-one (4g and 2-((8-hydroxyquinolin-5-yldiazenyl benzoic acid (4h showed zone of inhibition at MIC level 31.25 µg mL−1 against most of the organisms. The compounds 4g and 4h are observed with significant wound healing, analgesic and potential antioxidant activity.

  13. Palladium-catalyzed asymmetric allylic substitution of 2-arylcyclohexenol derivatives: asymmetric total syntheses of (+)-crinamine, (-)-haemanthidine, and (+)-pretazettine.

    Science.gov (United States)

    Nishimata, Toyoki; Sato, Yoshihiro; Mori, Miwako

    2004-03-19

    Much interest has been shown in Amaryllidaceae alkaloids as synthetic targets due to their wide range of biological activities. Over 100 alkaloids have been isolated from members of the Amaryllidaceae family; most of them can be classified into eight skeletally homogeneous groups. We have succeeded in the first asymmetric total syntheses of the crinane-type alkaloids (+)-crinamine (1), (-)-haemanthidine (2), and (+)-pretazettine (3). The starting cyclohexenylamine 14 was obtained from allyl phosphonate 11c by palladium-catalyzed asymmetric amination in 82% yield and with 74% ee. The product was recrystallized from MeOH. Interestingly, (-)-14 with 99% ee was obtained from the mother liquor (74% recovery). Intramolecular carbonyl-ene reaction of (-)-10 proceeds in a highly stereoselective manner to give hexahydroindole derivative 9 as the sole product. In the Lewis-acid-catalyzed carbonyl-ene reaction, an interesting rearrangement product, 20, was isolated in high yield. From 9, (+)-crinamine was synthesized. Thus, the asymmetric total synthesis of (+)-crinamine was achieved in 10 steps from 11c, and the overall yield is 19%. The total synthesis of (-)-haemanthidine was also achieved from 9 by a short sequence of steps.

  14. Copper(II)-selective membrane electrode based on a recently synthesized naphthol-derivative Schiff's base

    Energy Technology Data Exchange (ETDEWEB)

    Alizadeh, N.; Ershad, S. [Dept. of Chemistry, Tarbiat Moderres Univ., Tehran (Iran); Naeimi, H.; Sharghi, H. [Dept. of Chemistry, Shiraz Univ. (Iran); Shamsipur, M. [Dept. of Chemistry, Razi Univ., Kermanshah (Iran)

    1999-11-01

    A PVC membrane electrode for copper(II) ions based on a recently synthesized naphthol-derivative Schiff's base as membrane carrier was prepared. The sensor exhibits a Nernstian response for Cu{sup 2+} ions over a wide concentration range (5.0 x 10{sup -6}-5.0 x 10{sup -2} mol/L) with a detection limit of 3.1 x 10{sup -6} mol/L (0.2 {mu}g/mL). It has a very short response time of about 5 s and can be used for 3 months without any divergence in potential. The proposed electrode revealed good selectivities over a wide variety of other cations including alkali, alkaline earth, transition and heavy metal ions and could be used in a pH range of 4.0-7.0. It was successfully applied to the direct determination and potentiometric titration of copper ion. (orig.)

  15. Discovery Strategies of Bioactive Compounds Synthesized by Nonribosomal Peptide Synthetases and Type-I Polyketide Synthases Derived from Marine Microbiomes.

    Science.gov (United States)

    Amoutzias, Grigoris D; Chaliotis, Anargyros; Mossialos, Dimitris

    2016-04-16

    Considering that 70% of our planet's surface is covered by oceans, it is likely that undiscovered biodiversity is still enormous. A large portion of marine biodiversity consists of microbiomes. They are very attractive targets of bioprospecting because they are able to produce a vast repertoire of secondary metabolites in order to adapt in diverse environments. In many cases secondary metabolites of pharmaceutical and biotechnological interest such as nonribosomal peptides (NRPs) and polyketides (PKs) are synthesized by multimodular enzymes named nonribosomal peptide synthetases (NRPSes) and type-I polyketide synthases (PKSes-I), respectively. Novel findings regarding the mechanisms underlying NRPS and PKS evolution demonstrate how microorganisms could leverage their metabolic potential. Moreover, these findings could facilitate synthetic biology approaches leading to novel bioactive compounds. Ongoing advances in bioinformatics and next-generation sequencing (NGS) technologies are driving the discovery of NRPs and PKs derived from marine microbiomes mainly through two strategies: genome-mining and metagenomics. Microbial genomes are now sequenced at an unprecedented rate and this vast quantity of biological information can be analyzed through genome mining in order to identify gene clusters encoding NRPSes and PKSes of interest. On the other hand, metagenomics is a fast-growing research field which directly studies microbial genomes and their products present in marine environments using culture-independent approaches. The aim of this review is to examine recent developments regarding discovery strategies of bioactive compounds synthesized by NRPS and type-I PKS derived from marine microbiomes and to highlight the vast diversity of NRPSes and PKSes present in marine environments by giving examples of recently discovered bioactive compounds.

  16. Discovery Strategies of Bioactive Compounds Synthesized by Nonribosomal Peptide Synthetases and Type-I Polyketide Synthases Derived from Marine Microbiomes

    Directory of Open Access Journals (Sweden)

    Grigoris D. Amoutzias

    2016-04-01

    Full Text Available Considering that 70% of our planet’s surface is covered by oceans, it is likely that undiscovered biodiversity is still enormous. A large portion of marine biodiversity consists of microbiomes. They are very attractive targets of bioprospecting because they are able to produce a vast repertoire of secondary metabolites in order to adapt in diverse environments. In many cases secondary metabolites of pharmaceutical and biotechnological interest such as nonribosomal peptides (NRPs and polyketides (PKs are synthesized by multimodular enzymes named nonribosomal peptide synthetases (NRPSes and type-I polyketide synthases (PKSes-I, respectively. Novel findings regarding the mechanisms underlying NRPS and PKS evolution demonstrate how microorganisms could leverage their metabolic potential. Moreover, these findings could facilitate synthetic biology approaches leading to novel bioactive compounds. Ongoing advances in bioinformatics and next-generation sequencing (NGS technologies are driving the discovery of NRPs and PKs derived from marine microbiomes mainly through two strategies: genome-mining and metagenomics. Microbial genomes are now sequenced at an unprecedented rate and this vast quantity of biological information can be analyzed through genome mining in order to identify gene clusters encoding NRPSes and PKSes of interest. On the other hand, metagenomics is a fast-growing research field which directly studies microbial genomes and their products present in marine environments using culture-independent approaches. The aim of this review is to examine recent developments regarding discovery strategies of bioactive compounds synthesized by NRPS and type-I PKS derived from marine microbiomes and to highlight the vast diversity of NRPSes and PKSes present in marine environments by giving examples of recently discovered bioactive compounds.

  17. In-vitro antimicrobial screening and molecular docking studies of synthesized 2-chloro-N-(4-phenylthiazol-2-ylacetamide derivatives

    Directory of Open Access Journals (Sweden)

    Rahmat Ali

    2015-01-01

    Full Text Available Introduction: Glucosamine-6-phosphate (GlcN6P synthase biosynthetic pathway has been identified as potential targets for the development of new antimicrobial agents. Aim: A series of 2-chloro-N-(42-phenylthiazol-25-ylacetamide derivatives (3a-r was synthesized and evaluated their antimicrobial activity. Materials and Methods: The 2-chloro-N-(Para substituted phenylthiazol-25-yl acetamide (2a-c were synthesized by stirring intermediates (1a-c with 2-chloroacetylchloride in dichloromethane in the presence of K2CO3. The intermediate (2a-c were further reacted with different secondary amine such as pyrrolidine, N-methyl piperazine, N-ethyl piperazine, thiomorpholine, morpholine, piperidine etc in ethanol in presence of TEA Triethylamine (TEA to get desired compounds (3a-r. Compounds were characterized by a spectroscopic technique such as Fourier transform infraredFTIR, 1 H-NMR, 13 C-NMR, and mass spectrometry. The synthesized thiazole derivatives (3a-r were screened for anti-bacterial and anti-fungal activity against Escherichia coli, Staphylococcus aureus NCTC 6571, Pseudomonas aeruginosa NCTC 10662, CandidaC. albicans (MTCC-183, AspergillusA. niger (MTCC 281 NCTC 10418 and AspergillusA. flavus (MTCC 277. Result and Conclusion: The results of anti-bacterial screening revealed that among all the screened compounds, eight compounds viz. 3b, 3c, 3d, 3e, 3i, 3j, 3k, and 3p showed moderate to good anti-bacterial and antifungal activity having minimum inhibitory concentration (MIC between 6.25- and 25 µg/ml. While compound 3d showed the most promising antibacterial activity against E. coli and S. aureus, while the compound 3j showed promising antifungal activity with MIC value 6.25 µg/ml against C. albicans, A. niger and A. flavus. In addition, all these eight potential molecules were also examined for possible binding on enzyme GlcN6Pglucosamine-6-phosphate synthase by molecular docking studies on (PDB ID 1JXA.

  18. [Syntheses and central depressant activity in mice of uracil derivatives. Studies on development of new sedative-hypnotics. II].

    Science.gov (United States)

    Tateoka, Y; Hiramura, S; Usami, N; Kimura, T; Watanabe, K; Yamamoto, I

    1992-07-01

    Fifteen kinds of uracil derivatives, which were substituted with functional groups such as benzyl (Bn), methoxymethyl (MOM), n-propyl (Pr) or allyl (A) group at the N1 and/or N3 position of uracil, were synthesized. Sedative-hypnotic activity, pentobarbital (PB)-induced sleep prolongation and acute toxicity as indices of their pharmacological activities were evaluated using mice. Spontaneous activities of mice treated with N1-benzyluracil (N1-BnU, 7), N3-benzyluracil (N3-BnU, 8), N1,N3-dibenzyluracil (DBnU, 9), N1-benzyl-N3-allyluracil (BnAU, 14) and N1-allyl-N3-benzyluracil (ABnU, 15) were measured. Ten kinds of uracil derivatives showed hypnotic activity. ED50's values of ABnU (15) and N1-propyl-N3-benzyluracil (PrBnU, 13) were 155 and 172 mg/kg, i.p., respectively. Those effects were more potent than that of barbital (179 mg/kg, i.p.) Ten kinds of uracil derivatives tested significantly prolonged the PB-induced sleeping time. N3-BnU (8) increased the spontaneous activity of mice at a dose of 80 mg/kg, i.p., while ABnU (15) depressed the spontaneous activity at a dose of 160 mg/kg, i.p. The other compounds did not show any significant effect on the spontaneous activity of mice. LD50's values of ABnU (15), PrBnU (13) and N1-methoxy-methyl-N3-benzyluracil (MOMBnU, 11) were 199, 229 and 363 mg/kg, i.p., respectively. LD50's values of the other derivatives were more than 480 mg/kg, i.p. These results indicate that the benzyl group at the N3 position of uracil is important for exhibiting sedative-hypnotic activity of uracil derivatives, and that ABnU (15) has the most potent central depressant activity among the uracil derivatives tested.

  19. Collective Syntheses of 2-(3-Methylbenzofuran-2-yl)phenol-Derived Natural Products by a Cascade [3,3]-Sigmatropic Rearrangement/Aromatization Strategy.

    Science.gov (United States)

    Tang, Yingzhan; Jiang, Chongguo; Zhang, Xinhang; Liu, Chengjun; Lin, Jingsheng; Wang, Yanshi; Du, Chuan; Peng, Xiaoshi; Li, Wei; Liu, Yongxiang; Cheng, Maosheng

    2017-10-20

    A cascade [3,3]-sigmatropic rearrangement/aromatization strategy to the synthesis of 2-(3-methylbenzofuran-2-yl)phenol derivatives was developed and applied to the collective syntheses of seven 2-arylbenzofuran-containing natural products, namely glycybenzofuran, glycyuralin E, lespedezol A 1 , puerariafuran, 7,2',4'-trihydroxy-3-benzofurancarboxylic acid, coumestrol, and 4'-O-methylcoumestrol. Among them, the total syntheses of glycybenzofuran, glycyuralin E, puerariafuran, 7,2',4'-trihydroxy-3-benzofurancarboxylic acid, and 4'-O-methylcoumestrol were reported for the first time. The practicality of this novel strategy in preparation of the key intermediates was demonstrated by performing the reaction on gram scale and by synthesizing a series of natural products with 2-(3-methylbenzofuran-2-yl)phenol scaffolds in a common strategy.

  20. Microwave-Assisted Syntheses of Bioactive Seven-Membered, Macro-Sized Heterocycles and Their Fused Derivatives

    Directory of Open Access Journals (Sweden)

    Mohsine Driowya

    2016-08-01

    Full Text Available This review describes the recent advances in the microwave-assisted synthesis of 7-membered and larger heterocyclic compounds. Several types of reaction for the cyclization step are discussed: Ring Closing Metathesis (RCM, Heck and Sonogashira reactions, Suzuki-Miyaura cross-coupling, dipolar cycloadditions, multi-component reactions (Ugi, Passerini, etc. Green syntheses and solvent-free procedures have been introduced whenever possible. The syntheses discussed herein have been selected to illustrate the huge potential of microwave in the synthesis of highly functionalized molecules with potential therapeutic applications, in high yields, enhanced reaction rates and increased chemoselectivity, compared to conventional methods. More than 100 references from the recent literature are listed in this review.

  1. Effect of synthesized cyclohexanol derivatives using L-menthol as a lead compound on the percutaneous absorption of ketoprofen.

    Science.gov (United States)

    Obata, Y; Sato, H; Li, C J; Takayama, K; Higashiyama, K; Nagai, T; Isowa, K

    2000-04-05

    L-Menthol was selected as a lead compound to synthesize new candidates for percutaneous absorption enhancers. In a previous study, O-ethylmenthol (MET) was the most effective compound and caused relatively little skin irritation. To develop more effective compounds, mono- or disubstitute groups of cyclohexane with an O-ethyl group were synthesized. Some 35 compounds were synthesized and evaluated for their promoting activity and effect on skin. An in vivo percutaneous absorption study was performed using rats with hydrogel containing ketoprofen and each of the synthesized compounds. The plasma concentration of ketoprofen was determined after the application of hydrogel to the abdominal area of rats. The apparent penetration rate (R(p)) was estimated based on the pharmacokinetic model with a constant rate of penetration through the skin after the lag time. The 2-compartment model was applied to the data obtained from the iv administration. As an index to evaluate the promoting activity of each enhancer, an enhancement factor (E(f)) was defined as follows: E(f) = R(p) (with enhancer)/R(p) (without enhancer). Irritation to skin was pathologically evaluated. The treated area of rat abdominal skin was excised after the in vivo experiment using total irritation score (TIS). The compound having a C-3 positioned iso-butyl group on the chemical structure was the most effective and caused relatively little irritation among mono-substituted compounds. In the case of di-substituted compounds, all had the same effect as or a stronger effect than MET. Furthermore, the promoting activity almost corresponded to irritation. To estimate log P, one of the physicochemical properties of molecules, a computer program 'CAChe' was employed. The log P was calculated using the atom typing scheme. Multiple regression analysis revealed that the relations between E(f) or TIS and log P were parabolic. It was suggested that the optimum logP value reflects the promoting activity to enhance

  2. Syntheses of planar 1,5,2,4,6,8-dithiotetrazocine derivatives and thermodynamic study on intermolecular charge transfer for developing efficient organic solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Chao-Zhi, E-mail: zhangchaozhi@nuist.edu.cn [Department of Chemistry, Nanjing University of Information Science & Technology, Nanjing 210044 (China); Shen, Dan [Department of Chemistry, Nanjing University of Information Science & Technology, Nanjing 210044 (China); Yuan, Yang [Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Nanjing University of Information Science & Technology, Nanjing 210044 (China); Song, Ming-Xia; Li, Shi-Juan [Department of Chemistry, Nanjing University of Information Science & Technology, Nanjing 210044 (China); Cao, Hui, E-mail: yccaoh@hotmail.com [Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Nanjing University of Information Science & Technology, Nanjing 210044 (China)

    2016-07-01

    A series of planar 1,5,2,4,6,8-dithiotetrazocine derivatives were synthesized for study on charge transfer at donor/acceptor interface. The fluorescence quenching spectra, and the highest occupied molecular orbital (−6.10 ∼ −6.25 eV) and the lowest unoccupied molecular orbital (−3.45 ∼ −3.58 eV) energy levels of these 1,5,2,4,6,8-dithiotetrazocine derivatives show that they would be potential acceptor materials. Based on theoretical calculations, thermodynamic study on charge transfer at donor/acceptor interface was carried out. The results of experiments and theoretical calculations show that the electrons could transfer spontaneously from poly(3-hexylthiophene) to these acceptors. The percentages of fluorescence quenching increase with negative Gibbs free energy values increasing in the charge transfer procedures. Therefore, short circuit current values of organic solar cells would increase with the Gibbs free energy values increasing. This paper suggests a useful way for developing efficient organic solar cells. - Highlights: • Syntheses of planar 1,5,2,4,6,8-dithiotetrazocine derivatives for develop effective acceptor. • Electrons at excited state in P3HT could transfer spontaneously to these acceptors. • Thermodynamic study on charge transfer at donor/acceptor interface. • Short circuit currents would be predicted by Gibbs free energy in procedure of charge transfer.

  3. Microwave-assisted convenient syntheses of 2-indolizine derivatives from Morita-Baylis-Hillman adducts: new in silico potential ion channel modulators

    International Nuclear Information System (INIS)

    Cunha, Saraghina M.D.; Oliveira, Ramon G. de; Vasconcellos, Mario L.A.A.

    2013-01-01

    In this work, a microwave-assisted synthesis study by microwave irradiation to produce indolizine-2-carbonitrile and indolizine-2-carboxylate in good to high yields (70 and 81%, respectively) in one step from Morita-Baylis-Hillman adducts (MBHA) is presented. These compounds were subsequently transformed to high yields (94 to 100%, respectively) in three 2-indolizine derivatives. The five synthesized compounds were designed in silico aiming to present potential selective activities as ion channel modulators. These activities were suggested by the score values using Molinspiration Cheminformatics program. (author)

  4. Characterization of the Materials Synthesized by High Pressure-High Temperature Treatment of a Polymer Derived t-BC2N Ceramic

    Directory of Open Access Journals (Sweden)

    Gabriela Mera

    2011-11-01

    Full Text Available Bulk B-C-N materials were synthesized under static high thermobaric conditions (20 GPa and 2,000 °C in a multianvil apparatus from a polymer derived t-BC1.97N ceramic. The bulk samples were characterised using X-ray synchrotron radiation and analytical transmission electron microscopy in combination with electron energy loss spectroscopy. Polycrystalline B-C-N materials with a cubic type structure were formed under the applied reaction conditions, but the formation of a ternary cubic diamond-like c-BC2N compound, could not be unambiguously confirmed.

  5. Characterization of the Materials Synthesized by High Pressure-High Temperature Treatment of a Polymer Derived t-BC2N Ceramic

    OpenAIRE

    Matizamhuka, Wallace R.; Sigalas, Iakovos; Herrmann, Mathias; Dubronvinsky, Leonid; Dubrovinskaia, Natalia; Miyajima, Nobuyoshi; Mera, Gabriela; Riedel, Ralf

    2011-01-01

    Bulk B-C-N materials were synthesized under static high thermobaric conditions (20 GPa and 2,000 ?C) in a multianvil apparatus from a polymer derived t-BC1.97N ceramic. The bulk samples were characterised using X-ray synchrotron radiation and analytical transmission electron microscopy in combination with electron energy loss spectroscopy. Polycrystalline B-C-N materials with a cubic type structure were formed under the applied reaction conditions, but the formation of a ternary cubic diamond...

  6. Characterization of the Materials Synthesized by High Pressure-High Temperature Treatment of a Polymer Derived t-BC₂N Ceramic.

    Science.gov (United States)

    Matizamhuka, Wallace R; Sigalas, Iakovos; Herrmann, Mathias; Dubronvinsky, Leonid; Dubrovinskaia, Natalia; Miyajima, Nobuyoshi; Mera, Gabriela; Riedel, Ralf

    2011-11-29

    Bulk B-C-N materials were synthesized under static high thermobaric conditions (20 GPa and 2,000 °C) in a multianvil apparatus from a polymer derived t-BC 1.97 N ceramic. The bulk samples were characterised using X-ray synchrotron radiation and analytical transmission electron microscopy in combination with electron energy loss spectroscopy. Polycrystalline B-C-N materials with a cubic type structure were formed under the applied reaction conditions, but the formation of a ternary cubic diamond-like c-BC₂N compound, could not be unambiguously confirmed.

  7. Microwave-assisted convenient syntheses of 2-indolizine derivatives from Morita-Baylis-Hillman adducts: new in silico potential ion channel modulators

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Saraghina M.D.; Oliveira, Ramon G. de; Vasconcellos, Mario L.A.A., E-mail: mlaav@quimica.ufpb.br [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Departamento de Quimica

    2013-03-15

    In this work, a microwave-assisted synthesis study by microwave irradiation to produce indolizine-2-carbonitrile and indolizine-2-carboxylate in good to high yields (70 and 81%, respectively) in one step from Morita-Baylis-Hillman adducts (MBHA) is presented. These compounds were subsequently transformed to high yields (94 to 100%, respectively) in three 2-indolizine derivatives. The five synthesized compounds were designed in silico aiming to present potential selective activities as ion channel modulators. These activities were suggested by the score values using Molinspiration Cheminformatics program. (author)

  8. Luminescence and Electronic Spectral Studies of Some Synthesized Lanthanide Complexes Using Benzoic Acid Derivative and o-Phenanthroline.

    Science.gov (United States)

    Wankar, Sneha; Limaye, S N

    2015-07-01

    Lanthanide complexes of p-nitrobenzoic acid(p-NBA) and o-phenanthroline(o-phen) namely [Ln2(Phen)2(p-NBA)3(NO3)2].2H2O where, Ln = Sm(III),Tb(III),Dy(III) and [Eu2(Phen)2(p-NBA)3].4H2O were synthesized and further characterized by Elemental analysis, UV spectroscopy, IR spectroscopy, (1)HNMR spectroscopy. Luminescence measurements were performed on all compounds in ethanolic solution. These complexes have showed narrow emission indicating that the organic ligands are better energy absorber and capable of transferring energy to the Ln (III) ion. Furthermore, we reported electronic spectral studies on [Eu2 (Phen)2 (p-NBA)3].4H2O in order to calculate following parameters, viz: Oscillator strength (f), Judd-Ofelt parameters Ωλ (λ = 2,4,6) and Radiative parameters. [Eu2 (o-Phen)2 (p-NBA)3].4H2O showed the strongest emission at 613 nm corresponds to (5)D0→(7)F2 hypersensitive transition, this emission is very sensitive to the environment. However, the larger value of Ω2 supports the presence of the hypersensitive transition (5)D0→(7)F2 which strictly depends on the nature of ligand. All electronic spectral parameters were calculated systemically.

  9. Spectroscopic and theoretical investigation of conformational changes of proteins by synthesized pyrimidine derivative and its sensitivity towards FRET application

    Science.gov (United States)

    Ghosh, Swadesh; Singharoy, Dipti; Bhattacharya, Subhash Chandra

    2018-04-01

    Interest in synthesizing and characterizing (IR, NMR and HRMS spectroscopic methods) a pyrimidine based Schiff-base ligand, 2-(2-(Anthracen-9-ylmethylene) hydrazinyl)-4,6-dimethyl pyrimidine (ANHP) has been developed for its application to ascertain the conformational change of protein and sensitivity towards fluorescence resonance energy transfer (FRET) process. Location of ANHP in bovine serum albumin (BSA) and human serum albumin (HSA) proteins environment has been determined using different spectroscopic techniques. Weakly fluorescent ANHP have shown greater protein induced fluorescence enhancement (PIFE) in case of HSA than BSA, though in both cases energy transfer efficiency are almost same but difference in binding constant values encourages us to find the location of ANHP within the complex protein environment. From the FRET parameter and α-helicity change, it has been found that ANHP bound with Trp-214 of HSA and surface Trp-134 of BSA. Conformational changes of proteins have been observed more for HSA than BSA in presence of ANHP, which has confirmed the location of ANHP in both the protein environments. Coupled with experimental studies, molecular docking analysis has also been done to explain the locations and distance dependent FRET process of ANHP in both proteins.

  10. Syntheses of nicotinamide riboside and derivatives: effective agents for increasing nicotinamide adenine dinucleotide concentrations in mammalian cells.

    Science.gov (United States)

    Yang, Tianle; Chan, Noel Yan-Ki; Sauve, Anthony A

    2007-12-27

    A new two-step methodology achieves stereoselective synthesis of beta-nicotinamide riboside and a series of related amide, ester, and acid nucleosides. Compounds were prepared through a triacetylated-nicotinate ester nucleoside, via coupling of either ethylnicotinate or phenylnicotinate with 1,2,3,5-tetra-O-acetyl-beta-D-ribofuranose. Nicotinamide riboside, nicotinic acid riboside, O-ethylnicotinate riboside, O-methylnicotinate riboside, and several N-alkyl derivatives increased NAD+ concentrations from 1.2-2.7-fold in several mammalian cell lines. These findings establish bioavailability and potent effects of these nucleosides in stimulating the increase of NAD+ concentrations in mammalian cells.

  11. Efficient hydrogenation of biomass-derived furfural and levulinic acid on the facilely synthesized noble-metal-free Cu–Cr catalyst

    International Nuclear Information System (INIS)

    Yan, Kai; Chen, Aicheng

    2013-01-01

    Biomass-derived platform intermediate furfural and levulinic acid were efficiently hydrogenated to the value-added furfuryl alcohol and promising biofuel γ-valerolactone, respectively, using a noble-metal-free Cu–Cr catalyst, which was facilely and successfully synthesized by a modified co-precipitation method using the cheap metal nitrates. In the first hydrogenation of furfural, 95% yield of furfuryl alcohol was highly selectively produced at 99% conversion of furfural under the mild conditions. For the hydrogenation of levulinic acid, 90% yield of γ-valerolactone was highly selectively produced at 97.8% conversion. Besides, the physical properties of the resulting Cu–Cr catalysts were studied by XRD (X-ray diffraction), EDX (Energy-dispersive X-ray), TEM (Transmission electron microscopy) and XPS (X-ray photoelectron spectroscopy) to reveal their influence on the catalytic performance. Subsequently, different reaction parameters were studied and it was found that Cu 2+ /Cr 3+ ratios (0.5, 1 and 2), reaction temperature (120–220 °C) and hydrogen pressure (35–70 bar) presented important influence on the catalytic activities. In the end, the stability of the Cu–Cr catalysts was also studied. - Highlights: • A noble-metal-free Cu–Cr catalyst was successfully synthesized using metal nitrates. • Cu–Cr catalysts were highly selective hydrogenation of biomass-derived furfural to FA. • Cu–Cr catalysts were efficient for hydrogenation of biomass-derived LA to biofuel GVL. • The physical properties of the resulting Cu–Cr catalysts were systematically studied. • Reaction parameters and stability in the hydrogenation of furfural were studied in details

  12. Study of hafnium (IV) oxide nanoparticles synthesized by polymerized complex and polymer precursor derived sol-gel methods

    KAUST Repository

    Ramos-González, R.

    2010-03-01

    This work reports the preparation and characterization of hafnium (IV) oxide (HfO2) nanoparticles grown by derived sol-gel routes that involves the formation of an organic polymeric network. A comparison between polymerized complex (PC) and polymer precursor (PP) methods is presented. For the PC method, citric acid (CA) and ethylene glycol (EG) are used as the chelating and polymerizable reagents, respectively. In the case of PP method, poly(acrylic acid) (PAA) is used as the chelating reagent. In both cases, different precursor gels were prepared and the hafnium (IV) chloride (HfCl4) molar ratio was varied from 0.1 to 1.0 for the PC method and from 0.05 to 0.5 for the PP method. In order to obtain the nanoparticles, the precursors were heat treated at 500 and 800 °C. The thermal characterization of the precursor gels was carried out by thermogravimetric analysis (TGA) and the structural and morphological characterization by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The XRD patterns of the samples obtained by both methods shows the formation of HfO2 at 500 °C with monoclinic crystalline phase. The PC method exhibited also the cubic phase. Finally, the HfO2 nanoparticles size (4 to 11 nm) was determined by TEM and XRD patterns. © (2010) Trans Tech Publications.

  13. Structural characterization of glucosylated lactose derivatives synthesized by the Lactobacillus reuteri GtfA and Gtf180 glucansucrase enzymes.

    Science.gov (United States)

    Pham, Hien T T; Dijkhuizen, Lubbert; van Leeuwen, Sander S

    2017-09-08

    Glucansucrase enzymes from lactic acid bacteria are receiving strong interest because of their wide range of gluco-oligosaccharide and polysaccharide products from sucrose, some of which have prebiotic potential. Glucansucrases GtfA and Gtf180 from Lactobacillus reuteri strains are known to convert sucrose into α-glucans with different types of linkages, but also to use other molecules as acceptor substrates. Here we report that incubation of (N-terminally truncated versions of) these enzymes with lactose plus sucrose resulted in synthesis of at least 5 glucosylated lactose products of a degree of polymerization (DP) of 3-4. Only glucansucrase Gtf180-ΔN also produced larger lactose-based oligosaccharides (up to DP9). Structural characterization of the glucosylated lactose products DP3-4 revealed glycosidic bonds other than (α1→4)/(α1→6) typical for GtfA-ΔN and (α1→3)/(α1→6) typical for Gtf180-ΔN: Both GtfA-ΔN and Gtf180-ΔN now introduced a glucosyl residue (α1→3)- or (α1→4)-linked to the non-reducing galactose unit of lactose. Both enzymes also were able to introduce a glucosyl residue (α1→2)-linked to the reducing glucose unit of lactose. These lactose derived oligosaccharides potentially are interesting prebiotic compounds. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Cytotoxicity assessment of adipose-derived mesenchymal stem cells on synthesized biodegradable Mg-Zn-Ca alloys.

    Science.gov (United States)

    Fazel Anvari-Yazdi, Abbas; Tahermanesh, Kobra; Hadavi, Seyed Mohammad Mehdi; Talaei-Khozani, Tahereh; Razmkhah, Mahboobeh; Abed, Seyedeh Mehr; Mohtasebi, Maryam Sadat

    2016-12-01

    Magnesium (Mg)-based alloys have been extensively considered as biodegradable implant materials for orthopedic surgery. Mg and its alloys are metallic biomaterials that can degrade in the body and promote new bone formation. In this study, the corrosion behavior and cytotoxicity of Mg-Zn-Ca alloys are evaluated with adipose-derived mesenchymal stem cells (ASCs). Mg-2Zn and Mg-2Zn-xCa (x=1, 2 and 3wt.%) alloys were designated. Mg alloys were analyzed with scanning electron microscopy and potentiodynamic polarization. To understand the in-vitro biocompatibility and cytotoxicity of Mg-2Zn and Mg-2Zn-xCa alloys, ASCs were cultured for 24 and 72h in contact with 10%, 50% and 100% extraction of all alloys prepared in DMEM. Cell cytotoxicity and viability of ASCs were examined by MTT assay. Alloying elements including Zn and Ca improved the corrosion resistance of alloys were compared with pure Mg. The cytotoxicity results showed that all alloys had no significant adverse effects on cell viability in 24h. After 72h, cell viability and proliferation increased in the cells exposed to pure Mg and Mg-2Zn-1Ca extracts. The release of Mg, Zn and Ca ions in culture media had no toxic impacts on ASCs viability and proliferation. Mg-2Zn-1Ca alloy can be suggested as a good candidate to be used in biomedical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Syntheses and structure characterization of ten acid-base hybrid crystals based on imidazole derivatives and mineral acids

    Science.gov (United States)

    Hu, Kaikai; Deng, Bowen; Jin, Shouwen; Ding, Aihua; Jin, Shide; Zhu, Jin; Zhang, Huan; Wang, Daqi

    2018-04-01

    Cocrystallization of the imidazole derivatives with a series of mineral acids gave a total of ten hybrid salts with the compositions: [(H2bzm)(Cl)2·3H2O] (1), [(H2bzm)(ClO4)2] (2), [(H2bze)(Cl)2·2H2O] (3), [(H2bze)(Br)2·2H2O] (4), [(H2bzp)(Cl)2·4H2O] (5), [(H2bzp)(Br)2·4H2O] (6), (2-(imidazol-1-yl)-1-phenylethanone): (phosphoric acid) [(Himpeta)+(H2PO4)-] (7), [(H2impd)(Br)2] (8), [(H2impd)(ClO4)2] (9), and [(Hbzml)(Cl)] (10). The ten salts have been characterised by X-ray diffraction analysis, IR, and elemental analysis, and the melting points of all the salts were also reported. And their structural and supramolecular aspects are fully analyzed. The result reveals that among the ten investigated crystals the ring N atoms of the imidazole are protonated when the acids are deprotonated, and the crystal packing is interpreted in terms of the strong charge-assisted classical H-bonds between the NH+ and deprotonated acidic groups. Further analysis of the crystal packing of the salts indicated that a different set of additional CHsbnd O, CH2sbnd O, CHsbnd Cl, CH2sbnd Cl, CHsbnd N, CHsbnd Br, CH2sbnd Br, Osbnd O, O-π, Br-π, CH-π, and π-π associations contribute to the stabilization and expansion of the total high-dimensional frameworks. For the coexistence of the various weak nonbonding interactions these structures adopted homo or hetero supramolecular synthons or both. Some classical supramolecular synthons, such as R21(7), R22(7), R22(8), and R42(8), usually observed in the organic solids, were again shown to be involved in constructing some of these H-bonding networks.

  16. The Chemically Synthesized Ageladine A-Derivative LysoGlow84 Stains Lysosomes in Viable Mammalian Brain Cells and Specific Structures in the Marine Flatworm Macrostomum lignano

    Directory of Open Access Journals (Sweden)

    Thorsten Mordhorst

    2015-02-01

    Full Text Available Based on the chemical structure and the known chemical synthesis of the marine sponge alkaloid ageladine A, we synthesized the ageladine A-derivative 4-(naphthalene-2-yl-1H-imidazo[4,5-c]pyridine trifluoroacetate (LysoGlow84. The two-step synthesis started with the Pictet-Spengler reaction of histamine and naphthalene-2-carbaldehyde to a tetrahydropyridine intermediate, which was dehydrogenated with activated manganese (IV oxide to LysoGlow84. Structure and purity of the synthesized LysoGlow84 were confirmed by NMR spectroscopy and mass spectrometry. The fluorescence intensity emitted by LysoGlow84 depended strongly on the pH of the solvent with highest fluorescence intensity recorded at pH 4. The fluorescence maximum (at 315 nm excitation was observed at 440 nm. Biocompatibility of LysoGlow84 was investigated using cultured rat brain astrocytes and the marine flatworm Macrostomum lignano. Exposure of the astrocytes for up to 6 h to micromolar concentrations of LysoGlow84 did not compromise cell viability, as demonstrated by several viability assays, but revealed a promising property of this compound for staining of cellular vesicles. Conventional fluorescence microscopy as well as confocal scanning microscopy of LysoGlow84-treated astrocytes revealed co-localization of LysoGlow84 fluorescence with that of LysoTracker® Red DND-99. LysoGlow84 stained unclear structures in Macrostomum lignano, which were identified as lysosomes by co-staining with LysoTracker. Strong fluorescence staining by LysoGlow84 was further observed around the worms’ anterior gut and the female genital pore which were not counterstained by LysoTracker Red. Thus, LysoGlow84 is a new promising dye that stains lysosomes and other acidic compartments in cultured cells and in worms.

  17. The chemically synthesized ageladine A-derivative LysoGlow84 stains lysosomes in viable mammalian brain cells and specific structures in the marine flatworm Macrostomum lignano.

    Science.gov (United States)

    Mordhorst, Thorsten; Awal, Sushil; Jordan, Sebastian; Petters, Charlotte; Sartoris, Linda; Dringen, Ralf; Bickmeyer, Ulf

    2015-02-11

    Based on the chemical structure and the known chemical synthesis of the marine sponge alkaloid ageladine A, we synthesized the ageladine A-derivative 4-(naphthalene-2-yl)-1H-imidazo[4,5-c]pyridine trifluoroacetate (LysoGlow84). The two-step synthesis started with the Pictet-Spengler reaction of histamine and naphthalene-2-carbaldehyde to a tetrahydropyridine intermediate, which was dehydrogenated with activated manganese (IV) oxide to LysoGlow84. Structure and purity of the synthesized LysoGlow84 were confirmed by NMR spectroscopy and mass spectrometry. The fluorescence intensity emitted by LysoGlow84 depended strongly on the pH of the solvent with highest fluorescence intensity recorded at pH 4. The fluorescence maximum (at 315 nm excitation) was observed at 440 nm. Biocompatibility of LysoGlow84 was investigated using cultured rat brain astrocytes and the marine flatworm Macrostomum lignano. Exposure of the astrocytes for up to 6 h to micromolar concentrations of LysoGlow84 did not compromise cell viability, as demonstrated by several viability assays, but revealed a promising property of this compound for staining of cellular vesicles. Conventional fluorescence microscopy as well as confocal scanning microscopy of LysoGlow84-treated astrocytes revealed co-localization of LysoGlow84 fluorescence with that of LysoTracker® Red DND-99. LysoGlow84 stained unclear structures in Macrostomum lignano, which were identified as lysosomes by co-staining with LysoTracker. Strong fluorescence staining by LysoGlow84 was further observed around the worms' anterior gut and the female genital pore which were not counterstained by LysoTracker Red. Thus, LysoGlow84 is a new promising dye that stains lysosomes and other acidic compartments in cultured cells and in worms.

  18. Syntheses of Novel 4-Substituted N-(5-amino-1H-1,2,4-triazol-3-ylpyridine-3-sulfonamide Derivatives with Potential Antifungal Activity

    Directory of Open Access Journals (Sweden)

    Krzysztof Szafrański

    2017-11-01

    Full Text Available Candidiasis represent a serious threat for patients with altered immune responses. Therefore, we have undertaken the synthesis of compounds comprising a pyridine-3-sulfonamide scaffold and known antifungally active 1,2,4-triazole substituents. Thus a series of novel 4-substituted N-(5-amino-1H-1,2,4-triazol-3-ylpyridine-3-sulfonamides have been synthesized by multistep reactions starting from 4-chloropyridine-3-sulfonamide via N′-cyano-N-[(4-substitutedpyridin-3-ylsulfonyl]carbamimidothioates which were further converted with hydrazine hydrate to the corresponding 1,2,4-triazole derivatives 26–36. The final compounds were evaluated for antifungal activity against strains of the genera Candida, Geotrichum, Rhodotorula, and Saccharomycess isolated from patients with mycosis. Many of them show greater efficacy than fluconazole, mostly towards Candida albicans and Rhodotorula mucilaginosa species, with MIC values ≤ 25 µg/mL. A docking study of the most active compounds 26, 34 and 35 was performed showing the potential mode of binding to Candida albicans lanosterol 14α-demethylase. Also in vitro cytotoxicity of selected compounds have been evaluated on the NCI-60 cell line panel.

  19. Synthesis of a polymer-bound galactosylamine and its application as an immobilized chiral auxiliary in stereoselective syntheses of piperidine and amino acid derivatives.

    Science.gov (United States)

    Zech, Gernot; Kunz, Horst

    2004-09-06

    A 2,3,4-tri-O-pivaloylated beta-D-galactopyranosyl azide bearing a hydroxy-functionalized spacer unit at the C-6 position of the galactose was synthesized and immobilized on the solid phase by using a polymer-bound chlorosilane. The azide was reduced to the corresponding galactopyranosylamine, which served as a versatile chiral auxiliary in highly diastereoselective Ugi four-component condensation reactions at ambient temperature. Fluoride-induced cleavage from the polymeric support furnished N-glycosylated N-acylated alpha-amino acid amides. The reaction of the immobilized galactosylamine with aldehydes gave rise to the corresponding aldimines, which underwent a domino Mannich-Michael condensation reaction with Danishefsky's diene at ambient temperature to yield 2-substituted 5,6-didehydropiperidin-4-ones on the solid phase. Subsequent cleavage with tetra-n-butylammonium fluoride delivered the N-glycosylated products in high yields, purities, and diastereoselectivities. A chemoselective 1,4-hydride addition to the polymer-bound dehydropiperidinones was achieved in the presence of the bulky oxygenophilic Lewis acid methylaluminum [bis(2,6-di-tert-butyl-4-methylphenoxide)]. The conjugate addition of cyano-modified Gilman reagents to the immobilized dehydropiperidinones furnished 2,6-cis-substituted piperidine derivatives as the major diastereomers that were isolated after cleavage from the support.

  20. Copper and manganese complexes based on 1,4-naphthalene dicarboxylic acid ligand and its derivative: Syntheses, crystal structures, and magnetic properties

    Science.gov (United States)

    Xing, Yubo; Liu, Yuqi; Xue, Xiaofei; Wang, Xinying; Li, Wei

    2018-02-01

    Three new metal-organic coordination polymers, {[Mn2(1,4-NDC)2 (C2H5OH) (DMF) (H2O)]·CH3OH}n(1), {[Mn(III)(1,4-NDC)(C2H5O)][Mn(II)(1,4-NDC)(DMF)(H2O)]}n(2) and {[Cu2(C13H9O4)4(H2O)2]}n(3) based on1,4-H2NDC and its derivative were hydrothermally synthesized (1,4-H2NDC = 1,4-naphthalene-dicarboxylic acid, C13H10O4 = 4-methyl formate-1-naphthalenecarboxylic acid), and characterized by techniques of single crystal X-ray diffraction, infrared spectra (IR), elemental analysis, powder X-ray diffraction(PXRD) and variable-temperature magnetic susceptibility measurements. X-ray crystal structure analyses reveal that complexes 1 and 2 show a same 3,5-connected fsc 3D topology network with the Schlȁfli symbol of {4·6·8}{4·66·83}. But, the valence of some Mn atom in complex 2 take place transition from the +II oxidation state to the +III oxidation state, which may be the effect of the different solvent ratio. In complex 3, the Cu⋯Cu distance of 2.620(13) Å is significantly shorter than the sum of the van der Waals radii of Cu (1.40 Å), resulting in a strong ferromagnetic interaction between the Cu(II) centers. Furthermore, the temperature-dependent magnetic susceptibility measurements exhibit overall antiferromagnetic interactions between manganese ions for complexes 1 and 2, and a strong ferromagnetic interaction between the Cu(II) centers for complex 3.

  1. Synthesis of sulfates and sulfate derivates of selected metals under harsh conditions; Synthese von Sulfaten und Sulfatderivaten ausgewaehlter Metalle unter drastischen Bedingungen

    Energy Technology Data Exchange (ETDEWEB)

    Neuschulz, Kai

    2015-03-24

    In the course of this work sulfates und sulfate derivates of selected metals were synthesized under harsh conditions. The obtained compounds, in which the metal ions often reveal unusual oxidation states, have been characterized. Two mixed valent vanadium(IV/V) oxide sulfates (VO){sub 4}(SO{sub 4}){sub 5}, and (VO){sub 3}(SO{sub 4}){sub 4} and a vanadium(V) oxide sulfate (VO){sub 2}(SO{sub 4}){sub 3} as well as a complex anionic vanadium(V) oxide sulfate (NO)[VO(SO{sub 4}){sub 2}] have been obtained starting from vanadium or vanadium(V) oxide and oleum. All vanadium oxide sulfates reveal a similar thermal behavior. The decomposition residues are either pure vanadium(V) oxide or vanadium(IV) oxide or a mixture of both residues in different ratios. It was possible to synthesize binary tantalum(V) sulfate Ta{sub 2}(SO{sub 4}){sub 5} for the first time by reaction of pure sulfur(VI) oxide and tantalum(V) oxide at 150 C and to characterize. The complete absence of any oxide ligands at the metal center is of special interest in this compound. The reaction of tin(II) sulfate with oleum lead to the formation of tin(IV) sulfate Sn(SO{sub 4}){sub 2}. Using IR spectroscopy, the oxidation state +IV was confirmed for tin, due to the absence of OH-band in the IR-spectra, which would have meant the oxidation state +II. Using methanesulfonic acid as solvent and reactant on different synthetic routes the anhydrous methanesulfonates Mn(CH{sub 3}SO{sub 3}){sub 2}, and Fe(CH{sub 3}SO{sub 3}){sub 2}, Ga(CH{sub 3}SO{sub 3}){sub 3}, In(CH{sub 3}SO{sub 3}){sub 3}, and Tl(CH{sub 3}SO{sub 3}){sub 3}, as well as VO(CH{sub 3}SO{sub 3}){sub 2} and SnCl{sub 2}(CH{sub 3}SO{sub 3}){sub 2} were obtained. For the element thallium it was possible to obtain two mixed anionic compounds with the composition TlX{sub 2}(CH{sub 3}SO{sub 3}) (X = Cl or Br). All methanesulfonates show a similar thermal decomposition behavior forming the metal oxide as decomposition product. The thallium compounds represent

  2. Bolus injection of newly synthesized vitamin E derivative ETS-GS for the treatment of acute severe ulcerative colitis in a mouse model. New vitamin E derivative for acute severe UC.

    Science.gov (United States)

    Hiratsuka, Takahiro; Inomata, Masafumi; Hagiwara, Satoshi; Kono, Yohei; Shiraishi, Norio; Noguchi, Takayuki; Kitano, Seigo

    2013-03-01

    Vitamin E with its antioxidant action has therapeutic effects on ulcerative colitis (UC), but use of vitamin E is limited because of its insolubility in water. We developed ETS-GS (γ-L-glutamyl-S-[2-[[[3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltri-decyl)-2 H-1-benzopyran-6-yl]oxy]carbonyl]-3-oxo-3-[(2-sulfoethyl)amino]propyl]-L-cysteinylglycine sodium salt), a newly synthesized soluble vitamin E derivative with strong antioxidant action. We evaluated the therapeutic effects of bolus injection of ETS-GS on acute severe UC in a mouse model. An animal model of acute severe UC was induced by feeding mice 5 % dextran sulfate sodium (DSS) for 5 days, followed by 1 % DSS on days 5-8, the experimental period. ETS-GS or saline was administered by subcutaneous bolus injection during the experimental period. We examined disease activity index (DAI) score, histological score, colon length, colon weight, and serum cytokines in the mice. The following results at day 8 in the DSS + ETS-GS group were significantly lower than those in the DSS + Saline group: DAI score, 2.6 ± 0.6 vs. 3.1 ± 0.5; histological score, 2.1 ± 1.0 vs. 3.1 ± 0.8; serum interleukin (IL)-6, 15 ± 9.4 vs. 39 ± 23 pg/ml; and keratinocyte-derived chemokine (KC), 122 ± 61 vs. 228 ± 66 pg/ml (P UC. Its effects are associated with suppression of serum IL-6 and serum KC and promotion of serum IL-10.

  3. Optical and morphological properties of ZnO- and TiO2-derived nanostructures synthesized via a microwave-assisted hydrothermal method

    CSIR Research Space (South Africa)

    Moloto, N

    2012-01-01

    Full Text Available A microwave-assisted hydrothermal method was used to synthesize ZnO and TiO2 nanostructures. The experimental results show that the method resulted in crystalline monodispersed ZnO nanorods that have pointed tips with hexagonal crystal phase. TiO2...

  4. Synthesis, characterization and nano-structuration of poly-thiophene derivatives for organic photovoltaic solar cells; Synthese, caracterisation et nanostructuration de derives du polythiophene pour des applications en cellules photovoltaiques organiques

    Energy Technology Data Exchange (ETDEWEB)

    Berson, S

    2007-10-15

    This work is devoted to the synthesis of poly-thiophene derivatives with low bandgap and preserving high oxidation potential. Disubstituted thiophenes and 'Donor-Acceptor' bi-thiophenes were synthesized and then polymerized. The side chains of these polymers, donor or acceptor, were modified in order to tune the properties of material as well from the optical point of view as electrochemical. These polymers were also tested in blend with PCBM in bulk-heterojunction photovoltaic cells. Voc delivered by the devices showed a linear dependence according to the potential of oxidation of the polymers. Copolymers containing cyano-thiophene and alkyl- or alkoxy-thiophene showed values of 0.8 V. However, in spite of power conversion efficiency of 1 %, these performances remain lower than the one obtained with the P3HT. Optimizations in terms of morphology are certainly necessary. Indeed, the morphology of the active layer plays a key role in obtaining high power conversion efficiency. An original technique of nano-structuration of the polymer on a nano-metric scale was developed during this work, leading to the development of fibrillar P3HT. These nano-structures, presenting an important degree of order, are formed spontaneously in solution. Their rate compared to amorphous material is perfectly controllable and adjustable in solution and in solid state. Measurements of mobilities show a strong improvement of the transport of load within these fibrillar layers compared to a traditional film of P3HT obtained without annealing. Power conversion efficiencies of 3.6% on glass and 3.3 % on plastic were reached without annealing. (author)

  5. Syntheses, crystal structures, spectral study and DFT calculation of three new copper(II) complexes derived from pyridoxal hydrochloride, N,N-dimethylethylenediamine and N,N-diethylethylenediamine

    Science.gov (United States)

    Mandal, Senjuti; Naskar, Barnali; Modak, Ritwik; Sikdar, Yeasin; Chatterjee, Sudipta; Biswas, Sujan; Mondal, Tapan Kumar; Modak, Debadrita; Goswami, Sanchita

    2015-05-01

    Two pyridoxal containing Schiff bases obtained by condensation of pyridoxal hydrochloride with N,N-dimethylethylenediamine (HL1) and N,N-diethylethylenediamine (HL2) are used for the syntheses of three new copper (II) complexes [Cu(HL1)(H2O)Cl]Cl (1), [Cu(L1)Cl] (2) and [Cu(L2)Cl] (3). The single crystal X-ray structures of all the three copper(II) complexes are determined. Redox potentials for the mononuclear complexes are measured by cyclic voltammetry experiments. The DFT and TDDFT results have been used to interpret the experimental properties.

  6. Inhibition Effects of a Synthesized Novel 4-Aminoantipyrine Derivative on the Corrosion of Mild Steel in Hydrochloric Acid Solution together with Quantum Chemical Studies

    Directory of Open Access Journals (Sweden)

    Abu Bakar Mohamad

    2013-06-01

    Full Text Available 1,5-Dimethyl-4-((2-methylbenzylideneamino-2-phenyl-1H-pyrazol-3(2H-one (DMPO was synthesized to be evaluated as a corrosion inhibitor. The corrosion inhibitory effects of DMPO on mild steel in 1.0 M HCl were investigated using electrochemical impedance spectroscopy (EIS, potentiodynamic polarization, open circuit potential (OCP and electrochemical frequency modulation (EFM. The results showed that DMPO inhibited mild steel corrosion in acid solution and indicated that the inhibition efficiency increased with increasing inhibitor concentration. Changes in the impedance parameters suggested an adsorption of DMPO onto the mild steel surface, leading to the formation of protective films. The novel synthesized corrosion inhibitor was characterized using UV-Vis, FT-IR and NMR spectral analyses. Electronic properties such as highest occupied molecular orbital energy, lowest unoccupied molecular orbital energy (EHOMO and ELUMO, respectively and dipole moment (μ were calculated and discussed. The results showed that the corrosion inhibition efficiency increased with an increase in the EHOMO values but with a decrease in the ELUMO value.

  7. Syntheses of dibenzo[d,d']benzo[2,1-b:3,4-b']difuran derivatives and their application to organic field-effect transistors

    Directory of Open Access Journals (Sweden)

    Minh Anh Truong

    2016-04-01

    Full Text Available Ladder-type π-conjugated compounds containing a benzo[2,1-b:3,4-b']difuran skeleton, such as dibenzo[d,d']benzo[2,1-b:3,4-b']difuran (syn-DBBDF and dinaphtho[2,3-d:2',3'-d']benzo[2,1-b:3,4-b']difuran (syn-DNBDF were synthesized. Their photophysical and electrochemical properties were revealed by UV–vis absorption and photoluminescence spectroscopy and cyclic voltammetry. Organic field-effect transistors (OFETs were fabricated with these compounds as organic semiconductors, and their semiconducting properties were evaluated. OFETs with syn-DBBDF and syn-DNBDF showed typical p-type characteristics with hole mobilities of −3 cm2·V−1·s−1 and −1 cm2·V−1·s−1, respectively.

  8. Synthesis of some new 4-oxo-thiazolidines, tetrazole and triazole derived from 2-SH-benzothiazole and antimicrobial screening of some synthesized

    Directory of Open Access Journals (Sweden)

    Suaad M.H. Al-Majidi

    2014-12-01

    Triazole moieties reported condensation (MBT with ethylbromo acetate and potassium hydroxide by the fusion method and resulted in ester-2-mercaptobenzothiazole (7, which was treated with hydrazine hydrate to give a hydrazine derivative (8, then converting these compounds (8 to phenyl semicarbazide (9 and phenyl thiosemicarbazide (10 derivatives. Cyclization compounds (9,10 in alkaline media (4 N·NaOH gave triazoles compounds (11,12. Furthermore the compound (8 was converted to the dithiocarbazate salt (13 which was then cyclized with hydrazine hydrate to give substituted triazole (14. The prepared compounds were identified by spectral methods (FTIR, 1H NMR, 13C NMR and some of its physical properties were measured and furthermore the effects of the preparing compounds on some strains of bacteria were studied.

  9. Syntheses of dibenzo[d,d']benzo[2,1-b:3,4-b']difuran derivatives and their application to organic field-effect transistors

    Science.gov (United States)

    Truong, Minh Anh

    2016-01-01

    Summary Ladder-type π-conjugated compounds containing a benzo[2,1-b:3,4-b']difuran skeleton, such as dibenzo[d,d']benzo[2,1-b:3,4-b']difuran (syn-DBBDF) and dinaphtho[2,3-d:2',3'-d']benzo[2,1-b:3,4-b']difuran (syn-DNBDF) were synthesized. Their photophysical and electrochemical properties were revealed by UV–vis absorption and photoluminescence spectroscopy and cyclic voltammetry. Organic field-effect transistors (OFETs) were fabricated with these compounds as organic semiconductors, and their semiconducting properties were evaluated. OFETs with syn-DBBDF and syn-DNBDF showed typical p-type characteristics with hole mobilities of <1.5 × 10−3 cm2·V−1·s−1 and <1.0 × 10−1 cm2·V−1·s−1, respectively. PMID:27340471

  10. Antibacterial polymeric nanocomposites synthesized by in-situ photoreduction of silver ions without additives inside biocompatible hydrogel matrices based on N-isopropylacrylamide and derivatives

    Directory of Open Access Journals (Sweden)

    M. Monerris

    2017-12-01

    Full Text Available Synthesis of antibacterial nanocomposite obtained by in-situ photoreduction of Ag+ ions impregnated inside a biocompatible hydrogel matrix is described. Hydrogel matrixes based on N-isopropylacrylamide (PNIPAM and copolymers are synthesized by free radical polymerization in aqueous medium. The hydrogels are loaded with Ag+ ions and then silver nanoparticles (Ag-NPs are obtained in-situ by application of UV light without using additives. Ag-NPs formation inside hydrogels is confirmed by UV–visible spectroscopy, scanning electronic microscopy (SEM and transmission electronic microscopy (TEM. An extensive characterization of nanocomposites is performed by determining the partition coefficient of Ag+ ions before photoreduction, the Ag-NPs mass loaded per gram of hydrogel as a function of irradiation time, swelling capacity and volume phase transition temperature. Fourier Transform Infrared (FTIR spectra indicate the loss of some functional groups of the polymer backbone during reduction of Ag+ ions whereas 13C NMR spectra do not show any change in the main carbon chain. Nanocomposites show antibacterial activity against Pseudomonas aeruginosas by release of Ag+ ions while Ag-NPs remain inside matrix. Reducing/stabilizing character of hydrogel and antibacterial activity of nanocomposite depend on the chemical composition of the matrix.

  11. Ruthenium nitrosyls derived from tetradentate ligands containing carboxamido-N and phenolato-o donors: syntheses, structures, photolability, and time dependent density functional theory studies.

    Science.gov (United States)

    Fry, Nicole L; Rose, Michael J; Rogow, David L; Nyitray, Crystal; Kaur, Manpreet; Mascharak, Pradip K

    2010-02-15

    In order to examine the role(s) of designed ligands on the NO photolability of {Ru-NO}(6) nitrosyls, a set of three nitrosyls with ligands containing two carboxamide groups along with a varying number of phenolates have been synthesized. The nitrosyls namely, (NEt(4))(2)[(hybeb)Ru(NO)(OEt)] (1), (PPh(4))[(hypyb)Ru(NO)(OEt)] (2), and [(bpb)Ru(NO)(OEt)] (3) have been characterized by X-ray crystallography. Complexes 1-3 are diamagnetic, exhibit nu(NO) in the range 1780-1840 cm(-1) and rapidly release NO in solution upon exposure to low power UV light (7 mW/cm(2)). Density Functional Theory (DFT) and Time Dependent DFT (TDDFT) calculations on 1-3 indicate considerable contribution of ligand orbitals in the MOs involved in transitions leading to NO photolability. The results of the theoretical studies match well with the experimental absorption spectra as well as the parameters for NO photorelease and provide insight into the transition(s) associated with loss of NO.

  12. Effects of Quinizarin and Five Synthesized Derivatives on Fifth Larval Instar Midgut Ecdysone 20-Monooxygenase Activity of the Tobacco Hornworm Manduca sexta

    Directory of Open Access Journals (Sweden)

    Christopher A. Drummond

    2014-01-01

    Full Text Available The plant allelochemical, quinizarin (1,4-dihydroxy-9,10-anthraquinone, and five anthraquinones that were synthesized from quinizarin, namely, 1,4-anthraquinone; 2-hydroxy-1,4-anthraquinone; 2-methoxy-1,4-anthraquinone; 9-hydroxy-1,4-anthraquinone; and 9-methoxy-1,4-anthraquinone, were assessed as to their effects on the essential, P450-dependent ecdysone 20-monooxygenase system of the insect model Manduca sexta (tobacco hornworm. This steroid hydroxylase converts the arthropod molting hormone, ecdysone, to the physiologically required 20-hydroxyecdysone form. M. sexta fifth larval instar midgut homogenates were incubated with increasing concentrations (10−8 to 10−3 M of each of the six anthraquinones followed by ecdysone 20-monooxygenase assessments using a radioenzymological assay. Four of the five anthraquinones exhibited I50’s of about 4×10-6 to 6×10-2 M. The most effective inhibitors were 2-methoxy-1,4-anthraquinone and 1,4-anthraquinone followed by 9-hydroxy-1,4 anthraquinone and 9-methoxy-1,4-anthraquinone. At lower concentrations the latter anthraquinone stimulated E20M activity. Quinizarin was less inhibitory and 2-hydroxy-1,4-anthraquinone was essentially without effect. Significantly, these studies make evident for the first time that anthraquinones can affect insect E20M activity, and thus insect endocrine regulation and development, and that a relationship between anthraquinone structure and effectiveness is apparent. These studies represent the first demonstrations of anthraquinones affecting any steroid hydroxylase system.

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

    Science.gov (United States)

    Oter, Ozlem; Ertekin, Kadriye; Kirilmis, Cumhur; Koca, Murat

    2007-02-19

    In this work photoluminescent properties of highly Cu(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(f)=6.1 x 10(-2) and molar extinction coefficient, epsilon=29,000+/-65 cm(-1)M(-1) in immobilized PVC matrix, compared to 2.6 x 10(-3) and 24,573+/-115 in ethanol solution. The offered sensor exhibited remarkable fluorescence intensity quenching upon exposure to Cu(2+) ions at pH 4.0 in the concentration range of 1.0 x 10(-9) to 3.0 x 10(-4)M [Cu(2+)] while the effects of the responding ions (Ca(2+), Hg(+), Pb(2+), Al(3+), Cr(3+), Mn(2+), Mg(2+), Sn(2+), Cd(2+), Co(2+) and Ni(2+)) were less pronounced.

  14. Electrochemiluminescence and chemiluminescence of a carboxylic acid derivative of ruthenium(II) tris-(2,2'-bipyridine) chelate synthesized for labeling purposes

    International Nuclear Information System (INIS)

    Jiang Qinghong; Sun Shiguo; Hakansson, Markus; Langel, Kaarina; Ylinen, Tiina; Suomi, Johanna; Kulmala, Sakari

    2006-01-01

    Synthesis, purification and characterization of [4-ethoxycarbonyl-4'-carboxy-2,2'-bipyridine]bis(2,2'-bipyridine) ruthenium(II) hexafluorophosphate is described. This complex is shown to be electrochemiluminescent in aqueous solution during cathodic pulse polarization of thin insulating film-coated electrodes. Electrochemiluminescence (ECL) lifetime of the complex was observed to be ca. 40 μs at oxide-coated n-silicon electrodes; thus time-resolved detection is also possible. The ECL emission maximum of this carboxylate derivative is somewhat red-shifted when compared with an unmodified Ru(bpy) 3 2+ . Because the present complex can be easily covalently coupled with antibodies and oligonucleotides it is usable as an electrochemiluminescent label in various bioaffinity assays. The present chelates also produce strong chemiluminescence during dissolution of metallic magnesium in aqueous solution

  15. Study of the surface modification with oleic acid of nanosized HfO{sub 2} synthesized by the polymerized complex derived sol-gel method

    Energy Technology Data Exchange (ETDEWEB)

    Ramos-Gonzalez, R., E-mail: rramos.phd@gmail.com [Centro de Investigacion en Quimica Aplicada, Blvd. Enrique Reyna Hermosillo No. 140, Saltillo, Coahuila 25250 (Mexico); Garcia-Cerda, L.A. [Centro de Investigacion en Quimica Aplicada, Blvd. Enrique Reyna Hermosillo No. 140, Saltillo, Coahuila 25250 (Mexico); Quevedo-Lopez, M.A. [University of Texas at Dallas, 800 West Campbell Road, Richardson, TX 75080-3021 (United States)

    2012-06-01

    The synthesis of nanosized hafnium oxide by the polymerized complex derived sol-gel method is reported. The structural and morphological characterization of the HfO{sub 2} was carried out by X-ray diffraction and scanning electron microscopy. The surface of hafnium oxide nanoparticles was modified by capping with oleic acid. The nanoparticle surface area was measured by the gas adsorption technique in order to determine the minimal amount of oleic acid needed to obtain a uniform coverage of the hafnium oxide. The existence of organic layer can be confirmed by Fourier transform spectroscopy, solid state nuclear magnetic resonance spectroscopy, thermal gravimetric analysis and transmission electron microscopy. The FTIR and solid state NMR results reveal that oleic acid is chemisorbed as a carboxylate onto the HfO{sub 2} nanoparticle surface and confirm the formation of a monomolecular layer of oleic acid surrounding the HfO{sub 2}. The cover density of oleic acid on the HfO{sub 2} increases with the amount of oleic acid used to modify the nanoparticles and the surface properties of HfO{sub 2} nanoparticles modified with oleic acid change from hydrophilic to hydrophobic.

  16. Solid phase syntheses of oligoureas

    Energy Technology Data Exchange (ETDEWEB)

    Burgess, K.; Linthicum, D.S.; Russell, D.H.; Shin, H.; Shitangkoon, A.; Totani, R.; Zhang, A.J.; Ibarzo, J. [Texas A& M Univ., College Station, TX (United States)

    1997-02-19

    Isocyanates 7 were formed from monoprotected diamines 3 or 6, which in turn can be easily prepared from commercially available N-BOC- or N-FMOC-protected amino acid derivatives. Isocyanates 7, formed in situ, could be coupled directly to a solid support functionalized with amine groups or to amino acids anchored on resins using CH{sub 2}Cl{sub 2} as solvent and an 11 h coupling time at 25 {degree}C. Such couplings afforded peptidomimetics with an N-phthaloyl group at the N-terminus. The optimal conditions identified for removal of the N-phthaloyl group were to use 60% hydrazine in DMF for 1-3 h. Several sequences of amino acids coupled to ureas (`peptidic ureas`) and of sequential urea units (`oligoureas`) were prepared via solid phase syntheses and isolated by HPLC. Partition coefficients were measured for two of these peptidomimetics, and their water solubilities were found to be similar to the corresponding peptides. A small library of 160 analogues of the YGGFL-amide sequence was prepared via Houghten`s tea bag methodology. This library was tested for binding to the anti-{beta}-endorphin monoclonal antibody. Overall, this paper describes methodology for solid phase syntheses of oligourea derivatives with side chains corresponding to some of the protein amino acids. The chemistry involved is ideal for high-throughput syntheses and screening operations. 51 refs., 3 figs., 2 tabs.

  17. Two isosteric fluorinated derivatives of the powerful glucosidase inhibitors1-deoxynojirimycin and 2,5-dideoxy-2,5-imino-D-mannitol: Syntheses and glycosidase-inhibitory activities of 1,2,5-trideoxy-2-fluoro-1,5-imino-D-glucitol and of 1,2,5-trideoxy-1-fluoro-2,5-imino-D-mannitol

    DEFF Research Database (Denmark)

    Andersen, Søren Møller; Ebner, Michael; Ekhart, Christian W.

    1997-01-01

    ,5-imino-D-mannitol, were synthesised featuring glucose isomerase-catalysed aldose-ketose interconvertion reactions as the key steps of the syntheses.Results of inhibition studies conducted with these compounds and previously obtained deoxyfluoro derivatives of 1-deoxynojirimycin, employing glucosidases...

  18. Explaining Synthesized Software

    Science.gov (United States)

    VanBaalen, Jeffrey; Robinson, Peter; Lowry, Michael; Pressburger, Thomas; Lau, Sonie (Technical Monitor)

    1998-01-01

    Motivated by NASA's need for high-assurance software, NASA Ames' Amphion project has developed a generic program generation system based on deductive synthesis. Amphion has a number of advantages, such as the ability to develop a new synthesis system simply by writing a declarative domain theory. However, as a practical matter, the validation of the domain theory for such a system is problematic because the link between generated programs and the domain theory is complex. As a result, when generated programs do not behave as expected, it is difficult to isolate the cause, whether it be an incorrect problem specification or an error in the domain theory. This paper describes a tool we are developing that provides formal traceability between specifications and generated code for deductive synthesis systems. It is based on extensive instrumentation of the refutation-based theorem prover used to synthesize programs. It takes augmented proof structures and abstracts them to provide explanations of the relation between a specification, a domain theory, and synthesized code. In generating these explanations, the tool exploits the structure of Amphion domain theories, so the end user is not confronted with the intricacies of raw proof traces. This tool is crucial for the validation of domain theories as well as being important in everyday use of the code synthesis system. It plays an important role in validation because when generated programs exhibit incorrect behavior, it provides the links that can be traced to identify errors in specifications or domain theory. It plays an important role in the everyday use of the synthesis system by explaining to users what parts of a specification or of the domain theory contribute to what pieces of a generated program. Comments are inserted into the synthesized code that document these explanations.

  19. Widely tunable THz synthesizer

    Science.gov (United States)

    Hindle, F.; Mouret, G.; Eliet, S.; Guinet, M.; Cuisset, A.; Bocquet, R.; Yasui, T.; Rovera, D.

    2011-09-01

    The generation of cw-THz radiation by photomixing is particularly suited to the high resolution spectroscopy of gases; nevertheless, until recently, it has suffered from a lack of frequency metrology. Frequency combs are a powerful tool that can transfer microwave frequency standards to optical frequencies and a single comb has permitted accurate (10-8) THz frequency synthesis with a limited tuning range. A THz synthesizer composed of three extended cavity laser diodes phase locked to a frequency comb has been constructed and its utility for high resolution gas phase spectroscopy demonstrated. The third laser diode allows a larger tuning range of up to 300 MHz to be achieved without the need for large frequency excursions, while the frequency comb provides a versatile link to be established from any traceable microwave frequency standard. The use of a single frequency comb as a reference for all of the cw-lasers eliminates the dependency of synthesized frequency on the carrier envelope offset frequency. This greatly simplifies the frequency comb stabilization requirements and leads to a reduced instrument complexity.

  20. Method for synthesizing HMX

    Science.gov (United States)

    McGuire, Raymond R.; Coon, Clifford L.; Harrar, Jackson E.; Pearson, Richard K.

    1984-01-01

    A method and apparatus for electrochemically synthesizing N.sub.2 O.sub.5 cludes oxidizing a solution of N.sub.2 O.sub.4 /HNO.sub.3 at an anode, while maintaining a controlled potential between the N.sub.2 O.sub.4 /HNO.sub.3 solution and the anode. A potential of about 1.35 to 2.0 V vs. SCE is preferred, while a potential of about 1.80 V vs. SCE is most preferred. Thereafter, the N.sub.2 O.sub.5 is reacted with either 1.5-diacetyl-3,7-dinitro-1,3,5,7-tetraazacyclooctane (DADN) or 1,3,5,7-tetraacetyl-1,3,5,7-tetraazacyclooctane (TAT) to form cyclotetramethylenetetraamine (HMX).

  1. Design of geometry, synthesis, spectroscopic (FT-IR, UV/Vis, excited state, polarization) and anisotropy (thermal conductivity and electrical) properties of new synthesized derivatives of (E,E)-azomethines in colored stretched poly (vinyl alcohol) matrix

    Science.gov (United States)

    Shahab, Siyamak; Sheikhi, Masoome; Filippovich, Liudmila; Dikusar, Evgenij; Yahyaei, Hooriye; Kumar, Rakesh; Khaleghian, Mehrnoosh

    2018-04-01

    In the present work, the molecular structures of two new azomethine dyes: have been predicted and investigated using Density Functional Theory (DFT) in dimethylformamide (DMF). The geometries of the azomethine dyes were optimized by B3LYP/6-31+G* level of theory. The electronic spectra of these azomethine dyes in a DMF solvent was carried out by using TD-B3LYP/6-31+G* method. After quantum-chemical calculations two new azomethine dyes for optoelectronic applications were synthesized. FT-IR spectra of the title compounds are recorded and discussed. The computed absorption spectral data of the azomethine dyes are in good agreement with the experimental data, thus allowing an assignment of the UV/Vis spectra. On the basis of polyvinyl alcohol (PVA) and the new synthesized azomethine dyes polarizing films for visible region of spectrum were developed. The main optical parameters of the polarizing PVA-films (Transmittance, Polarization Efficiency and Dichroic Ratio) have been measured and discussed. Anisotropy of thermal and electrical conductivity of the PVA-films have been studied and explained.

  2. Syntheses, Protonation Constants and Antimicrobial Activity of 2 ...

    African Journals Online (AJOL)

    carboxaldehyde and N-alkylimidazole-2-methanol derivatives [alkyl = benzyl, methyl, ethyl, propyl, butyl, heptyl, octyl and decyl] have been synthesized and the protonation constants determined. The antimicrobial properties of the compounds were tested ...

  3. New natural product -an efficient antimicrobial applications of new newly synthesized pyrimidine derivatives by the electrochemical oxidation of hydroxyl phenol in the presence of 2-mercapto-6-(trifluoromethyl) pyrimidine-4-ol as nucleophile.

    Science.gov (United States)

    Khan, Zia Ul Haq; Khan, Amjad; Wan, Pingyu; Khan, Arif Ullah; Tahir, Kamran; Muhammad, Nawshad; Khan, Faheem Ullah; Shah, Hidayat Ullah; Khan, Zia Ullah

    2018-05-01

    Some new pyrimidine derivatives have been synthesised by electrochemical oxidation of catechol (1a) in the existence of 2-mercapto-6-(trifluoromethyl) pyrimidine-4-ol (3) as a nucleophile in aqueous solution using Cyclic Voltammetric and Controlled Potential Coulometry. The catechol has been oxidised to o-quinone through electrochemical method and participative in Michael addition reaction, leading to the development of some new pyrimidine derivatives. The products were achieved in good yield with high pureness. The mechanism of the reaction has been conformed from the Cyclic Voltammetric data and Controlled Potential Coulometry. After purification, the compounds were characterised using modern techniques. The synthesised materials were screened for antimicrobial actions using Gram positive and Gram negative strain of bacteria. These new synthesised pyrimidine derivatives showed very good antimicrobial activity.

  4. Syntheses, structures, electrochemistry and catalytic oxidation degradation of organic dyes of two new coordination polymers derived from Cu(II) and Mn(II) and 1-(tetrazo-5-yl)-4-(triazo-1-yl)benzene

    Energy Technology Data Exchange (ETDEWEB)

    Song, Ming; Mu, Bao; Huang, Ru-Dan, E-mail: huangrd@bit.edu.cn

    2017-02-15

    Two new coordination polymers (CPs), namely, [Cu{sub 2}(ttbz)(H{sub 2}btc){sub 2}(OH)]{sub n} (1) and [Mn(ttbz){sub 2}(H{sub 2}O){sub 2}]{sub n} (2) (Httbz =1-(tetrazo-5-yl)-4-(triazo-1-yl)benzene, H{sub 3}btc =1,3,5-benzenetricarboxylic acid), have been hydrothermally synthesized and structurally characterized. Complex 1 exhibits a (3,5,5,5)-connected 2D layer with a Schläfli symbol of (3·4{sup 2})(3·4{sup 4}0.5{sup 2}0.6{sup 3})(3{sup 2}0.4{sup 4}0.5{sup 2}0.6{sup 2})(3{sup 2}0.4{sup 4}0.5{sup 3}0.6), in which the ttbz{sup -} ligand can be described as μ{sub 5}-bridge, linking Cu(II) ions into a 2D layer and H{sub 2}btc{sup -} ions play a supporting role in complex 1. The ttbz{sup -} ligand in complex 2 represents the bridging coordination mode, connecting two Mn(II) ions to form the infinite 1D zigzag chains, respectively, which are further connected by two different types of hydrogen bonds to form a 3D supramolecular. Furthermore, catalytic oxidation activities toward organic dyes and electrochemical behaviors of the title complexes have been investigated at room temperature in aqueous solutions, indicating these complexes may be applicable to color removal in a textile wastewater stream and practical applications in areas of electrocatalytic reduction toward nitrite, respectively. - Graphical abstract: Two new coordination polymers based on different structural characteristics have been hydrothermally synthesized by the mixed ligands. The catalytic oxidation activities toward organic dyes and electrochemical behaviors of the title complexes have been investigated. - Highlights: • The organic ligand containing the tetrazolyl group and triazolyl group with some advantages has been used. • Two new coordination polymers with different structural characteristics has been discussed in detail. • Catalytic oxidation activities toward organic dyes and electrochemical behaviors of the title complexes have been investigated.

  5. Formulation and in vitro release evaluation of newly synthesized palm kernel oil esters-based nanoemulsion delivery system for 30% ethanolic dried extract derived from local Phyllanthus urinaria for skin antiaging

    Directory of Open Access Journals (Sweden)

    Mahdi ES

    2011-10-01

    Full Text Available Elrashid Saleh Mahdi1, Azmin Mohd Noor1, Mohamed Hameem Sakeena1, Ghassan Z Abdullah1, Muthanna F Abdulkarim1, Munavvar Abdul Sattar2 1Department of Pharmaceutical Technology, 2Department of Physiology, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Pulau Pinang, Malaysia Background: Recently there has been a remarkable surge of interest about natural products and their applications in the cosmetic industry. Topical delivery of antioxidants from natural sources is one of the approaches used to reverse signs of skin aging. The aim of this research was to develop a nanoemulsion cream for topical delivery of 30% ethanolic extract derived from local Phyllanthus urinaria (P. urinaria for skin antiaging. Methods: Palm kernel oil esters (PKOEs-based nanoemulsions were loaded with P. urinaria extract using a spontaneous method and characterized with respect to particle size, zeta potential, and rheological properties. The release profile of the extract was evaluated using in vitro Franz diffusion cells from an artificial membrane and the antioxidant activity of the extract released was evaluated using the 2, 2-diphenyl-1-picrylhydrazyl (DPPH method. Results: Formulation F12 consisted of wt/wt, 0.05% P. urinaria extract, 1% cetyl alcohol, 0.5% glyceryl monostearate, 12% PKOEs, and 27% Tween® 80/Span® 80 (9/1 with a hydrophilic lipophilic balance of 13.9, and a 59.5% phosphate buffer system at pH 7.4. Formulation F36 was comprised of 0.05% P. urinaria extract, 1% cetyl alcohol, 1% glyceryl monostearate, 14% PKOEs, 28% Tween® 80/Span® 80 (9/1 with a hydrophilic lipophilic balance of 13.9, and 56% phosphate buffer system at pH 7.4 with shear thinning and thixotropy. The droplet size of F12 and F36 was 30.74 nm and 35.71 nm, respectively, and their nanosizes were confirmed by transmission electron microscopy images. Thereafter, 51.30% and 51.02% of the loaded extract was released from F12 and F36 through an artificial cellulose membrane

  6. SYNTHESES, SPECTROSCOPIC AND MAGNETIC PROPERTIES ...

    African Journals Online (AJOL)

    Preferred Customer

    SYNTHESES, SPECTROSCOPIC AND MAGNETIC PROPERTIES OF. POLYSTYRENE-ANCHORED COORDINATION COMPOUNDS OF. THIAZOLIDINONE. Dinesh Kumar1, Amit Kumar2* and Durga Dass3. 1Department of Chemistry, National Institute of Technology, Kurukshetra 136119, Haryana,. India. 2Department of ...

  7. Fully automated parallel oligonucleotide synthesizer

    Czech Academy of Sciences Publication Activity Database

    Lebl, M.; Burger, Ch.; Ellman, B.; Heiner, D.; Ibrahim, G.; Jones, A.; Nibbe, M.; Thompson, J.; Mudra, Petr; Pokorný, Vít; Poncar, Pavel; Ženíšek, Karel

    2001-01-01

    Roč. 66, č. 8 (2001), s. 1299-1314 ISSN 0010-0765 Institutional research plan: CEZ:AV0Z4055905 Keywords : automated oligonucleotide synthesizer Subject RIV: CC - Organic Chemistry Impact factor: 0.778, year: 2001

  8. Synthesis and evaluation of new organic and phosphorous derivatives against ionizing radiation: study of the in vitro mechanism of action; Synthese et evaluation de nouveaux composes organiques et phosphores contre les effets des rayonnements ionisants. Etude de leur mecanisme d'action in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Prouillac, C

    2006-10-15

    This work falls under a research program. The aim was to synthesize new organic phosphorylated compounds having an interesting radio pharmacological activity without toxicity. That is why, we carried out the synthesis of new benzothiazole and thiadiazole N-substituted derivatives as thiols, amino thiols, acids thio-sulfonic and phosphoro thioates. All these compounds were characterized by NMR (proton, carbon, phosphorus, 2D), by mass spectrometry, elementary analyzes and for some of them by diffraction of x-rays. The activity of the majority of them was evaluated by in vitro tests. The experimental results were confirmed by theoretical study: the aim of D.F.T. calculation was the study of the mechanism of capture of the free radicals by our compounds. In addition, a study of relation structure activity (Q.S.A.R.) was carried out. Our results allow us to create a model making it possible to establish structure-activity relationship. (author)

  9. Squid Giant Axons Synthesize NF Proteins.

    Science.gov (United States)

    Crispino, Marianna; Chun, Jong Tai; Giuditta, Antonio

    2018-04-01

    Squid giant axon has been an excellent model system for studying fundamental topics in neurobiology such as neuronal signaling. It has been also useful in addressing the questions of local protein synthesis in the axons. Incubation of isolated squid giant axons with [ 35 S]methionine followed by immunoprecipitation with a rabbit antibody against all squid neurofilament (NF) proteins demonstrates the local synthesis of a major 180 kDa NF protein and of several NF proteins of lower molecular weights. Their identification as NF proteins is based on their absence in the preimmune precipitates. Immunoprecipitates washed with more stringent buffers confirmed these results. Our data are at variance with a recent study based on the same experimental procedure that failed to visualize the local synthesis of NF proteins by the giant axon and thereby suggested their exclusive derivation from nerve cell bodies (as reported by Gainer et al. in Cell Mol Neurobiol 37:475-486, 2017). By reviewing the pertinent literature, we confute the claims that mRNA translation is absent in mature axons because of a putative translation block and that most proteins of mature axons are synthesized in the surrounding glial cells. Given the intrinsic axonal capacity to synthesize proteins, we stress the glial derivation of axonal and presynaptic RNAs and the related proposal that these neuronal domains are endowed with largely independent gene expression systems (as reported by Giuditta et al. in Physiol Rev 88:515-555, 2008).

  10. Synthesis and complexation properties towards uranyl cation of carboxylic acid derivatives of p-tert-butyl-calix[6]arene; Synthese et proprietes complexantes vis-a-vis de l'ion uranyle de derives carboxyliques du p-tert-butyl-calix[6]arene

    Energy Technology Data Exchange (ETDEWEB)

    Souane, R

    2005-03-15

    In the fuel reprocessing plants radioactive metals, and more particularly, uranium in UO{sub 2}{sup 2+} form in the various installations, have many varied physico-chemical forms and there is a risk of exposure and internal contamination in the nuclear industry. It is necessary to exert a medical control to ensure the protection of the health of the workers. This medical control is done by dosing uranyl cation in the urine of the exposed people. This work forms part of this context. Indeed, we prepared a ligand able to complex the ion uranyl and which is also to be grafted on a solid support. In the family of calixarenes, the calix[6]arenes functionalized by three or four carboxylic functions were selected like chelating molecules of the ion uranyl. The properties of complexation of these calixarenes were studied by potentiometry in methanol, under these conditions balances of protonation and complexation were determined and the constant partners were obtained using the Hyperquad program. We synthesized tri-carboxylic calix[6]arenes comprising of the groupings nitro (NO{sub 2}) in para position of phenol in order to see the influence of a substitution in para position on the complexation. We also synthesized calix[6]arenes tetra-carboxylic in order to show the role of an additional carboxylic acid grouping. The potentiometric study determined thermodynamic parameters of protonation and complexation of carboxylic calix[6]arenes. The results of the complexation highlighted which complex UO{sub 2}L corresponding to the ligand para-tert-butyl-calix[6]arene tetra-acid is more stable than that corresponding to the ligand mono-nitro calix[6]arene tri-acid ({delta}log{beta}110 = 4.3), and than the effect of the groupings nitro in para position has low influence on the complexation of UO{sub 2}{sup 2+}. This makes it possible to consider as possible the grafting of the calix[6]arenes which one knows the behaviour of trapping. To this end we synthesized the ligand 23

  11. Information Retrieval for Ecological Syntheses

    Science.gov (United States)

    Bayliss, Helen R.; Beyer, Fiona R.

    2015-01-01

    Research syntheses are increasingly being conducted within the fields of ecology and environmental management. Information retrieval is crucial in any synthesis in identifying data for inclusion whilst potentially reducing biases in the dataset gathered, yet the nature of ecological information provides several challenges when compared with…

  12. Highly Stable Foams from Block Oligomers Synthesized by Enzymatic Reactions

    NARCIS (Netherlands)

    Sagis, L.M.C.; Boeriu, C.G.; Frissen, A.E.; Schols, H.A.; Wierenga, P.A.

    2008-01-01

    We have synthesized a new amphiphilic block oligomer by the enzymatic linking of a fatty acid (lauric acid) to a fructan oligomer (inulin) and tested the functionality of this carbohydrate derivative in foam stabilization. The structure of the modified oligosaccharide was found to be

  13. Catalytic method for synthesizing hydrocarbons

    Science.gov (United States)

    Sapienza, R.S.; Sansone, M.J.; Slegeir, W.A.R.

    A method for synthesizing hydrocarbons from carbon monoxide and hydrogen by contacting said gases with a slurry of a catalyst composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants.

  14. Method of synthesizing tungsten nanoparticles

    Science.gov (United States)

    Thoma, Steven G; Anderson, Travis M

    2013-02-12

    A method to synthesize tungsten nanoparticles has been developed that enables synthesis of nanometer-scale, monodisperse particles that can be stabilized only by tetrahydrofuran. The method can be used at room temperature, is scalable, and the product concentrated by standard means. Since no additives or stabilizing surfactants are required, this method is particularly well suited for producing tungsten nanoparticles for dispersion in polymers. If complete dispersion is achieved due to the size of the nanoparticles, then the optical properties of the polymer can be largely maintained.

  15. Enzymatically-Catalyzed Polymerization (ECP)- Derived Polymer Electrolyte for Rechargeable Li-Ion Batteries

    National Research Council Canada - National Science Library

    Chua, David

    1998-01-01

    Report developed under SBIR contract covers the syntheses and electrochemical characterizations of novel polymer electrolytes derived from compounds synthesized via enzyme-catalyzed polymerization(ECP) techniques...

  16. Essential oils-oriented fenvalerate analogues: syntheses, characterization and biological evaluation

    International Nuclear Information System (INIS)

    Su, H.; Li, H.

    2016-01-01

    A series of essential oils oriented ester derivatives have been designed, synthesized and characterized based on the skeleton of fenvalerate. The preliminary bioassay results indicated that some of the newly synthesized compounds showed better insecticidal activities against Pyrausta nubilalis and Heliothis armigera than that of the control trans-prallethrin chloride. (author)

  17. In vitro Anti-Leishmania Activity and Safety of Newly Synthesized ...

    African Journals Online (AJOL)

    In vitro Anti-Leishmania Activity and Safety of Newly Synthesized Thiazolo Pyrimidine Derivatives Augmented with Interleukine-12 (IL-12) in BALB/c Mice Experimentally- Infected with Cutaneous Leishmaniasis.

  18. Synthese de champs sonores adaptative

    Science.gov (United States)

    Gauthier, Philippe-Aubert

    La reproduction de champs acoustiques est une approche physique au probleme technologique de la spatialisation sonore. Cette these concerne l'aspect physique de la reproduction de champs acoustiques. L'objectif principal est l'amelioration de la reproduction de champs acoustiques par "synthese de champs acoustiques" ("Wave Field Synthesis", WFS), une approche connue, basee sur des hypotheses de champ libre, a l'aide du controle actif par l'ajout de capteurs de l'erreur de reproduction et d'une boucle fermee. Un premier chapitre technique (chapitre 4) expose les resultats d'appreciation objective de la WFS par simulations et mesures experimentales. L'effet indesirable de la salle de reproduction sur les qualites objectives de la WFS fut illustre. Une premiere question de recherche fut ensuite abordee (chapitre 5), a savoir s'il est possible de reproduire des champs progressifs en salle dans un paradigme physique de controle actif: cette possibilite fut prouvee. L'approche technique privilegiee, "synthese de champs adaptative" ("Adaptive Wave Field Synthesis" [AWFS]), fut definie, puis simulee (chapitre 6). Cette approche d'AWFS comporte une originalite en controle actif et en reproduction de champs acoustiques: la fonction cout quadratique representant la minimisation des erreurs de reproduction inclut une regularisation de Tikhonov avec solution a priori qui vient de la WFS. L'etude de l'AWFS a l'aide de la decomposition en valeurs singulieres (chapitre 7) a permis de comprendre les mecanismes propres a l'AWFS. C'est la deuxieme principale originalite de la these. L'algorithme FXLMS (LMS et reference filtree) est modifie pour l'AWFS (chapitre 8). Le decouplage du systeme par decomposition en valeurs singulieres est illustre dans le domaine du traitement de signal et l'AWFS basee sur le controle independant des modes de rayonnement est simulee (chapitre 8). Ce qui constitue la troisieme originalite principale de cette these. Ces simulations du traitement de signal

  19. Mechanochemically Driven Syntheses of Boride Nanomaterials

    Science.gov (United States)

    Blair, Richard G.

    Solid state metathesis reactions have proven to be a viable route to the production of unfunctionalized nanomaterials. However, current implementations of this approach are limited to self-propagating reactions. We have been investigating mechanically driven metathesis reactions. The use of high-energy ball mills allows control of crystallite sizes without the use of a capping group. Reinforcement materials with crystallite sizes on the order of 5-30 nm can be produced in such a manner. Borides are of particular interest due to their strength, high melting point, and electrical conductivity. The ultimate goal of this work is to prepare oxide and capping group-free nanoparticles suitable for incorporation in thermoelectric, polymer, and ceramic composites. Ultimately this work will facilitate the production of improved thermoelectric materials that will provide robust, deployable, power generation modules to supplement or replace fuel cell, Stirling, and battery-derived power sources. It will also result in scalable, bulk syntheses of tough, refractory, conductive nanomaterials for polymer composites with improved electrical properties, ceramic composites with enhanced fracture toughness, and composites with enhanced neutron reflectance and/or absorbance.

  20. Syntheses of surfactants from oleochemical epoxides

    Directory of Open Access Journals (Sweden)

    Warwel Siegfried

    2001-01-01

    Full Text Available Sugar-based surfactants were obtained in good yields (up to 100% under mild conditions (70°C, methanol or mixtures of methanol and water by ring-opening of terminal epoxides with aminopolyols, derived from glucose. Reaction of N-methyl glucamine with epoxides from even-numbered C4-C18 alpha-olefins or from terminal unsaturated fatty acid methyl esters leads to linear products, while corresponding reactions with N-dodecyl glucamine or glucamine yield surfactants with different Y-structures. Products obtained by conversion of omega-epoxy fatty acid methyl esters were saponificated with NaOH or hydrolyzed enzymatically to sodium salts or free acids respectively, which are amphoteric surfactants. Studies of the surfactants at different pH-values demonstrate different surface active properties in aqueous solutions. Critical micelle concentrations (c.m.c. in a range between 2 and 500mg/l and surface tensions of 25-40mN/m were measured for several of the synthesized sugar-based surfactants. The ring-opening products are rather poor foamers, whereas some of the corresponding hydrobromides show good foaming properties.

  1. Perception of Paralinguistic Traits in Synthesized Voices

    DEFF Research Database (Denmark)

    Baird, Alice Emily; Hasse Jørgensen, Stina; Parada-Cabaleiro, Emilia

    the paralinguistic traits of the synthesized voice. Using a corpus of 13 synthesized voices, constructed from acoustic concatenative speech synthesis, we assessed the response of 23 listeners from differing cultural backgrounds. Evaluating if the perception shifts from the known ground–truths, we asked listeners......Along with the rise of artificial intelligence and the internet-of-things, synthesized voices are now common in daily–life, providing us with guidance, assistance, and even companionship. From formant to concatenative synthesis, the synthesized voice continues to be defined by the same traits we...

  2. Synthesizing Knowledge in Design Research

    DEFF Research Database (Denmark)

    Piirainen, Kalle A.

    2016-01-01

    attention is paid to the question of how practice-based or problem-driven design research processes can be rigorous and yield contributions to knowledge. The main argument in this chapter is that a key to knowledge synthesis and scientific contribution is setting explicit design propositions......The chapter discusses knowledge synthesis in design research, bringing together the perspectives of experimental design research, or Research in Design Context that is treated extensively elsewhere in this book, and Design Inclusive Research as well as Practice-based Design Research. Specific...... that are instantiated within design artefacts, and evaluated rigorously. The chapter starts with a discussion of knowledge creation and synthesis within design research.Following this, the chapter moves on to focus on setting a methodological framework for deriving design propositions. Lastly the chapter elaborates...

  3. Composites comprising biologically-synthesized nanomaterials

    Science.gov (United States)

    Curran, Seamus; Dias, Sampath; Blau, Werner; Wang, Jun; Oremland, Ronald S; Baesman, Shaun

    2013-04-30

    The present disclosure describes composite materials containing a polymer material and a nanoscale material dispersed in the polymer material. The nanoscale materials may be biologically synthesized, such as tellurium nanorods synthesized by Bacillus selenitireducens. Composite materials of the present disclosure may have optical limiting properties and find use in optical limiting devices.

  4. Perception of Paralinguistic Traits in Synthesized Voices

    DEFF Research Database (Denmark)

    Baird, Alice Emily; Hasse Jørgensen, Stina; Parada-Cabaleiro, Emilia

    2017-01-01

    Along with the rise of artificial intelligence and the internet-of-things, synthesized voices are now common in daily–life, providing us with guidance, assistance, and even companionship. From formant to concatenative synthesis, the synthesized voice continues to be defined by the same traits we...

  5. Enzymatically Synthesized Feruloyl Dioleoylglycerol: Antioxidant Behavior and Position in Phospholipid Vesicles

    Science.gov (United States)

    Ferulic acid and its ester derivatives are known to be effective antioxidants and as such have been investigated as a potential antioxidant agent for cosmetic and pharmaceutical uses. Using immobilized Candida antarctica lipase B we synthesized ferulic acid lipophilic derivatives from vegetable oil...

  6. Studies on the Alkaloids of the Calycanthaceae and Their Syntheses

    Directory of Open Access Journals (Sweden)

    Jin-Biao Xu

    2015-04-01

    Full Text Available Plants of the Calycanthaceae family, which possesses four genera and about 15 species, are mainly distributed in China, North America and Australia. Chemical studies on the Calycanthaceae have led to the discovery of about 14 alkaloids of different skeletons, including dimeric piperidinoquinoline, dimeric pyrrolidinoindoline and/or trimeric pyrrolidinoindolines, which exhibit significant anti-convulsant, anti-fungal, anti-viral analgesic, anti-tumor, and anti-melanogenesis activities. As some of complex tryptamine-derived alkaloids exhibit promising biological activities, the syntheses of these alkaloids have also been a topic of interest in synthetic chemistry during the last decades. This review will focus on the structures and total syntheses of these alkaloids.

  7. Syntheses, molecular and crystalline architectures, and ...

    Indian Academy of Sciences (India)

    Syntheses, molecular and crystalline architectures, and luminescence behaviour of terephthalate bridged heptacoordinated dinuclear lead(II) complexes containing a pentadentate N-donor Schiff base. SUBHASIS ROYa, SOMNATH CHOUBEYa, SUMITAVA KHANa, KISHALAY BHARa,. PARTHA MITRAb and BARINDRA ...

  8. Synthese en chemotherapeutisch onderzoek van sulfanilamidopyrimidinen

    NARCIS (Netherlands)

    Grevenstuk, Anton Bernard

    1942-01-01

    In order to investigate the influence of substitution in the pyrimidine nucleous on the activity of the three isomeric sulfanilamidopyrimidines (2, 5 and 6), a number of substituted sulfanilamidopyrimidines were synthesized and tested on chemotherapeutic activity. ... Zie: Summary

  9. CAMAC programmable-control frequency synthesizer

    International Nuclear Information System (INIS)

    Yumaguzin, T.Kh.; Vyazovkin, D.E.; Nazirov, Eh.P.; Tuktarov, R.F.

    1989-01-01

    Synthesizer allows to set frequency with 0.015% accuracy and to scan it with variable step. Frequency controlled divider with further summing-up of divided frequency with fundamental one is used in synthesizer, and it has allowed to use digit of the input code and to obtain 3-4 MHz frequency range. Variation of operation flowsheet in the other frequency range is possible. K-155 and K-531 series microcircuits were used during development

  10. Raman assisted lightwave synthesized frequency sweeper

    DEFF Research Database (Denmark)

    Pedersen, Anders Tegtmeier; Rottwitt, Karsten

    2010-01-01

    We present a Lightwave Synthesized Frequency Sweeper comprising a Raman amplifier for loss compensation. The generated pulse train contains 123 pulses and has a flat signal level as well as a low noise level.......We present a Lightwave Synthesized Frequency Sweeper comprising a Raman amplifier for loss compensation. The generated pulse train contains 123 pulses and has a flat signal level as well as a low noise level....

  11. Psychoacoustic Analysis of Synthesized Jet Noise

    Science.gov (United States)

    Okcu, Selen; Rathsam, Jonathan; Rizzi, Stephen A.

    2013-01-01

    An aircraft noise synthesis capability is being developed so the annoyance caused by proposed aircraft can be assessed during the design stage. To make synthesized signals as realistic as possible, high fidelity simulation is required for source (e.g., engine noise, airframe noise), propagation and receiver effects. This psychoacoustic study tests whether the jet noise component of synthesized aircraft engine noise can be made more realistic using a low frequency oscillator (LFO) technique to simulate fluctuations in level observed in recordings. Jet noise predictions are commonly made in the frequency domain based on models of time-averaged empirical data. The synthesis process involves conversion of the frequency domain prediction into an audible pressure time history. However, because the predictions are time-invariant, the synthesized sound lacks fluctuations observed in recordings. Such fluctuations are hypothesized to be perceptually important. To introduce time-varying characteristics into jet noise synthesis, a method has been developed that modulates measured or predicted 1/3-octave band levels with a (<20Hz) LFO. The LFO characteristics are determined through analysis of laboratory jet noise recordings. For the aft emission angle, results indicate that signals synthesized using a generic LFO are perceived as more similar to recordings than those using no LFO, and signals synthesized with an angle-specific LFO are more similar to recordings than those synthesized with a generic LFO.

  12. Soft-Template-Synthesized Mesoporous Carbon for Oral Drug Delivery

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Dipendu [ORNL; Warren, Kaitlyn E [ORNL; Naskar, Amit K [ORNL

    2014-01-01

    Template-synthesized mesoporous carbons were successfully used in in vitro investigations of controlled delivery of three model drugs, captopril, furosemide, and ranitidine hydrochloride. Captopril and furosemide exhibited desorption kinetics over 30 40 h, and ranitidine HCl had a complete release time of 5 10 h. As evident from the slow release kinetics, we contend that our mesoporous carbon is an improved drug-delivery medium compared to state-of-the-art porous silica-based substrates. The mesoporous carbons, synthesized from phloroglucinol and lignin, a synthetic and a sustainable precursor, respectively, exhibit BET surface area of 200 400 m2 g-1 and pore volume of 0.2 0.6 cm3 g-1. The phloroglucinol-based carbon has narrower pore widths and higher pore volume than the lignin-derived counterpart and maintains a longer release time. Numerical modeling of the release kinetics data reveals that the diffusivities of all the drugs from lignin-based carbon media are of equivalent magnitude (10-22 to 10-24 m2 s-1). However, a tailored reduction of pore width in the sorbent reduces the diffusivity of smaller drug molecules (captopril) by an order of magnitude. Thus, engineered pore morphology in our synthesized carbon sorbent, along with its potential to tailor the chemistry of its interaction with sorbet, can be exploited for optimal delivery system of a preferred drug within its therapeutic level and below the level of toxicity.

  13. Biological activities of substituted trichostatic acid derivatives

    Indian Academy of Sciences (India)

    New substituted trichostatic acid derivatives have been synthesized and evaluated for their biological activities towards the H661 non-small lung cancer cell line. These syntheses were achieved by alkylation of propiophenones to introduce the side chain with a terminal precursor of hydroxamic acid and aminobenzamide ...

  14. Curcumin derivatives as HIV-1 protease inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Sui, Z.; Li, J.; Craik, C.S.; Ortiz de Montellano, P.R. [Univ. of California, San Francisco, CA (United States)

    1993-12-31

    Curcumin, a non-toxic natural compound from Curcuma longa, has been found to be an HIV-1 protease inhibitor. Some of its derivatives were synthesized and their inhibitory activity against the HIV-1 protease was tested. Curcumin analogues containing boron enhanced the inhibitory activity. At least of the the synthesized compounds irreversibly inhibits the HIV-1 protease.

  15. Effect of donor-acceptor chromophores on photophysical properties of newly synthesized pyrazolo-pyrrolo-pyrimidines (PPP).

    Science.gov (United States)

    Rote, Ramhari V; Shelar, Deepak P; Patil, Sandeep R; Shinde, Santosh S; Toche, Raghunath B; Jachak, Madhukar N

    2011-01-01

    Novel pyrazolo-pyrrolo-pyrimidine (PPP) derivatives having remarkable photophysical properties are designed with the help of theoretical semiempirical calculations. These compounds then synthesized successfully and studied effect of substituents on its photophysical properties.

  16. Novel Mannich-bases as Potential Anticonvulsants: Syntheses, Characterization and Biological Evaluation.

    Science.gov (United States)

    Keshari, Amit K; Tewari, Aseem; Verma, Shweta S; Saraf, Shailendra K

    2017-01-01

    Mannich bases are known to be an important pharmacophore or bioactive leads in the synthesis of various potential agents that have a variety of therapeutic activities like anticancer, antipsychotic, anticonvulsant, antimalarial, anti-inflammatory, antibacterial and so forth. Thus, in the present research, conjugation of moieties like 1,5-benzoxazepines and 1,5-benzothiazepines with secondary amines like piperazine, methyl piperazine and morpholine was carried out in a Mannich base with an anticipation of good anticonvulsant activity. Synthesis, characterization, structure activity relationship and anticonvulsant activity of the Mannich bases of 1,5-benzothiazepine and 1,5-benzoxazepine derivatives. All the derivatives were synthesized in three steps. In the first step, substituted 4-hydroxy chalconylbenzene was synthesized by the reaction of 4-hydroxyacetophenone and substituted benzaldehyde, in the presence of potassium hydroxide. In the second step, 2,3-dihydro- 1,5- benzothiazepines and 2,3-dihydro-1,5-benzoxazepines were synthesized by the reaction of 2- thio/aminophenol with chalcones in the presence of glacial acetic acid. In the third step, these compounds finally underwent Mannich reaction with different secondary amines to the respective title compounds. All the synthesized derivatives were characterised and evaluated for anticonvulsant activity using MES (Maximal Electroshock Induced Seizure) and INH (Isoniazide Induced Convulsion) models. The synthesized derivatives were found to be more active in the MES model than INH model, with phenytoin and diazepam being the standards respectively. Accordingly, the mode of action of the synthesized compounds may be similar to phenytoin. The methyl piperazine containing compound, at a dose of 30 mg/kg., was found to be the most active and promising compound in the series. The benzothiazepine derivatives showed better anticonvulsant activity than the benzoxazepines derivatives. Copyright© Bentham Science Publishers

  17. Novel bisstyryl derivatives of bakuchiol

    DEFF Research Database (Denmark)

    Reddy, Mallepally V; Thota, Niranjan; Sangwan, Payare L

    2010-01-01

    Novel bisstyryl derivatives of bakuchiol using Heck coupling reaction as the key step were synthesized and screened against a panel of six oral cavity pathogens for their antimicrobial activity. Four compounds (9-12) showed two to fourfold and four to eightfold better activity (MIC 0.25-16 microg...

  18. Therapeutic Versatility of Resveratrol Derivatives

    OpenAIRE

    Waqas Nawaz; Zhongqin Zhou; Sa Deng; Xiaodong Ma; Xiaochi Ma; Chuangang Li; Xiaohong Shu

    2017-01-01

    Resveratrol, a natural phytoalexin, exhibits a remarkable range of biological activities, such as anticancer, cardioprotective, neuroprotective and antioxidant properties. However, the therapeutic application of resveratrol was encumbered for its low bioavailability. Therefore, many researchers focused on designing and synthesizing the derivatives of resveratrol to enhance the bioavailability and the pharmacological activity of resveratrol. During the past decades, a large number of natural a...

  19. Synthesizing Smart Polymeric and Composite Materials

    Science.gov (United States)

    Gong, Chaokun

    ,1-phenylene)bismaleimide (MDPB). It showed the same healing ability as 2MEP4F while all starting materials are cheaper and commercially available. To further improve the mechanical strength of the PFA-MDPB healable polymer, epoxy as a strengthening component was mixed with PFA-MDPB healable polymer. The PFA, MDPB and epoxy composite polymers were further reinforced by carbon fiber as done with 2MEP4F matrix and the final composites were proved to have higher short beam shear strength than 2MEP4F while exhibiting a similar healing efficiency. Healable polymer MDPB (a two maleimide groups monomer) -- FGEEDR (a four furan groups monomer) was also designed and synthesized for transparent healable polymer. The MDPB-FGEEDR healable polymer was composited with silver nanowires (AgNWs) to afford healable transparent composite conductor. Razer blade cuts in the composite conductor could heal upon heating to recover the mechanical strength and electrical conductivity of the composite. The healing could be repeated for multiple times on the same cut location. The healing process was as fast as 3 minutes for conductivity to recover 97% of the original value. For electroactive polymer polypyrrole, the fast volume change upon electrical field change due to electrochemical oxidization or reduction was studied for actuation targeting toward a robotic application. The flexibility of polypyrrole was improved via copolymerization with pyrrole derivatives. Actuator devices are fabricated that more suitable for implantable medical device application than pyrrole homopolymer. The change of dipole re-orientation and thus dielectric constant of ferroelectric polymers and ceramics upon electrical field may be exploited for electrocaloric effect (ECE) and solid state refrigeration. For ferroelectric ceramics, we synthesized a series of Ba1-xSrxTiO3 nanoparticles with diameter ranging from 8-12 nm and characterized their dielectric and ferroelectric properties through hysteresis measurement. It was

  20. Concise total syntheses of (+/-)-strychnine and (+/-)-akuammicine.

    Science.gov (United States)

    Sirasani, Gopal; Paul, Tapas; Dougherty, William; Kassel, Scott; Andrade, Rodrigo B

    2010-05-21

    Concise total syntheses of Strychnos alkaloids strychnine (1) and akuammicine (2) have been realized in 13 and 6 operations, respectively. Key steps include (1) the vinylogous Mannich reaction; (2) a novel, sequential one-pot spirocyclization/intramolecular aza-Baylis-Hillman reaction; and (3) a Heck cyclization. The synthesis of 1 proceeds via the Wieland-Gumlich aldehyde (26).

  1. Ferromagnetic Behavior in Zinc Ferrite Nanoparticles Synthesized ...

    African Journals Online (AJOL)

    Zinc ferrite have been produced and used by humans since long time, however understanding of ZnFe2O4 as a nano structured materials is very useful in order to be used for technological applications. ZnFe2O4 structural, magnetic and electrical properties are different when synthesized using different techniques.

  2. Biosynthesis of silver nanoparticles synthesized by Aspergillus

    Indian Academy of Sciences (India)

    In the present study, biosynthesis of silver nanoparticles and its antioxidant, antimicrobial and cytotoxic activities were investigated. Silver nanoparticles were extracellularly synthesized using Aspergillus flavus and the formation of nanoparticles was observed after 72 h of incubation. The results recorded from colour ...

  3. nanoparticles synthesized by citrate precursor m

    African Journals Online (AJOL)

    user

    Abstract. Ni0.5M0.5Fe2O4 (M = Co, Cu) ferrite nanoparticles were synthesized using citrate precursor method. The citrate precursor was annealed at temperatures 400oC, 450oC, 500oC and 550oC. The annealed powders were characterized using X-ray diffractometer. (XRD) and vibrating sample magnetometer (VSM).

  4. Biological activities of synthesized silver nanoparticles from ...

    Indian Academy of Sciences (India)

    The C. halicacabum leaf extract synthesized AgNPs efficiency were tested against different bacterial pathogens MTCC-426 Proteus vulgaris, MTCC-2453 Pseudomonas aeruginosa, MTCC-96 Staphylococcus aureus, MTCC-441 Bacillus subtilis andMTCC-735 Salmonella paratyphi, and fungal pathogens Alternaria solani ...

  5. Syntheses of copper complexes of nicotinohydroxamic and ...

    African Journals Online (AJOL)

    Nicotinohydroxamic acid (NHA) and isonicotinohydroxamic acid (INHA) were synthesized, characterized by electronic and spectral studies,magnetic measurements and their pKa determined spectrophotometrically as 8.68 ± 0.02 in aqueous medium of 0.1mol dm-3 I=ionic strength. The composition of the complexes was ...

  6. Syntheses, molecular and crystalline architectures, and ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 125; Issue 4. Syntheses, molecular and crystalline architectures, and luminescence behaviour of terephthalate bridged heptacoordinated dinuclear lead(II) complexes containing a pentadentate N-donor Schiff base. Subhasis Roy Somnath Choubey Sumitava Khan ...

  7. Biological activities of synthesized silver nanoparticles

    Indian Academy of Sciences (India)

    The C. halicacabum leaf extract synthesized AgNPs efficiency were tested against different bacterial pathogens MTCC-426 Proteus vulgaris, MTCC-2453 Pseudomonas aeruginosa, MTCC-96 Staphylococcus aureus, MTCC-441 Bacillus subtilis andMTCC-735 Salmonella paratyphi, and fungal pathogens Alternaria solani ...

  8. Method and apparatus for synthesizing filamentary structures

    Science.gov (United States)

    Height, Murray J [Somerville, MA; Howard, Jack B [Winchester, MA; Vandersande, John B [Newbury, MA

    2008-02-26

    Method and apparatus for producing filamentary structures. The structures include single-walled nanotubes. The method includes combusting hydrocarbon fuel and oxygen to establish a non-sooting flame and providing an unsupported catalyst to synthesize the filamentary structure in a post-flame region of the flame. Residence time is selected to favor filamentary structure growth.

  9. Cytotoxicity of Nanoliposomal Cisplatin Coated with Synthesized ...

    African Journals Online (AJOL)

    Purpose: To evaluate the cytotoxicity of pegylated nanoliposomal cisplatin on human ovarian cancer cell line A2780CP. Methods: Synthesized methoxypolyethylene glycol (mPEG) propionaldehyde was characterized by 1Hnuclear magnetic resonance (1H-NMR) and Fourier transform infrared spectroscopy (FTIR) and used ...

  10. Syntheses, molecular and crystalline architectures, and ...

    Indian Academy of Sciences (India)

    Syntheses, molecular and crystalline architectures, and luminescence behaviour of terephthalate bridged heptacoordinated dinuclear lead(II) complexes containing a pentadentate N-donor Schiff base ... The complexes display intraligand (-*) fluorescence in the solid state and in DMF solutions at room temperature.

  11. Cytotoxicity of Nanoliposomal Cisplatin Coated with Synthesized ...

    African Journals Online (AJOL)

    Methods: Synthesized methoxypolyethylene glycol (mPEG) propionaldehyde was characterized by 1H- nuclear magnetic resonance (1H-NMR) and Fourier transform infrared spectroscopy (FTIR) and used as coating agent for the preparation of liposomal nanodrug formulation by reverse phase evaporation method.

  12. Biosynthesis of silver nanoparticles synthesized by Aspergillus ...

    Indian Academy of Sciences (India)

    In the present study, biosynthesis of silver nanoparticles and its antioxidant, antimicrobial and cytotoxic activities were investigated. Silver nanoparticles were extracellularly synthesized using Aspergillus flavus and the formation of nanoparticles was observed after 72 h of incubation. The results recorded from colour ...

  13. Synthese et caracterisation par spectroscopie infrarouge et ...

    African Journals Online (AJOL)

    ABSTRACT:- About six new Molybdato adducts of tin tetrahalide and tin(IV) organometallics have been synthesized and characterized. Their infrared and Mössbauer study allow us to suggest discrete structures with only one polydentate ligand or two types of ligands of different symmetries in the same adduct. KEYWORDS: ...

  14. Adsorption study of Pb 2 ions on nanosized SnO2, synthesized by ...

    Indian Academy of Sciences (India)

    Adsorption of Pb2+ ions on combustion derived nanosized SnO2 is studied. The as synthesized SnO2 and lead ions adsorbed SnO2 are characterized by X-ray diffraction (XRD), scanning electron micrograph (SEM), and infrared spectroscopic (IR) techniques. The eluent is characterized by atomic absorption spectroscopy ...

  15. Phosphorus-bridged ansa-metallocene complexes of titanium, zirconium, and hafnium: The syntheses and structures of [PhP(C{sub 5}Me{sub 4}){sub 2}]MX{sub 2} and [Ph(E)P(C{sub 5}Me{sub 4}){sub 2}]MX{sub 2} (E = O, S, Se) derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Shin, J.H.; Hascall, T.; Parkin, G. [Columbia Univ., New York, NY (United States). Dept. of Chemistry

    1999-01-04

    A series of phosphorus-bridged ansa-metallocene complexes of titanium, zirconium, and hafnium, [PhP(XC{sub 5}Me{sub 4}){sub 2}]MX{sub 2} and [Ph(E)P(C{sub 5}Me{sub 4}){sub 2}]MX{sub 2} (X = Cl, Me, CO, (Se{sub 3}){sub 0.5}; E = O, S, Se), has been synthesized. Structural characterization by X-ray diffraction indicates that, in comparison to their non-ansa counterparts (C{sub 5}Me{sub 5}){sub 2}MX{sub 2}, the cyclopentadienyl groups in phosphorus-bridged complexes are displaced from symmetric {eta}{sup 5}-coordination toward {eta}{sup 3}-coordination. Such {eta}{sup 3},{eta}{sup 3}-coordination creates more electrophilic metal centers than those in their permethylcyclopentadienyl counterparts, as judged by the {nu}(CO) stretching frequencies of the zirconium dicarbonyl complexes Cp{sup *}{sub 2}Zr(CO){sub 2} (1946 and 1853 cm{sup {minus}1}) and [PhP(C{sub 5}Me{sub 4}){sub 2}]Zr(CO){sub 2} (1959 and 1874 cm{sup {minus}1}).

  16. Enzymatic synthesizing of phytosterol oleic esters.

    Science.gov (United States)

    Pan, Xinxin; Chen, Biqiang; Wang, Juan; Zhang, Xinzhi; Zhul, Biyun; Tan, Tianwei

    2012-09-01

    A method of synthesizing the phytosterol esters from oleic acid and sterols was studied, using immobilized lipase Candida sp. 99-125 as catalyst. Molar ratio (oleic acid/phytosterols), temperature, reaction period, organic solvents, catalyst, and silica-gel drier were optimized, and the result showed that 93.4% of the sterols had been esterified under the optimal synthetic condition: the molar ratio of oleic acid/phytosterol is 1:1 in 10 mL iso-octane, immobilized lipase (w, 140% of the sterols), incubated in an orbital shaker (200 rpm) at a temperature of 45 °C for 24 h. The immobilized lipase could be reused for at least 13 times with limited loss of esterification activity. The conversion still maintained up to 86.6%. Hence, this developed process for synthesizing phytosterol esters could be considered as simple and low-energy consumption compared to existing chemical processes.

  17. Difference-Equation-Based Digital Frequency Synthesizer

    Directory of Open Access Journals (Sweden)

    Lu-Ting Ko

    2012-01-01

    Full Text Available This paper presents a novel algorithm and architecture for digital frequency synthesis (DFS. It is based on a simple difference equation. Simulation results show that the proposed DFS algorithm is preferable to the conventional phase-locked-loop frequency synthesizer and the direct digital frequency synthesizer in terms of the spurious-free dynamic range (SFDR and the peak-signal-to-noise ratio (PSNR. Specifically, the results of SFDR and PSNR are more than 186.91 dBc and 127.74 dB, respectively. Moreover, an efficient DFS architecture for VLSI implementation is also proposed, which has the advantage of saving hardware cost and power consumption.

  18. Syntheses and studies of organosilicon compounds

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Ren [Iowa State Univ., Ames, IA (United States)

    1999-02-12

    The syntheses of polycarbosilanes and polysilanes as silicon carbide ceramic precursors have been active research areas in the Barton Research Group. In this thesis, the work is focused on the preparation of polycarbosilanes and polysilanes as stoichiometric silicon carbide precursor polymers. The syntheses of the precursor polymers are discussed and the conversions of these precursors to silicon carbide via pyrolysis are reported. The XRD pattern and elemental analyses of the resulting silicon carbide ceramics are presented. Silicon monoxide is an important intermediate in the production of silicon metal. The existence of silicon monoxide in gap phase has been widely accepted. In the second part of this thesis, the generation of gaseous silicon monoxide in four different reactors and the reactions of gaseous silicon monoxide towards organic compounds are discussed.

  19. Biological activities of synthesized silver nanoparticles from ...

    Indian Academy of Sciences (India)

    ical scavenging activity was measured by the salicylic acid method [16]. The synthesized AgNPs solution at different concentrations (10 to 80 μg ml. −1. ) was dissolved in 1 ml of distilled water. One millilitre of AgNPs mixed with 1 ml of. 9 mM salicylic acid, 1 ml of 9 mM ferrous sulphate and 1ml of 9 mM hydrogen peroxide.

  20. Spurious in PLL-DDS frequency synthesizers

    Czech Academy of Sciences Publication Activity Database

    Kroupa, Věnceslav František; Štursa, Jarmil

    2002-01-01

    Roč. 2, č. 1 (2002), s. 48-51 ISSN 1335-8243. [Digital Signal Processing and Multimedia Communications DSP-MCOM 2001 /5./. Košice, 27.11.2001-29.11.2001] R&D Projects: GA ČR GA102/00/0958 Institutional research plan: CEZ:AV0Z2067918 Keywords : frequency synthesizers * phase locked loops * direct digital synthesis Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  1. Total syntheses of (-)-haemanthidine, (+)-pretazettine, and (+)-tazettine.

    Science.gov (United States)

    Baldwin, S W; Debenham, J S

    2000-01-27

    [structures: see text] The total syntheses of the amaryllidaceae alkaloids haemanthidine, pretazettine, and tazettine as optically pure enantiomers are reported. Using D-mannose as the starting material, the critical relative stereochemical relationships are established with an intramolecular nitrone-alkene cycloaddition reaction. The synthetic route leads successively to (-)-haemanthidine and then to (+)-pretazettine and (+)-tazettine, taking advantage of the well-established complex relationships among these three alkaloids.

  2. Hemoglobin derivatives

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003371.htm Hemoglobin derivatives To use the sharing features on this page, please enable JavaScript. Hemoglobin derivatives are altered forms of hemoglobin . Hemoglobin is ...

  3. Magnesioferrite synthesized from magnesian-magnetites

    Directory of Open Access Journals (Sweden)

    Marcelo Hidemassa Anami

    2014-02-01

    Full Text Available Magnesioferrite is an important mineral due to its use in different scientific fields and by the fact that the soil through the action of weathering, can be a source of nutrients essential for plant development by the fact that in the soil. Its use in pure form or associated with other minerals is only possible through the synthesis in laboratory conditions. This study aimed to synthesize magnesioferrite and hematite from magnesian-magnetite by a co-precipitation procedure. The methodology used is an adaptation of the method of synthesis of pure magnetite, partially replacing the soluble salts of iron with soluble magnesium salts in the proportion of 30.0 mol% of Fe for Mg. The characterization of the synthetic minerals used x-rays diffraction, total chemical analysis and mass specific magnetic susceptibility. The results showed that besides the magnesian-magnetite an unprecedented muskoxita was synthesized, which upon annealing was converted to magnesioferrite and hematite and in the proportion of 93.1% and 6.9% respectively. The isomorphous substitution of Fe for Mg enhanced the thermal stability of the ferrimagnetic mineral synthesized.

  4. dione derivatives

    Indian Academy of Sciences (India)

    MCF-7 (breast), U87 (glioma), HeLa (cervix), A549. (lung), A431 (vulvar) using MTT assay. The obtained inhibitory activity (IC50) of the synthesized com- pounds (12a–d and 13a–d) using 5-fluorouracil as standard are tabulated in Table S1 (in Supplementray. Information). The incubation of organic molecules on cancer cell.

  5. Characterization and magnetic properties of Nd{sub x}Bi{sub 1−x}Fe{sub 0.95}Co{sub 0.05}O{sub 3} nanopowders synthesized by combustion-derived method at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Hernández, N., E-mail: netzahualpille.hernandeznv@uanl.edu.mx [Centro de Innovación, Investigación y Desarrollo en Ingeniería y Tecnología, Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, Km. 10 de la nueva carretera al Aeropuerto Internacional de Monterrey, PIIT Monterrey, CP 66600 Apodaca, Nuevo León (Mexico); González-González, V.A.; Dzul-Bautista, I.B.; Cienfuegos-Pelaes, R.F. [Centro de Innovación, Investigación y Desarrollo en Ingeniería y Tecnología, Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, Km. 10 de la nueva carretera al Aeropuerto Internacional de Monterrey, PIIT Monterrey, CP 66600 Apodaca, Nuevo León (Mexico); Barandiaran, J.M.; Gutierréz, J. [BCMaterials and Universidad del País Vasco (UPV/EHU), Departamento de Electricidad y Electrónica, P.O Box 644, 48080 Bilbao (Spain); Hernández, T. [Facultad de Ciencias Químicas, Universidad Autónoma de Nuevo León, C.P. 66450 San Nicolás de los Garza, Nuevo León (Mexico); and others

    2015-03-01

    Nd{sub x}Bi{sub 1−x}Fe{sub 0.95}Co{sub 0.05}O{sub 3} (x=0, 0.05, 0.10, 0.15) nanopowders were prepared by a combustion-derived method. The Rietvelt fitting of the X-Ray diffraction data from the Nd{sub x}Bi{sub 1−x}Fe{sub 0.95}Co{sub 0.05}O{sub 3} (NBFCO) powders showed nanopowders with rhombohedral BiFeO{sub 3} crystalline structure (R3c) for x≤10 and a partial structural transition to orthorhombic phase (Pnma) for x=0.15. The differential thermal analysis and thermogravimetric analysis (DTA/TGA) showed a crystallization temperature of 180 °C. Transmission electronmicroscopy (TEM) images revealed that the NBFCO nanopowders were composed of fine particles under 60 nm. From Raman spectroscopy, a band of disordered anion lattice was observed at 653 cm{sup −1}. In spite of the antiferromagnetic nature of bulk BiFeO{sub 3}, the NBFCO nanopowders obtained displayed a ferromagnetic hysteresis loop, with coercivity about 0.1 T and remanent magnetization of 1.02–4.33 A m{sup 2}/kg were obtained at room temperature. This ferromagnetic behavior is due to increasing and uncompensated spins at the surface and the canted internal spin by the tilt of FeO{sub 6} octahedral units. We have developed a novel synthetic route for the preparation of ferromagnetic BFO-derived nanopowder materials by a surfactant-assisted combustion-derived method. - Highlights: • The structure of materials obtained is studied. • A new synthesis method was proposed to obtain ferrimagnetic–ferromagnetic BiFeO{sub 3} nanoparticles. • Synthesis temperature does not exceed 200 °C. • The obtained nanoparticles have sizes less than 52 nm.

  6. Biocompatibility of poly allylamine synthesized by plasma

    International Nuclear Information System (INIS)

    Colin, E.; Enriquez, M.A.; Olayo, M.G.; Cruz, G.J.; Morales, J.; Olayo, R.

    2007-01-01

    A study of the electric and hydrophilic properties of poly allylamine (PAI) synthesized by plasma whose structure contains N-H, C-H, C-O and O-H bonds is presented, that promote the biocompatibility with the human body. To study the PAI hydrolytic affinity, solutions of salt concentration similar to those of the human body were used. The results indicate that the solutions modify the charge balance in the surfaces reducing the hydrophobicity in the poly allylamine whose contact angle oscillates among 10 and 16 degrees and the liquid-solid surface tension between 4 and 8 dina/cm. (Author)

  7. Syntheses and electronic structures of decamethylmanganocenes

    International Nuclear Information System (INIS)

    Robbins, J.L.; Edelstein, N.M.; Cooper, S.R.; Smart, J.C.

    1979-01-01

    The syntheses of [(C 5 (CH 3 ) 5 ) 2 Mn]PF 6 , (C 5 (CH 3 ) 5 ) 2 Mn, and Na[(C 5 (CH 3 ) 5 ) 2 Mn] are described. Magnetic susceptibility, infrared, electrochemical, NMR, and reactivity studies suggest the formulation of these complexes as low-spin 16-, 17-, and 18-electron planar metallocenes. EPR spectra of the neutral complex are consistent with the 2 E/sub 2g/ configuration determined for other low-spin 17-electron metallocenes. 1 figure, 3 tables

  8. CNN based texture synthesize with Semantic segment

    OpenAIRE

    Liang, Xianye; Zhuo, Bocheng; Li, Peijie; He, Liangju

    2016-01-01

    Deep learning algorithm display powerful ability in Computer Vision area, in recent year, the CNN has been applied to solve problems in the subarea of Image-generating, which has been widely applied in areas such as photo editing, image design, computer animation, real-time rendering for large scale of scenes and for visual effects in movies. However in the texture synthesize procedure. The state-of-art CNN can not capture the spatial location of texture in image, lead to significant distorti...

  9. Financial derivatives

    OpenAIRE

    Koutný, Ondřej

    2012-01-01

    1 Abstract/ Financial derivatives The purpose of this thesis is to provide an introduction to financial derivatives which has been, from the legal perspective, described in a not satisfactory manner as quite little literature that can be found about this topic. The main objectives of this thesis are to define the term "financial derivatives" and its particular types and to analyse legal nature of these financial instruments. The last objective is to try to draft future law regulation of finan...

  10. Financial Derivatives

    DEFF Research Database (Denmark)

    Wigan, Duncan

    2013-01-01

    Contemporary derivatives mark the development of capital and constitute a novel form of ownership. By reconfiguring the temporal, spatial and legal character of ownership derivatives present a substantive challenge to the tax collecting state. While fiscal systems are nationally bounded and inheren......Contemporary derivatives mark the development of capital and constitute a novel form of ownership. By reconfiguring the temporal, spatial and legal character of ownership derivatives present a substantive challenge to the tax collecting state. While fiscal systems are nationally bounded...

  11. Biogenic synthesized nanoparticles and their applications

    International Nuclear Information System (INIS)

    Singh, Abhijeet; Sharma, Madan Mohan

    2016-01-01

    In the present scenario, there are growing concerns over the potential impacts of bioengineered nanoparticles in the health sector. However, our understanding of how bioengineered nanoparticles may affect organisms within natural ecosystems, lags far behind our rapidly increasing ability to engineer novel nanoparticles. To date, research on the biological impacts of bioengineered nanoparticles has primarily consisted of controlled lab studies of model organisms with single species in culture media. Here, we described a cost effective and environment friendly technique for green synthesis of silver nanoparticles. Silver nanoparticles were successfully synthesized from 1 mM AgNO 3 via a green synthesis process using leaf extract as reducing as well as capping agent. Nanoparticles were characterized with the help of UV–vis absorption spectroscopy, X-ray diffraction and TEM analysis which revealed the size of nanoparticles of 30-40 nm size. Further the nanoparticles synthesized by green route are found highly toxic against pathogenic bacteria and plant pathogenic fungi viz. Escherichia coli, Pseudomonas syringae and Sclerotiniasclerotiorum. The most important outcome of this work will be the development of value-added products and protection of human health from pathogens viz., bacteria, virus, fungi etc.

  12. Recent Advances in Chemoenzymatic Peptide Syntheses

    Directory of Open Access Journals (Sweden)

    Kenjiro Yazawa

    2014-09-01

    Full Text Available Chemoenzymatic peptide synthesis is the hydrolase-catalyzed stereoselective formation of peptide bonds. It is a clean and mild procedure, unlike conventional chemical synthesis, which involves complicated and laborious protection-deprotection procedures and harsh reaction conditions. The chemoenzymatic approach has been utilized for several decades because determining the optimal conditions for conventional synthesis is often time-consuming. The synthesis of poly- and oligopeptides comprising various amino acids longer than a dipeptide continues to pose a challenge owing to the lack of knowledge about enzymatic mechanisms and owing to difficulty in optimizing the pH, temperature, and other reaction conditions. These drawbacks limit the applications of the chemoenzymatic approach. Recently, a variety of enzymes and substrates produced using recombinant techniques, substrate mimetics, and optimal reaction conditions (e.g., frozen aqueous media and ionic liquids have broadened the scope of chemoenzymatic peptide syntheses. In this review, we highlight the recent advances in the chemoenzymatic syntheses of various peptides and their use in developing new materials and biomedical applications.

  13. Biogenic synthesized nanoparticles and their applications

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Abhijeet, E-mail: abhijeet.singh@jaipur.manipal.edu; Sharma, Madan Mohan [Manipal University Jaipur (India)

    2016-05-06

    In the present scenario, there are growing concerns over the potential impacts of bioengineered nanoparticles in the health sector. However, our understanding of how bioengineered nanoparticles may affect organisms within natural ecosystems, lags far behind our rapidly increasing ability to engineer novel nanoparticles. To date, research on the biological impacts of bioengineered nanoparticles has primarily consisted of controlled lab studies of model organisms with single species in culture media. Here, we described a cost effective and environment friendly technique for green synthesis of silver nanoparticles. Silver nanoparticles were successfully synthesized from 1 mM AgNO{sub 3} via a green synthesis process using leaf extract as reducing as well as capping agent. Nanoparticles were characterized with the help of UV–vis absorption spectroscopy, X-ray diffraction and TEM analysis which revealed the size of nanoparticles of 30-40 nm size. Further the nanoparticles synthesized by green route are found highly toxic against pathogenic bacteria and plant pathogenic fungi viz. Escherichia coli, Pseudomonas syringae and Sclerotiniasclerotiorum. The most important outcome of this work will be the development of value-added products and protection of human health from pathogens viz., bacteria, virus, fungi etc.

  14. Total Syntheses and Initial Evaluation of [Ψ[C(=S)NH]Tpg4]vancomycin, [Ψ[C(=NH)NH]Tpg4]vancomycin, [Ψ[CH2NH]Tpg4]vancomycin and their (4-Chlorobiphenyl)methyl Derivatives: Synergistic Binding Pocket and Peripheral Modifications for the Glycopeptide Antibiotics

    Science.gov (United States)

    Okano, Akinori; Nakayama, Atsushi; Wu, Kejia; Lindsey, Erick A.; Schammel, Alex W.; Feng, Yiqing; Collins, Karen C.

    2015-01-01

    Full details of studies are disclosed on the total synthesis of binding pocket analogues of vancomycin, bearing the peripheral L-vancosaminyl-1,2-D-glucosyl disaccharide, that contain changes to a key single atom in the residue 4 amide (residue 4 carbonyl O → S, NH, H2) designed to directly address the underlying molecular basis of resistance to vancomycin. Also disclosed are studies piloting the late stage transformations conducted on the synthetically more accessible C-terminus hydroxymethyl aglycon derivatives and full details of the peripheral chlorobiphenyl functionalization of all the binding pocket modified vancomycin analogues designed for dual D-Ala-D-Ala/D-Ala-D-Lac binding are reported. Their collective assessment indicate that combined binding pocket and chlorobiphenyl peripherally modified analogues exhibit a remarkable spectrum of antimicrobial activity (VSSA, MRSA, VanA and VanB VRE) and impressive potencies against both vancomycin-sensitive and vancomycin-resistant bacteria (MICs = 0.06–0.005 μg/mL and 0.5–0.06 μg/mL for the amidine and methylene analogues, respectively) and likely benefit from two independent and synergistic mechanisms of action, only one of which is dependent on D-Ala-D-Ala/D-Ala-D-Lac binding. Such analogues are likely to display especially durable antibiotic activity not prone to rapidly acquired clinical resistance. PMID:25750995

  15. Synthesizing lattice structures in phase space

    International Nuclear Information System (INIS)

    Guo, Lingzhen; Marthaler, Michael

    2016-01-01

    In one dimensional systems, it is possible to create periodic structures in phase space through driving, which is called phase space crystals (Guo et al 2013 Phys. Rev. Lett. 111 205303). This is possible even if for particles trapped in a potential without periodicity. In this paper we discuss ultracold atoms in a driven optical lattice, which is a realization of such a phase space crystals. The corresponding lattice structure in phase space is complex and contains rich physics. A phase space lattice differs fundamentally from a lattice in real space, because its coordinate system, i.e., phase space, has a noncommutative geometry, which naturally provides an artificial gauge (magnetic) field. We study the behavior of the quasienergy band structure and investigate the dissipative dynamics. Synthesizing lattice structures in phase space provides a new platform to simulate the condensed matter phenomena and study the intriguing phenomena of driven systems far away from equilibrium. (paper)

  16. Sorption of mercury on chemically synthesized polyaniline

    International Nuclear Information System (INIS)

    Remya Devi, P.S.; Verma, R.; Sudersanan, M.

    2006-01-01

    Sorption of inorganic mercury (Hg 2+ ) and methyl mercury, on chemically synthesized polyaniline, in 0.1-10N HCl solutions has been studied. Hg 2+ is strongly sorbed at low acidities and the extent of sorption decreases with increase in acidity. The sorption of methyl mercury is very low in the HCl concentration range studied. Sorption of Hg 2+ on polyaniline in 0.1-10N LiCl and H 2 SO 4 solutions has also been studied. The analysis of the data indicates that the sorption of Hg 2+ depends on the degree of protonation of polyaniline and the nature of mercury(II) chloride complexes in solution. X-ray photoelectron spectroscopy analysis (XPS) of polyaniline sorbed with mercury show that mercury is bound as Hg 2+ . Sorbed mercury is quantitatively eluted from polyaniline with 0.5N HNO 3 . Polyaniline can be used for separation and pre-concentration of inorganic mercury from aqueous samples. (author)

  17. Hydrothermal syntheses and crystal structure of NH

    International Nuclear Information System (INIS)

    Kang, Z. J.; Wang, Y. X.; You, F. T.; Lin, J. H.

    2001-01-01

    Ammonium rare earth fluorides NH(sub 4)Ln(sub 3)F(sub 10) (Ln=Dy, Ho, Y, Er, Tm) were synthesized by a hydrothermal method. Two polymorphs, of the hexagonal(beta)-KYb(sub 3)F(sub 10) and the cubic(gamma)-KYb(sub 3)F(sub 10) structure types, were formed under hydrothermal conditions for most of the rare earth fluorides except NH(sub 4)Dy(sub 3)F(sub 10), for which only the cubic -phase was obtained. The crystal structures of MLn(sub 3)F(sub 10) (M=alkaline metal, NH(sup+4) and Ln=rare earth) show a strong correlation to the ratio of ionic radii (R(sub M)/R(sub Ln)), which has been expressed in a structure phase diagram of the ionic radii of univalent and rare earth cations

  18. Methods for synthesizing metal oxide nanowires

    Science.gov (United States)

    Sunkara, Mahendra Kumar; Kumar, Vivekanand; Kim, Jeong H.; Clark, Ezra Lee

    2016-08-09

    A method of synthesizing a metal oxide nanowire includes the steps of: combining an amount of a transition metal or a transition metal oxide with an amount of an alkali metal compound to produce a mixture; activating a plasma discharge reactor to create a plasma discharge; exposing the mixture to the plasma discharge for a first predetermined time period such that transition metal oxide nanowires are formed; contacting the transition metal oxide nanowires with an acid solution such that an alkali metal ion is exchanged for a hydrogen ion on each of the transition metal oxide nanowires; and exposing the transition metal oxide nanowires to the plasma discharge for a second predetermined time period to thermally anneal the transition metal oxide nanowires. Transition metal oxide nanowires produced using the synthesis methods described herein are also provided.

  19. Structure of the enzymatically synthesized fructan inulin

    Energy Technology Data Exchange (ETDEWEB)

    Heyer, A.G.; Schroeer, B. [Max-Planck-Institut fuer Molekulare Pflanzenphysiologie, Karl-Liebknecht-Str. 25, 14476 Golm (Germany); Radosta, S. [Fraunhofer-Institut fuer Angewandte Polymerforschung, Postfach 126, 14504 Teltow (Germany); Wolff, D.; Czapla, S.; Springer, J. [Technische Universitaet Berlin, FG Makromolekulare Chemie, Str. des 17. Juni 135, 10623 Berlin (Germany)

    1998-12-15

    Construction, purification and characterization of a fusion protein of maltose-binding protein of Escherichia coli and the fructosyltransferase of Streptococcus mutans is described. With the purified protein, in vitro synthesis of inulin was performed. The obtained polysaccharide was characterized by high-performance size-exclusion chromatography (HPSEC) and static light scattering (SLS) in dilute aqueous and dimethyl sulfoxide solution. For all samples very high molecular weights between 60x10{sup 6} and 90x10{sup 6} g/mol and a remarkable small polydispersity index of 1.1 have been determined. Small root-mean-square radii of gyration point to a compact conformation in dilute solution. No difference between native and enzymatically synthesized inulin was observed by X-ray powder diffraction and thermoanalysis of solid samples. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  20. Structure of the enzymatically synthesized fructan inulin

    International Nuclear Information System (INIS)

    Heyer, A.G.; Schroeer, B.; Radosta, S.; Wolff, D.; Czapla, S.; Springer, J.

    1998-01-01

    Construction, purification and characterization of a fusion protein of maltose-binding protein of Escherichia coli and the fructosyltransferase of Streptococcus mutans is described. With the purified protein, in vitro synthesis of inulin was performed. The obtained polysaccharide was characterized by high-performance size-exclusion chromatography (HPSEC) and static light scattering (SLS) in dilute aqueous and dimethyl sulfoxide solution. For all samples very high molecular weights between 60x10 6 and 90x10 6 g/mol and a remarkable small polydispersity index of 1.1 have been determined. Small root-mean-square radii of gyration point to a compact conformation in dilute solution. No difference between native and enzymatically synthesized inulin was observed by X-ray powder diffraction and thermoanalysis of solid samples. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  1. Enhanced Electromagnetic and Chemical/Biological Sensing. Properties of Atomic Cluster-Derived Materials

    National Research Council Canada - National Science Library

    Schatz, George

    2003-01-01

    The Center for Atomic Clusters-derived Materials performed a broad range of research concerned with synthesizing, characterizing and utilizing atomic and molecular clusters, nanoparticles and nanomaterial...

  2. 5-Nitroimidazole Derivatives and their Antimicrobial Activity

    International Nuclear Information System (INIS)

    Khan, K.M.; Salar, U.; Yousuf, S.; Naz, F.

    2016-01-01

    5-Nitroimidazole derivatives 2-8 were synthesized from secnidazole. The syntheses were accomplished in two steps which start from the oxidation of secnidazole to the secnidazolone 1. Secnidazolone 1 was converted into its hydrazone derivative 2-8 by treating with different substituted acid hydrazide. Compounds 2-8 were evaluated for their antimicrobial activity against Gram-positive and Gram-negative bacteria, compounds 3 and 4 showed the significant activity against Staphylococcus epidermidis, however, compound 2 showed good inhibitions against Corynebacterium diphtheria when compared with the standard. Compound 3 showed good inhibitory potential against tested Gram-negative bacterial strains i.e. Enterobacter aerogene, Escherichia coli, Salmonella typhi, Salmonella paratyphi A, Shigella flexeneri and Vibrio choleriae. All synthetic derivatives were also tested against eight fungal stains, however, they were weekly active against Aspergillus flavus and Candida albican. The synthesized compounds were characterized by different spectroscopy techniques. (author)

  3. National Gas Survey. Synthesized gaseous hydrocarbon fuels

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-06-01

    The supply-Technical Advisory Task Force-Synthesized Gaseous Hydrocarbon Fuels considered coal, hydrocarbon liquids, oil shales, tar sands, and bioconvertible materials as potential feedstocks for gaseous fuels. Current status of process technology for each feedstock was reviewed, economic evaluations including sensitivity analysis were made, and constraints for establishment of a synthesized gaseous hydrocarbon fuels industry considered. Process technology is presently available to manufacture gaseous hydrocarbon fuels from each of the feedstocks. In 1975 there were eleven liquid feedstock SNG plants in the United States having a capacity of 1.1 billion SCFD. There can be no contribution of SNG before 1982 from plants using feedstocks other than liquids because there are no plants in operation or under construction as of 1977. Costs for SNG are higher than current regulated prices for U.S. natural gas. Because of large reserves, coal is a prime feedstock candidate although there are major constraints in the area of coal leases, mining and water permits, and others. Commercial technology is available and several new gasification processes are under development. Oil shale is also a feedstock in large supply and commercial process technology is available. There are siting and permit constraints, and water availability may limit the ultimate size of an oil shale processing industry. Under projected conditions, bioconvertible materials are not expected to support the production of large quantities of pipeline quality gas during the next decade. Production of low or medium Btu gas from municipal solid wastes can be expected to be developed in urban areas in conjunction with savings in disposal costs. In the economic evaluations presented, the most significant factor for liquid feedstock plants is the anticipated cost of feedstock and fuel. The economic viability of plants using other feedstocks is primarily dependent upon capital requirements.

  4. Porous oxides synthesized by the combustion method

    International Nuclear Information System (INIS)

    Lugo L, V.

    2005-01-01

    The result of this work, seeks to be a contribution for the treatment of radioactive wastes, with base to the sorption properties that present those porous oxides, synthesized by a method that allows to increase the sorption capacity. The main objective of the present investigation has been the modification of the structural characteristics of the oxides of Fe, Mg and Zn to increase its capacity of sorption of 60 Co in particular. It was studied the effect of the synthesis method by combustion in the inorganic oxides; the obtained solids were characterized using the following techniques: X-ray diffraction (XRD), scanning electron microscopy (SEM), semiquantitative elementary analysis by Dispersive energy spectroscopy (EDS) and determination of surface area by the Brunauner-Emmett-Teller method (BET). Also was carried out batch type experiments for the sorption of Co 2+ , with the purpose of studying the sorption capacity of each one of the prepared oxides. In accordance with that previously exposed, the working plan that was carried out in this investigation is summarized in the following stages: 1. Preparation of inorganic oxides by two different methods, studying the effect of the temperature in the synthesis process. 2. Characterization of the inorganic oxides by XRD, by means of which those were chosen the solids with better properties. 3. Characterization of the inorganic oxides by SEM and EDS where it was studied the morphology of the synthesized materials and the semiquantitative elemental composition. 4. Realization of a sorption experiment type Batch with non radioactive Co 2+ to simulate the sorption of 60 Co and determination of the sorption capacity by means of neutron activation of the non radioactive cobalt. 5. Determination of the surface area by the (BET) technique of the inorganic oxides with better sorption properties. (Author)

  5. Synthesizing Earth's geochemical data for hydrogeochemical analysis

    Science.gov (United States)

    Brantley, S. L.; Kubicki, J.; Miller, D.; Richter, D.; Giles, L.; Mitra, P.

    2007-12-01

    For over 200 years, geochemical, microbiological, and chemical data have been collected to describe the evolution of the surface earth. Many of these measurements are data showing variations in time or in space. To forward predict hydrologic response to changing tectonic, climatic, or anthropogenic forcings requires synthesis of these data and utilization in hydrogeochemical models. Increasingly, scientists are attempting to synthesize such data in order to make predictions for new regions or for future time periods. However, to make such complex geochemical data accessible requires development of sophisticated cyberinfrastructures that both invite uploading as well as usage of data. Two such cyberinfrastructure (CI) initiatives are currently developing, one to invite and promote the use of environmental kinetics data (laboratory time course data) through ChemxSeer, and the other to invite and promote the use of spatially indexed geochemical data for the Earth's Critical Zone through CZEN.org. The vision of these CI initiatives is to provide cyber-enhanced portals that encourage domain scientists to upload their data before publication (in private cyberspace), and to make these data eventually publicly accessible (after an embargo period). If the CI can be made to provide services to the domain specialist - e.g. to provide data analysis services or data comparison services - we envision that scientists will upload data. In addition, the CI can promote the use and comparison of datasets across disciplines. For example, the CI can facilitate the use of spatially indexed geochemical data by scientists more accustomed to dealing with time-course data for hydrologic flow, and can provide user-friendly interfaces with CI established to facilitate the use of hydrologic data. Examples of the usage of synthesized data to predict soil development over the last 13ky and its effects on active hydrological flow boundaries in surficial systems will be discussed for i) a N

  6. Analytical model and behavioral simulation approach for a ΣΔ fractional-N synthesizer employing a sample-hold element

    DEFF Research Database (Denmark)

    Cassia, Marco; Shah, Peter Jivan; Bruun, Erik

    2003-01-01

    A previously unknown intrinsic nonlinearity of standard SigmaDelta fractional-N synthesizers is identified. A general analytical model for SigmaDelta fractional-N phased-locked loops (PLLs) that includes the effect of the nonlinearity is derived and an improvement to the synthesizer topology is d...

  7. Effect of zinc oxide nanoparticles synthesized by a precipitation ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 38; Issue 4. Effect of zinc oxide nanoparticles synthesized by a ... ZnO nanoparticles were synthesized by a precipitation method in aqueous media from zinc nitrate hexahydrate and sodium hydroxide. The synthesized ZnO nanoparticles exhibited a crystalline structure ...

  8. Effect of zinc oxide nanoparticles synthesized by a precipitation ...

    Indian Academy of Sciences (India)

    ZnO nanoparticles were synthesized by a precipitation method in aqueous media from zinc nitrate hexahydrate and sodium hydroxide. The synthesized ZnO nanoparticles exhibited a crystalline structure with hexagonal structure of the wurtzite. The morphology of the synthesized ZnO nanoparticles presented a spherical ...

  9. Simple tertiary phosphines to hexaphosphane ligands: Syntheses ...

    Indian Academy of Sciences (India)

    The half-sandwich ruthenium complexes were employed in the cyclopropanation reaction of styrene derivatives in the presence of diphenyldiazomethane. Interestingly, all complexes afforded 1,1,3,3-tetra- phenyl cyclobutane along with cyclopropane deriva- tives with [CpRu(PPh2N(nBu)PPh2)(PPh3)]Cl (22) showing better ...

  10. Syntheses and structural characterization of new dithiophosphinato ...

    Indian Academy of Sciences (India)

    L4) and 2-propyl, (L5). To the best of our knowledge, this is the first report on the preparation and characterization of the n-butyl- derivative. The acid forms of the ligands were obtained by treatment of the Lawesson reagent, (LR) [2,4-bis(4-.

  11. Global Derivatives

    DEFF Research Database (Denmark)

    Andersen, Torben Juul

    ." - Steen Parsholt, Chairman and CEO, Aon Nordic Region. "Andersen has done a wonderful job of developing a comprehensive text that deals with risk management in global markets. I would recommend this book to any student or businessman who has a need to better understand the risks and risk management......""In Global Derivatives: A Strategic Risk Management Perspective", Torben Juul Andersen has succeeded to gather in one book a complete and thorough summary and an easy-to-read explanation of all types of derivative instruments and their background, and their use in modern management of risk...... approaches to dealing in the global business environment." - Sharon Brown-Hruska, Commissioner, Commodity Futures Trading Commission, USA. "This comprehensive survey of modern risk management using derivative securities is a fine demonstration of the practical relevance of modern derivatives theory to risk...

  12. Therapeutic Versatility of Resveratrol Derivatives.

    Science.gov (United States)

    Nawaz, Waqas; Zhou, Zhongqin; Deng, Sa; Ma, Xiaodong; Ma, Xiaochi; Li, Chuangang; Shu, Xiaohong

    2017-10-29

    Resveratrol, a natural phytoalexin, exhibits a remarkable range of biological activities, such as anticancer, cardioprotective, neuroprotective and antioxidant properties. However, the therapeutic application of resveratrol was encumbered for its low bioavailability. Therefore, many researchers focused on designing and synthesizing the derivatives of resveratrol to enhance the bioavailability and the pharmacological activity of resveratrol. During the past decades, a large number of natural and synthetic resveratrol derivatives were extensively studied, and the methoxylated, hydroxylated and halogenated derivatives of resveratrol received particular more attention for their beneficial bioactivity. So, in this review, we will summarize the chemical structure and the therapeutic versatility of resveratrol derivatives, and thus provide the related structure activity relationship reference for their practical applications.

  13. Sulfonamide Derivatives of 2-Amino-1-phenylethane as Suitable ...

    African Journals Online (AJOL)

    Methods: A series of sulfamoyl derivatives, 3a-l, of 1-amino-2-phenylethane (1) were synthesized by reacting with various aryl sulfonyl chlorides, 2a-l, in the presence of aqueous Na2CO3 solution under definite pH control. All the synthesized molecules were screened against three enzymes, acetyl cholinesterase (AChE), ...

  14. Synthesis and Antifungal Activities of Some Novel Pyrimidine Derivatives

    Directory of Open Access Journals (Sweden)

    Dequn Sun

    2011-06-01

    Full Text Available Three series of new pyrimidine derivatives were synthesized and their antifungal activities were evaluated in vitro against fourteen phytopathogenic fungi. The results indicated that most of the synthesized compounds possessed fungicidal activities and some of them are more potent than the control fungicides. Preliminary SAR was also discussed.

  15. Multifunctional Cinnamic Acid Derivatives

    Directory of Open Access Journals (Sweden)

    Aikaterini Peperidou

    2017-07-01

    Full Text Available Our research to discover potential new multitarget agents led to the synthesis of 10 novel derivatives of cinnamic acids and propranolol, atenolol, 1-adamantanol, naphth-1-ol, and (benzylamino ethan-1-ol. The synthesized molecules were evaluated as trypsin, lipoxygenase and lipid peroxidation inhibitors and for their cytotoxicity. Compound 2b derived from phenoxyphenyl cinnamic acid and propranolol showed the highest lipoxygenase (LOX inhibition (IC50 = 6 μΜ and antiproteolytic activity (IC50 = 0.425 μΜ. The conjugate 1a of simple cinnamic acid with propranolol showed the higher antiproteolytic activity (IC50 = 0.315 μΜ and good LOX inhibitory activity (IC50 = 66 μΜ. Compounds 3a and 3b, derived from methoxylated caffeic acid present a promising combination of in vitro inhibitory and antioxidative activities. The S isomer of 2b also presented an interesting multitarget biological profile in vitro. Molecular docking studies point to the fact that the theoretical results for LOX-inhibitor binding are identical to those from preliminary in vitro study.

  16. Quinonaphthothiazines, syntheses, structures and anticancer activities

    Science.gov (United States)

    Jeleń, M.; Pluta, K.; Suwińska, K.; Morak-Młodawska, B.; Latocha, M.; Shkurenko, A.

    2015-11-01

    Two new types of pentacyclic azaphenothiazines being quinonaphthothiazines were obtaining from the reactions of dichlorodiquinolinyl disulfide with 1- and 2-naphthylamines. As the reactions could proceed in many ways, the proper structure elucidation was crucial. The structure determination was based on the 2D NMR spectra (NOESY, HSQC and HMBC) of the methyl derivatives. The final structure evidences came from X-ray analysis of the monocrystals. The new quinonaphthothiazines represent angularly fused pentacyclic ring systems which is folded along the N-S axis. The parent NH-compounds were transformed into the N-derivatives. Some quinonaphthothiazines exhibited promising anticancer activity against glioblastoma SNB-19, melanoma C-32 and human ductal breast epithelial tumor T47D cell lines. The anticancer activity dependent on the nature of the substituents and the ring fusion between the thiazine and naphthalene moieties. Two compounds were more active than the reference drug, cisplatin.

  17. [Femicides in ethnic and racialized groups: syntheses].

    Science.gov (United States)

    Meneghel, Stela Nazareth; Lerma, Betty Ruth Lozano

    2017-01-01

    The text entitled "Femicides in ethnic and racialized groups: syntheses" presents some of the discussions that took place during a seminar on this topic in Buenaventura. Buenaventura is the main Colombian port on the Pacific, a region rich in minerals and a corridor for the movement of goods, which makes it a strategic territory and a center for disputes. At the seminar, the social and political determinants of femicide were discussed, understanding it as a tactic of waging war against women. The forum provided a space for academic discussion, but also for grievances over inter-personal violence, the manifestation of feelings and the elaboration of pain and grief through the medium of art. We believe that the dissemination of this experience to the Brazilian public, in a country with ethnic, social and racial vulnerability similar to that in Colombia, will be of value to social and health workers. The scope of this paper is therefore to provide the opinion of its authors on the determinants of femicides and on actions to tackle them, in addition to a synthesis of the discussions and debates that permeated the event.

  18. Feedback Synthesizes Neural Codes for Motion.

    Science.gov (United States)

    Clarke, Stephen E; Maler, Leonard

    2017-05-08

    In senses as diverse as vision, hearing, touch, and the electrosense, sensory neurons receive bottom-up input from the environment, as well as top-down input from feedback loops involving higher brain regions [1-4]. Through connectivity with local inhibitory interneurons, these feedback loops can exert both positive and negative control over fundamental aspects of neural coding, including bursting [5, 6] and synchronous population activity [7, 8]. Here we show that a prominent midbrain feedback loop synthesizes a neural code for motion reversal in the hindbrain electrosensory ON- and OFF-type pyramidal cells. This top-down mechanism generates an accurate bidirectional encoding of object position, despite the inability of the electrosensory afferents to generate a consistent bottom-up representation [9, 10]. The net positive activity of this midbrain feedback is additionally regulated through a hindbrain feedback loop, which reduces stimulus-induced bursting and also dampens the ON and OFF cell responses to interfering sensory input [11]. We demonstrate that synthesis of motion representations and cancellation of distracting signals are mediated simultaneously by feedback, satisfying an accepted definition of spatial attention [12]. The balance of excitatory and inhibitory feedback establishes a "focal" distance for optimized neural coding, whose connection to a classic motion-tracking behavior provides new insight into the computational roles of feedback and active dendrites in spatial localization [13, 14]. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Synthetic Approaches and Biological Activities of 4-Hydroxycoumarin Derivatives

    Directory of Open Access Journals (Sweden)

    Oee-Sook Park

    2009-11-01

    Full Text Available The main purpose of this review is to summarize recent chemical syntheses and structural modifications of 4-hydroxycoumarin and its derivatives, of interest due to their characteristic conjugated molecular architecture and biological activities.

  20. Epibatidine-derivatives: ligands for the neuronal nicotinic acetylcholine receptor

    International Nuclear Information System (INIS)

    Westera, G.; Patt, J.T.; Jankowski, K.; Bertrand, D.; Spang, J.; Schubiger, P.A.

    1997-01-01

    Epibatidine, isolated from the Ecuadorian frog Epipedobates tricolar, has been synthesized. 11 C-N-methyl derivate is investigated as useful nicotinergic receptor ligand by electrophysiological methods and in vivo mice experiments. (author) 2 figs., 7 refs

  1. Derivative chameleons

    International Nuclear Information System (INIS)

    Noller, Johannes

    2012-01-01

    We consider generalized chameleon models where the conformal coupling between matter and gravitational geometries is not only a function of the chameleon field φ, but also of its derivatives via higher order co-ordinate invariants (such as ∂ μ φ∂ μ φ,□φ,...). Specifically we consider the first such non-trivial conformal factor A(φ,∂ μ φ∂ μ φ). The associated phenomenology is investigated and we show that such theories have a new generic mass-altering mechanism, potentially assisting the generation of a sufficiently large chameleon mass in dense environments. The most general effective potential is derived for such derivative chameleon setups and explicit examples are given. Interestingly this points us to the existence of a purely derivative chameleon protected by a shift symmetry for φ → φ+c. We also discuss potential ghost-like instabilities associated with mass-lifting mechanisms and find another, mass-lowering and instability-free, branch of solutions. This suggests that, barring fine-tuning, stable derivative models are in fact typically anti-chameleons that suppress the field's mass in dense environments. Furthermore we investigate modifications to the thin-shell regime and prove a no-go theorem for chameleon effects in non-conformal geometries of the disformal type

  2. Some Heteroaromatic Organomercurials, Their Syntheses and Reactions: A Review of Our Research (1980-2000

    Directory of Open Access Journals (Sweden)

    Piotr Wroczynski

    2001-11-01

    Full Text Available This review reports some novel (or improved synthetic methods for preparing a number of aromatic (carbocyclic and predominantly heterocyclic organomercurials, particularly those derived from theophylline, theobromine and uracil, as well as some novel halo- and cyano-demercuration reactions. We have also synthesized the first stable organic derivative of mercury(I, viz. 1,8-bis(acetoxydimercurio theobromine, and studied its novel reactions. We have also improved the old Willgerodt method (1897, applicable for preparing various diaryliodonium chlorides from appropriate (dichloroiodoarenes and symmetric aromatic mercurials. A full list of our works, published over the past twenty years (1980-2000, is also provided (see Refs. 1-16.

  3. Domino syntheses of bioactive tetronic and tetramic acids

    Science.gov (United States)

    Schobert, Rainer

    2007-01-01

    Natural products containing tetronic acid or tetramic acid moieties continue to attract the interest of chemists, biologists, and physicians due to their challenging structures and to the wide range of biological activities they display. This review portrays the structural varieties of tetronic and tetramic acids and the spectrum of possible therapeutically relevant effects in man for exemplary derivatives. Their biosynthetic origin from α-amino and α-hydroxy acids is briefly discussed as is the relationship between their structures and their modes of interaction with biochemical effectors such as metal cations or enzymes. A short overview of laboratory syntheses of the heterocyclic core structures of tetramic and tetronic acids is provided with an emphasis on those emulating the biosynthesis. A synthesis from the α-amino or α-hydroxy esters and the cumulated phosphorus ylide Ph3PCCO based upon a domino addition-intra-Wittig alkenation sequence is presented with applications to the preparation of the antibiotics reutericyclin and tenuazonic acid, the cytotoxic melophlin B, and the enzyme inhibitor RK-682. Procedural advantages of immobilizing either starting component by attaching it to a resin and its exploitation in the parallel synthesis of libraries of potential drug candidates are described. The basic domino reaction can even be extended by further C-C bond forming steps when starting from suitable α-hydroxy or α-amino allyl esters. Depending on the chosen reaction conditions, bioactive intermediates of formally three to seven step long cascades can be obtained. Among them, herbicidal 3-alkyltetronic acids and lactone endoperoxides with antiplasmodial activity exceeding that of the natural antimalarial lead artemisinin. Hence, this domino reaction gives access to diversely functionalized derivatives of tetronic and tetramic acids. As it can also be ported to solid phase, it is ideally suited for parallel and combinatorial processing. Future developments

  4. Global Derivatives

    DEFF Research Database (Denmark)

    Andersen, Torben Juul

    , postgraduate qualification or MBA programme. This book also caters for practicing managers and executives who need to understand current developments in global derivatives markets and require cutting-edge insight on strategic risk management issues. Dr Torben Juul Andersen is currently Associate Professor...... approaches to dealing in the global business environment." - Sharon Brown-Hruska, Commissioner, Commodity Futures Trading Commission, USA. "This comprehensive survey of modern risk management using derivative securities is a fine demonstration of the practical relevance of modern derivatives theory to risk...... management practice. Of particular note is the global and integrated approach chosen in this book which should be of special interest to aspiring managers active in global and international markets." - Dr Jean-Pierre Zigrand, Lecturer in Finance, London School of Economics, UK. More than 90 per cent...

  5. Electricity derivatives

    CERN Document Server

    Aïd, René

    2015-01-01

    Offering a concise but complete survey of the common features of the microstructure of electricity markets, this book describes the state of the art in the different proposed electricity price models for pricing derivatives and in the numerical methods used to price and hedge the most prominent derivatives in electricity markets, namely power plants and swings. The mathematical content of the book has intentionally been made light in order to concentrate on the main subject matter, avoiding fastidious computations. Wherever possible, the models are illustrated by diagrams. The book should allow prospective researchers in the field of electricity derivatives to focus on the actual difficulties associated with the subject. It should also offer a brief but exhaustive overview of the latest techniques used by financial engineers in energy utilities and energy trading desks.

  6. Conducting polymer networks synthesized by photopolymerization-induced phase separation

    Science.gov (United States)

    Yamashita, Yuki; Komori, Kana; Murata, Tasuku; Nakanishi, Hideyuki; Norisuye, Tomohisa; Yamao, Takeshi; Tran-Cong-Miyata, Qui

    2018-03-01

    Polymer mixtures composed of double networks of a polystyrene derivative (PSAF) and poly(methyl methacrylate) (PMMA) were alternatively synthesized by using ultraviolet (UV) and visible (Vis) light. The PSAF networks were generated by UV irradiation to photodimerize the anthracene (A) moieties labeled on the PSAF chains, whereas PMMA networks were produced by photopolymerization of methyl methacrylate (MMA) monomer and the cross-link reaction using ethylene glycol dimethacrylate (EGDMA) under Vis light irradiation. It was found that phase separation process of these networks can be independently induced and promptly controlled by using UV and Vis light. The characteristic length scale distribution of the resulting co-continuous morphology can be well regulated by the UV and Vis light intensity. In order to confirm and utilize the connectivity of the bicontinuous morphology observed by confocal microscopy, a very small amount, 0.1 wt%, of multi-walled carbon nanotubes (MWCNTs) was introduced into the mixture and the current–voltage (I–V) relationship was subsequently examined. Preliminary data show that MWCNTs are preferentially dispersed in the PSAF-rich continuous domains and the whole mixture became electrically conducting, confirming the connectivity of the observed bi-continuous morphology. The experimental data obtained in this study reveal a promising method to design various scaffolds for conducting soft matter taking advantages of photopolymerization-induced phase separation.

  7. Evaluation and application of surfactants synthesized from asphalt components

    Directory of Open Access Journals (Sweden)

    E.R. Souaya

    2012-06-01

    Full Text Available The synthesis, characterization, surface activity and applications of nonionic surfactants derived from the asphalt components (maltenes M are presented. These compounds were synthesized by the sulfonation of (maltene, then the prepared maltene sulfonic acid (MS was reacted with hexadecylamine giving maltene sulfonamide product (A which undergoes an alkali-catalyzed ethoxylation at (135–150 °C. Several surfactants (M-10 to M-40 were formed with different ethylene oxide units (from 10 up to 40 and were characterized by molecular weight determinations, elemental analyses and FTIR analysis. Surface tension, as a function of concentration of the surfactants in the aqueous media, was measured at 25 °C. From these measurements, the critical micelle concentration (CMC, the maximum surface excess concentration (Гmax, Minimum area per molecule (Amin, effectiveness of surface reduction (ПCMC and the efficiency (pC20 were calculated. The prepared surfactants were applied as emulsifying agents for making asphalt emulsions. Storage stability, (Saybolt Furol viscosity, settlement (water content difference %, coating ability and water resistance were measured. The results indicated that M-20 (maltene sulfonamide ethoxylated with 20 units of ethylene oxides gives a maximum stability.

  8. An efficient conversion of maleimide derivatives to 2-thioxo imidazolidinones.

    OpenAIRE

    Lydia Salhi; Samia Bouzroura-Aichouche; Yamina Benmalek; Yamina Bentarzi; Sophie Poulain-Martini; Bastien Cacciuttolo; Elisabet Dunach; Bellara Nedjar-Kolli

    2013-01-01

    Starting from maleimide derivatives, a series of 2-thioxoimidazolidinones was prepared through two different procedures. These syntheses have achieved in two steps via reaction between maleimide derivatives 1,semicarbazide hydrochloride 9 and isothiocyanates5,the best results being obtained under acid conditions (AcOH or heteropolyacid in ethanol or acétonitrile). The synthesized compounds 11a-f and substituted thiohydantoins 6a-h, 8a-h were screened for their in vitro anti-bacterial activity...

  9. Synthesis and Antimicrobial Activity of Amino Acids Conjugated Diphenylmethylpiperazine Derivatives

    Directory of Open Access Journals (Sweden)

    K. N. Shivakumara

    2009-01-01

    Full Text Available A series of amino acid conjugated diphenylmethylpiperazine derivatives were synthesized by coupling diphenylmethylpiperazine with different Boc-amino acids using EDCI/HOBt as coupling agent and NMM as base. The synthesized compounds were characterized by 1H-NMR and elemental analysis. The Boc-deblocked derivatives were tested for their antimicrobial activity. We are here reporting that Phe and Trp conjugated diphenylmethylpiperazine showed equally good antibacterial activities as that of conventional antimicrobial drugs.

  10. Study of photoconductor polymers synthesized by plasma

    International Nuclear Information System (INIS)

    Enriquez P, M.A.

    2007-01-01

    In this work the photoconductivity in poly thiophene (PTh), poly pyrrole (PPy) and doped poly pyrrole with iodine (PPy/I) is studied, whose structures depend of the intensity of the electric field applied during the synthesis by plasma. The conjugated organic polymers possess double alternated bonds in its chemical structure that its allow the one movement of π electrons through the polymeric chains. The plasma is produced by means of splendor discharges to 13.5 MHz, resistive coupling, at one pressure that oscillates in the interval from 2 to 3x10 -1 mbar, 180 min and powers of 10, 24, 40, 60 , 80 and 100 W. Its were used heteroaromatic polymers like PTh and PPy/I, due to their potential applications in optoelectronics. The influence of the iodine is evaluated as dopant in PPy and it is compared with their similar one without doping in the light absorption/emission processes. The polymers synthesized by plasma can ramify or to intersect due to the energy applied during the synthesis. However, if the polymer intersects, the aromaticity can continue through the polymeric chains. The absorptions obtained by infrared spectroscopy, suggest that the polymer conserves the aromatic structure of the monomer fundamentally with substitutions that indicate inter crossing and partial fragmentation. The structure of most of the polymers spreads to be amorphous because they don't possess any classification. However, the PPy/I and PTh synthesized by this technique present crystalline segments whose intensity diminishes with the power of the discharge. In PTh, the average crystallinity diminishes from 19.8% to 9.9%, and in PPy/I of 15.9% to 13.3% in the interval of 10 to 100 W of power. In this work, however, its were crystalline arrangements in all the studied powers. The classification of the polymeric structure favors the formation of trajectories of transfer of electric loads among the chains, that which influences in the global electric conductivity of the material. In UV

  11. Syntheses of Gliocladin C and Related Alkaloids.

    Science.gov (United States)

    Hodges, Timothy R; Benjamin, Noah M; Martin, Stephen F

    2017-05-05

    A unique approach to gliocladin C and related alkaloids was developed that features an unprecedented nucleophilic addition of a diketopiperazine to an isatin derivative followed by a Friedel-Crafts alkylation of the resultant tertiary alcohol with indole to set the key quaternary center. Chemoselective oxindole reduction and cyclization delivered a pivotal hexahydropyrrolo[2,3-b]indole diketopiperazine intermediate that was readily converted into (±)-gliocladin C, (±)-T988C, and (±)-gliocladine C, culminating in the shortest approach to these alkaloids reported to date.

  12. Development of a novel synthetic method for ring construction using organometallic complexes and its application to the total syntheses of natural products.

    Science.gov (United States)

    Mori, Miwako

    2005-05-01

    Organometallic complexes are useful tools in synthetic organic chemistry. We investigated a novel synthetic method for ring construction using organometallic complexes and synthesized natural products and biologically active substances using these methods. Metalacycles formed from an early transition metal and diene, enyne, and diyne are stable under the reaction conditions and they are easily converted into compounds with functional groups by the addition of various agents. We have developed a novel synthetic method of heterocycles from enyne and diene using Cp2ZrBu2. The total syntheses of (-)-dendrobine, (+/-)-mecembrane, and (+/-)-mecembrine were achieved using this procedure. To synthesize these natural products as a chiral form, a novel palladium-catalyzed asymmetric allylic amination was developed, and chiral 2-arylcyclohexenylamine derivatives were synthesized. From these compounds, the total syntheses of (-)-mesembrane, (-)-mesembrine, (+)-crinamine, (-)-haemanthidine, and (+)-pretazetine were achieved. By further development of this procedure, a chiral 2-siloxymethylcyclohexenylamine derivative could be synthesized and the novel synthesis of indole derivatives was developed from this compound. From this indole derivative, (-)-tsubifoline and (-)-strychnine were synthesized.

  13. Electricity derivatives

    OpenAIRE

    Barone-Adesi, Giovanni; Gigli, Andrea

    2006-01-01

    In this paper we propose an algorithm for pricing derivatives written on electricity in an incomplete market setting. A discrete time model for price dynamics which embodies the main features of electricity price revealed by simple time series analysis is considered. We use jointly Binomial and Monte Carlo methods for pricing under a risk-neutral measure of which we prove the existence.

  14. dione derivatives

    Indian Academy of Sciences (India)

    dione derivatives via de-Boc and cyclization reaction in modest yield. Spectroscopic (1H, 13C NMR, and Mass) and analytical techniques have been used to identify and confirm the structure of the products. Keywords. Triflic anhydride; Boc anhydride; Negishi coupling; acid-amine coupling; cyclization reaction; cytotoxicity ...

  15. Neurofilament proteins are synthesized in nerve endings from squid brain.

    Science.gov (United States)

    Crispino, M; Capano, C P; Kaplan, B B; Giuditta, A

    1993-09-01

    It is generally believed that the proteins of the nerve endings are synthesized on perikaryal polysomes and are eventually delivered to the presynaptic domain by axoplasmic flow. At variance with this view, we have reported previously that a synaptosomal fraction from squid brain actively synthesizes proteins whose electrophoretic profile differs substantially from that of the proteins made in nerve cell bodies, axons, or glial cells, i.e., by the possible contaminants of the synaptosomal fraction. Using western analyses and immunoabsorption methods, we report now that (a) the translation products of the squid synaptosomal fraction include neurofilament (NF) proteins and (b) the electrophoretic pattern of the synaptosomal newly synthesized NF proteins is drastically different from that of the NF proteins synthesized by nerve cell bodies. The latter results exclude the possibility that NF proteins synthesized by the synaptosomal fraction originate in fragments of nerve cell bodies possibly contaminating the synaptosomal fraction. They rather indicate that in squid brain, nerve terminals synthesize NF proteins.

  16. [Synthesis of 1,3-dihydro-1,3-dioxo-2H-isoindole derivatives].

    Science.gov (United States)

    Yang, Yue; Xiang, Dong; Guo, Ju; Zheng, Yong-sheng; Ye, Bin; Yang, Jin-liang; Cheng, Li

    2008-07-01

    To synthesize a series of derivatives of Thalidomide. The N-Phthaloyl-L-glutamic anhydride was ammonolyzed with amino acid benzyl esters, followed by hydrogenization. The reaction between the hydogenized products and ammonia gas produced ammonium salt, 1,3-dihydro-1,3-dioxo-2H-isoindole derivatives. Four new derivatives of Thalidomide were obtained and confirmed by spectral detection. The derivatives of Thalidomide can be efficiently synthesized under mild conditions.

  17. SYNTHESE DE DERIVES DE BENZOQUINOLEINE A PARTIR DE NAPHTAMIDES PAR LA METHODE DE VILSMEIR

    Directory of Open Access Journals (Sweden)

    A BENBOUDIAF

    2003-12-01

    Full Text Available Ce travail porte sur une extension des voies de synthèse de dérivés de benzoquinoléines à partir de naphtamides en utilisant le réactif de Vilsmeir dissout dans l'oxychlorure de phosphore. L’exploitation pratique de cette méthode, développée auparavant  par Otto Meth-Cohn et Davidr dans la préparation de dérivés quinoliniques, nous a permis de synthétiser des naphtamides qui génèrent, avec de bons rendements, des structures benzoquinoléiques stables. La caractérisation au moyen de techniques spectroscopiques usuelles des produits synthétisés est particulièrement mise en relief dans cet article.

  18. Further exploration of antimicrobial ketodihydronicotinic acid derivatives by multiple parallel syntheses

    DEFF Research Database (Denmark)

    Laursen, Jane B.; Nielsen, Janne; Haack, T.

    2006-01-01

    the most potent compound in this class. Cross-resistance with ciprofloxacin supported a commonality of mode of action. Permiabilization of Escherichia coli cells by polymyxin B significantly enhanced potency with these agents suggesting that poor cellular uptake was primarily responsible...

  19. Inorganic chemistry: Direct syntheses from pure liquid SO3 and from trivalent and pentavalent nitrogen derivatives

    Science.gov (United States)

    Vandorpe, B.; Heubel, J.

    1977-01-01

    From pure liquid SO3 direct synthesis reactions were carried out with N2O5, NO2Cl, NOCl which yielded N2O54SO3, 3SO3, 2SO3-NO2Cl2SO3-NOCl2SO3 and NOCl2SO3, the latter being obtained for the first time in the pure state. In all cases the crystallized product was obtained by separating the constituents of the mixture and then going through a single viscous liquid phase.

  20. The major substrates for TAP in vivo are derived from newly synthesized proteins

    NARCIS (Netherlands)

    Reits, E. A.; Vos, J. C.; Grommé, M.; Neefjes, J.

    2000-01-01

    The transporter associated with antigen processing (TAP) is a member of the family of ABC transporters that translocate a large variety of substrates across membranes. TAP transports peptides from the cytosol into the endoplasmic reticulum for binding to MHC class I molecules and for subsequent

  1. Knockout of GAD65 has major impact on synaptic GABA synthesized from astrocyte-derived glutamine

    DEFF Research Database (Denmark)

    Walls, Anne Byriel; Eyjolfsson, Elvar M.; Smeland, Olav B.

    2011-01-01

    γ-Aminobutyric acid (GABA) synthesis from glutamate is catalyzed by glutamate decarboxylase (GAD) of which two isoforms, GAD65 and GAD67, have been identified. The GAD65 has repeatedly been shown to be important during intensified synaptic activity. To specifically elucidate the significance of GAD......65 for maintenance of the highly compartmentalized intracellular and intercellular GABA homeostasis, GAD65 knockout and corresponding wild-type mice were injected with [1-(13)C]glucose and the astrocyte-specific substrate [1,2-(13)C]acetate. Synthesis of GABA from glutamine in the GABAergic synapses...... was further investigated in GAD65 knockout and wild-type mice using [1,2-(13)C]acetate and in some cases γ-vinylGABA (GVG, Vigabatrin), an inhibitor of GABA degradation. A detailed metabolic mapping was obtained by nuclear magnetic resonance (NMR) spectroscopic analysis of tissue extracts of cerebral cortex...

  2. Comparative syntheses of peptides and peptide thioesters derived from mouse and human prion proteins

    Czech Academy of Sciences Publication Activity Database

    Šebestík, Jaroslav; Zawada, Zbigniew; Šafařík, Martin; Hlaváček, Jan

    2012-01-01

    Roč. 43, č. 3 (2012), s. 1297-1309 ISSN 0939-4451 R&D Projects: GA ČR GA203/07/1517 Institutional research plan: CEZ:AV0Z40550506 Keywords : prion protein segments * classical synthesis * chemical ligation synthesis * peptide thioesters Subject RIV: CC - Organic Chemistry Impact factor: 3.914, year: 2012

  3. Comparative syntheses of peptide thioesters derived from mouse and human prion proteins

    Czech Academy of Sciences Publication Activity Database

    Šebestík, Jaroslav; Zawada, Zbigniew; Šafařík, Martin; Hlaváček, Jan

    2011-01-01

    Roč. 41, Suppl. 1 (2011), S78-S79 ISSN 0939-4451. [International Congress on Amino Acids, Peptides and Proteins /12./. 01.08.2011-05.08.2011, Beijing] R&D Projects: GA ČR GA203/07/1517 Institutional research plan: CEZ:AV0Z40550506 Keywords : peptide thioesters * ligation * prions * C-domain Subject RIV: CC - Organic Chemistry

  4. Antibacterial activity of synthesized 2,4,5-trisubstituted imidazole derivatives

    Digital Repository Service at National Institute of Oceanography (India)

    Khan, M.S.; Siddiqui, S.A.; Siddiqui, M.S.R.A.; Goswami, U.; Srinivasan, K.V.; Khan, M.I.

    release or inhibiting the p38 MAP kinase (1), anti-allergic activity (2) and analgesic activity (3). They are also sensitizers of multidrug-resistant cancer cells (4), pesticides (5), antibiotics (6) or sodium-channel mod- ulators (7). Some imidazole...

  5. Functional polyethylene glycol derivatives nanostructured thin films synthesized by matrix-assisted pulsed laser evaporation

    International Nuclear Information System (INIS)

    Cristescu, R.; Popescu, C.; Popescu, A.; Grigorescu, S.; Mihailescu, I.N.; Mihaiescu, D.; Gittard, S.D.; Narayan, R.J.; Buruiana, T.; Stamatin, I.; Chrisey, D.B.

    2009-01-01

    We report the thin film deposition by matrix-assisted pulsed laser evaporation (MAPLE) of a polymer conjugate with an hydrophilic sequence between metronidazole molecules that was covalently attached to both oligomer ends of carboxylate poly(ethylene glycol) (PEG 1.5-metronidazole). A pulsed KrF* excimer laser was used to deposit the drug-polymer composite films. Fourier transform infrared spectroscopy was used to demonstrate that MAPLE-transferred materials exhibited chemical properties similar to the starting materials. The dependence of the surface morphology on incident laser fluence is given.

  6. Reactions of nitroxides 15. Cinnamates bearing a nitroxyl moiety synthesized using a Mizoroki–Heck cross-coupling reaction

    Directory of Open Access Journals (Sweden)

    Jerzy Zakrzewski

    2015-07-01

    Full Text Available Cinnamic acid derivatives bearing a nitroxyl moiety (2,2,6,6-tetramethyl-1-oxyl-4-piperidyl 3-E-aryl acrylates were synthesized in 30–100% yield using a Mizoroki–Heck cross-coupling reaction between 4-acryloyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl and iodobenzene derivatives in the presence of palladium(II acetate coordinated with a tri(o-tolylphosphine ligand immobilized in a polyurea matrix.

  7. Modification of Lime Mortars with Synthesized Aluminosilicates

    Science.gov (United States)

    Loganina, Valentina I.; Sadovnikova, Marija E.; Jezierski, Walery; Małaszkiewicz, Dorota

    2017-10-01

    The increasing attention for restoration of buildings of historical and architectural importance has increased the interest for lime-based binders, which could be applied for manufacturing repair mortars and plasters compatible with historical heritage. Different additives, admixtures or fibers may be incorporated to improve mechanical and thermal features of such materials. In this study synthesized aluminosilicates (SA) were applied as an additive for lime mortar. The technology of synthesis consisted in the deposition of aluminosilicates from a sodium liquid glass by the aluminum sulphate Al2(SO4)3. The goal of this investigation was developing a new method of aluminosilicates synthesis from a sodium liquid glass and using this new material as a component for a lime mortar. Aluminosilicates were precipitated from the solution of aluminum sulphate Al2(SO)3 and sodium silicate. SA were then used as an additive to calcareous compositions and their influence was tested. Mortars were prepared with commercial air lime and siliceous river sand. Air lime binder was replaced by 5 and 10 wt.% of SA. Calcareous composition specimens were formed at water/lime ratio 1.0. The following analyses were made: grain size distribution of SA, X-ray diffraction analysis (XRD), sorption properties, plastic strength and compressive strength of lime mortars. XRD pattern of the SA shows the presence of thenardite, gibbsite and amorphous phase represented by aggregate of nano-size cristobalite-like crystallites. Application of SA leads to increase of compressive strength after 90 days of hardening by 28% and 53% at SA content 5 and 10% respectively comparing to specimens without this additive. Contents of chemically bound lime in the reference specimens after 28 days of hardening in air-dry conditions was 46.5%, while in specimens modified with SA contained 50.0-55.3% of bound lime depending on filtrate pH. This testifies to high activity of calcareous composition. The new blended lime

  8. Syntheses and electronic structures of decamethylmetallocenes

    International Nuclear Information System (INIS)

    Robbins, J.L.

    1981-04-01

    The synthesis of decamethylmanganocene [(eta-C 5 (CH 3 ) 5 ) 2 Mn or (Me 5 Cp) 2 Mn)] is described. Magnetic susceptibility and electron paramagnetic resonance (EPR) studies show that (Me 5 Cp) 2 Mn is a low-spin, 17-electron compound with an orbitally degenerate, 2 E/sub 2g/ [e/sub 2g/ 3 a/sub 1g/ 2 ] ground state. An x-ray crystallographic study of (Me 5 Cp) 2 Mn shows that it is a monomeric, D/sub 5d/ decamethylmetallocene with metal to ring carbon distances that are about 0.3 A shorter than those determined for high-spin manganocenes. The syntheses of new (Me 5 Cp) 2 M (M = Mg,V,Cr,Co, and Ni) and [(Me 5 Cp) 2 M]PF 6 (M = Cr,Co, and Ni) compounds are described. In addition, a preparative route to a novel, dicationic decamethylmetallocene, [(Me 5 Cp) 2 Ni](PF 6 ) 2 is reported. Infrared, nuclear magnetic resonance, magnetic susceptibility, and/or x-ray crystallographic studies indicate that all the above compounds are D/sub 5d/ or D/sub 5h/ decamethylmetallocenes with low-spin electronic configurations. Cyclic voltammetry studies verify the reversibility and the one-electron nature of the (Me 5 Cp) 2 M → [(Me 5 Cp) 2 M] + (M = Cr,Mn,Fe,Co,Ni), [(Me 5 Cp) 2 Mn] - → (Me 5 Cp) 2 Mn and [(Me 5 Cp) 2 Ni] + → [Me 5 Cp) 2 Ni] 2+ redox reactions. These studies reveal that the neutral decamethylmetallocenes are much more easily oxidized than their metallocene counterparts. This result attests to the electron-donating properties of the ten substituent methyl groups. Proton and carbon-13 NMR data are reported for the diamagnetic Mg(II), Mn(I), Fe(II), Co(III), and Ni(IV) decamethylmetallocenes and for [(Me 5 Cp) 2 V(CO) 2 ] + . The uv-visible absorption spectra of the 15-, 18- and 20- electron decamethylmetallocenes are also reported

  9. Syntheses and electronic structures of decamethylmetallocenes

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, J.L.

    1981-04-01

    The synthesis of decamethylmanganocene ((eta-C/sub 5/(CH/sub 3/)/sub 5/)/sub 2/Mn or (Me/sub 5/Cp)/sub 2/Mn)) is described. Magnetic susceptibility and electron paramagnetic resonance (EPR) studies show that (Me/sub 5/Cp)/sub 2/Mn is a low-spin, 17-electron compound with an orbitally degenerate, /sup 2/E/sub 2g/ (e/sub 2g//sup 3/ a/sub 1g//sup 2/) ground state. An x-ray crystallographic study of (Me/sub 5/Cp)/sub 2/Mn shows that it is a monomeric, D/sub 5d/ decamethylmetallocene with metal to ring carbon distances that are about 0.3 A shorter than those determined for high-spin manganocenes. The syntheses of new (Me/sub 5/Cp)/sub 2/M (M = Mg,V,Cr,Co, and Ni) and ((Me/sub 5/Cp)/sub 2/M)PF/sub 6/ (M = Cr,Co, and Ni) compounds are described. In addition, a preparative route to a novel, dicationic decamethylmetallocene, ((Me/sub 5/Cp)/sub 2/Ni)(PF/sub 6/)/sub 2/ is reported. Infrared, nuclear magnetic resonance, magnetic susceptibility, and/or x-ray crystallographic studies indicate that all the above compounds are D/sub 5d/ or D/sub 5h/ decamethylmetallocenes with low-spin electronic configurations. Cyclic voltammetry studies verify the reversibility and the one-electron nature of the (Me/sub 5/Cp)/sub 2/M ..-->.. ((Me/sub 5/Cp)/sub 2/M)/sup +/ (M = Cr,Mn,Fe,Co,Ni), ((Me/sub 5/Cp)/sub 2/Mn)/sup -/ ..-->.. (Me/sub 5/Cp)/sub 2/Mn and ((Me/sub 5/Cp)/sub 2/Ni)/sup +/ ..-->.. (Me/sub 5/Cp)/sub 2/Ni)/sup 2 +/ redox reactions. These studies reveal that the neutral decamethylmetallocenes are much more easily oxidized than their metallocene counterparts. This result attests to the electron-donating properties of the ten substituent methyl groups. Proton and carbon-13 NMR data are reported for the diamagnetic Mg(II), Mn(I), Fe(II), Co(III), and Ni(IV) decamethylmetallocenes and for ((Me/sub 5/Cp)/sub 2/V(CO)/sub 2/)/sup +/. The uv-visible absorption spectra of the 15-, 18- and 20- electron decamethylmetallocenes are also reported.

  10. Biologically Active Metabolites Synthesized by Microalgae

    Directory of Open Access Journals (Sweden)

    Michele Greque de Morais

    2015-01-01

    Full Text Available Microalgae are microorganisms that have different morphological, physiological, and genetic traits that confer the ability to produce different biologically active metabolites. Microalgal biotechnology has become a subject of study for various fields, due to the varied bioproducts that can be obtained from these microorganisms. When microalgal cultivation processes are better understood, microalgae can become an environmentally friendly and economically viable source of compounds of interest, because production can be optimized in a controlled culture. The bioactive compounds derived from microalgae have anti-inflammatory, antimicrobial, and antioxidant activities, among others. Furthermore, these microorganisms have the ability to promote health and reduce the risk of the development of degenerative diseases. In this context, the aim of this review is to discuss bioactive metabolites produced by microalgae for possible applications in the life sciences.

  11. Biologically Active Metabolites Synthesized by Microalgae.

    Science.gov (United States)

    de Morais, Michele Greque; Vaz, Bruna da Silva; de Morais, Etiele Greque; Costa, Jorge Alberto Vieira

    2015-01-01

    Microalgae are microorganisms that have different morphological, physiological, and genetic traits that confer the ability to produce different biologically active metabolites. Microalgal biotechnology has become a subject of study for various fields, due to the varied bioproducts that can be obtained from these microorganisms. When microalgal cultivation processes are better understood, microalgae can become an environmentally friendly and economically viable source of compounds of interest, because production can be optimized in a controlled culture. The bioactive compounds derived from microalgae have anti-inflammatory, antimicrobial, and antioxidant activities, among others. Furthermore, these microorganisms have the ability to promote health and reduce the risk of the development of degenerative diseases. In this context, the aim of this review is to discuss bioactive metabolites produced by microalgae for possible applications in the life sciences.

  12. Biologically Active Metabolites Synthesized by Microalgae

    Science.gov (United States)

    Costa, Jorge Alberto Vieira

    2015-01-01

    Microalgae are microorganisms that have different morphological, physiological, and genetic traits that confer the ability to produce different biologically active metabolites. Microalgal biotechnology has become a subject of study for various fields, due to the varied bioproducts that can be obtained from these microorganisms. When microalgal cultivation processes are better understood, microalgae can become an environmentally friendly and economically viable source of compounds of interest, because production can be optimized in a controlled culture. The bioactive compounds derived from microalgae have anti-inflammatory, antimicrobial, and antioxidant activities, among others. Furthermore, these microorganisms have the ability to promote health and reduce the risk of the development of degenerative diseases. In this context, the aim of this review is to discuss bioactive metabolites produced by microalgae for possible applications in the life sciences. PMID:26339647

  13. Synthesis, antimicrobial evaluation and QSAR studies of gallic acid derivatives

    Directory of Open Access Journals (Sweden)

    Anurag Khatkar

    2017-05-01

    Full Text Available A series of gallic acid derivatives (1–33 was synthesized and characterized by physicochemical and spectral means. The synthesized compounds were evaluated in vitro for their antimicrobial activity against different Gram positive and Gram negative bacterial and fungal strains by the tube dilution method. Results of antimicrobial screening indicated that compound 6 was the most active antimicrobial agent (pMICam = 1.92 μM/mL. The results of QSAR studies demonstrated that antibacterial, antifungal and overall antimicrobial activities of synthesized gallic acid derivatives were governed by the electronic parameters, cosmic total energy (Cos E. and nuclear energy (Nu. E..

  14. Novel hydroquinone derivatives alleviate algesia, inflammation and ...

    African Journals Online (AJOL)

    The in silico studies predicted high binding affinity of the hydroquinone derivatives to the active site of the cyclooxygenase 2 (COX-2) enzyme. Conclusion: The synthesized hydroquinone compounds possess analgesic, antipyretic and antiinflammatory properties with low gastric-ulcerogenic potential. This may be credited to ...

  15. Synthesis and characterization of novel sulfonamides derivatives ...

    African Journals Online (AJOL)

    Five novel sulfonamides derivatives HR5-HR8 and HR14 were synthesized by sulfonylation of primary or secondary amine in the presence of base through nucleophilic substitution reaction. Structural elucidation was carried out through FT-IR, UV, 1H NMR, MS and elemental analysis. Prepared compounds were evaluated ...

  16. Synthesis and Topoisomerase I inhibitory properties of klavuzon derivatives.

    Science.gov (United States)

    Akçok, İsmail; Mete, Derya; Şen, Ayhan; Kasaplar, Pınar; Korkmaz, Kemal S; Çağır, Ali

    2017-04-01

    Klavuzon is a naphthalen-1-yl substituted α,β-unsaturated δ-lactone derivative, and is one of the anti-proliferative members of this class of compounds. Asymmetric and racemic syntheses of novel α,β-unsaturated δ-lactone derivatives are important to investigate their potential for the treatment of cancer. In this study, asymmetric and racemic syntheses of heteroatom-substituted klavuzon derivatives are reported. The syntheses were completed by a well-known three-step procedure. Anti-proliferative activity of seven novel racemic klavuzon derivatives were reported against MCF-7, PC3, HCT116 p53+/+ and HCT116 p53-/- cancer cell lines. Topoisomerase I inhibitory properties of 5,6-dihydro-2H-pyran-2-one derivatives were also studied. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Synthesis of Substituted α-Trifluoromethyl Piperidinic Derivatives

    Directory of Open Access Journals (Sweden)

    Sarah Rioton

    2017-03-01

    Full Text Available A comprehensive survey of pathways leading to the generation of α-trifluoromethyl monocyclic piperidinic derivatives is provided (65 references. These compounds have been synthesized either from 6-membered rings e.g., pipecolic acid or lactam derivatives by introduction a trifluoromethyl group, from pyridine or pyridinone derivatives by reduction, and from 5-membered rings e.g., prolinol derivatives by ring expansion, from linear amines by cyclization or from dienes/dienophiles by [4 + 2]-cycloaddition.

  18. Chalcone derivatives as potential antifungal agents: Synthesis, and antifungal activity

    Directory of Open Access Journals (Sweden)

    Deepa Gupta

    2015-01-01

    Full Text Available Much research has been carried out with the aim to discover the therapeutic values of chalcone derivatives. Chalcones possess wide range of pharmacological activity such as antibacterial, antimalarial, antiprotozoal, antitubercular, anticancer, and antifungal agents etc. The presence of reactive α,β-unsaturated keto group in chalcones is found to be responsible for their biological activity. The rapid developments of resistance to antifungal agents, led to design, and synthesize the new antifungal agents. The derivatives of chalcones were prepared using Claisen-Schmidt condensation scheme with appropriate tetralone and aldehyde derivatives. Ten derivatives were synthesized and were biologically screened for antifungal activity. The newly synthesized derivatives of chalcone showed antifungal activity against fungal species, Microsporum gypseum. The results so obtained were superior or comparable to ketoconazole. It was observed that none of the compounds tested showed positive results for fungi Candida albicans nor against fungi Aspergillus niger. Chalcone derivatives showed inhibitory effect against M. gypseum species of fungus. It was found that among the chalcone derivatives so synthesized, two of them, that is, 4-chloro derivative, and unsubstituted derivative of chalcone showed antifungal activity superior to ketoconazole. Thus, these can be the potential new molecule as antifungal agent.

  19. Syntheses and absorption-structure relationships of some new ...

    Indian Academy of Sciences (India)

    New biheterocyclic compound was synthesized as starting material to prepare new photosensitizers mono-, tri-, substituted tri-, azadimethine and mixed cyanine dyes. Absorption-structure relationship of the synthesized cyanine dyes were determined by studying their electronic spectral behaviour in ethanol. The structure of ...

  20. Biogenic ZnO nanoparticles synthesized using L. aculeata leaf ...

    Indian Academy of Sciences (India)

    Abstract. In this study, Zinc oxide (ZnO) nanoparticles were synthesized using aqueous extract of Lantana aculeata. Linn. leaf and assessed their effects on antifungal activity against the plant fungal pathogens. Synthesized nanoparti- cles were confirmed by ultraviolet–visible spectroscopy, Fourier transform infrared ...

  1. Syntheses and absorption–structure relationships of some new ...

    Indian Academy of Sciences (India)

    New biheterocyclic compound was synthesized as starting material to prepare new photosensitizers mono-, tri-, substituted tri-, azadimethine and mixed cyanine dyes. Absorption-structure relationship of the synthesized cyanine dyes were determined by studying their electronic spectral behaviour in ethanol. The structure of ...

  2. Comparative study of synthesized silver and gold nanoparticles ...

    Indian Academy of Sciences (India)

    Nanotechnology is an emerging field in science and technology, which can be applied to synthesize new materials at the nanoscale level. The present investigation aimed at comparing the synthesis, characterization andin vitro anticancer efficacy of synthesized silver and gold nanoparticles using leaves extract of Bauhinia ...

  3. Potentiometric study of polyaniline film synthesized with various ...

    Indian Academy of Sciences (India)

    The potentiometric study of polyaniline (PANI) film synthesized with dopants viz. polyvinyl sulfonic acid (PVS), -toluene sulfonic acid (TS), dodecyl benzene sulfonic acid (DBS) and composite-dopants viz. PVS–TS and PVS–DBS, has been carried out. The synthesized PANI films were characterized by electrochemical ...

  4. Biogenic ZnO nanoparticles synthesized using L. aculeata leaf ...

    Indian Academy of Sciences (India)

    In this study, Zinc oxide (ZnO) nanoparticles were synthesized using aqueous extract of Lantana aculeata Linn. leaf and assessed their effects on antifungal activity against the plant fungal pathogens. Synthesized nanoparticles were confirmed by ultraviolet–visible spectroscopy, Fourier transform infrared spectrometer, ...

  5. Antiproliferative activity of synthesized some new benzimidazole carboxamidines against MCF-7 breast carcinoma cells.

    Science.gov (United States)

    Karaaslan, Cigdem; Bakar, Filiz; Goker, Hakan

    2018-02-23

    Breast cancer is the most endemic cause of cancer among women in both developed and developing countries. Benzimidazole derivatives exemplify one of the chemical classes that show strong cytotoxic activity especially against breast cancer cells (MCF-7). Aromatic amidine derivatives are known as a group of DNA interactive compounds that bind minor groove of the genome, especially A-T base pairs, and show significant in vitro and in vivo toxicity toward cancer cells. In light of these studies, some new mono/dicationic amidino benzimidazole derivatives were synthesized and evaluated for cytotoxic activity on cultured MCF-7 breast cancer cells. Some of these compounds have strongly inhibited MCF-7 cell viability in a dose-dependent manner compared with clinically used reference compounds, imatinib mesylate and docetaxel. Among them, 4-[(5(6)-bromo-1H-benzimidazole-2-yl)amino]benzene-1-carboxamidine (30) showed the best inhibitory activity with IC50 value of 4.6 nM.

  6. Anode behaviors of aluminum antimony synthesized by mechanical alloying for lithium secondary battery

    International Nuclear Information System (INIS)

    Honda, H.; Sakaguchi, H.; Fukuda, Y.; Esaka, T.

    2003-01-01

    AlSb was synthesized as an anode active material for lithium secondary battery using mechanical alloying (MA). Electrochemical performance was examined on the electrodes of AlSb synthesized with different MA time. The first charge (lithium-insertion) capacity of the AlSb electrodes decreased with increasing the MA time. The discharge capacity on repeating charge-discharge cycle, however, did not show the same dependence. The electrode, consisting of the 20 h MA sample exhibited the longest charge-discharge life cycle, suggesting that there is the optimum degree of internal energy derived from the strain and/or the amorphization due to mechanical alloying. These results were evaluated using ex situ X-ray diffraction and differential scanning calorimetry

  7. A NOVEL ACRYLONITRILE DERIVATIVE HAVING PHOTOVOLTAIC PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Cigdem Yorur-Goreci

    2016-10-01

    Full Text Available A new acrylonitrile derivative 3 (BPCPFA which offer potential application as organic solar cell material was synthesized with three steps. The structures of the molecules synthesized in these steps were characterized using various spectral analyses. BPCPFA was investigated as an electron acceptor molecule in next generation organic solar cells. Theoretical prediction and experimental studies for photovoltaic performance were performed. Based on these results, it is concluded that BPCPFA with extended conjugated system has good and promising photovoltaic performance with Voc value as 0.96 V.

  8. Synthesis and Biological Evaluation of Some Pyridine Derivatives as ...

    African Journals Online (AJOL)

    Synthesis and Biological Evaluation of Some Pyridine Derivatives as Antimicrobial Agents. ... Ethiopian Pharmaceutical Journal ... In this study, several pyridine derivatives were synthesized and evaluated for their in vitro antimicrobial activity against Gram-positive bacteria (Bacillus cereus and Staphylococcus aureus), ...

  9. Synthesis and bioactivity of rotenone oxime O -ether derivatives ...

    African Journals Online (AJOL)

    A series of rotenone oxime O-ether derivatives were synthesized and characterized. All compounds were tested for their insecticidal, miticidal and fungicidal activities against the selected pests and compared with those of rotenone. The results of biological tests show that the rotenone oxime O-ether derivatives have ...

  10. Synthesis and anticancer evaluation of imidazolinone and benzoxazole derivatives

    Directory of Open Access Journals (Sweden)

    Heba A. El-Hady

    2017-05-01

    Full Text Available A series of imidazolinone and benzoxazole derivatives (3 and 5 have been synthesized by the condensation of oxazolinone derivatives (2a–c with aniline and 2-hydroxyaniline. Acetyl derivatives (4, 6 and 7 were prepared via acetylation of compounds 3 and 5 with acetic anhydride and chloroacetyl chloride. The results revealed that imidazolinone and benzoxazole derivatives are potent against the cancer cell lines MCF-7 and HePG2. In particular, benzoxazole derivatives are more potent than imidazolinone derivatives.

  11. Syntheses of strychnine, norfluorocurarine, dehydrodesacetylretuline, and valparicine enabled by intramolecular cycloadditions of Zincke aldehydes.

    Science.gov (United States)

    Martin, David B C; Nguyen, Lucas Q; Vanderwal, Christopher D

    2012-01-06

    A full account of the development of the base-mediated intramolecular Diels-Alder cycloadditions of tryptamine-derived Zincke aldehydes is described. This important complexity-generating transformation provides the tetracyclic core of many indole monoterpene alkaloids in only three steps from commercially available starting materials and played a key role in short syntheses of norfluorocurarine (five steps), dehydrodesacetylretuline (six steps), valparicine (seven steps), and strychnine (six steps). Reasonable mechanistic possibilities for this reaction, a surprisingly facile dimerization of the products, and an unexpected cycloreversion to regenerate Zincke aldehydes under specific conditions are also discussed.

  12. GaN Nanowires Synthesized by Electroless Etching Method

    KAUST Repository

    Najar, Adel

    2012-01-01

    Ultra-long Gallium Nitride Nanowires is synthesized via metal-electroless etching method. The morphologies and optical properties of GaN NWs show a single crystal GaN with hexagonal Wurtzite structure and high luminescence properties.

  13. Syntheses, structures and properties of two dinuclear mercury(II ...

    Indian Academy of Sciences (India)

    Syntheses, structures and properties of two dinuclear mercury(II) iodide compounds containing tetradentate tripodal amine/pentadentate. N-donor Schiff base: Control of molecular and crystalline architectures by varying ligand matrices. SUBHASIS ROYa, SOUMI CHATTOPADHYAYa, SOMNATH CHOUBEYa,. KISHALAY ...

  14. La Baie de Seine: Utilisation, environnement. Synthese des discussions

    OpenAIRE

    Mauvais, J

    1985-01-01

    This report synthesizes the communications about the processes set in motion or accelerated by man's actions in the Seine Bay. They are grouped in three categories: fishing and pollution and estuarine equipment; colored waters and pollution; and estuarine equipment.

  15. Characterization of combustion synthesized zirconia powder by UV

    Indian Academy of Sciences (India)

    . The surface acidbase properties of these samples were also investigated by indicator titration method. The catalytic activity was probed with transfer hydrogenation reaction in liquid phase. It was found that combustion synthesized zirconia did ...

  16. Synthesis of C3-symmetric and C4-symmetric amino acid derivatives via Suzuki-Miyaura cross-coupling reaction.

    Science.gov (United States)

    Kotha, S; Shah, V R

    2008-06-01

    Various non-natural C(3)- and C(4)-symmetric alpha-amino acid derivatives have been synthesized via Suzuki-Miyaura cross-coupling reaction between aromatic iodides or bromide and a suitably protected DL-4-boronophenylalanine derivative.

  17. Synthesizing genetic sequential logic circuit with clock pulse generator

    OpenAIRE

    Chuang, Chia-Hua; Lin, Chun-Liang

    2014-01-01

    Background Rhythmic clock widely occurs in biological systems which controls several aspects of cell physiology. For the different cell types, it is supplied with various rhythmic frequencies. How to synthesize a specific clock signal is a preliminary but a necessary step to further development of a biological computer in the future. Results This paper presents a genetic sequential logic circuit with a clock pulse generator based on a synthesized genetic oscillator, which generates a consecut...

  18. Perceptual Error Analysis of Human and Synthesized Voices.

    Science.gov (United States)

    Englert, Marina; Madazio, Glaucya; Gielow, Ingrid; Lucero, Jorge; Behlau, Mara

    2017-07-01

    To assess the quality of synthesized voices through listeners' skills in discriminating human and synthesized voices. Prospective study. Eighteen human voices with different types and degrees of deviation (roughness, breathiness, and strain, with three degrees of deviation: mild, moderate, and severe) were selected by three voice specialists. Synthesized samples with the same deviations of human voices were produced by the VoiceSim system. The manipulated parameters were vocal frequency perturbation (roughness), additive noise (breathiness), increasing tension, subglottal pressure, and decreasing vocal folds separation (strain). Two hundred sixty-nine listeners were divided in three groups: voice specialist speech language pathologists (V-SLPs), general clinician SLPs (G-SLPs), and naive listeners (NLs). The SLP listeners also indicated the type and degree of deviation. The listeners misclassified 39.3% of the voices, both synthesized (42.3%) and human (36.4%) samples (P = 0.001). V-SLPs presented the lowest error percentage considering the voice nature (34.6%); G-SLPs and NLs identified almost half of the synthesized samples as human (46.9%, 45.6%). The male voices were more susceptible for misidentification. The synthesized breathy samples generated a greater perceptual confusion. The samples with severe deviation seemed to be more susceptible for errors. The synthesized female deviations were correctly classified. The male breathiness and strain were identified as roughness. VoiceSim produced stimuli very similar to the voices of patients with dysphonia. V-SLPs had a better ability to classify human and synthesized voices. VoiceSim is better to simulate vocal breathiness and female deviations; the male samples need adjustment. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  19. Proteins synthesized in tobacco mosaic virus infected protoplasts

    International Nuclear Information System (INIS)

    Huber, R.

    1979-01-01

    The author deals with research on the multiplication of tobacco mosaic virus (TMV) in leaf cell protoplasts. An attempt is made to answer three questions: (1) Which proteins are synthesized in TMV infected protoplasts as a result of TMV multiplication. (2) Which of the synthesized proteins are made under the direction of the TMV genome and, if any, which of the proteins are host specific. (3) In which functions are these proteins involved. (Auth.)

  20. Piroxicam derivatives THz classification

    Science.gov (United States)

    Sterczewski, Lukasz A.; Grzelczak, Michal P.; Nowak, Kacper; Szlachetko, Bogusław; Plinska, Stanislawa; Szczesniak-Siega, Berenika; Malinka, Wieslaw; Plinski, Edward F.

    2016-02-01

    In this paper we report a new approach to linking the terahertz spectral shapes of drug candidates having a similar molecular structure to their chemical and physical parameters. We examined 27 newly-synthesized derivatives of a well-known nonsteroidal anti-inflammatory drug Piroxicam used for treatment of inflammatory arthritis and chemoprevention of colon cancer. The testing was carried out by means of terahertz pulsed spectroscopy (TPS). Using chemometric techniques we evaluated their spectral similarity in the terahertz range and attempted to link the position on the principal component analysis (PCA) score map to the similarity of molecular descriptors. A simplified spectral model preserved 75% and 85.1% of the variance in 2 and 3 dimensions respectively, compared to the input 1137. We have found that in 85% of the investigated samples a similarity of the physical and chemical parameters corresponds to a similarity in the terahertz spectra. The effects of data preprocessing on the generated maps are also discussed. The technique presented can support the choice of the most promising drug candidates for clinical trials in pharmacological research.

  1. Computer Assisted Design, Prediction, and Execution of Economical Organic Syntheses

    Science.gov (United States)

    Gothard, Nosheen Akber

    The synthesis of useful organic molecules via simple and cost-effective routes is a core challenge in organic chemistry. In industry or academia, organic chemists use their chemical intuition, technical expertise and published procedures to determine an optimal pathway. This approach, not only takes time and effort, but also is cost prohibitive. Many potential optimal routes scratched on paper fail to get experimentally tested. In addition, with new methods being discovered daily are often overlooked by established techniques. This thesis reports a computational technique that assist the discovery of economical synthetic routes to useful organic targets. Organic chemistry exists as a network where chemicals are connected by reactions, analogous to citied connected by roads in a geographic map. This network topology of organic reactions in the network of organic chemistry (NOC) allows the application of graph-theory to devise algorithms for synthetic optimization of organic targets. A computational approach comprised of customizable algorithms, pre-screening filters, and existing chemoinformatic techniques is capable of answering complex questions and perform mechanistic tasks desired by chemists such as optimization of organic syntheses. One-pot reactions are central to modern synthesis since they save resources and time by avoiding isolation, purification, characterization, and production of chemical waste after each synthetic step. Sometimes, such reactions are identified by chance or, more often, by careful inspection of individual steps that are to be wired together. Algorithms are used to discover one-pot reactions and validated experimentally. Which demonstrate that the computationally predicted sequences can indeed by carried out experimentally in good overall yields. The experimental examples are chosen to from small networks of reactions around useful chemicals such as quinoline scaffolds, quinoline-based inhibitors of phosphoinositide 3-kinase delta (PI3

  2. Investigations on Structural and Optical Properties of Hydrothermally Synthesized Zn2SnO4 Nanoparticles

    Directory of Open Access Journals (Sweden)

    L. Allwin Joseph

    2016-01-01

    Full Text Available Ternary oxide Zn2SnO4 has emerged as a promising material due to its tunable work function, band gap energy, and electric resistivity by simply varying the composition of the material. Zinc stannate nanoparticles were synthesized by green hydrothermal growth technique at 200°C for the reaction time of 24 h using stannic chloride pentahydrate (SnCl4·5H2O and zinc chloride (ZnCl2 as precursors maintained at pH value of 8. X-ray diffraction analysis confirmed the phase purity and high crystalline nature of the synthesized sample. The estimated crystallite size was about 12.3 nm corresponding to the most prominent plane (311 using Scherrer equation. Morphology of the sample was characterized by SEM analysis, which confirmed the presence of small size nanoparticles. The optical property of synthesized sample was studied by using UV-visible and PL spectroscopy analysis. The derived optical band gap of 3.94 eV was found to be blue shifted as compared to bulk Zn2SnO4 (3.6 eV, which should be attributed to the quantum size effects. Room temperature photoluminescence spectrum showed emission bands at 397 nm and 468 nm.

  3. Perceptual Error Identification of Human and Synthesized Voices.

    Science.gov (United States)

    Englert, Marina; Madazio, Glaucya; Gielow, Ingrid; Lucero, Jorge; Behlau, Mara

    2016-09-01

    To verify the discriminatory ability of human and synthesized voice samples. This is a prospective study. A total of 70 subjects, 20 voice specialist speech-language pathologists (V-SLPs), 20 general SLPs (G-SLPs), and 30 naive listeners (NLs) participated of a listening task that was simply to classify the stimuli as human or synthesized. Samples of 36 voices, 18 human and 18 synthesized vowels, male and female (9 each), with different type and degree of deviation, were presented with 50% of repetition to verify intrarater consistency. Human voices were collected from a vocal clinic database. Voice disorders were simulated by perturbations of vocal frequency, jitter (roughness), additive noise (breathiness) and by increasing tension and decreasing separation of the vocal folds (strain). The average amount of error considering all groups was 37.8%, 31.9% for V-SLP, 39.3% for G-SLP, and 40.8% for NL. V-SLP had smaller mean percentage error for synthesized (24.7%), breathy (36.7%), synthesized breathy (30.8%), and tense (25%) and female (27.5%) voices. G-SLP and NL presented equal mean percentage error for all voices classification. All groups together presented no difference on the mean percentage error between human and synthesized voices (P value = 0.452). The quality of synthesized samples was very high. V-SLP presented a lower amount of error, which allows us to infer that auditory training assists on vocal analysis tasks. Copyright © 2016 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  4. Synthesization of high-capacity auto-associative memories using complex-valued neural networks

    Science.gov (United States)

    Huang, Yu-Jiao; Wang, Xiao-Yan; Long, Hai-Xia; Yang, Xu-Hua

    2016-12-01

    In this paper, a novel design procedure is proposed for synthesizing high-capacity auto-associative memories based on complex-valued neural networks with real-imaginary-type activation functions and constant delays. Stability criteria dependent on external inputs of neural networks are derived. The designed networks can retrieve the stored patterns by external inputs rather than initial conditions. The derivation can memorize the desired patterns with lower-dimensional neural networks than real-valued neural networks, and eliminate spurious equilibria of complex-valued neural networks. One numerical example is provided to show the effectiveness and superiority of the presented results. Project supported by the National Natural Science Foundation of China (Grant Nos. 61503338, 61573316, 61374152, and 11302195) and the Natural Science Foundation of Zhejiang Province, China (Grant No. LQ15F030005).

  5. Triazolyl tryptoline derivatives as β-secretase inhibitors

    OpenAIRE

    Jiaranaikulwanitch, Jutamas; Boonyarat, Chantana; Fokin, Valery V.; Vajragupta, Opa

    2010-01-01

    Tryptoline, a core structure of ochrolifuanine E, which is a hit compound from virtual screening of the Thai herbal database against BACE1 was used as a scaffold for the design of BACE1 inhibitors. The tryptoline was linked with different side chains by 1,2,3-triazole ring readily synthesized by catalytic azide-alkyne cycloaddition reactions. Twenty two triazolyl tryptoline derivatives were synthesized and screened for the inhibitory action against BACE1. JJCA-140 was the most potent inhibito...

  6. Synthesis of chalcone incorporated quinazoline derivatives as anticancer agents

    Directory of Open Access Journals (Sweden)

    Sapavat Madhavi

    2017-02-01

    Full Text Available A series of ten novel chalcone incorporated quinazoline derivatives (11a–11j were designed and synthesized. All the synthesized compounds were evaluated for their anticancer activities against four human cancer cell lines (A549, HT-29, MCF-7 and A375. Among them, four compounds, 11f, 11g, 11i and 11j showed more potent anticancer activity than the control drug, Combretastatin – A4.

  7. Antileishmanial activity of polycyclic derivatives

    Directory of Open Access Journals (Sweden)

    Sarciron M.E.

    2005-09-01

    Full Text Available 33 polycyclic derivatives have been studied and tested on Leishmania donovani and L. major promastigotes. Their antileishmanial activity was assessed in vitro and an assay of their cytotoxicity was realized on human myelomonocytic cell line. The reference molecules used in the assays were amphotericin B and pentamidine. Among the compounds tested, 29 possess an antileishmanial activity; 25 of those were more active against L. donovani than amphotericin B, and nine were as effective as amphotericin B against L. major. Many synthesized derivatives were more active against L.donovani than against L. major. The cytotoxicity studies have shown that among the thirty-three derivatives tested, 12 molecules have an IC50 towards THP-1 cells about equal than that reference drugs, the 21 other derivatives are much less toxic. A 3D QSAR study was undertaken and has permitted to predict activity against L. donovani and L. major and to highlight critical area to optimize activity against the two species.

  8. Synthesizing value-added products from methane by a new Methylomonas.

    Science.gov (United States)

    Guo, W; Li, D; He, R; Wu, M; Chen, W; Gao, F; Zhang, Z; Yao, Y; Yu, L; Chen, S

    2017-11-01

    Methane and methanol are potential carbon sources of industrial micro-organisms in addition to crop-derived bio-carbon sources. Methanotrophs that can utilize these simple, stable and large amounts chemicals are expected to be developed into 'cell factories' for the production of specific chemicals. In this study, a methanotroph that can synthesize lycopene, C 30 carotenoid and exopolysaccharides (EPS) with relative better performances from C1 substrates was isolated, and its performances were evaluated. The isolated strain was identified as Methylomonas sp. ZR1 based on 16S rRNA sequence analysis. Its maximum specific growth rate achieved 0·200 h -1 under flask culture conditions, and 0·386 h -1 in bubble column reactors. ZR1 was able to utilize 35 g l -1 of methanol and even exhibited slight growth in the presence of 40 g l -1 of methanol. Furthermore, ZR1 was proved to synthesize lycopene (C 40 carotenoids) besides the C 30 carotenoids through HPLC-DAD and HPLC-MS/MS analysis methods. Its carotenoid extracts exhibited excellent antioxidative activities measured by the ABTS + method. Plenty of polysaccharides were also synthesized by ZR1, the components of the polysaccharides were identified as glucose, mannose and galactose with a proportion of 1 : 2 : 1 by GC-MS, and its yield achieved 0·13 g g -1 cell dry weight. The isolated strain has great potential for the production of value-added bioproducts from C1 compounds because of its excellent C1 substrate utilizing abilities and its abilities to naturally synthesize lycopene, C 30 carotenoids and EPS. In this study, we isolated a fast-growing methanotroph, its C1 carbon substrate utilizing ability is excellent in comparison with reported methanotrophs. Furthermore, besides polysaccharides and C 30 carotenoids which were commonly synthesized by methanotrophs, our findings suggested that C 40 lycopene could also be naturally synthesized from methane by methanotrophs. © 2017 The Society for Applied

  9. Thermal and optical characterization of biologically synthesized ZnS nanoparticles synthesized from an endophytic fungus Aspergillus flavus: A colorimetric probe in metal detection

    Science.gov (United States)

    Uddandarao, Priyanka; Balakrishnan, Raj Mohan

    2017-03-01

    Nanostructured semiconductor materials are of great importance for several technological applications due to their optical and thermal properties. The design and fabrication of metal sulfide nanoparticles with tunable properties for advanced applications have drawn a great deal of attention in the field of nanotechnology. ZnS is a potential II-IV group material which is used in hetero-junction solar cells, light emitting diodes, optoelectronic devices, electro luminescent devices and photovoltaic cells. Due to their multiple applications, there is a need to elucidate their thermal and optical properties. In the present study, thermal and optical properties of biologically synthesized ZnS nanoparticles are determined in detail with Thermal Gravimetric Analysis (TGA), Derivative Thermogravimetric Analysis (DTG), Differential Scanning Calorimeter (DSC), Diffuse Reflectance Spectroscopy (DRS), Photoluminescence (PL) and Raman spectroscopy. The results reveal that ZnS NPs exhibit a very strong quantum confinement with a significant increase in their optical band gap energy. These biologically synthesized ZnS NPs contain protein residues that can selectively bind with metal ions in aqueous solutions and can exhibit an aggregation-induced color change. This phenomenon is utilized to quantitatively measure the metal concentrations of Cu2 + and Mn2 + in this study. Further the stability of nanoparticles for the metal sensing process is accessed by UV-Vis spectrometer, zeta potential and cyclic voltammeter. The selectivity and sensitivity of ZnS NPs indicate its potential use as a sensor for metal detection in the ecosystem.

  10. Synthesis, antimicrobial and antioxidative activity of some new isatin derivatives

    Directory of Open Access Journals (Sweden)

    Šekularac Gavrilo M.

    2014-01-01

    Full Text Available The isatin derivatives, Schiff bases, were synthesized by the reaction of isatin and various substituted primary amines and characterized by several spectroscopic methods. Investigation of the antimicrobial activity of the synthesized compounds was performed by the agar dilution method, against different strains of bacteria and one fungi. The antioxidative activity of the synthesized compounds was also determined. Some of the compounds have shown the significant activity against the selected strains of microorganisms and the antioxidative activity. [Projekat Ministarstva nauke Republike Srbije, br. 172013 i III 46010

  11. Hardness characteristic of dental porcelain synthesized from Indonesian natural sand

    Science.gov (United States)

    Gunawan, J.; Taufik, D.; Takarini, V.; Hasratiningsih, Z.; Ramelan, A.

    2018-02-01

    Porcelain has been one of dental biomaterials which can be used to restore tooth structure. Veneer and jacket crown were the examples of dental porcelain restoration. Since wear resistance is related to the strength on its surface, then Vickers Hardness Test of the synthesized porcelain was applied subsequently. If the porcelain hardness number is too high, it should be considered that an abrasion of the opposing teeth could occur. On previous research, dental porcelain had been successfully synthesized from Indonesian natural sand. In this experiment, 5 samples were prepared from a mixture of 65w/o Pangaribuan feldspar, 25w/o Belitung silica, 5w/o Sukabumi kaolinite, and 5w/o potassium salt. This synthesized porcelain samples were invested on 5 cm diameter resin each. A kilogram of load was placed on top of each sample for 10 seconds on 7 different indented areas using ZwickRoell Indentec ZHVμ Micro Vickers. The average hardness number of synthesized dental porcelain made from Indonesian natural sand was 936.06 VHN which was higher than the average hardness number of porcelain restoration. In conclusion of the hardness test, synthesized dental porcelain made from Indonesian natural sand can potentially be used as a core, which shall support hardness and strength of the crown restoration.

  12. Diffusion of water and ethanol in silicalite crystals synthesized in fluoride media

    KAUST Repository

    Zhang, Ke

    2013-04-01

    Diffusion of water and ethanol in silicalite has been studied in large crystals (70 μm × 30 μm × 15 μm) synthesized via a fluoride mediated route. The near-perfect hydrophobic silicalite (F-) crystals have very few internal silanol defects and, as a result, display water and ethanol transport behavior that is uncontaminated by these defects. The transport diffusivity (Dt) of ethanol is higher than that of water at the same sorbate activity. However, this difference is due to the difference in the shape of the isotherms. The thermodynamically corrected diffusivity (D o) of water is almost an order of magnitude higher than that of ethanol reflecting the difference in molecular size. Estimates of the permeability/permselectivity/separation factors for ethanol/water separation based on the present kinetic and equilibrium data for the fluoride synthesized crystals are compared with the values observed for traditional silicalite membranes. The present diffusivity values for fluoride synthesized silicalite are similar to the values for regular silicalite (OH-) derived from uptake rate measurements but much smaller (by more than four orders of magnitude) than the self-diffusivities derived from PFG-NMR measurements. This result is consistent with the results of other measurements of the diffusion of small molecules in silicalite which suggest that, in macroscopic measurements, the rate of intra-crystalline transport is controlled by the sub-structure (extensive twinning), rather than by diffusion in the ideal MFI micropores. In this situation microscale measurements such as PFG-NMR will lead to erroneously high estimates of transport rates and therefore of permeability and permselectivity. © 2012 Elsevier Inc. All rights reserved.

  13. Dimension and deriving manner for derived quantities

    International Nuclear Information System (INIS)

    Zhao Zhixiang

    1993-01-01

    Most physical quantities we are interested in are derived from some directly measured physical quantities. To obtain correct least-square result in derived quantity space, one must pay attention to inconsistencies problem to avoid ppp phenomenon in generating derived quantities and their covariance matrix. The situation is complicated by the problems of dimension and deriving manner for derived quantities. Some more general problems, which are independent of ppp, are discussed

  14. Alkylation of Zwitterionic Thiooxalic Acid Derivatives

    Directory of Open Access Journals (Sweden)

    Manfred Michalik

    2001-05-01

    Full Text Available The new S-alkyl thiooxal-1-hydrazono-2-amidrazonium halides 2-4 were synthesized by reaction of the corresponding zwitterionic thiooxalic acid derivatives 1 with alkyl halides in methanol. The structures of compounds 4b and 4d were proven by X-ray structural analysis. Both compounds form an interesting intermolecular network of hydrogen bonds in the solid state.

  15. Synthesis and anticonvulsant properties of tetrahydroisoquinoline derivatives.

    Science.gov (United States)

    Gitto, Rosaria; Caruso, Roberta; Orlando, Valerie; Quartarone, Silvana; Barreca, Maria Letizia; Ferreri, Guido; Russo, Emilio; De Sarro, Giovambattista; Chimirri, Alba

    2004-01-01

    As a follow up of our previous structure-activity relationship and molecular modeling studies, we synthesized a novel series of 1-aryl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline derivatives as potential non-competitive AMPA receptor antagonists. When tested for their ability to prevent sound-induced seizures in DBA/2 mice, some of these novel compounds showed high anticonvulsant potency.

  16. A low-power CMOS frequency synthesizer for GPS receivers

    International Nuclear Information System (INIS)

    Yu Yunfeng; Xiao Shimao; Zhuang Haixiao; Ma Chengyan; Ye Tianchun; Yue Jianlian

    2010-01-01

    A low-power frequency synthesizer for GPS/Galileo L1/E1 band receivers implemented in a 0.18 μm CMOS process is introduced. By adding clock-controlled transistors at latch outputs to reduce the time constant at sensing time, the working frequency of the high-speed source-coupled logic prescaler supplying quadrature local oscillator signals has been increased, compared with traditional prescalers. Measurement results show that this synthesizer achieves an in-band phase noise of -87 dBc/Hz at 15 kHz offset, with spurs less than -65 dBc. The whole synthesizer consumes 6 mA in the case of a 1.8 V supply, and its core area is 0.6 mm 2 . (semiconductor integrated circuits)

  17. Free radicals in irradiated polyacrylonitrile synthesized under high pressure

    International Nuclear Information System (INIS)

    Aneli, D.N.; Topchiashvili, M.I.

    1986-01-01

    Using as an example polyacrylonitrile (PAN), the effect of structural differences between polymers synthesized under different hydrostatic pressures on the formation and properties of free radicals in irradiated polymers is investigated. PAN was irradiated by 60 Co γ-radiation with the dose rate 0.9 mrad/H at 77 and 300 K. All PAN samples, irradiated at 77 K, provided similar ESR spectra. Free radicals, formed in PAN, γ-irradiated at 300 K and synthesized at high pressures (to 500 MPa), differ considerably as to the storing concentration, and stability from free radicals in PAN, synthesized at atmospheric pressure. The higher the PAN synthesis temperature is, the lower is their threshold concentration

  18. Squid photoreceptor terminals synthesize calexcitin, a learning related protein.

    Science.gov (United States)

    Eyman, Maria; Crispino, Marianna; Kaplan, Barry B; Giuditta, Antonio

    2003-08-14

    Nerve endings of squid photoreceptor neurons generate large synaptosomes upon homogenization of the optic lobe. Using several independent methods, these presynaptic structures have been shown to synthesize a wealth of soluble, cytoskeletal and nuclear encoded mitochondrial proteins, and to account for essentially all the translation activity of the synaptosomal fraction. We are now presenting evidence that calexcitin, a learning related, Ca(2+)-binding protein of the B photoreceptors of Hermissenda crassicornis (a mollusk), is synthesized and subjected to post-translational modifications in the squid photoreceptor terminals. In view of the essential role of presynaptic protein synthesis in long-term memory formation in Aplysia, our data suggest that a comparable role may be played by calexcitin synthesized in the squid photoreceptor terminals.

  19. New coumarin derivatives as carbonic anhydrase inhibitors.

    Science.gov (United States)

    Karataş, Mert Olgun; Alici, Bülent; Cakir, Umit; Cetinkaya, Engin; Demir, Dudu; Ergün, Adem; Gençer, Nahit; Arslan, Oktay

    2014-06-01

    In the current study, a series of 4-chloromethyl-7-hydroxy-coumarin derivatives containing imidazolium, benzimidazolium, bisbenzimidazolium and quaternary ammonium salts were synthesized, characterized and the inhibition effects of the derivatives on human carbonic anhydrases (hCA I and hCA II) were investigated as in vitro. Structures of these coumarins were confirmed by FT-IR, (1)H NMR, (13)C NMR and LC-MS analyses. Structure activity relationship study showed that 3d (IC50: 79 μM for hCA I and 88 μM for hCA II) performed higher inhibitory activity than others.

  20. Chemical phase analysis of seed mediated synthesized anisotropic silver nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Bharti, Amardeep, E-mail: abharti@pu.ac.in; Goyal, Navdeep [Department of Physics, Panjab University, Chandigarh, INDIA-160014 (India); Singh, Suman; Singla, M. L. [Agrionics, Central Scientific Instruments Organization, CSIR, Chandigarh, INDIA-160030 (India)

    2015-08-28

    Noble-metal nanoparticles are of great interest because of its broad applications almost in every stream (i.e. biology, chemistry and engineering) due to their unique size/shape dependant properties. In this paper, chemical phase of seed mediated synthesized anisotropic silver nanoparticle (AgNPs) has been investigated via fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). These nanaoparticles were synthesized by seed-growth method controlled by urea and dextrose results to highly stable 12-20 nm particle size revealed by zeta potential and transmission electron microscopy (TEM)

  1. Zinc Oxide Nano crystals Synthesized by Quenching Technique

    International Nuclear Information System (INIS)

    Norhayati Abu Bakar; Akrajas Ali Umar; Muhamad Mat Salleh; Muhammad Yahya

    2011-01-01

    This paper reports an attempt to synthesize non toxic zinc oxide (ZnO) nano crystals using a simple quenching technique. The hot zinc oxide powder was quenched in hexane solution to obtain ZnO nano crystals. As the result, diameter size of the synthesized ZnO is 200 nm. It was also exhibited a good crystalline with wurtzite phase. The nano crystals properties of ZnO were revealed from good absorbance and green luminescence under UV exposure. This may be related with oxygen vacancy ionization during the annealing process. (author)

  2. Phase-predictable tuning of single-frequency optical synthesizers.

    Science.gov (United States)

    Rohde, Felix; Benkler, Erik; Puppe, Thomas; Unterreitmayer, Reinhard; Zach, Armin; Telle, Harald R

    2014-07-15

    We investigate the tuning behavior of a novel type of single-frequency optical synthesizers by phase comparison of the output signals of two identical devices. We achieve phase-stable and cycle-slip free frequency tuning over 28.1 GHz with a maximum zero-to-peak phase deviation of 62 mrad. In contrast to previous implementations of single-frequency optical synthesizers, no comb line order switching is needed when tuned over more than one comb line spacing range of the employed frequency comb.

  3. Synthesis and antimicrobial activity of a new series of 1,4-dihydropyridine derivatives

    Directory of Open Access Journals (Sweden)

    RADHAKRISHNAN SURENDRA KUMAR

    2011-01-01

    Full Text Available A series of 1,4-dihydropyridine derivatives (1a–g were prepared from Hantzsch syntheses. The compounds 1a–g were reacted with thiosemicarbazide to give the new series of compounds 2a–g. IR, 1H-NMR, 13C-NMR, mass spectral and elemental analysis confirmed the synthesized compounds. The synthesized compounds were also screened for their antimicrobial activity.

  4. Degree of Branching in Hyperbranched Poly(glycerol-co-diacids Synthesized in Toluene

    Directory of Open Access Journals (Sweden)

    Gary D. Strahan

    2012-02-01

    Full Text Available 1H NMR and 13C NMR spectrometry (1-dimensional and 2-dimensional have been used to assign chemical resonances and determine the degrees of branching for polyesters synthesized by the Lewis acid (dibutyltin(IVoxide-catalyzed polycondensation of glycerol with either succinic acid (n (aliphatic chain length = 2, glutaric acid (n = 3 or azelaic acid (n = 7 in quasi-melt solutions with toluene. When 1:1 and 2:1 (diacid:glycerol molar ratios were used, it was found that the glutaric acid-derived polymers gave the highest degree of polymer branching (31.2%, 85.6%, respectively after the 24 h reaction period followed by the succinic acid-derived polymers (39.4%, 41.9%, respectively and the azelaic acid-derived polymers (9.9%, 13.9%, respectively. Reactions performed at reflux for 24 h resulted in a 70.8% and 56.7% decrease in degree of branching for succinic acid and glutaric acid-derived polyesters, respectively. There is no indication that degree of branching is significantly affected by the presence or absence of solvent according to the results obtained in this research.

  5. Langmuir-Blodgett Films of Graphene Derivatives

    DEFF Research Database (Denmark)

    Petersen, Søren Vermehren

    The work presented in this PhD thesis can be divided into two main categories: 1) Syn-thesis and Langmuir-Blodgett assembly of graphene derivatives and 2) Application and characterization of graphene derivatives as an interface material in molecular electron-ics. While the first category could...... be divided further, the synthesis and Langmuir-Blodgett results are intertwined in such a way that it would be more confusing to pre-sent them separately. The Langmuir-Blodgett deposition also played a crucial, but more isolated, part in the investigation of graphene derivatives as interface material....... Solution processable graphene in the form of chemically derived graphene has been synthesized through the modified Hummers method with subsequent reduction into reduced graphene oxide with hydrazine. The completeness of oxidation, the effect of the refinement steps and the reduction of the graphene oxide...

  6. An efficient conversion of maleimide derivatives to 2-thioxo imidazolidinones.

    Directory of Open Access Journals (Sweden)

    Lydia Salhi

    2013-06-01

    Full Text Available Starting from maleimide derivatives, a series of 2-thioxoimidazolidinones was prepared through two different procedures. These syntheses have achieved in two steps via reaction between maleimide derivatives 1,semicarbazide hydrochloride 9 and isothiocyanates5,the best results being obtained under acid conditions (AcOH or heteropolyacid in ethanol or acétonitrile. The synthesized compounds 11a-f and substituted thiohydantoins 6a-h, 8a-h were screened for their in vitro anti-bacterial activity against four bacterial strains.

  7. Synthesis and biological evaluation of 2-substituted benzimidazole derivatives

    Directory of Open Access Journals (Sweden)

    Gurusamy Mariappan

    2015-09-01

    Full Text Available A novel series of 2-substituted benzimidazole derivatives (3a–3j were synthesized by the reaction of 2-chloro methyl benzimidazole with substituted primary aromatic amines. All the compounds were characterized by UV, IR, 1H NMR, mass spectral data and CHN elemental analysis. The synthesized derivatives were screened for analgesic and anti-inflammatory activities. All the compounds showed significant effect at 100 mg/kg p.o. and the experimental data are statistically significant at p < 0.01 level.

  8. Antibacterial activity of silver nanoparticles synthesized from serine

    Energy Technology Data Exchange (ETDEWEB)

    Jayaprakash, N. [Catalysis and Nanomaterials Research Laboratory, Department of Chemistry, Loyola College, Chennai 600 034 (India); SRM Valliammai Engineering College, Department of Chemistry, Chennai 603 203 (India); Judith Vijaya, J., E-mail: jjvijayaloyola@yahoo.co.in [Catalysis and Nanomaterials Research Laboratory, Department of Chemistry, Loyola College, Chennai 600 034 (India); John Kennedy, L. [Materials Division, School of Advanced Sciences, VIT University, Chennai Campus, Chennai 600 048 (India); Priadharsini, K.; Palani, P. [Department of Center for Advanced Study in Botany, University of Madras, Guindy Campus, Chennai 600 025 (India)

    2015-04-01

    Silver nanoparticles (Ag NPs) were synthesized by a simple microwave irradiation method using polyvinyl pyrrolidone (PVP) as a capping agent and serine as a reducing agent. UV–Visible spectra were used to confirm the formation of Ag NPs by observing the surface plasmon resonance (SPR) band at 443 nm. The emission spectrum of Ag NPs showed an emission band at 484 nm. In the presence of microwave radiation, serine acts as a reducing agent, which was confirmed by Fourier transformed infrared (FT-IR) spectrum. High-resolution transmission electron microscopy (HR-TEM) and high-resolution scanning electron microscopy (HR-SEM) were used to investigate the morphology of the synthesized sample. These images showed the sphere-like morphology. The elemental composition of the sample was determined by the energy dispersive X-ray analysis (EDX). Selected area electron diffraction (SAED) was used to find the crystalline nature of the Ag NPs. The electrochemical behavior of the synthesized Ag NPs was analyzed by the cyclic voltammetry (CV). Antibacterial experiments showed that the prepared Ag NPs showed relatively similar antibacterial activities, when compared with AgNO{sub 3} against Gram-positive and Gram-negative bacteria. - Highlights: • Microwave irradiation method is used to synthesize silver nanoparticles. • Highly stable silver nanoparticles are produced from serine. • A detailed study of antibacterial activities is discussed. • Formation mechanism of silver microspheres has been proposed.

  9. Study of as-synthesized and calcined hydrocalumites as possible ...

    Indian Academy of Sciences (India)

    Administrator

    calcine at different temperatures Ca/Al hydrocalumite- type solids for evaluating their basic properties in vitro as antacid. Results are compared to those obtained with a commercial antacid based on hydrotalcite as active agent. 2. Experimental. 2.1 Synthesis of hydrocalumite (HC). Hydrocalumite was synthesized by the co- ...

  10. Evaluation of Biological Activities of Chemically Synthesized Silver Nanoparticles

    Directory of Open Access Journals (Sweden)

    Ashraf A. Mostafa

    2015-01-01

    Full Text Available Silver nanoparticles were synthesized by the earlier reported methods. The synthesized nanoparticles were characterized using ultraviolet-visible spectrophotometry (UV/Vis, transmission electron microscopy (TEM, energy dispersive X-ray spectroscopy (EDX, and X-ray powder diffraction (XRD. The synthesized materials were also evaluated for their antibacterial activity against Gram positive and Gram negative bacterial strains. TEM micrograph showed the spherical morphology of AgNPs with size range of 40–60 nm. The synthesized nanoparticles showed a strong antimicrobial activity and their effect depends upon bacterial strain as AgNPs exhibited greater inhibition zone for Pseudomonas aeruginosa (19.1 mm followed by Staphylococcus aureus (14.8 mm and S. pyogenes (13.6 mm while the least activity was observed for Salmonella typhi (12.5 mm at concentration of 5 µg/disc. The minimum inhibitory concentration (MIC of AgNPs against S. aureus was 2.5 µg/disc and less than 2.5 µg/disc for P. aeruginosa. These results suggested that AgNPs can be used as an effective antiseptic agent for infectious control in medical field.

  11. Cost effective and shape controlled approach to synthesize ...

    Indian Academy of Sciences (India)

    Cost effective and shape controlled approach to synthesize hierarchically assembled NiO nanoflakes for the removal of toxic heavy metal ions in aqueous solution. K Yogesh Kumar H B Muralidhara Y Arthoba Nayaka H Hanumanthappa M S Veena S R Kiran Kumar. Volume 38 Issue 1 February 2015 pp 271-282 ...

  12. The Challenge of Synthesizing Oligomers for Molecular Wires

    DEFF Research Database (Denmark)

    Søndergaard, Roar; Krebs, Frederik C

    2011-01-01

    molecules with a molecular length up to 9–10 nm which allow for the introduction of aromatic thioacetate functionality in fully conjugated oligomer systems. Oligomers containing 3–15 phenyl units were synthesized by step wise Horner-Wadsworth-Emmons (HWE) reactions of a bifunctional OPV-monomer, which...

  13. Characterization of chemically synthesized CdS nanoparticles

    Indian Academy of Sciences (India)

    Cadmium sulphide is an important semiconductor and has many optoelectronic applications including solar cells, photodiodes, light emitting diodes, nonlinear op- tics and hetergeneous photocatalysis. In the present study we have synthesized. CdS nanoparticles of size ~2.6 nm through chemical precipitation technique.

  14. Bioactive nanocrystalline wollastonite synthesized by sol–gel ...

    Indian Academy of Sciences (India)

    The sol–gel combustion method was employed to synthesize the nanocrystalline wollastonite by taking the raw eggshell powder as a calcium source and TEOS as a source of silicate. Glycine was used as a reductant or fuel and nitrate ions present in metal nitrate acts as an oxidizer. The phase purity of the wollastonite was ...

  15. Synthesizing genetic sequential logic circuit with clock pulse generator.

    Science.gov (United States)

    Chuang, Chia-Hua; Lin, Chun-Liang

    2014-05-28

    Rhythmic clock widely occurs in biological systems which controls several aspects of cell physiology. For the different cell types, it is supplied with various rhythmic frequencies. How to synthesize a specific clock signal is a preliminary but a necessary step to further development of a biological computer in the future. This paper presents a genetic sequential logic circuit with a clock pulse generator based on a synthesized genetic oscillator, which generates a consecutive clock signal whose frequency is an inverse integer multiple to that of the genetic oscillator. An analogous electronic waveform-shaping circuit is constructed by a series of genetic buffers to shape logic high/low levels of an oscillation input in a basic sinusoidal cycle and generate a pulse-width-modulated (PWM) output with various duty cycles. By controlling the threshold level of the genetic buffer, a genetic clock pulse signal with its frequency consistent to the genetic oscillator is synthesized. A synchronous genetic counter circuit based on the topology of the digital sequential logic circuit is triggered by the clock pulse to synthesize the clock signal with an inverse multiple frequency to the genetic oscillator. The function acts like a frequency divider in electronic circuits which plays a key role in the sequential logic circuit with specific operational frequency. A cascaded genetic logic circuit generating clock pulse signals is proposed. Based on analogous implement of digital sequential logic circuits, genetic sequential logic circuits can be constructed by the proposed approach to generate various clock signals from an oscillation signal.

  16. Syntheses, characterization and crystal structures of potassium and ...

    Indian Academy of Sciences (India)

    Syntheses, characterization and crystal structures of potassium and barium complexes of a Schiff base ligand with different anions. Bhavesh Parmar Kamal Kumar Bisht Pratyush Maiti Parimal Paul Eringathodi Suresh. Special issue on Chemical Crystallography Volume 126 Issue 5 September 2014 pp 1373-1384 ...

  17. Antibacterial potential of silver nanoparticle synthesized by marine ...

    African Journals Online (AJOL)

    Multi resistance to antibiotics is a serious and disseminated clinical problem, common to several new compounds that block the resistance mechanism. The present study aimed at the comparative study of silver nanoparticles synthesized through actinomycetes and their antimicrobial metabolites with standard antibiotic.

  18. Study of as-synthesized and calcined hydrocalumites as possible ...

    Indian Academy of Sciences (India)

    Administrator

    Unidad de Síntesis de Materiales y Metales de Transición, Facultad de Ciencias y Tecnología,. Departamento de Química, Universidad de Carabobo, Valencia, Edo. Carabobo, Apartado Postal 3336, Venezuela. MS received 1 April 2013; revised 22 June 2013. Abstract. A hydrocalumite-type solid was synthesized by the ...

  19. ARSENIC REMOVAL USING SOL-GEL SYNTHESIZED TITANIUM DIOXIDE NANOPARTICLES

    Science.gov (United States)

    In this study, the effectiveness of TiO2 nanoparticles in arsenic adsorption was examined. TiO2 particles (LS) were synthesized via sol-gel techniques and characterized for their crystallinity, surface area and pore volume. Batch adsorption studies were perf...

  20. A frequency tracking synthesizer for beam diagnostic systems

    International Nuclear Information System (INIS)

    Peterson, D.; Marriner, J.

    1991-01-01

    In low and medium energy synchrotrons the beam revolution frequency changes by a large factor during the acceleration process. High production rates require that these machines cycle rapidly. In attempting to diagnose instabilities which develop during the acceleration process it is useful to be able to select some frequency segment between revolution harmonics for viewing. Most types of test equipment operating in the frequency domain, such as spectrum analyzers and network analyzers, are not suited to making direct measurements on such rapidly sweeping signals. Ideally, one would want to set the frequency frame of reference to the spot in the accelerating revolution harmonic domain where the measurements are to be made. A scheme using a direct digital synthesizer (DDS) was developed to provide this moving reference frame. This paper describes a synthesizer scheme combining digital and analog synthesizer techniques to allow tracking of signals during acceleration. Virtually any ratio of synthesizer to beam revolution frequency may be generated by this scheme. Details of hardware and measurement results are presented

  1. Evaluation of Biological Activities of Chemically Synthesized Silver Nanoparticles

    International Nuclear Information System (INIS)

    Mostafa, A. A.; Solkamy, E.N.; Sayed, Sh. R. M.; Khan, M.; Shaik, M.R.; Al-Warthan, A.; Adil, S.F.

    2015-01-01

    Silver nanoparticles were synthesized by the earlier reported methods. The synthesized nanoparticles were characterized using ultraviolet-visible spectrophotometry (UV/Vis), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), and X-ray powder diffraction (XRD). The synthesized materials were also evaluated for their antibacterial activity against Gram positive and Gram negative bacterial strains. TEM micrograph showed the spherical morphology of AgNPs with size range of 40-60 nm. The synthesized nanoparticles showed a strong antimicrobial activity and their effect depends upon bacterial strain as AgNPs exhibited greater inhibition zone for Pseudomonas aeruginosa (19.1 mm) followed by Staphylococcus aureus (14.8?mm) and S. pyogenes (13.6 mm) while the least activity was observed for Salmonella typhi (12.5 mm) at concentration of 5 μg/disc. The minimum inhibitory concentration (MIC) of AgNPs against S. aureus was 2.5 μg/disc and less than 2.5 μg/disc for P. aeruginosa. These results suggested that AgNPs can be used as an effective antiseptic agent for infectious control in medical field.

  2. Effect of aging on copper nanoparticles synthesized by pulsed laser ...

    Indian Academy of Sciences (India)

    Administrator

    2009-06-23

    Jun 23, 2009 ... Effect of aging on copper nanoparticles in water. 1365. Figure 1. (a) UV-Visible absorption spectrum of as synthesized colloidal solution of nanoparticles by laser ablation of copper in water, (b) UV-Visible absorption spectra of colloidal nanoparticles recorded with aging of 6 alternate days and (c) Tauc plot ...

  3. group chemistry of 9-hydroxophenalenone: Syntheses and structural ...

    Indian Academy of Sciences (India)

    Sci. Vol. 126, No. 5, September 2014, pp. 1581–1588. c Indian Academy of Sciences. Main group chemistry of 9-hydroxophenalenone: Syntheses and structural characterization of the alkaline earth and zinc complexes. ARUP MUKHERJEEa, PRINSON P SAMUELb, CAROLA SCHULZKEc and. SWADHIN K MANDALa,∗.

  4. Parametric Audio Based Decoder and Music Synthesizer for Mobile Applications

    NARCIS (Netherlands)

    Oomen, A.W.J.; Szczerba, M.Z.; Therssen, D.

    2011-01-01

    This paper reviews parametric audio coders and discusses novel technologies introduced in a low-complexity, low-power consumption audiodecoder and music synthesizer platform developed by the authors. Thedecoder uses parametric coding scheme based on the MPEG-4 Parametric Audio standard. In order to

  5. Sol–gel synthesized mesoporous anatase titanium dioxide ...

    Indian Academy of Sciences (India)

    classification. A hysteresis loop with a stepwise adsorption and desorption branch is observed at wide range of pressure. (P /Po). The BET surface area of TiO2 nanoparticles is. 31.76 m2 g−1 as shown in figure 5a. This result indicates that the synthesized material has wider mesoporous struc- ture. To analyse pore size, the ...

  6. Biogenic ZnO nanoparticles synthesized using L. aculeata leaf

    Indian Academy of Sciences (India)

    ... Refresher Courses · Symposia · Live Streaming. Home; Journals; Bulletin of Materials Science; Volume 39; Issue 1. Biogenic ZnO nanoparticles synthesized using L. aculeata leaf extract and their antifungal activity against plant fungal pathogens. S Narendhran Rajeshwari Sivaraj. Volume 39 Issue 1 February 2016 pp 1- ...

  7. Syntheses, structures and properties of two dinuclear mercury (II ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 126; Issue 3. Syntheses, structures and properties of two dinuclear mercury(II) iodide compounds containing tetradentate tripodal amine/pentadentate N-donor Schiff base: Control of molecular and crystalline architectures by varying ligand matrices. Subhasis Roy ...

  8. Investigation of formation constant of complex of a new synthesized ...

    African Journals Online (AJOL)

    The complex formation between a newly synthesized tripodal ligand and the cation Cu2+ in water and surfactant media was studied spectrophotometrically using rank annihilation factor analysis (RAFA). According to molar ratio data the stoichiometry of complexation between the ligand and the cation Cu2+ was 1:1.

  9. development of a hydrothermal method to synthesize spherical znse

    African Journals Online (AJOL)

    Preferred Customer

    ABSTRACT. Hydrothermal method was used to synthesize pure ZnSe nanosphere materials. The effects of the reducing agent amount, the reaction time and temperature were investigated on the purity of ZnSe. Also, the effects of surfactants such as sodium dodecyl sulfate (SDS) (anionic) and cetyl trimethylammonium ...

  10. Syntheses, characterization, and anti-cancer activities of pyridine ...

    Indian Academy of Sciences (India)

    Syntheses, characterization, and anti-cancer activities of pyridine-amide based compounds containing appended phenol or catechol groups. AFSAR ALIa, DEEPAK BANSALa, NAGENDRA K KAUSHIKb, NEHA KAUSHIKb,. EUN HA CHOIb and RAJEEV GUPTAa,∗. aDepartment of Chemistry, University of Delhi, Delhi 110 ...

  11. Biogenic ZnO nanoparticles synthesized using L. aculeata leaf ...

    Indian Academy of Sciences (India)

    de-ionized water followed by methanol and air dried. This product was annealed at 400◦C for 2 h. At the end, colourless powder was obtained [17]. 2.4 Characterization of ZnO nanoparticles. Optical properties of synthesized ZnO nanoparticles were confirmed by ultraviolet–visible spectroscopy (UV–vis) (UV-. 2450 ...

  12. Syntheses, structures and properties of two coordination polymers of ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Chemical Sciences; Volume 129; Issue 12. Syntheses, structures and properties of two coordination polymers of Cadmium(II) pseudohalide containing an in situ generated bidentate Schiff base: Control of dimensionality by varying pseudohalides. REGULAR ARTICLE Volume 129 Issue 12 ...

  13. Comparative study of synthesized silver and gold nanoparticles ...

    Indian Academy of Sciences (India)

    in vitro anticancer efficacy of synthesized silver and gold nanoparticles using leaves extract of Bauhinia tomen- tosa Linn. ... AuNPs and aqueous extract of leaves confirmed by MTT assay exhibited IC50 concentrations of 28.125, 46.875 and. 50 μg ml ... applications such as the treatment of cancer, gene therapy and drug ...

  14. Nanoscale grain growth behaviour of CoAl intermetallic synthesized ...

    Indian Academy of Sciences (India)

    Grain growth behaviour of the nanocrystalline CoAl intermetallic compound synthesized by mechanical alloying has been studied by isothermal annealing at different temperatures and durations. X-ray diffraction method was employed to investigate structural evolutions during mechanical alloying and annealing processes.

  15. Die Meta-Synthese zur Aggregation und Reflektion qualitativer Fallstudien

    DEFF Research Database (Denmark)

    Gretzinger, Susanne; Leick, Birgit

    2018-01-01

    Metasynthesis, the qualitative counterpart of metaanalysis (Hunt 1997), is defined as “an exploratory, inductive research design to synthesize primary qualitative case studies for the purpose of making contributions beyond those achieved in the original studies” (Hoon 2013: 523, see also Sandelow...

  16. Synthesizing Knowledge on Internet of Things (IoT)

    DEFF Research Database (Denmark)

    Liu, Fei; Tan, Chee-Wee; Lim, Eric T. K.

    2016-01-01

    Research on Internet of Things (IoT) has been booming for past couple of years due to technological advances and its potential for application. Nonetheless, the rapid growth of IoT articles as well as the heterogeneous nature of IoT pose challenges in synthesizing prior research on the phenomenon...

  17. Biomedical applications of green synthesized Nobel metal nanoparticles.

    Science.gov (United States)

    Khan, Zia Ul Haq; Khan, Amjad; Chen, Yongmei; Shah, Noor S; Muhammad, Nawshad; Khan, Arif Ullah; Tahir, Kamran; Khan, Faheem Ullah; Murtaza, Behzad; Hassan, Sadaf Ul; Qaisrani, Saeed Ahmad; Wan, Pingyu

    2017-08-01

    Synthesis of Nobel metal nanoparticles, play a key role in the field of medicine. Plants contain a substantial number of organic constituents, like phenolic compounds and various types of glycosides that help in synthesis of metal nanoparticles. Synthesis of metal nanoparticles by green method is one of the best and environment friendly methods. The major significance of the green synthesis is lack of toxic by-products produced during metal nanoparticle synthesis. The nanoparticles, synthesized by green method show various significant biological activities. Most of the research articles report the synthesized nanoparticles to be active against gram positive and gram negative bacteria. Some of these bacteria include Escherichia coli, Bacillus subtilis, Klebsiella pneumonia and Pseudomonas fluorescens. The synthesized nanoparticles also show significant antifungal activity against Trichophyton simii, Trichophyton mentagrophytes and Trichophyton rubrum as well as different types of cancer cells such as breast cancer cell line. They also exhibit significant antioxidant activity. The activities of these Nobel metal nano-particles mainly depend on the size and shape. The particles of small size with large surface area show good activity in the field of medicine. The synthesized nanoparticles are also active against leishmanial diseases. This research article explores in detail the green synthesis of the nanoparticles and their uses thereof. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Syntheses of Diazadithiacrown Ethers Containing Two 8-Hydroxyquinoline Side Arms

    National Research Council Canada - National Science Library

    Song, H

    2001-01-01

    .... HQ-containing ligands 23-32 were synthesized by a Mannich reaction of the secondary macrocyclic diamines with the substituted-8-hydroxyquinoline. HQ-containing ligands 33-36 were prepared by reductive amination of the secondary macrocyclic diamines with 8-hydroxyquinoline-2-carbaldehyde.

  19. Synthesizing Learning on Adaptation to Climate Change | CRDI ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Synthesizing Learning on Adaptation to Climate Change. Climate Change Adaptation in Africa (CCAA), a program is supported by IDRC and the United Kingdom's Department for International Development (DFID), supports three kinds of activity: research, capacity building and networking. Since 2006, CCAA has supported ...

  20. Synthesis of New Thiazole Derivatives Bearing A Sulfonamide Moiety Of Expected Anticancer And Radiosensitizing Activities

    International Nuclear Information System (INIS)

    Mohamed, S.Sh.I.

    2012-01-01

    In a search for new cytotoxic agents with improved antitumor activity and selectivity, some new pyrano thiazole and thiazolopyranopyrimidine derivatives bearing sulfonamide moiety were synthesized. The newly synthesized compounds were evaluated for their antitumor activity alone and in combination with γ-irradiation. These new compounds were docked inside the active site of carbonic anhydrase II to predict their mechanism of action.

  1. Methods of synthesizing qualitative research studies for health technology assessment.

    Science.gov (United States)

    Ring, Nicola; Jepson, Ruth; Ritchie, Karen

    2011-10-01

    Synthesizing qualitative research is an important means of ensuring the needs, preferences, and experiences of patients are taken into account by service providers and policy makers, but the range of methods available can appear confusing. This study presents the methods for synthesizing qualitative research most used in health research to-date and, specifically those with a potential role in health technology assessment. To identify reviews conducted using the eight main methods for synthesizing qualitative studies, nine electronic databases were searched using key terms including meta-ethnography and synthesis. A summary table groups the identified reviews by their use of the eight methods, highlighting the methods used most generally and specifically in relation to health technology assessment topics. Although there is debate about how best to identify and quality appraise qualitative research for synthesis, 107 reviews were identified using one of the eight main methods. Four methods (meta-ethnography, meta-study, meta-summary, and thematic synthesis) have been most widely used and have a role within health technology assessment. Meta-ethnography is the leading method for synthesizing qualitative health research. Thematic synthesis is also useful for integrating qualitative and quantitative findings. Four other methods (critical interpretive synthesis, grounded theory synthesis, meta-interpretation, and cross-case analysis) have been under-used in health research and their potential in health technology assessments is currently under-developed. Synthesizing individual qualitative studies has becoming increasingly common in recent years. Although this is still an emerging research discipline such an approach is one means of promoting the patient-centeredness of health technology assessments.

  2. On the one pot syntheses of chromeno[4,3-b]pyridine-3-carboxylate and chromeno[3,4-c]pyridine-3-carboxylate and dihydropyridines

    Energy Technology Data Exchange (ETDEWEB)

    Navarrete-Encina, Patricio A.; Vega-Retter, Christian, E-mail: pnavarre@vtr.ne [Universidad de Chile, Santiago (Chile). Facultad de Ciencias Quimicas y Farmaceuticas. Lab. de Sintesis Organica y Fisicoquimica; Salazar, Ricardo; Perez, Karina; Squella, Juan A.; Nunez-Vergara, Luis J. [Universidad de Chile, Santiago (Chile). Fac. de Ciencias Quimicas y Farmaceuticas. Lab. de Bioelectroquimica

    2010-07-01

    Substituted chromenos, dihydropyridines and pyridines have been important in the syntheses of compounds having interesting pharmacological properties. Therefore, we found of interest to synthesize chromenopyridines and chromeno dihydropyridines (i.e., fused chromeno and dihydropyridine or pyridine rings) to further study their biological activity. Here, we propose one-pot syntheses for substituted ethyl-2,4-dimethyl-5-oxo-5H-chromeno[4,3-b]pyridine-3-carboxylates, ethyl-2,4-dimethyl-5-oxo-5H-chromeno[3,4-c]pyridine-3-carboxylates and their respective 1,4-dihydropyridines based on a modified Hantzsch pyridine synthesis using 2-hydroxyaryl aldehydes, with electron withdrawing and electron donating groups on the phenyl ring, as starting reactants. Sixteen compounds were synthesized by the described method and fully characterized. An average yield of 37% was obtained for the different derivatives. (author)

  3. Cytotoxicity study of pyrazole derivatives

    Directory of Open Access Journals (Sweden)

    Nusrat Binta Ahasan

    2007-06-01

    Full Text Available Pyrazolone heterocyclic compound, 3-methyl-1-phenyl-2-pyrazoline-5-one 2(a was synthesized by condensation reaction between ethyl acetoacetate and phenyl hydrazine and was converted into their corresponding heterocyclic derivatives 2(b to 2(f2 . Their cytotoxicity effects were measured by brine shrimp lethality bioassay. Among them the compounds 2(b , 2(f1 , and 2(f2 were highly active according to IC50 values 19.50, 19.50 and 20 ppm respectively. The rest of compounds 2(a , 2(c , 2(d1 , and 2(d2 having IC50 values 38, 33.50, 37.50, 36, 37.50 and 36 ppm in that order, were moderately active.

  4. Cytotoxicity study of pyrazole derivatives

    Directory of Open Access Journals (Sweden)

    Nusrat Binta Ahasan and Md. Rabiul Islam

    2007-12-01

    Full Text Available Pyrazolone heterocyclic compound, 3-methyl-1-phenyl-2-pyrazoline-5-one 2(a was synthesized by condensation reaction between ethyl acetoacetate and phenyl hydrazine and was converted into their corresponding heterocyclic derivatives 2(b to 2(f2. Their cytotoxicity effects were measured by brine shrimp lethality bioassay. Among them the compounds 2(b, 2(f1, and 2(f2 were highly active according to IC50 values 19.50, 19.50 and 20 ppm respectively. The rest of compounds 2(a, 2(c, 2(d1, and 2(d2 having IC50 values 38, 33.50, 37.50, 36, 37.50 and 36 ppm in that order, were moderately active.

  5. synthesis and characterization of some poly functionalized heterocyclic derivatives of expected biological activity

    International Nuclear Information System (INIS)

    El-sayed, M.S.

    2001-01-01

    The present work was aimed and designed to fulfil The following objectives : 1- Continuation of the effort done by our research group in the field of chemistry of pyridinethione derivatives and their biological activities. 2- Synthesis of several new heterocyclic derivatives containing N and/or S using the laboratory available reagents. 3- Establishment of the structures of the newly synthesized heterocyclic compounds by the data of IR, 1 H-NMR, mass spectra in addition to the elemental analysis. 4- Synthesis of some of these heterocyclic derivatives via alternative routs and this used as a tool to confirm the structures of the newly synthesized heterocyclic derivatives. 5- study of the most probable mechanisms leading to the formation of the new heterocyclic derivatives. 6- The antimicrobial activity of some of the newly synthesized heterocyclic derivatives was tested against several types of organisms

  6. I. Application of Organoselenium Chemistry in the Syntheses of Tetrapyrroles. II. Chemistry of Marine Natural Products from Xestospongia sp. and Dysidea herbacea

    OpenAIRE

    Brantley, Sarah E.

    1997-01-01

    Part one of this Dissertation describes development of the o-nitrophenylselenium substituent for vinyl group protection and its application in the syntheses of tetrapyrrole derivatives. These derivatives, 5-meso-methylhemin chloride and 3,8-divinylchlorin-e6 trimethyl ester, should be useful in the investigation of heme catabolism and chlorophyll a biosynthetic mechanisms. Chapter one introduces two biologically important tetrapyrroles, heme and chlorophyll a. The theories of heme br...

  7. The Reaction of Cyanoacetylhydrazine with ω-Bromo(4-methylacetophenone: Synthesis of Heterocyclic Derivatives with Antitumor Activity

    Directory of Open Access Journals (Sweden)

    Rafat M. Mohareb

    2010-05-01

    Full Text Available New approaches for the synthesis of hydrazide-hydrazone derivatives were demonstrated as well as some heterocyclizations of such derivatives to afford 1,3,4-triazine, pyridine and 1,3,4-oxadiazine derivatives. The antitumor evaluation of the newly synthesized products against three cancer cell lines, namely breast adenocarcinoma (MCF-7, non-small cell lung cancer (NCI-H460 and CNS cancer (SF-268 were recorded. Most of the synthesized compounds showed high inhibitory effects.

  8. Synthesis and Biological Activity of Substituted Urea and Thiourea Derivatives Containing 1,2,4-Triazole Moieties

    Science.gov (United States)

    2013-03-19

    Biological Activity of Substituted Urea and Thiourea Derivatives Containing 1,2,4- Triazole Moieties Bedia Kocyigit-Kaymakcioglu 1,*, Ahmet Ozgur Celen...of novel thiourea and urea derivatives containing 1,2,4- triazole moieties were synthesized and evaluated for their antifungal and larvicidal activity... Triazole derivatives 3a–e and 4a–e were synthesized by reacting thiocarbohydrazide with thiourea and urea compounds 1a–e and 2a–e, respectively

  9. Thermal and optical characterization of biologically synthesized ZnS nanoparticles synthesized from an endophytic fungus Aspergillus flavus: A colorimetric probe in metal detection.

    Science.gov (United States)

    Uddandarao, Priyanka; Balakrishnan, Raj Mohan

    2017-03-15

    Nanostructured semiconductor materials are of great importance for several technological applications due to their optical and thermal properties. The design and fabrication of metal sulfide nanoparticles with tunable properties for advanced applications have drawn a great deal of attention in the field of nanotechnology. ZnS is a potential II-IV group material which is used in hetero-junction solar cells, light emitting diodes, optoelectronic devices, electro luminescent devices and photovoltaic cells. Due to their multiple applications, there is a need to elucidate their thermal and optical properties. In the present study, thermal and optical properties of biologically synthesized ZnS nanoparticles are determined in detail with Thermal Gravimetric Analysis (TGA), Derivative Thermogravimetric Analysis (DTG), Differential Scanning Calorimeter (DSC), Diffuse Reflectance Spectroscopy (DRS), Photoluminescence (PL) and Raman spectroscopy. The results reveal that ZnS NPs exhibit a very strong quantum confinement with a significant increase in their optical band gap energy. These biologically synthesized ZnS NPs contain protein residues that can selectively bind with metal ions in aqueous solutions and can exhibit an aggregation-induced color change. This phenomenon is utilized to quantitatively measure the metal concentrations of Cu 2+ and Mn 2+ in this study. Further the stability of nanoparticles for the metal sensing process is accessed by UV-Vis spectrometer, zeta potential and cyclic voltammeter. The selectivity and sensitivity of ZnS NPs indicate its potential use as a sensor for metal detection in the ecosystem. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Fluorescent carbon quantum dots synthesized by chemical vapor deposition: An alternative candidate for electron acceptor in polymer solar cells

    Science.gov (United States)

    Cui, Bo; Yan, Lingpeng; Gu, Huimin; Yang, Yongzhen; Liu, Xuguang; Ma, Chang-Qi; Chen, Yongkang; Jia, Husheng

    2018-01-01

    Excitation-wavelength-dependent blue-greenish fluorescent carbon quantum dots (CQDs) with graphite structure were synthesized by chemical vapor deposition (CVD) method. In comparison with those synthesized by hydrothermal method (named H-CQDs), C-CQDs have less hydrophilic terminal groups, showing good solubility in common organic solvents. Furthermore, these synthesized C-CQDs show a low LUMO energy level (LUMO = -3.84 eV), which is close to that of phenyl-C61-butyric acid methyl ester (PC61BM, LUMO = -4.01 eV), the most widely used electron acceptor in polymer solar cells. Photoluminescence quenching of the poly(3-hexylthiophene-2,5-diyl):C-CQDs blended film (P3HT:C-CQDs) indicated that a photo-induced charge transfer between P3HT and C-CQDs occurs in such a composite film. Bulk heterojunction solar cells using C-CQDs as electron acceptors or doping materials were fabricated and tested. High fill factors were achieved for these C-CQDs based polymer solar cells, demonstrating that CQDs synthesized by CVD could be alternative to the fullerene derivatives for applying in polymer solar cells.

  11. Synthesis, antimicrobial evaluation and QSAR studies of propionic acid derivatives

    Directory of Open Access Journals (Sweden)

    Sanjiv Kumar

    2017-02-01

    Full Text Available A series of Schiff bases (1–17 and esters (18–24 of propionic acid was synthesized in appreciable yield and characterized by physicochemical as well as spectral means. The synthesized compounds were evaluated in vitro for their antimicrobial activity against Gram-positive bacteria Staphylococcus aureus, Bacillus subtilis, Gram negative bacterium Escherichia coli and fungal strains Candida albicans and Aspergillus niger by tube dilution method. Results of antimicrobial screening indicated that besides having good antibacterial activity, the synthesized compounds also displayed appreciable antifungal activity and compound 10 emerged as the most active antifungal agent (pMICca and pMICan = 1.93. The results of QSAR studies demonstrated that antibacterial, antifungal and overall antimicrobial activities of synthesized propionic acid derivatives were governed by the topological parameters, Kier’s alpha first order shape index (κα1 and valence first order molecular connectivity index (1χv.

  12. Strong nonlinear photonic responses from microbiologically synthesized tellurium nanocomposites

    Science.gov (United States)

    Liao, K.-S.; Wang, Jingyuan; Dias, S.; Dewald, J.; Alley, N.J.; Baesman, S.M.; Oremland, R.S.; Blau, W.J.; Curran, S.A.

    2010-01-01

    A new class of nanomaterials, namely microbiologically-formed nanorods composed of elemental tellurium [Te(0)] that forms unusual nanocomposites when combined with poly(m-phenylenevinylene-co-2,5-dioctoxy-phenylenevinylene) (PmPV) is described. These bio-nanocomposites exhibit excellent broadband optical limiting at 532 and 1064 nm. Nonlinear scattering, originating from the laser induced solvent bubbles and microplasmas, is responsible for this nonlinear behavior. The use of bacterially-formed Te(0) when combined with an organic chemical host (e.g., PmPV) is a new green method of nanoparticle syntheses. This opens the possibilities of using unique, biologically synthesized materials to advance future nanoelectronic and nanophotonic applications. ?? 2009 Elsevier B.V. All rights reserved.

  13. Interaction Studies between Newly Synthesized Photosensitive Polymer and Ionic Liquids

    Directory of Open Access Journals (Sweden)

    In Tae Kim

    2015-01-01

    Full Text Available In this information age, different kinds of photosensitive materials have been used in the manufacture of information storage devices. But these photosensitive materials have the bane of low diffraction efficiency. In order to solve this problem, we have synthesized a novel photosensitive polymer from epoxy-based azopolymers (with three types of azochromophores. Furthermore, we have studied the interaction between this newly synthesized azopolymer and ionic liquids (ILs. For this purpose, we have used the ammonium and imidazolium families of ILs, such as diethylammonium dihydrogen phosphate (DEAP, tributylammonium methyl sulfate (TBMS, triethylammonium 4-aminotoluene-3-sulfonic acid (TASA, and 1-methylimidazolium chloride ([Mim]Cl. To investigate the molecular interaction between azopolymer and ILs, we have used the following spectroscopic methods of analysis: UV-visible spectroscopy, photoluminescence (PL spectroscopy, Fourier transformed infrared spectroscopy (FT-IR, and confocal Raman spectroscopy. In this study, we have developed new photosensitive materials by combining polymer with ILs.

  14. Is Ghrelin Synthesized in the Central Nervous System?

    Directory of Open Access Journals (Sweden)

    Agustina Cabral

    2017-03-01

    Full Text Available Ghrelin is an octanoylated peptide that acts via its specific receptor, the growth hormone secretagogue receptor type 1a (GHSR-1a, and regulates a vast variety of physiological functions. It is well established that ghrelin is predominantly synthesized by a distinct population of endocrine cells located within the gastric oxyntic mucosa. In addition, some studies have reported that ghrelin could also be synthesized in some brain regions, such as the hypothalamus. However, evidences of neuronal production of ghrelin have been inconsistent and, as a consequence, it is still as a matter of debate if ghrelin can be centrally produced. Here, we provide a comprehensive review and discussion of the data supporting, or not, the notion that the mammalian central nervous system can synthetize ghrelin. We conclude that no irrefutable and reproducible evidence exists supporting the notion that ghrelin is synthetized, at physiologically relevant levels, in the central nervous system of adult mammals.

  15. Copper nanoparticles synthesized in polymers by ion implantation

    DEFF Research Database (Denmark)

    Popok, Vladimir; Nuzhdin, Vladimir; Valeev, Valerij

    2015-01-01

    Polymethylmethacrylate (PMMA) and polyimide (PI) samples are implanted by 40 keV Cu+ ions with high fluences in order to synthesize copper nanoparticles in shallow polymer layers. The produced metal/polymer nanocomposites are studied using atomic force and scanning electron microscopies as well...... as optical transmission spectroscopy. It is found that copper nanoparticles nucleation and growth are strongly fluence dependent as well as they are affected by the polymer properties, in particular, by radiation stability yielding different nanostructures for the implanted PI and PMMA. Shallow synthesized...... nanoparticles are observed to partly tower above the sample surface due to a side effect of high-fluence irradiation leading to considerable sputtering of polymers. Implantation and particle formation significantly change optical properties of both polymers reducing transmittance in the UV-visible range due...

  16. Spark plasma sintering of hydrothermally synthesized bismuth ferrite

    Directory of Open Access Journals (Sweden)

    Zorica Branković

    2016-12-01

    Full Text Available Bismuth ferrite, BiFeO3 (BFO, powder was synthesized by hydrothermal method from Bi(NO33·5 H2O and Fe(NO33·9 H2O as precursors. The synthesized powder was further sintered using spark plasma sintering (SPS. The sintering conditions were optimized in order to achieve high density, minimal amount of secondary phases and improved ferroelectric and magnetic properties. The optimal structure and properties were achieved after spark plasma sintering at 630 °C for 20 min, under uniaxial pressure of 90 MPa. The composition, microstructure, ferroelectric and magnetic properties of the SPS samples were characterized and compared to those of conventionally sintered ceramics obtained from the same powder. Although the samples sintered using conventional method showed slightly lower amount of secondary phases, the spark plasma sintered samples exhibited favourable microstructure and better ferroelectric properties.

  17. Applications of Magnetosomes Synthesized by Magnetotactic Bacteria in Medicine

    International Nuclear Information System (INIS)

    Alphandéry, Edouard

    2014-01-01

    Magnetotactic bacteria belong to a group of bacteria that synthesize iron oxide nanoparticles covered by biological material that are called magnetosomes. These bacteria use the magnetosomes as a compass to navigate in the direction of the earth’s magnetic field. This compass helps the bacteria to find the optimum conditions for their growth and survival. Here, we review several medical applications of magnetosomes, such as those in magnetic resonance imaging (MRI), magnetic hyperthermia, and drug delivery. Different methods that can be used to prepare the magnetosomes for these applications are described. The toxicity and biodistribution results that have been published are summarized. They show that the magnetosomes can safely be used provided that they are prepared in specific conditions. The advantageous properties of the magnetosomes compared with those of chemically synthesized nanoparticles of similar composition are also highlighted.

  18. Structural and magnetic properties of mechanochemically synthesized nanosized yttrium titanate

    Directory of Open Access Journals (Sweden)

    Barudžija Tanja

    2012-01-01

    Full Text Available Nanosized perovskite YTiO3 with the mean crystallite size of 18 nm was synthesized for the first time by mechanochemical treatment. The mechanochemical solid state reaction between commercial Y2O3 powder and mechanochemically synthesized TiO powder in molar ratio 0.5:1 was completed for 3 h in a high-energy planetary ball mill in argon atmosphere. The heating in vacuum at 1150 °C for 12 h transforms nanosized YTiO3 to a well-crystallized single-phase perovskite YTiO3. Both samples were characterized by X-ray diffraction (XRD and thermogravimetric (TGA/DTA analyses, as well as superconducting quantum interference device magnetometer (SQUID measurements.

  19. Method of synthesizing silica nanofibers using sound waves

    Science.gov (United States)

    Sharma, Jaswinder K.; Datskos, Panos G.

    2015-09-15

    A method for synthesizing silica nanofibers using sound waves is provided. The method includes providing a solution of polyvinyl pyrrolidone, adding sodium citrate and ammonium hydroxide to form a first mixture, adding a silica-based compound to the solution to form a second mixture, and sonicating the second mixture to synthesize a plurality of silica nanofibers having an average cross-sectional diameter of less than 70 nm and having a length on the order of at least several hundred microns. The method can be performed without heating or electrospinning, and instead includes less energy intensive strategies that can be scaled up to an industrial scale. The resulting nanofibers can achieve a decreased mean diameter over conventional fibers. The decreased diameter generally increases the tensile strength of the silica nanofibers, as defects and contaminations decrease with the decreasing diameter.

  20. Method of synthesizing silica nanofibers using sound waves

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Jaswinder K.; Datskos, Panos G.

    2017-08-08

    A method for synthesizing silica nanofibers using sound waves is provided. The method includes providing a solution of polyvinyl pyrrolidone, adding sodium citrate and ammonium hydroxide to form a first mixture, adding a silica-based compound to the solution to form a second mixture, and sonicating the second mixture to synthesize a plurality of silica nanofibers having an average cross-sectional diameter of less than 70 nm and having a length on the order of at least several hundred microns. The method can be performed without heating or electrospinning, and instead includes less energy intensive strategies that can be scaled up to an industrial scale. The resulting nanofibers can achieve a decreased mean diameter over conventional fibers. The decreased diameter generally increases the tensile strength of the silica nanofibers, as defects and contaminations decrease with the decreasing diameter.

  1. Is Ghrelin Synthesized in the Central Nervous System?

    Science.gov (United States)

    Cabral, Agustina; López Soto, Eduardo J; Epelbaum, Jacques; Perelló, Mario

    2017-03-15

    Ghrelin is an octanoylated peptide that acts via its specific receptor, the growth hormone secretagogue receptor type 1a (GHSR-1a), and regulates a vast variety of physiological functions. It is well established that ghrelin is predominantly synthesized by a distinct population of endocrine cells located within the gastric oxyntic mucosa. In addition, some studies have reported that ghrelin could also be synthesized in some brain regions, such as the hypothalamus. However, evidences of neuronal production of ghrelin have been inconsistent and, as a consequence, it is still as a matter of debate if ghrelin can be centrally produced. Here, we provide a comprehensive review and discussion of the data supporting, or not, the notion that the mammalian central nervous system can synthetize ghrelin. We conclude that no irrefutable and reproducible evidence exists supporting the notion that ghrelin is synthetized, at physiologically relevant levels, in the central nervous system of adult mammals.

  2. Activation of catalysts for synthesizing methanol from synthesis gas

    Science.gov (United States)

    Blum, David B.; Gelbein, Abraham P.

    1985-01-01

    A method for activating a methanol synthesis catalyst is disclosed. In this method, the catalyst is slurried in an inert liquid and is activated by a reducing gas stream. The activation step occurs in-situ. That is, it is conducted in the same reactor as is the subsequent step of synthesizing methanol from a methanol gas stream catalyzed by the activated catalyst still dispersed in a slurry.

  3. Design, syntheses, characterization and single crystal X-ray ...

    Indian Academy of Sciences (India)

    Administrator

    Two multicomponent Zn-tetraphenylporphyrin (ZnTPP) based building blocks, have been synthesized for designing microporous crystalline solids. Reactions between ZnTPP and 4,4¢-bipyridine (4,4¢-bpy) in two different molar ratios gave complexes. [{ZnTPP)3{m-4,4¢bpy}2] (1) and [{ZnTPP)2{m-4,4¢-bpy}] (II). Complexes I ...

  4. Annual reports in inorganic and general syntheses 1974

    CERN Document Server

    Niedenzu, Kurt

    1975-01-01

    Annual Reports in Inorganic and General Syntheses-1974 presents an organized annual summary of synthetic developments in inorganic chemistry and its related areas. The book discusses the chemistry of simple and complex metal hydrides of main groups I, II, and III, boron, aluminium, gallium, indium, thallium, silicon, germanium, tin, lead, phosphorus, arsenic, antimony, bismuth, chalcogens, halogens, and pseudohalogens. The text also describes the chemistry of scandium, yttrium, lanthanides, actinides, titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, ma

  5. Improved chemical syntheses of 5,6-dihydro-5-fluorouracil.

    Science.gov (United States)

    LaFrate, Andrew L; Katzenellenbogen, John A

    2007-10-26

    5,6-dihydro-5-fluorouracil (5-DHFU) is a metabolite of the chemotherapy drug 5-fluorouracil (5-FU) of importance for biological studies. 5-DHFU has been prepared by enzymatic reduction of 5-FU and in very low yield by hydrogenation of 5-FU; however, a practical chemical synthesis is not available. Facile racemic syntheses of 5-DHFU from 5-FU or uracil, using p-methoxybenzyl protecting groups followed by L-Selectride reduction, are reported.

  6. Economical parallel oligonucleotide and peptide synthesizer - PET OLIGATOR

    Czech Academy of Sciences Publication Activity Database

    Lebl, M.; Pistek, Ch.; Hachmann, J.; Mudra, Petr; Pešek, Václav; Pokorný, Vít; Poncar, Pavel; Ženíšek, Karel

    2007-01-01

    Roč. 13, 1/2 (2007), s. 367-375 ISSN 1573-3149 Grant - others:NIH SBIR(US) R43 GM61511-01; NIH SBIR(US) R43 GM58981-01 Institutional research plan: CEZ:AV0Z40550506 Keywords : automated synthesizer * centrifugation * parallel synthesis Subject RIV: CC - Organic Chemistry Impact factor: 0.971, year: 2007

  7. Annual reports in inorganic and general syntheses 1972

    CERN Document Server

    Niedenzu, Kurt

    1973-01-01

    Annual Reports in Inorganic and General Syntheses-1972 presents an organized annual summary of synthetic developments in inorganic chemistry and its related areas. The book discusses alkali and alkaline earth elements, alloys, silver, gold, zinc, cadmium, mercury, boron, aluminum, gallium, indium, thallium, yttrium, scandium, lanthanides, actinides, titanium, zirconium, hafnium, Group V and VI transition elements, manganese, technetium, rhenium, iron, cobalt, nickel, ruthenium, osmium, rhodium, and iridium. The text also describes the chemistry of palladium, platinum, silicon, germanium, tin,

  8. Total syntheses of Prelactone V and Prelactone B.

    Science.gov (United States)

    Raghavendra, S; Tadiparthi, Krishnaji; Yadav, J S

    2017-04-10

    The total syntheses of natural products Prelactone-V and Prelactone-B have been accomplished by a novel Chiron approach starting from d-glucose. The synthesis involves isopropylidene acetal formation of d-glucose using Poly(4-vinylpyridine) supported iodine as a catalyst, Tebbe olefination, Grignard reaction, Wittig olefination, selective mono deprotection of acetal using PMA/SiO 2 , hydrogenation and anti-1,3-diol formation are as key steps. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Tailored super magnetic nanoparticles synthesized via template free hydrothermal technique

    Science.gov (United States)

    Attallah, Olivia A.; Girgis, E.; Abdel-Mottaleb, Mohamed M. S. A.

    2016-01-01

    Magnetite nanoparticles of controlled shape and dimensions were synthesized using a modified hydrothermal technique. The influence of different synthesis conditions on the shape, size (length and diameter), structure and magnetic properties of the prepared nanoparticles is presented. The mineral phases, the morphologies, size distribution of the resulting magnetic nanoparticles and their magnetic properties were characterized using different characterization methods. We designed magnetite nanoparticles with different morphologies (nanospheres, nanorods, nanocubes and hexagons) and with improved saturation magnetization reaching 90 emu/g.

  10. Effect of zinc oxide nanoparticles synthesized by a precipitation ...

    Indian Academy of Sciences (India)

    pH.9,10 The synthesis of ZnO nanoparticles by the pre- cipitation method involves the reaction of zinc salts such as Zn(NO3)2, Zn(CH3COO)2·2H2O and ZnSO4 with basic. ∗. Author for correspondence (rudeerat_p@hotmail.com) solutions containing LiOH, NH4OH and NaOH.3,11,12. Kumar et al13 synthesized ZnO ...

  11. Annual reports in inorganic and general syntheses 1973

    CERN Document Server

    Niedenzu, Kurt

    1974-01-01

    Annual Reports in Inorganic and General Syntheses-1973 presents an organized annual summary of synthetic developments in inorganic chemistry and its related areas. The book covers the synthetic aspects and structural or mechanistic features of elements, including the main group hydrides, alkali and alkaline earth elements, boron, aluminium, gallium, indium, thallium, silicon, germanium, tin, and lead, nitrogen, phosphorus, arsenic, antimony, bismuth, chalcogens, halogens and pseudohalogens, and noble gases. The text also discusses the synthetic aspects and structural or mechanistic features of

  12. Analysis of Periodic Errors for Synthesized-Reference-Wave Holography

    Directory of Open Access Journals (Sweden)

    V. Schejbal

    2009-12-01

    Full Text Available Synthesized-reference-wave holographic techniques offer relatively simple and cost-effective measurement of antenna radiation characteristics and reconstruction of complex aperture fields using near-field intensity-pattern measurement. These methods allow utilization of advantages of methods for probe compensations for amplitude and phasing near-field measurements for the planar and cylindrical scanning including accuracy analyses. The paper analyzes periodic errors, which can be created during scanning, using both theoretical results and numerical simulations.

  13. Ubiquitination of Newly Synthesized Proteins at the Ribosome

    OpenAIRE

    Wang, Feng; Canadeo, Larissa A.; Huibregtse, Jon M.

    2015-01-01

    Newly synthesized proteins can be misfolded or damaged because of errors during synthesis or environmental insults (e.g., heat shock), placing a significant burden on protein quality control systems. In addition, numerous human diseases are associated with a deficiency in eliminating aberrant proteins or accumulation of aggregated proteins. Understanding the mechanisms of protein quality control and disposal pathways for misfolded proteins is therefore crucial for therapeutic intervention in ...

  14. Mito-methyl coumarin, a novel mitochondria-targeted drug with great antitumor potential was synthesized.

    Science.gov (United States)

    Wang, Huanan; Xu, Wenqing

    2017-07-15

    Due to higher transmembrane potential of tumor cells, enhanced accumulation of cationic drugs in tumor mitochondria has been attributed to a higher (more negative inside) mitochondrial transmembrane potential compared with normal cells, emerging researchers are focus on developing mitochondria-targeted antitumor drugs. Coumarins showed great potential on antitumor, but mitochondria-targeted coumarin derivatives have not been reported. In the present study, we synthesized mitochondria-targeted-methyl coumarin (mito-methyl coumarin) through coupling 6-methyl coumarin to TPP. We confirmed that mito-methyl coumarin inhibited HeLa cells proliferation selectively, induced ROS generation, reduced mitochondrial membrane potential, promoted mitochondria Ca 2+ accumulation, decreased mitochondria mass and induced HeLa cells apoptosis, but methyl coumarin did not. These results demonstrate that we succeed in synthesizing a novel mitochondria-targeted drug, mito-methyl coumarin, which is effective in inhibiting HeLa cells proliferation and inducing HeLa cells apoptosis through promoting ROS generation and mitochondria Ca 2+ accumulation. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. In vitro cytotoxicity of carbon black nanoparticles synthesized from solution plasma on human lung fibroblast cells

    Science.gov (United States)

    Panomsuwan, Gasidit; Chokradjaroen, Chayanaphat; Rujiravanit, Ratana; Ueno, Tomonaga; Saito, Nagahiro

    2018-01-01

    Carbon black nanoparticles (CB-NPs) have been synthesized from liquid benzene by a solution plasma method at room temperature and atmospheric pressure. The morphological observation by scanning electron microscopy revealed the agglomeration of aggregated fine particles. The synthesized CB-NPs were predominantly amorphous as confirmed by X-ray diffraction. The in vitro cytotoxicity of CB-NPs on the human lung fibroblast (MRC-5) cell line was assessed by the 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and systematically compared with those of two types of commercial carbon blacks (i.e., Vulcan XC-72 and Ketjenblack EC-600JD). Cell viabilities were studied at different concentrations of 32.5, 65, 125, and 250 µg/mL. It was found that the CB-NPs derived from solution plasma exhibited a lower cytotoxicity on the MRC-5 cells than the other two comparative carbon blacks. The viability of MRC-5 cells exposed to CB-NPs remained higher than 90% even at a high concentration of 250 µg/mL. This result preliminarily confirmed the biosafety and potential use of CB-NPs in the field of biological applications.

  16. A Novel Synthesizing Genetic Logic Circuit: Frequency Multiplier.

    Science.gov (United States)

    Chuang, Chia-Hua; Lin, Chun-Liang

    2014-01-01

    This paper presents a novel synthesizing genetic logic circuit design based on an existing synthetic genetic oscillator, which provides a function of frequency multiplier to synthesize a clock signal whose frequency is a multiple of that of the genetic oscillator. In the renowned literature, the synthetic genetic oscillator, known as a repressilator, has been successfully built in Escherichia coli to generate a periodic oscillating phenomenon through three repressive genes repress each other in a chain. On the basis of this fact, our proposed genetic frequency multiplier circuit utilizes genetic Buffers in series with a waveform-shaping circuit to reshape the genetic oscillation signal into a crisp logic clock signal. By regulating different threshold levels in the Buffer, the time length of logic high/low levels in a fundamental sinusoidal wave can be engineered to pulse-width-modulated (PWM) signals with various duty cycles. Integrating some of genetic logic XOR gates and PWM signals from the output of the Buffers, a genetic frequency multiplier circuit can be created and the clock signal with the integer-fold of frequency of the genetic oscillator is generated. The synthesized signal can be used in triggering the downstream digital genetic logic circuits. Simulation results show the applicability of the proposed idea.

  17. Knowledge Syntheses in Medical Education: Demystifying Scoping Reviews.

    Science.gov (United States)

    Thomas, Aliki; Lubarsky, Stuart; Durning, Steven J; Young, Meredith E

    2017-02-01

    An unprecedented rise in health professions education (HPE) research has led to increasing attention and interest in knowledge syntheses. There are many different types of knowledge syntheses in common use, including systematic reviews, meta-ethnography, rapid reviews, narrative reviews, and realist reviews. In this Perspective, the authors examine the nature, purpose, value, and appropriate use of one particular method: scoping reviews. Scoping reviews are iterative and flexible and can serve multiple main purposes: to examine the extent, range, and nature of research activity in a given field; to determine the value and appropriateness of undertaking a full systematic review; to summarize and disseminate research findings; and to identify research gaps in the existing literature. Despite the advantages of this methodology, there are concerns that it is a less rigorous and defensible means to synthesize HPE literature. Drawing from published research and from their collective experience with this methodology, the authors present a brief description of scoping reviews, explore the advantages and disadvantages of scoping reviews in the context of HPE, and offer lessons learned and suggestions for colleagues who are considering conducting scoping reviews. Examples of published scoping reviews are provided to illustrate the steps involved in the methodology.

  18. Radiolytic Syntheses of Nanoparticles and Inorganic-Polymer Hybrid Microgels

    International Nuclear Information System (INIS)

    Chen, Q.; Shi, J.; Zhao, R.; Shen, X.

    2010-01-01

    In the second year of the project, we have gotten progress mainly in two directions. Firstly, for the first time, Prussian blue (PB) nanoparticles (NPs) were successfully synthesized by the partly radiolytic reduction of Fe3+ and Fe(CN)63 in the presence of poly(N-vinyl pyrrolidine) (PVP) under N2 atmospheres at room temperature. With the increase of the concentration of PVP, the size and the size distribution of the synthesized quasi-spherical PB NPs decreased obviously, leading to a hypsochromic shift on their peak position of the characteristic absorption. In the experiment, we further found that the smaller ones have a larger capacity to Cs+, suggesting that the application of PB NPs in curing thallotoxicosis may decrease the usage of PB for the patient to great extent. Secondly, through a series of preliminary experiments, we got a clear picture about the one-step radiolytic preparation of inorganic-poly(methacrylic acid-co-methyl methacrylate) hybrid microgels by surfactant-free emulsion polymerization. Besides, unpurified N-carbamothioylmethacrylamide was synthesized via the methacrylation of thiourea. These created favorable conditions for the one-step synthesis of metal sulfide-poly(methacrylic acid-co-methyl methacrylate) hybrid microgels by -irradiation and surfactant-free emulsion polymerization. (author)

  19. A new approach to synthesize supported ruthenium phosphides for hydrodesulfurization

    International Nuclear Information System (INIS)

    Wang, Qingfang; Wang, Zhiqiang; Yin, Xiaoqian; Zhou, Linxi; Zhang, Minghui

    2016-01-01

    Highlights: • We bring out a new method to synthesize noble metal phosphides at low temperature. • Both RuP and Ru 2 P were synthesized using triphenylphosphine as phosphorus sources. • Ru 2 P was the better active phase for HDS than RuP and metal Ru. • RuP/SiO 2 prepared by new method had better HDS activity to that by TPR method. - Abstract: Supported noble metal ruthenium phosphides were synthesized by one-step H 2 -thermal treatment method using triphenylphosphine (TPP) as phosphorus sources at low temperatures. Two phosphides RuP and Ru 2 P can be prepared by this method via varying the molar ratio of metal salt and TPP. The as-prepared phosphides were characterized by X-ray powder diffraction (XRD), low-temperature N 2 adsorption, CO chemisorption and transmission electronic microscopy (TEM). The supported ruthenium phosphides prepared by new method and conventional method together with contradistinctive metallic ruthenium were evaluated in hydrodesulfurization (HDS) of dibenzothiophene (DBT). The catalytic results showed that metal-rich Ru 2 P was the better active phase for HDS than RuP and metal Ru. Besides this, ruthenium phosphide catalyst prepared by new method exhibited superior HDS activity to that prepared by conventional method.

  20. A new approach to synthesize supported ruthenium phosphides for hydrodesulfurization

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Qingfang [Tianjin Key Laboratory of Water Environment and Resources, Tianjin Normal University, Tianjin 300387 (China); Key Laboratory of Advanced Energy Materials Chemistry (MOE), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), College of Chemistry, Nankai University, Tianjin 300071 (China); Wang, Zhiqiang [Tianjin Key Laboratory of Water Environment and Resources, Tianjin Normal University, Tianjin 300387 (China); Yin, Xiaoqian; Zhou, Linxi [Key Laboratory of Advanced Energy Materials Chemistry (MOE), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), College of Chemistry, Nankai University, Tianjin 300071 (China); Zhang, Minghui, E-mail: zhangmh@nankai.edu.cn [Key Laboratory of Advanced Energy Materials Chemistry (MOE), Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), College of Chemistry, Nankai University, Tianjin 300071 (China); College of Chemistry and Environmental Science, Kashgar University, Kashgar 844006 (China)

    2016-02-15

    Highlights: • We bring out a new method to synthesize noble metal phosphides at low temperature. • Both RuP and Ru{sub 2}P were synthesized using triphenylphosphine as phosphorus sources. • Ru{sub 2}P was the better active phase for HDS than RuP and metal Ru. • RuP/SiO{sub 2} prepared by new method had better HDS activity to that by TPR method. - Abstract: Supported noble metal ruthenium phosphides were synthesized by one-step H{sub 2}-thermal treatment method using triphenylphosphine (TPP) as phosphorus sources at low temperatures. Two phosphides RuP and Ru{sub 2}P can be prepared by this method via varying the molar ratio of metal salt and TPP. The as-prepared phosphides were characterized by X-ray powder diffraction (XRD), low-temperature N{sub 2} adsorption, CO chemisorption and transmission electronic microscopy (TEM). The supported ruthenium phosphides prepared by new method and conventional method together with contradistinctive metallic ruthenium were evaluated in hydrodesulfurization (HDS) of dibenzothiophene (DBT). The catalytic results showed that metal-rich Ru{sub 2}P was the better active phase for HDS than RuP and metal Ru. Besides this, ruthenium phosphide catalyst prepared by new method exhibited superior HDS activity to that prepared by conventional method.

  1. Novel optical password security technique based on optical fractal synthesizer

    Science.gov (United States)

    Wu, Kenan; Hu, Jiasheng; Wu, Xu

    2009-06-01

    A novel optical security technique for safeguarding user passwords based on an optical fractal synthesizer is proposed. A validating experiment has been carried out. In the proposed technique, a user password is protected by being converted to a fractal image. When a user sets up a new password, the password is transformed into a fractal pattern, and the fractal pattern is stored in authority. If the user is online-validated, his or her password is converted to a fractal pattern again to compare with the previous stored fractal pattern. The converting process is called the fractal encoding procedure, which consists of two steps. First, the password is nonlinearly transformed to get the parameters for the optical fractal synthesizer. Then the optical fractal synthesizer is operated to generate the output fractal image. The experimental result proves the validity of our method. The proposed technique bridges the gap between digital security systems and optical security systems and has many advantages, such as high security level, convenience, flexibility, hyper extensibility, etc. This provides an interesting optical security technique for the protection of digital passwords.

  2. Characterization of Chemically Synthesized Polyaniline-Polyvinylchloride-Montmorillonite Nanocomposite

    Directory of Open Access Journals (Sweden)

    Arefeh Tabatabaei

    2015-06-01

    Full Text Available Polyaniline-montmorillonite (PANI-MMT nanocomposite was synthesized by chemical polymerization of aniline in the presence of montmorillonite (MMT nanostructures. The triple hybrid of polyaniline-polyvinylchloridemontmorillonite (PANI-PVC-MMT was prepared by mixing of the synthesized PANIMMT nanocomposite with a solution of polyvinylchloride (PVC in tetrahydrofurane (THF. In addition, PANI-PVC composite was prepared by mixing of pure synthesized PANI and PVC solution in THF. To investigate the mechanical properties, the PANIPVC composite and PANI- PVC-MMT nanocomposite films were prepared with 5, 10 and 15 wt% of pure PANI and PANI-MMT  nanocomposite, respectively. The results showed that the PANI- PVC-MMT nanocomposite film having 10 wt% of PANIMMT nanocomposite displayed the best mechanical properties. Therefore, it was chosen as optimum film and its physico-chemical properties were characterized. The cyclic voltammetry (CV technique confirmed that the triple hybrid of PANI-PVCMMT nanocomposite was electroactive. Also, Fourier transform infrared (FTIR spectroscopy and scanning electron microscopy (SEM techniques were used to characterize the composition and structure of the PANI-PVC-MMT triple hybrid nanocomposite. X- Ray diffraction (XRD technique showed an intercalated structure for the PANI-PVC-MMT nanocomposite. The thermal stability improvement of the PANI-PVC-MMT nanocomposite in comparison with the pure PVC was established by thermogravimetric analysis (TGA.

  3. Antibacterial properties of silver nanoparticles synthesized by marine Ochrobactrum sp.

    Science.gov (United States)

    Thomas, Roshmi; Janardhanan, Anju; Varghese, Rintu T; Soniya, E V; Mathew, Jyothis; Radhakrishnan, E K

    2014-01-01

    Metal nanoparticle synthesis is an interesting area in nanotechnology due to their remarkable optical, magnetic, electrical, catalytic and biomedical properties, but there needs to develop clean, non-toxic and environmental friendly methods for the synthesis and assembly of nanoparticles. Biological agents in the form of microbes have emerged up as efficient candidates for nanoparticle synthesis due to their extreme versatility to synthesize diverse nanoparticles with varying size and shape. In the present study, an eco favorable method for the biosynthesis of silver nanoparticles using marine bacterial isolate has been attempted. Very interestingly, molecular identification proved it as a strain of Ochrobactrum anhtropi. In addition, the isolate was found to have the potential to form silver nanoparticles intracellularly at room temperature within 24 h. The biosynthesized silver nanoparticles were characterized by UV-Vis spectroscopy, transmission electron microscope (TEM) and scanning electron microscope (SEM). The UV-visible spectrum of the aqueous medium containing silver nanoparticles showed a peak at 450 nm corresponding to the plasmon absorbance of silver nanoparticles. The SEM and TEM micrographs revealed that the synthesized silver nanoparticles were spherical in shape with a size range from 38 nm - 85 nm. The silver nanoparticles synthesized by the isolate were also used to explore its antibacterial potential against pathogens like Salmonella Typhi, Salmonella Paratyphi, Vibrio cholerae and Staphylococcus aureus.

  4. Antibacterial properties of silver nanoparticles synthesized by marine Ochrobactrum sp.

    Directory of Open Access Journals (Sweden)

    Roshmi Thomas

    2014-12-01

    Full Text Available Metal nanoparticle synthesis is an interesting area in nanotechnology due to their remarkable optical, magnetic, electrical, catalytic and biomedical properties, but there needs to develop clean, non-toxic and environmental friendly methods for the synthesis and assembly of nanoparticles. Biological agents in the form of microbes have emerged up as efficient candidates for nanoparticle synthesis due to their extreme versatility to synthesize diverse nanoparticles with varying size and shape. In the present study, an eco favorable method for the biosynthesis of silver nanoparticles using marine bacterial isolate has been attempted. Very interestingly, molecular identification proved it as a strain of Ochrobactrum anhtropi. In addition, the isolate was found to have the potential to form silver nanoparticles intracellularly at room temperature within 24 h. The biosynthesized silver nanoparticles were characterized by UV-Vis spectroscopy, transmission electron microscope (TEM and scanning electron microscope (SEM. The UV-visible spectrum of the aqueous medium containing silver nanoparticles showed a peak at 450 nm corresponding to the plasmon absorbance of silver nanoparticles. The SEM and TEM micrographs revealed that the synthesized silver nanoparticles were spherical in shape with a size range from 38 nm - 85 nm. The silver nanoparticles synthesized by the isolate were also used to explore its antibacterial potential against pathogens like Salmonella Typhi, Salmonella Paratyphi, Vibrio cholerae and Staphylococcus aureus.

  5. SYNTHESIS AND ANTIMICROBIAL EVALUATION OF 4-THIAZOLIDINONE DERIVATIVES

    OpenAIRE

    Vijay Vinay; Mudgal Shikha; Bhargava Anurag; Pathak Ashish; Gupta Mukesh

    2011-01-01

    To investigate the activity profile of thiazolidinone derivatives bearing different substituent at 2, 3 and 5 position new thiazolidinone have been prepared by the reaction of Hydrazide hydrazones obtained from the condensation reaction of hydrazides and aldehydes with thioglycolic acid in DMF as solvent. A series of 5-arylidene derivatives of 4-Thiazolidinone have been synthesized and tested for antibacterial and antifungal activity. In antibacterial activity ciprofloxacin while for antifung...

  6. Synthesis and Antibacterial Activities of New Metronidazole and Imidazole Derivatives

    Directory of Open Access Journals (Sweden)

    Abdul Jabar Kh. Atia

    2009-07-01

    Full Text Available New imidazole ring derivatives comprising 1,3-oxazoline, Schiff's bases, thiadiazole, oxadiazole and 1,2,4-triazole moieties are reported. 3-Aminobiimidazol-4-one compounds 7a-c were synthesized by the reaction of compounds 6a-c with hydrazine hydrate. Biimidazole esters 9a-c were converted into biimidazole hydrazide esters 10a-c. Compounds 7a-c and 10a-c were converted into a variety of derivatives.

  7. Antibactericidal effect of some substituted-1, 2, 4-triazole derivatives

    International Nuclear Information System (INIS)

    Singh, R.J.

    2011-01-01

    The syntheses of a series of some substituted-1, 2, 4-triazole derivatives are described. The reaction of sodium salt of a-sulphonated of stearic acid hydrazide (1) with carbon disulphide in alcoholic KOH yielded the corresponding sodium 1-(4-amino-5-mercapto-4H-[1, 2, 4]-triazol-3yl)-heptadecane-1-sulfonate (2). The reaction of compound (2) with urea, chloroacetyl chloride, chloroacetaldehyde and phenacyl bromides yielded the substituted 1, 2, 4-triazole derivatives (3), (4), (5) and (6) respectively. All the synthesized compounds were characterized by IR, PMR, Mass spectral data and elemental analyses. All newly synthesized compounds have been assayed for their antibacterial activities against S. aureus, E. coli, B. subtilis and P. aeruginosa. (author)

  8. Thienoacene-fused pentalenes: Syntheses, structures, physical properties and applications for organic field-effect transistors

    KAUST Repository

    Dai, Gaole

    2014-11-27

    Three soluble and stable thienoacene-fused pentalene derivatives (1-3) with different π-conjugation lengths were synthesized. X-ray crystallographic analysis and density functional theory (DFT) calculations revealed their unique geometric and electronic structures due to the interaction between the aromatic thienoacene units and antiaromatic pentalene moiety. As a result, they all possess a small energy gap and show amphoteric redox behaviour. Time dependent (TD) DFT calculations were used to explain their unique electronic absorption spectra. These new compounds exhibited good thermal stability and ordered packing in solid state and thus their applications in organic field-effect transistors (OFETs) were also investigated. The highest field-effect hole mobility of 0.016, 0.036 and 0.001 cm2 V-1 s-1 was achieved for solution-processed thin films of 1-3, respectively.

  9. Electrochemical Study on Newly Synthesized Chlorocurcumin as an Inhibitor for Mild Steel Corrosion in Hydrochloric Acid

    Directory of Open Access Journals (Sweden)

    Ahmed A. Al-Amiery

    2013-11-01

    Full Text Available A new curcumin derivative, i.e., (1E,4Z,6E-5-chloro-1,7-bis(4-hydroxy-3-methoxyphenylhepta-1,4,6-trien-3-one (chlorocurcumin, was prepared starting with the natural compound curcumin. The newly synthesized compound was characterized by elemental analysis and spectral studies (IR, 1H-NMR and 13C-NMR. The corrosion inhibition of mild steel in 1 M HCl by chlorocurcumin has been studied using potentiodynamic polarization (PDP measurements and electrochemical impedance spectroscopy (EIS. The inhibition efficiency increases with the concentration of the inhibitor but decreases with increases in temperature. The potentiodynamic polarization reveals that chlorocurcumin is a mixed-type inhibitor. The kinetic parameters for mild steel corrosion were determined and discussed.

  10. Syntheses, Structures, and Magnetic Properties of Nickel-Doped Lepidocrocite Titanates

    DEFF Research Database (Denmark)

    Gao, Tao; Norby, Poul; Okamoto, Hiroshi

    2009-01-01

    Ni-doped titanate CsxTi2−x/2Nix/2O4 and its protonic derivative HxTi2−x/2Nix/2O4·xH2O (x = 0.7) were synthesized and characterized by means of synchrotron X-ray diffraction, Raman scattering, X-ray photoelectron spectroscopy (XPS), and magnetic measurements. CsxTi2−x/2Nix/2O4 crystallizes......H2O. Ni- and Mg-codoped titanates CsxTi2−x/2(NiyMg1−y)x/2O4 (x = 0.7, 0 ≤ y ≤ 1) were also reported. The crystal structure, interlayer chemistry, and magnetic properties of the titanates depend on the Ni substitution levels, indicating opportunities for tuning of the properties by controlling...

  11. Palladium-Copper Catalyzed Alkyne Activation as an Entry to Multicomponent Syntheses of Heterocycles

    Science.gov (United States)

    Müller, Thomas J. J.

    Alkynones and chalcones are of paramount importance in heterocyclic chemistry as three-carbon building blocks. In a very efficient manner, they can be easily generated by palladium-copper catalyzed reactions: ynones are formed from acid chlorides and terminal alkynes, and chalcones are synthesized in the sense of a coupling-isomerization (CI) sequence from (hetero)aryl halides and propargyl alcohols. Mild reaction conditions now open entries to sequential and consecutive transformations to heterocycles, such as furans, 3-halo furans, pyrroles, pyrazoles, substituted and annelated pyridines, annelated thiopyranones, pyridimines, meridianins, benzoheteroazepines and tetrahydro-β-carbolines, by consecutive coupling-cyclocondensation or CI-cyclocondensation sequences, as new diversity oriented routes to heterocycles. Domino reactions based upon the coupling-isomerization reaction (CIR) have been probed in the synthesis of antiparasital 2-substituted quinoline derivatives and highly luminescent spiro-benzofuranones and spiro-indolones.

  12. Synthesis of azido derivatives of mucobromic acid

    Directory of Open Access Journals (Sweden)

    N. Mbebe

    2013-04-01

    Full Text Available Mucobromic acid is a highly reactive multicentered molecule. It was converted to its corresponding but unstable diazido derivative by reaction with two equivalents of sodium azide. The resultant 3,4-diazido-5-hydroxyfuran-2(5H-one was obtained in moderate yield (42% but decomposed readily even at low temperatures. Its more stable analogue 3,4-diazido-5-methoxyfuran-2(5H-one was obtained in excellent yield after reacting 5-methoxy-3,4-dibromofuranone with two equivalents of sodium azide. The 4,5-dibromopyridazinones which are in effect masked mucobromic acid derivatives, underwent nucleophilic substitution reactions with various nucleophiles, including azides and afforded corresponding azidopyridazinones in good yields. The synthesized azido-furanone and pyridazinone derivatives are earmarked for click reactions.DOI: http://dx.doi.org/10.4314/bcse.v27i1.17

  13. Langmuir-Blodgett Films of Graphene Derivatives

    DEFF Research Database (Denmark)

    Petersen, Søren Vermehren

    The work presented in this PhD thesis can be divided into two main categories: 1) Syn-thesis and Langmuir-Blodgett assembly of graphene derivatives and 2) Application and characterization of graphene derivatives as an interface material in molecular electron-ics. While the first category could....... Solution processable graphene in the form of chemically derived graphene has been synthesized through the modified Hummers method with subsequent reduction into reduced graphene oxide with hydrazine. The completeness of oxidation, the effect of the refinement steps and the reduction of the graphene oxide...... immobilization of the monolayered graphene oxide via the Langmuir-Blodgett deposition technique prior to a three step reduction scheme involving hydrazine reduc-tion, sulfuric acid de-oxygenation, and thermal annealing. This method resulted in wrin-kle-free reduced graphene oxide with a negligible oxygen content...

  14. Cytotoxic anthranilic acid derivatives from deep sea sediment-derived fungus Penicillium paneum SD-44.

    Science.gov (United States)

    Li, Chun-Shun; Li, Xiao-Ming; Gao, Shu-Shan; Lu, Yan-Hua; Wang, Bin-Gui

    2013-08-21

    Five new anthranilic acid derivatives, penipacids A-E (1-5), together with one known analogue (6), which was previously synthesized, were characterized from the ethyl acetate extract of the marine sediment-derived fungus Penicillium paneum SD-44. Their structures were elucidated mainly by extensive NMR spectroscopic and mass spectrometric analysis. The cytotoxicity and antimicrobial activity of the isolated compounds were evaluated. Compounds 1, and 5 exhibited inhibitory activity against human colon cancer RKO cell line, while compound 6 displayed cytotoxic activity against Hela cell line.

  15. Cytotoxic Anthranilic Acid Derivatives from Deep Sea Sediment-Derived Fungus Penicillium paneum SD-44

    Directory of Open Access Journals (Sweden)

    Bin-Gui Wang

    2013-08-01

    Full Text Available Five new anthranilic acid derivatives, penipacids A–E (1–5, together with one known analogue (6, which was previously synthesized, were characterized from the ethyl acetate extract of the marine sediment-derived fungus Penicillium paneum SD-44. Their structures were elucidated mainly by extensive NMR spectroscopic and mass spectrometric analysis. The cytotoxicity and antimicrobial activity of the isolated compounds were evaluated. Compounds 1, and 5 exhibited inhibitory activity against human colon cancer RKO cell line, while compound 6 displayed cytotoxic activity against Hela cell line.

  16. In vitro Activity and Safety Assessment of New Synthesized Thiazolo ...

    African Journals Online (AJOL)

    Purpose: To synthesis a series of novel thiazolo pyrimidine derivatives and evaluate them in vitro for their safety and anthelmintic activity against E. multilocularis metacestodes using BALB/c mice. Methods: A new series of substituted amino thiazole, hydrazinothiazole and thiazolo pyrimidine derivatives (2-6) were ...

  17. High-hardness ceramics based on boron carbide fullerite derivatives

    Science.gov (United States)

    Ovsyannikov, D. A.; Popov, M. Yu.; Perfilov, S. A.; Prokhorov, V. M.; Kulnitskiy, B. A.; Perezhogin, I. A.; Blank, V. D.

    2017-02-01

    A new type of ceramics based on the phases of fullerite derivatives and boron carbide B4C is obtained. The material is synthesized at a temperature of 1500 K and a relatively low pressure of 4 GPa; it has a high hardness of 45 GPa and fracture toughness of 15 MPa m1/2.

  18. Synthesis of peptide derivatives of aspirin and their antibiogram ...

    African Journals Online (AJOL)

    Peptide derivatives of Aspirin (1 to 8) were synthesized by using Ac2O/AcOH reaction with Salicyclic acid. Aspirin was coupled with amino acid amide and dipeptide amide and tripeptide amide using its p-nitro phenyl (NP) ester. The ester (Aspirin–ONP) was prepared using p-nitro phenol and DCC in EtOAc and was ...

  19. Synthesis and anticancer evaluation of (-1)- aretigenin derivatives

    International Nuclear Information System (INIS)

    Xu, Y.; Chen, G.

    2014-01-01

    Seven (-)-arctigenin derivatives 1-7 were designed and synthesized by using Mannich and acylation methods to improve the activity and bioavailability of (-)-arctigenin. Structures of compounds 1-7 were elucidated on the basis of spectroscopic analysis and chemical evidence. Anticancer activity of these compounds on SGC7901 was assayed in vitro. (author)

  20. Structural investigations of substituted indolizine derivatives by NMR studies

    International Nuclear Information System (INIS)

    Furdui, Bianca; Dinica, Rodica; Demeunynck, Martine; Druta, Ioan

    2008-01-01

    Owing to the increasing importance of indolizine heterocycles in the field of biology and pharmacology we have synthesized and investigated the obtained heterocycles by NMR techniques. In order to investigate the substituent effects on the spectroscopic properties, a series of indolizine derivatives were studied by 1 H-NMR, 13 C-NMR and 2D NMR (GCOSY, GHMBC and GHMQC spectra). (authors)

  1. Synthesis of a 2-Furylpyrazoline Derivative Using Microwave Irradiation

    Directory of Open Access Journals (Sweden)

    Suban Syed Shafi

    2009-08-01

    Full Text Available A simple method for the synthesis of pyrazoline derivative containing furan moiety was developed. Thus, 5-(6-bromo-1,3-benzodioxol-5-yl-3-(2-furyl-1-(3-methyl-phenyl-4,5-dihydro-1H-pyrazole was synthesized using microwave irradiation and it was characterized by NMR, IR, and LCMS.

  2. A convenient synthesis of pyrandione derivatives using P ...

    African Journals Online (AJOL)

    -pyran-2,4(3H)-dione) derivatives (3c-e) has been synthesized by the convenient ultrasound-mediated condensation of a diamine with dehydroacetic acid in the presence of a catalytic amount of p-toluenesulfonic acid. The structure of all ...

  3. a convenient synthesis of pyrandione derivatives using p ...

    African Journals Online (AJOL)

    N. Benosmane

    2016-09-01

    Sep 1, 2016 ... p- toluenesulfonic acid. The structure of all synthesized compounds was elucidated by IR spectroscopy,. 1. H NMR spectroscopic spectra, elemental analysis, and mass spectroscopy. A tautomeric form for the derivatives species is also proposed. Keywords: Dehydroacetic acid; Schiff base; Condensation; ...

  4. Ammonium derivatives of chromenones and quinolinones as lead ...

    Indian Academy of Sciences (India)

    A series of novel ammonium derivatives were synthesized and examined for their antimicrobial efficacy. Comparison of antimicrobial spectrum revealed that compounds 9, 11, 16 and 23 had strong potential against pathogens in vitro. Cytotoxicity results showed compound 9 to be least toxic, it is non-toxic to A549 and U87 ...

  5. Interest rate derivatives

    DEFF Research Database (Denmark)

    Svenstrup, Mikkel

    This Ph.D. thesis consists of four self-contained essays on valuation of interest rate derivatives. In particular derivatives related to management of interest rate risk care are considered.......This Ph.D. thesis consists of four self-contained essays on valuation of interest rate derivatives. In particular derivatives related to management of interest rate risk care are considered....

  6. Substitution of conventional high-temperature syntheses of inorganic compounds by near-room-temperature syntheses in ionic liquids

    KAUST Repository

    Groh, Matthias Friedrich

    2013-01-01

    The high-temperature syntheses of the low-valent halogenides P2I4, Te2Br, α-Te4I4, Te4(Al2Cl7)2, Te4(Bi6Cl20), Te8(Bi4Cl14),Bi8(AlCl4)2, Bi6Cl7,and Bi6Br7, as well as of WSCl4 andWOCl4 have been replaced by resource-efficient low-temperature syntheses in room temperature ionic liquids (RTILs). The simple one-pot syntheses generally do not require elaborate equipment such as twozone furnaces or evacuated silica ampoules. Compared to the published conventional approaches, reduction of reaction time (up to 80%) and temperature (up to 500 K) and, simultaneously, an increase in yield were achieved. In the majority of cases, the solid products were phase-pure. X-Ray diffraction on single crystals (redetermination of 11 crystal structures) has demonstrated that the quality of the crystals from RTILs is comparable to that of products obtained by chemical transport reactions. © 2013 Verlag der Zeitschrift für Naturforschung, Tübingen.

  7. Synthesis and Evaluation of Essential Oil-Derived β-Methoxyacrylate Derivatives as High Potential Fungicides

    Directory of Open Access Journals (Sweden)

    Haihuan Su

    2017-05-01

    Full Text Available Essential oils (EOs are plant-derived aroma compounds with a wide range of biological activity, but their actions are slow, and they are typically unstable to light or heat, difficult to extract and so on. To find highly potential fungicides derived from natural EOs, a series of essential oil-based β-methoxyacrylate derivatives have been designed and synthesized. The target compounds have been screened for their potential fungicidal activity against eleven species of plant pathogen fungi, including Alternaria alternata, Phomopsis adianticola, Pestalotiopsis theae, Sclerotinia sclerotiorum, etc. Compared with intermediates I, the parent essential oils and azoxystrobin, almost all of essential oil-based β-methoxyacrylate derivatives exhibited significantly better fungicidal activity. Further investigation revealed that some compounds showed remarkable inhibitory activities against Pestalotiopsis theae, Phomopsis adianticola, Sclerotinia sclerotiorum and Magnapothe grisea at different concentrations in contrast to the commercial product azoxystrobin. Compound II-8 exhibited particularly significant fungicidal activity.

  8. Generalized Riemann derivative

    Directory of Open Access Journals (Sweden)

    Sorin Radulescu

    2013-03-01

    Full Text Available Initiated by Marshall Ash in 1966, the study of generalized Riemann derivative draw significant attention of the mathematical community and numerous studies where carried out since then. One of the major areas that benefits from these developments is the numerical analysis, as the use of generalized Riemann derivatives leads to solving a wider class of problems that are not solvable with the classical tools. This article studies the generalized Riemann derivative and its properties and establishes relationships between Riemann generalized derivative and the classical one. The existence of classical derivative implies the existence of the Riemann generalized derivative, and we study conditions necessary for the generalized Riemann derivative to imply the existence of the classical derivative. Furthermore, we provide conditions on the generalized Riemann derivative that are sufficient for the existence of the classical derivative.

  9. Proteins synthesized and secreted by larvae of the ectoparasitic wasp, Eulophus pennicornis.

    Science.gov (United States)

    Richards, E H; Edwards, J P

    2001-03-01

    A microscopic examination of Eulophus pennicornis larvae on their host Lacanobia oleracea, revealed that peristaltic waves travelled from the anterior to posterior end of the feeding wasp larvae, and vice versa. In addition, when wasp larvae were immersed in PBS in vitro, they released a variety of proteins, with molecular weights ranging from (at least) 14 to 200 kDa. Amongst these was a protein with an estimated molecular weight similar to that of the 27 kDa parasitism-specific protein (PSP) detected in plasma from parasitized L. oleracea [Richards and Edwards, Insect Biochem Mol Biol 29:557-569 (1999)]. Similar results were obtained when the wasp larvae were incubated on balls of cotton wool soaked in tissue culture medium or sucrose, i.e., conditions that resemble their natural feeding behaviour. These results (and others) indicate that the wasp larvae release proteins, putatively through their mouth. Protein synthesis studies using (35)S-methionine indicated that the wasp larvae synthesize and secrete a variety of proteins in vitro, including one with a molecular weight corresponding to that of the L. oleracea 27 kDa PSP. As expected, only a portion of the total proteins synthesized by the parasitoid larvae were subsequently secreted. In addition, the autoradiogram of secreted proteins contained significantly fewer bands than silver-stained SDS gels of proteins released into PBS or onto cotton wool. Thus, some of the additional bands detected on the latter gels are thought to represent proteins that were not of wasp origin. Instead, these proteins released by the wasp larvae are speculated to be derived from their gut and, as such, probably represent proteins derived from host haemolymph and ingested during feeding. This possibility was supported by an electrophoretic analysis of homogenate supernatants prepared from wasp larvae with or without their gut contents. These studies indicated that the gut contents of the larval parasitoid contributes several

  10. Zeolite Synthesized from Coal Fly Ash Produced by a Gasification Process for Ni2+ Removal from Water

    Directory of Open Access Journals (Sweden)

    Yixin Zhang

    2018-03-01

    Full Text Available There are increasing demands and great potential of coal gasification in China, but there is a lack of studies focused on the disposal and utilization of coal fly ash produced by the gasification process. In this study, a coal fly ash sample derived from a gasifier in Jincheng, China, was utilized as raw material for the synthesis of zeolite by alkali fusion followed by hydrothermal treatments. The effects of operation conditions on the cation exchange capacity (CEC of synthesized zeolite were investigated. The synthesized zeolite with the highest CEC (270.4 meq/100 g, with abundant zeolite X and small amount of zeolite A, was produced by 1.5 h alkali fusion under 550 °C with NaOH/coal fly ash ratio 1.2 g/g followed by 15 h hydrothermal treatment under 90 °C with liquid/solid ratio 5 mL/g and applied in Ni2+ removal from water. The removal rate and the adsorption capacity of Ni2+ from water by the synthesized zeolite were determined at the different pH, contact time, adsorbent dose and initial Ni2+ concentration. The experimental data of adsorption were interpreted in terms of Freundlich and Langmuir equations. The adsorption of Ni2+ by the synthesized zeolite was found to fit sufficient using the Langmuir isotherm. More than 90% of Ni2+ in water could be removed by synthesized zeolite under the proper conditions. We show that the coal fly ash produced by the gasification process has great potential to be used as an alternative and cheap source in the production of adsorbents.

  11. Synthesis and Antimicrobial Activity of Furochromone, Benzofuran and Furocoumarin Derivatives Bearing Sulfonyl Moiety

    Directory of Open Access Journals (Sweden)

    Sadia A. Hessein

    2016-06-01

    Full Text Available New visnagin-9-sulfonamide derivatives 3 and 4a−c were synthesized through the reaction of visnagin-9-sulfonyl chloride 2 with amino compounds. Acetylation of compounds 4b and 4c gave the monoacetyl and diacetyl derivatives 5 and 6, respectively. Diazotization reaction of compound 4b afforded the corresponding benzotriazole derivative 8. Pyrazole and thiopyrimidine derivatives 9 and 10 were obtained via the opening of pyrone ring upon reaction of compound 3 with hydrazine hydrate and thiourea, respectively. In addition, hydrolysis of compound 3 with potassium hydroxide furnished the visnaginone derivative 11 which used as starting material for synthesize benzofuran derivatives 12−14 and bergaptene derivatives 15−17. The synthesized compounds were tested for antimicrobial activity. Furochromone derivatives 3, 4a−c, 5, 6 and 8 (visnagin-9-sulfonamide derivatives demonstrate moderate antibacterial and antifungal activities compared with the antibacterial and antifungal activites of the standard drugs. Benzofuran derivatives 11−14 (visnaginone derivatives showed the lowest antimicrobial activity among all the compounds investigated in this study. Furocoumarin derivatives 15a,b, 16 and 17 (furobenzopyransulfonamide [bergaptensulfonamides] are moderately active against all the tested strains. This work is licensed under a Creative Commons Attribution 4.0 International License.

  12. Analyzing and synthesizing phylogenies using tree alignment graphs.

    Directory of Open Access Journals (Sweden)

    Stephen A Smith

    Full Text Available Phylogenetic trees are used to analyze and visualize evolution. However, trees can be imperfect datatypes when summarizing multiple trees. This is especially problematic when accommodating for biological phenomena such as horizontal gene transfer, incomplete lineage sorting, and hybridization, as well as topological conflict between datasets. Additionally, researchers may want to combine information from sets of trees that have partially overlapping taxon sets. To address the problem of analyzing sets of trees with conflicting relationships and partially overlapping taxon sets, we introduce methods for aligning, synthesizing and analyzing rooted phylogenetic trees within a graph, called a tree alignment graph (TAG. The TAG can be queried and analyzed to explore uncertainty and conflict. It can also be synthesized to construct trees, presenting an alternative to supertrees approaches. We demonstrate these methods with two empirical datasets. In order to explore uncertainty, we constructed a TAG of the bootstrap trees from the Angiosperm Tree of Life project. Analysis of the resulting graph demonstrates that areas of the dataset that are unresolved in majority-rule consensus tree analyses can be understood in more detail within the context of a graph structure, using measures incorporating node degree and adjacency support. As an exercise in synthesis (i.e., summarization of a TAG constructed from the alignment trees, we also construct a TAG consisting of the taxonomy and source trees from a recent comprehensive bird study. We synthesized this graph into a tree that can be reconstructed in a repeatable fashion and where the underlying source information can be updated. The methods presented here are tractable for large scale analyses and serve as a basis for an alternative to consensus tree and supertree methods. Furthermore, the exploration of these graphs can expose structures and patterns within the dataset that are otherwise difficult to

  13. Rotational spectrum of formaldehyde reinvestigated using a photomixing THz synthesizer

    Science.gov (United States)

    Eliet, Sophie; Cuisset, Arnaud; Guinet, Mickaël; Hindle, Francis; Mouret, Gaël; Bocquet, Robin; Demaison, Jean

    2012-09-01

    Approximately 60 pure rotational frequency transitions of formaldehyde in its ground state have been measured with sub-MHz uncertainty in the 0.7-1.8 THz frequency range using a photomixing THz synthesizer locked onto a frequency comb. The frequencies associated with previous submillimeter and infrared data have been included in a fit providing a new set of improved molecular parameters. The assignment of each line was checked using the usual statistical diagnostics. Finally, the ability of the continuous-wave spectrometer coupled to a multipass-cell to measure THz rotational transitions of H2CO in the 31, 41 and 61 vibrational states was demonstrated.

  14. Accurate simulation of Raman amplified lightwave synthesized frequency sweeper

    DEFF Research Database (Denmark)

    Pedersen, Anders Tegtmeier; Olesen, Anders Sig; Rottwitt, Karsten

    2011-01-01

    with constant peak power and no significant growth of noise. The numerical simulation is based on careful measurements of the physical properties of the individual components and a well established Raman amplifier model. Very good agreement between the measured and the simulated data is found. (C) 2011 Optical......A lightwave synthesized frequency sweeper using a Raman amplifier for loss compensation is presented together with a numerical model capable of predicting the shape of individual pulses as well as the overall envelope of more than 100 pulses. The generated pulse envelope consists of 116 pulses...

  15. Integrated digital superconducting logic circuits for the quantum synthesizer. Report

    International Nuclear Information System (INIS)

    Buchholz, F.I.; Kohlmann, J.; Khabipov, M.; Brandt, C.M.; Hagedorn, D.; Balashov, D.; Maibaum, F.; Tolkacheva, E.; Niemeyer, J.

    2006-11-01

    This report presents the results, which were reached in the framework of the BMBF cooperative plan ''Quantum Synthesizer'' in the partial plan ''Integrated Digital Superconducting Logic Circuits''. As essential goal of the plan a novel instrument on the base of quantum-coherent superconducting circuits should be developed. which allows to generate praxis-relevant wave forms with quantum accuracy, the quantum synthesizer. The main topics of development of the reported partial plan lied at the one hand in the development of integrated, digital, superconducting circuit in rapid-single-flux (RSFQ) quantum logics for the pattern generator of the quantum synthesizer, at the other hand in the further development of the fabrication technology for the aiming of high circuit complexity. In order to fulfil these requirements at the PTB a new design system was implemented, based on the software of Cadence. Together with the required RSFQ extensions for the design of digital superconducting circuits was a platform generated, on which the reachable circuit complexity is exclusively limited by the technology parameters of the available fabrication technology: Physical simulations are with PSCAN up to a complexity of more than 1000 circuit elements possible; furthermore VHDL allows the verification of arbitrarily large circuit architectures. In accordance for this the production line at the PTB was brought to a level, which allows in Nb/Al-Al x O y /Nb SIS technology implementation the fabrication of highly integrable RSFQ circuit architectures. The developed and fabricated basic circuits of the pattern generator have proved correct functionality and reliability in the measuring operation. Thereby for the circular RSFQ shift registers a key role as local memories in the construction of the pattern generator is devolved upon. The registers were realized with the aimed bit lengths up to 128 bit and with reachable signal-processing speeds of above 10 GHz. At the interface RSFQ

  16. Mechanical characterization of hotplate synthesized vanadium oxide nanobelts

    International Nuclear Information System (INIS)

    Zhu Yanwu; Zhang Yousheng; Dai Ling; Cheong, Fook-Chiong; Tan, Vincent; Sow, Chorng-Haur; Lim, Chwee-Teck

    2010-01-01

    Vanadium oxide nanobelts have been synthesized on Si or SiN substrates by simply heating vanadium foils on a hotplate. As-grown nanobelts were characterized as V 2 O 5 .nH 2 O (0.3 2 O 5 phase and a polycrystalline structure was observed. The Young's modulus of the annealed nanobelts showed more consistent values at an average of 28.9 GPa, lower than the calculated modulus of bulk α-V 2 O 5 at 68 GPa.

  17. Bio-inspired routes for synthesizing efficient nanoscale platinum electrocatalysts

    Energy Technology Data Exchange (ETDEWEB)

    Cha, Jennifer N. [Univ. of California, San Diego, CA (United States); Wang, Joseph [Univ. of California, San Diego, CA (United States)

    2014-08-31

    The overall objective of the proposed research is to use fundamental advances in bionanotechnology to design powerful platinum nanocrystal electrocatalysts for fuel cell applications. The new economically-viable, environmentally-friendly, bottom-up biochemical synthetic strategy will produce platinum nanocrystals with tailored size, shape and crystal orientation, hence leading to a maximum electrochemical reactivity. There are five specific aims to the proposed bio-inspired strategy for synthesizing efficient electrocatalytic platinum nanocrystals: (1) isolate peptides that both selectively bind particular crystal faces of platinum and promote the nucleation and growth of particular nanocrystal morphologies, (2) pattern nanoscale 2-dimensional arrays of platinum nucleating peptides from DNA scaffolds, (3) investigate the combined use of substrate patterned peptides and soluble peptides on nanocrystal morphology and growth (4) synthesize platinum crystals on planar and large-area carbon electrode supports, and (5) perform detailed characterization of the electrocatalytic behavior as a function of catalyst size, shape and morphology. Project Description and Impact: This bio-inspired collaborative research effort will address key challenges in designing powerful electrocatalysts for fuel cell applications by employing nucleic acid scaffolds in combination with peptides to perform specific, environmentally-friendly, simultaneous bottom-up biochemical synthesis and patterned assembly of highly uniform and efficient platinum nanocrystal catalysts. Bulk synthesis of nanoparticles usually produces a range of sizes, accessible catalytic sites, crystal morphologies, and orientations, all of which lead to inconsistent catalytic activities. In contrast, biological systems routinely demonstrate exquisite control over inorganic syntheses at neutral pH and ambient temperature and pressures. Because the orientation and arrangement of the templating biomolecules can be precisely

  18. Methods to Design and Synthesize Antibody-Drug Conjugates (ADCs

    Directory of Open Access Journals (Sweden)

    Houzong Yao

    2016-02-01

    Full Text Available Antibody-drug conjugates (ADCs have become a promising targeted therapy strategy that combines the specificity, favorable pharmacokinetics and biodistributions of antibodies with the destructive potential of highly potent drugs. One of the biggest challenges in the development of ADCs is the application of suitable linkers for conjugating drugs to antibodies. Recently, the design and synthesis of linkers are making great progress. In this review, we present the methods that are currently used to synthesize antibody-drug conjugates by using thiols, amines, alcohols, aldehydes and azides.

  19. Annual reports in inorganic and general syntheses 1976

    CERN Document Server

    Zimmer, Hans

    2013-01-01

    Annual Reports in Inorganic and General Syntheses-1976 presents an annual review of synthetically useful information that would prove beneficial to nearly all organic chemists, both specialist and nonspecialist in synthesis. It should help relieve some of the information storage burden of the specialist and should aid the nonspecialist who is seeking help with a specific problem to become rapidly aware of recent synthetic advances.This is the fifth volume of ARIGS and is organized along the lines developed for the preceding volumes. The authors were encouraged to use synthetic aspects as their

  20. A Simple Method to Synthesize Cadmium Hydroxide Nanobelts

    Directory of Open Access Journals (Sweden)

    Zhang DE

    2008-01-01

    Full Text Available AbstractCd(OH2nanobelts have been synthesized in high yield by a convenient polyol method for the first time. XRD, XPS, FESEM, and TEM were used to characterize the product, which revealed that the product consisted of belt-like crystals about 40 nm in thickness and length up to several hundreds of micrometers. Studies found that the viscosity of the solvent has important influence on the morphology of the final products. The optical absorption spectrum indicates that the Cd(OH2nanobelts have a direct band gap of 4.45 eV.

  1. Concrete Embedded Dye-Synthesized Photovoltaic Solar Cell

    OpenAIRE

    Hosseini, T.; Flores-Vivian, I.; Sobolev, K.; Kouklin, N.

    2013-01-01

    This work presents the concept of a monolithic concrete-integrated dye-synthesized photovoltaic solar cell for optical-to-electrical energy conversion and on-site power generation. The transport measurements carried out in the dark revealed the presence of VOC of ~190?mV and ISC of ~9??A, induced by the electrochemical conversion of concrete-supplied ionic impurities at the electrodes. The current-voltage measurements performed under illumination at incident optical powers of ~46?mW confirmed...

  2. Proposal of an Algorithm to Synthesize Music Suitable for Dance

    Science.gov (United States)

    Morioka, Hirofumi; Nakatani, Mie; Nishida, Shogo

    This paper proposes an algorithm for synthesizing music suitable for emotions in moving pictures. Our goal is to support multi-media content creation; web page design, animation films and so on. Here we adopt a human dance as a moving picture to examine the availability of our method. Because we think the dance image has high affinity with music. This algorithm is composed of three modules. The first is the module for computing emotions from an input dance image, the second is for computing emotions from music in the database and the last is for selecting music suitable for input dance via an interface of emotion.

  3. Comparative sinterability of combustion synthesized and commercial titanium carbides

    International Nuclear Information System (INIS)

    Manley, B.W.

    1984-11-01

    The influence of various parameters on the sinterability of combustion synthesized titanium carbide was investigaged. Titanium carbide powders, prepared by the combustion synthesis process, were sintered in the temperature range 1150 to 1600 0 C. Incomplete combustion and high oxygen contents were found to be the cause of reduced shrinkage during sintering of the combustion syntheized powders when compared to the shrinkage of commercial TiC. Free carbon was shown to inhibit shrinkage. The activation energy for sintering was found to depend on stoichiometry (C/Ti). With decreasing C/Ti, the rate of sintering increased. 29 references, 16 figures, 13 tables

  4. A facile route to synthesize nanogels doped with silver nanoparticles

    Science.gov (United States)

    Coll Ferrer, M. Carme; Ferrier, Robert C.; Eckmann, David M.; Composto, Russell J.

    2013-01-01

    In this study, we describe a simple method to prepare hybrid nanogels consisting of a biocompatible core-shell polymer host containing silver nanoparticles. First, the nanogels (NG, 160 nm) containing a lysozyme rich core and a dextran rich shell, are prepared via Maillard and heat-gelation reactions. Second, silver nanoparticles (Ag NPs, 5 nm) are synthesized "in situ" in the NG solution without requiring additional reducing agents. This approach leads to stable Ag NPs located in the NG. Furthermore, we demonstrate that the amount of Ag NPs in the NG can be tuned by varying silver precursor concentration. Hybrid nanogels with silver nanoparticles have potential in antimicrobial, optical, and therapeutic applications.

  5. SEARCH AUTOMATION OF BINARIZATION OPTIMUM LEVEL FOR SYNTHESIZED HOLOGRAMS

    Directory of Open Access Journals (Sweden)

    Oleg V. Nikanorov

    2017-11-01

    Full Text Available The paper considers the features of synthesized holograms suitable for practical use. It is established that binary holograms are the first of all suitable ones for successful application in practice. In order to select the most suitable (optimal level of hologram binarization, we propose a criterion for estimating the quality of an image reconstructed with a binary hologram. An algorithm is developed to find the optimal level. On the basis of the conducted experiments it is established that the introduction of the developed module gives the possibility to reduce the search time of the optimal binarization level of the hologram by eleven times in comparison with manual search.

  6. Novel isoquinoline derivatives as antimicrobial agents.

    Science.gov (United States)

    Galán, Abraham; Moreno, Laura; Párraga, Javier; Serrano, Ángel; Sanz, Ma Jesús; Cortes, Diego; Cabedo, Nuria

    2013-06-01

    The wide variety of potent biological activities of natural and synthetic isoquinoline alkaloids encouraged us to develop novel antimicrobial isoquinoline compounds. We synthesized a variety of differently functionalized 1-pentyl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines (THIQs), including dihydroisoquinolinium salts (2 and 5), methyl pentanoate-THIQ (6), 1-pentanol-THIQ (7), ester derivatives (8-15) and carbamate derivatives (16-23). We employed classic intramolecular Bischler-Napieralski cyclodehydration to generate the isoquinoline core. All the structures were characterized by nuclear magnetic resonance and mass spectrometry. The bactericide and fungicide activities were evaluated for all the synthesized compounds and structure-activity relationships were established. Many compounds exhibited high and broad-range bactericidal activity. Fluorophenylpropanoate ester 13 and the halogenated phenyl- (17, 18) and phenethyl carbamates (21, 22) exerted the most remarkable bactericidal activity. However, few compounds displayed antifungal activity against most of the fungi tested. Among them, chlorinated derivatives like chlorobenzoate and chlorophenylpropanoate esters (10 and 14, respectively) and chlorophenethyl carbamate 22, exhibited the greatest antifungal activity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Stereospecific Syntheses of Enaminonitriles and β-Enaminoesters via Domino Ring-Opening Cyclization (DROC) of Activated Cyclopropanes with Pronucleophilic Malononitriles.

    Science.gov (United States)

    Saha, Amrita; Bhattacharyya, Aditya; Talukdar, Ranadeep; Ghorai, Manas K

    2018-02-16

    Two novel synthetic protocols for the syntheses of highly functionalized five-membered carbocyclic enaminonitriles and β-enaminoesters have been developed via domino ring-opening cyclization (DROC) and DROC/decarboxylative tautomerization of activated cyclopropanes with malononitrile pronucleophiles, respectively. Both of the efficient strategies (yield up to 93%) have been generalized with various donor-acceptor and acceptor cyclopropanes as well as with malononitrile derivatives. The stereospecific variants of the two S N 2-type DROC strategies have also been developed by employing enantiopure donor-acceptor (DA) cyclopropanes to synthesize the corresponding nonracemic products with excellent stereoselectivities (dr up to >99:1, ee up to >99%).

  8. Cross-Linking Mast Cell Specific Gangliosides Stimulates the Release of Newly Formed Lipid Mediators and Newly Synthesized Cytokines

    Directory of Open Access Journals (Sweden)

    Edismauro Garcia Freitas Filho

    2016-01-01

    Full Text Available Mast cells are immunoregulatory cells that participate in inflammatory processes. Cross-linking mast cell specific GD1b derived gangliosides by mAbAA4 results in partial activation of mast cells without the release of preformed mediators. The present study examines the release of newly formed and newly synthesized mediators following ganglioside cross-linking. Cross-linking the gangliosides with mAbAA4 released the newly formed lipid mediators, prostaglandins D2 and E2, without release of leukotrienes B4 and C4. The effect of cross-linking these gangliosides on the activation of enzymes in the arachidonate cascade was then investigated. Ganglioside cross-linking resulted in phosphorylation of cytosolic phospholipase A2 and increased expression of cyclooxygenase-2. Translocation of 5-lipoxygenase from the cytosol to the nucleus was not induced by ganglioside cross-linking. Cross-linking of GD1b derived gangliosides also resulted in the release of the newly synthesized mediators, interleukin-4, interleukin-6, and TNF-α. The effect of cross-linking the gangliosides on the MAP kinase pathway was then investigated. Cross-linking the gangliosides induced the phosphorylation of ERK1/2, JNK1/2, and p38 as well as activating both NFκB and NFAT in a Syk-dependent manner. Therefore, cross-linking the mast cell specific GD1b derived gangliosides results in the activation of signaling pathways that culminate with the release of newly formed and newly synthesized mediators.

  9. Mechanochemically synthesized Al2O3-TiC nanocomposite

    International Nuclear Information System (INIS)

    Mohammad Sharifi, E.; Karimzadeh, F.; Enayati, M.H.

    2010-01-01

    Al 2 O 3 -TiC nanocomposite was synthesized by ball milling of aluminum, titanium oxide and graphite powder mixtures. Effect of the milling time and heat treatment temperatures were investigated. The structural evolution of powder particles after different milling times was studied by X-ray diffractometry and scanning electron microscopy. The results showed that after 40 h of ball milling the Al/TiO 2 /C reacted with a self-propagating combustion mode producing Al 2 O 3 -TiC nanocomposite. In final stage of milling, alumina and titanium carbide crystallite sizes were less than 10 nm. After annealing at 900 o C for 1 h, Al 2 O 3 and TiC crystallite sizes remained constant, however increasing annealing temperature to 1200 o C increased Al 2 O 3 and TiC crystallite size to 65 and 30 nm, respectively. No phase change was observed after annealing of the synthesized Al 2 O 3 -TiC powder.

  10. Safety evaluation of an enzymatically-synthesized glycogen (ESG).

    Science.gov (United States)

    Tafazoli, Shahrzad; Wong, Andrea W; Kajiura, Hideki; Kakutani, Ryo; Furuyashiki, Takashi; Takata, Hiroki; Kuriki, Takashi

    2010-01-01

    An enzymatically-synthesized glycogen (ESG), intended for use as a food ingredient, was investigated for potential toxicity. ESG is synthesized in vitro from short-chain amylose by the co-operative action of branching enzyme and amylomaltase. In an acute toxicity study, oral administration of ESG to Sprague-Dawley rats at a dose of 2000 mg/kg body weight did not result in any signs of toxicity. ESG did not exhibit mutagenic activity in an in vitro bacterial reverse mutation assay. In a subchronic toxicity study, increased cecal weights noted in the mid- (10%) and high-dose (30%) animals are common findings in rodents fed excess amounts of carbohydrates that increase osmotic value of the cecal contents, and thus were considered a physiological rather than toxicological response. The hematological and histopathological effects observed in the high-dose groups were of no toxicological concern as they were secondary to the physiological responses resulting from the high carbohydrate levels in the test diets. The no-observed-adverse-effect level for ESG in rats was therefore established to be 30% in the diet (equivalent to approximately 18 and 21 g/kg body weight/day for male and female rats, respectively). These results support the safety of ESG as a food ingredient for human consumption. Copyright 2010 Elsevier Inc. All rights reserved.

  11. Dynamic balancing of mechanisms and synthesizing of parallel robots

    CERN Document Server

    Wei, Bin

    2016-01-01

    This book covers the state-of-the-art technologies in dynamic balancing of mechanisms with minimum increase of mass and inertia. The synthesis of parallel robots based on the Decomposition and Integration concept is also covered in detail. The latest advances are described, including different balancing principles, design of reactionless mechanisms with minimum increase of mass and inertia, and synthesizing parallel robots. This is an ideal book for mechanical engineering students and researchers who are interested in the dynamic balancing of mechanisms and synthesizing of parallel robots. This book also: ·       Broadens reader understanding of the synthesis of parallel robots based on the Decomposition and Integration concept ·       Reinforces basic principles with detailed coverage of different balancing principles, including input torque balancing mechanisms ·       Reviews exhaustively the key recent research into the design of reactionless mechanisms with minimum increase of mass a...

  12. Discrimination of synthesized English vowels by American and Korean listeners

    Science.gov (United States)

    Yang, Byunggon

    2004-05-01

    This study explored the discrimination of synthesized English vowel pairs by 27 American and Korean, male and female listeners. The average formant values of nine monophthongs produced by ten American English male speakers were employed to synthesize the vowels. Then, subjects were instructed explicitly to respond to AX discrimination tasks in which the standard vowel was followed by another one with the increment or decrement of the original formant values. The highest and lowest formant values of the same vowel quality were collected and compared to examine patterns of vowel discrimination. Results showed that the American and Korean groups discriminated the vowel pairs almost identically and their center formant frequency values of the high and low boundary fell almost exactly on those of the standards. In addition, the acceptable range of the same vowel quality was similar among the language and gender groups. The acceptable thresholds of each vowel formed an oval to maintain perceptual contrast from adjacent vowels. Pedagogical implications of those findings are discussed.

  13. Plasmonic Luneburg lens antenna synthesized by metasurfaces with hexagonal lattices.

    Science.gov (United States)

    Chen, Kuang Cheng; Yang, Jiun Wen; Yang, Yueh-Chieh; Khin, Chang Fu; Kehn, M Ng Mou

    2017-10-30

    The metasurface lens composing of 2D periodic metallic patches on a grounded dielectric slab possesses several advantages such as being light, low-profile, compact, and also cheap to manufacture. In this paper, a Luneburg lens synthesized by a metasurface and designated for use as a surface wave antenna is proposed. Two types of unit cell will be compared, one whose surface wave modal dispersion varies significantly with the grazing direction and another that does not. In the context of being applied as surface wave antennas, it will be shown that the Luneburg lens synthesized by the latter kind of unit cell provides improved performance as compared to the former. Several aperture sub-efficiencies of the metasurface-based Luneburg-lens antenna shall be used for the characterization of the radiation. A prototype of the designed lens antenna has also been manufactured. Measurement results agree well with theoretical predictions and the efficacy of this device over a fairly wide bandwidth has been experimentally demonstrated.

  14. Protein-synthesizing machinery in the axon compartment.

    Science.gov (United States)

    Koenig, E; Giuditta, A

    1999-03-01

    Contrary to the prevailing view that the axon lacks the capacity to synthesize proteins, a substantial body of evidence points to the existence of a metabolically active endogenous translational machinery. The machinery appears to be largely localized in the cortical zone of the axon, where, in vertebrate axons, it is distributed longitudinally as intermittent, discrete domains, called periaxoplasmic plaques. Studies, based on translation assays and probes of RNA transcripts in axon models such as the squid giant axon and selected vertebrate axons, provide evidence of locally synthesized proteins, most of which appear to be constituents of the slow axoplasmic transport rate groups. Metabolic and molecular biological findings are consistent with the view that the synthesis of proteins undergoing local turnover in the axonal compartment of macroneurons depends on the activity of an endogenous translational machinery. The documented presence of a metabolically active machinery in presynaptic terminals of squid photoreceptor neurons is also described. Finally, potential sources of axoplasmic RNAs comprising the machinery, which may include the ensheathing cell of the axon, as well as the cognate cell body, are also discussed.

  15. Evolutionary selection of enzymatically synthesized semiconductors from biomimetic mineralization vesicles

    Energy Technology Data Exchange (ETDEWEB)

    Bawazer, Lukmaan A.; Izumi, Michi; Kolodin, Dmitriy; Neilson, James R.; Schwenzer, Birgit; Morse, Daniel E. (UCSB)

    2012-10-29

    The way nature evolves and sculpts materials using proteins inspires new approaches to materials engineering but is still not completely understood. Here, we present a cell-free synthetic biological platform to advance studies of biologically synthesized solid-state materials. This platform is capable of simultaneously exerting many of the hierarchical levels of control found in natural biomineralization, including genetic, chemical, spatial, structural, and morphological control, while supporting the evolutionary selection of new mineralizing proteins and the corresponding genetically encoded materials that they produce. DNA-directed protein expression and enzymatic mineralization occur on polystyrene microbeads in water-in-oil emulsions, yielding synthetic surrogates of biomineralizing cells that are then screened by flow sorting, with light-scattering signals used to sort the resulting mineralized composites differentially. We demonstrate the utility of this platform by evolutionarily selecting newly identified silicateins, biomineralizing enzymes previously identified from the silica skeleton of a marine sponge, for enzyme variants capable of synthesizing silicon dioxide (silica) or titanium dioxide (titania) composites. Mineral composites of intermediate strength are preferentially selected to remain intact for identification during cell sorting, and then to collapse postsorting to expose the encoding genes for enzymatic DNA amplification. Some of the newly selected silicatein variants catalyze the formation of crystalline silicates, whereas the parent silicateins lack this ability. The demonstrated bioengineered route to previously undescribed materials introduces in vitro enzyme selection as a viable strategy for mimicking genetic evolution of materials as it occurs in nature.

  16. Metal Borohydrides synthesized from metal borides and metal hydrides

    DEFF Research Database (Denmark)

    Sommer, Sanna

    2014-01-01

    Metal Borohydrides Synthesized from Metal Borides and Metal Hydrides Alexander Fogha, Sanna Sommera, Kasper T. Møllera, T. R. Jensena aCenter for Materials Crystallography (CMC), Interdisciplinary Nanoscience Center (iNANO) and Chemistry Department, Aarhus University, Langelandsgade 140, DK-8000...... Aarhus C, Denmark email: gallafogh@hotmail.com / sanna-sommer@hotmail.com Magnesium boride, MgB2, ball milled with MH (M = Li, Na, Ca) followed by hydrogenation under high hydrogen pressure, readily forms the corresponding metal borohydrides, M(BH4)x (M = Li, Na, Ca) and MgH2 according to reaction scheme...... and Ca(BH4)2, respectively [3,4]. An attempt to synthesize alkali and alkaline earth metal borohydrides from various borides by ball milling under high hydrogen pressure is presented here. MgB2, AlB2 and CaB6 have been milled with MHx (M = Li, Na, Mg, Ca) at p(H2) = 110 bar for 24 hours. All samples were...

  17. Photothermal stability of biologically and chemically synthesized gold nanoprisms

    Science.gov (United States)

    Klekotko, Magdalena; Olesiak-Banska, Joanna; Matczyszyn, Katarzyna

    2017-10-01

    We report here the influence of the irradiation with femtosecond laser pulses on the gold nanoprisms synthesized using biological and chemical methods. For the bio-mediated growth, we used plant extract as a source of reducing, structure-directing, and stabilizing agents, while for the chemical method, we applied three-step protocol, involving chemicals commonly used in the synthesis of nanostructures. Exposition of the nanostructures to the laser beam causes morphological changes, which affect their extinction spectra. These modifications were followed using absorption spectroscopy and transmission electron microscopy. The observed effects depend on the applied laser power and excitation wavelength. Under resonance conditions, rounding of the tips of triangular nanoparticles and transformation towards more stable, spherical form were noticed. These changes were faster under higher laser power. Such shape modifications were weaker under off-resonance conditions. Moreover, chemically synthesized gold nanoprisms were less susceptible to the morphological changes than those obtained using plant extract; however, their colloidal stability was disrupted by long-time irradiation. [Figure not available: see fulltext.

  18. Peptide-templated noble metal catalysts: syntheses and applications.

    Science.gov (United States)

    Wang, Wei; Anderson, Caleb F; Wang, Zongyuan; Wu, Wei; Cui, Honggang; Liu, Chang-Jun

    2017-05-01

    Noble metal catalysts have been widely used in many applications because of their high activity and selectivity. However, a controllable preparation of noble metal catalysts still remains as a significant challenge. To overcome this challenge, peptide templates can play a critical role in the controllable syntheses of catalysts owing to their flexible binding with specific metallic surfaces and self-assembly characteristics. By employing peptide templates, the size, shape, facet, structure, and composition of obtained catalysts can all be specifically controlled under the mild synthesis conditions. In addition, catalysts with spherical, nanofiber, and nanofilm structures can all be produced by associating with the self-assembly characteristics of peptide templates. Furthermore, the peptide-templated noble metal catalysts also reveal significantly enhanced catalytic behaviours compared with conventional catalysts because the electron conductivity, metal dispersion, and reactive site exposure can all be improved. In this review, we summarize the research progresses in the syntheses of peptide-templated noble metal catalysts. The applications of the peptide-templated catalysts in organic reactions, photocatalysis, and electrocatalysis are discussed, and the relationship between structure and activity of these catalysts are addressed. Future opportunities, including new catalytic materials designed by using biological principles, are indicated to achieve selective, eco-friendly, and energy neutral synthesis approaches.

  19. Synthesizing Iron Oxide Nanostructures: The Polyethylenenemine (PEI) Role

    KAUST Repository

    Mozo, Sergio Lentijo

    2017-01-12

    Controlled synthesis of anisotropic iron oxide nanoparticles is a challenge in the field of nanomaterial research that requires an extreme attention to detail. In particular, following up a previous work showcasing the synthesis of magnetite nanorods (NRs) using a two-step approach that made use of polyethylenenemine (PEI) as a capping ligand to synthesize intermediate β-FeOOH NRs, we studied the effect and influence of the capping ligand on the formation of β-FeOOH NRs. By comparing the results reported in the literature with those we obtained from syntheses performed (1) in the absence of PEI or (2) by using PEIs with different molecular weight, we showed how the choice of different PEIs determines the aspect ratio and the structural stability of the β-FeOOH NRs and how this affects the final products. For this purpose, a combination of XRD, HRTEM, and direct current superconducting quantum interference device (DC SQUID) magnetometry was used to identify the phases formed in the final products and study their morphostructural features and related magnetic behavior.

  20. Biological activities of water-soluble fullerene derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Nakamura, S; Mashino, T [Department of Pharmaceutical Sciences, Faculty of Pharmacy, Keio University, 1-5-30 Shiba-koen, Minato-ku, Tokyo 105-8512 (Japan)], E-mail: mashino-td@pha.keio.ac.jp

    2009-04-01

    Three types of water-soluble fullerene derivatives were synthesized and their biological activities were investigated. C{sub 60}-dimalonic acid, an anionic fullerene derivative, showed antioxidant activity such as quenching of superoxide and relief from growth inhibition of E. coli by paraquat. C{sub 60}-bis(7V,7V-dimethylpyrrolidinium iodide), a cationic fullerene derivative, has antibacterial activity and antiproliferative effect on cancer cell lines. The mechanism is suggested to be respiratory chain inhibition by reactive oxygen species produced by the cationic fullerene derivative. Proline-type fullerene derivatives showed strong inhibition activities on HIV-reverse transcriptase. The IC{sub 50} values were remarkably lower than nevirapine, a clinically used anti-HIV drug. Fullerene derivatives have a big potential for a new type of lead compound to be used as medicine.

  1. The Human Nuclear Exosome Targeting Complex Is Loaded onto Newly Synthesized RNA to Direct Early Ribonucleolysis

    Directory of Open Access Journals (Sweden)

    Michal Lubas

    2015-01-01

    Full Text Available The RNA exosome complex constitutes the major nuclear eukaryotic 3′-5′ exonuclease. Outside of nucleoli, the human nucleoplasmic exosome is directed to some of its substrates by the nuclear exosome targeting (NEXT complex. How NEXT targets RNA has remained elusive. Using an in vivo crosslinking approach, we report global RNA binding sites of RBM7, a key component of NEXT. RBM7 associates broadly with RNA polymerase II-derived RNA, including pre-mRNA and short-lived exosome substrates such as promoter upstream transcripts (PROMPTs, enhancer RNAs (eRNAs, and 3′-extended products from snRNA and replication-dependent histone genes. Within pre-mRNA, RBM7 accumulates at the 3′ ends of introns, and pulse-labeling experiments demonstrate that RBM7/NEXT defines an early exosome-targeting pathway for 3′-extended snoRNAs derived from such introns. We propose that RBM7 is generally loaded onto newly synthesized RNA to accommodate exosome action in case of available unprotected RNA 3′ ends.

  2. Synthesis and 99Tcm labelling of three kinds of derivatives of β-methyl-15-phenyl pentadecanoic acid

    International Nuclear Information System (INIS)

    Lu Chunxiong; Ji Shuren; Wu Chunying; Fang Ping

    2002-01-01

    Three kinds of derivatives of β-methyl-15-phenyl pentadecanoic acid (BMPPA) are synthesized. These derivatives are characterized by IR, MS and elementary analysis. These derivatives are labelled with 99 Tc m , the labelling yields are higher than 70% confirmed by TLC and HPLC and the radiochemical purity are more than 95% after extraction

  3. Synthetic Methods of Quinoline Derivatives as Potent Anticancer Agents.

    Science.gov (United States)

    Sharma, Vaibhav; Mehta, Dinesh Kumar; Das, Rina

    2017-01-01

    On account of significant biological activities, quinoline derivatives have drawn more attention to the synthesis and biological activities in the search for new therapeutic agents. Several new synthetic approaches have been implemented to derive new molecules from quinoline and all the synthesized molecules showed effective anticancer activity. Some molecules are synthesized using quinolones as precursor reactant, which is another effective product of quinoline, also showing significant activity against malignant tumors. The presence of nitrogen in it and its ability to bind with enzymes like gyrase, topoisomerase II and kinase have also proven it with antitumor activity. This review encapsulates the recent advances in the synthesis and anticancer activity of Quinoline derivatives. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  4. Design, Synthesis and Insecticidal Activity of Novel Phenylurea Derivatives

    Directory of Open Access Journals (Sweden)

    Jialong Sun

    2015-03-01

    Full Text Available A series of novel phenylurea derivatives were designed and synthesized according to the method of active groups linkage and the principle of aromatic groups bioisosterism in this study. The structures of the novel phenylurea derivatives were confirmed based on ESI-MS, IR and 1H-NMR spectral data. All of the compounds were evaluated for the insecticidal activity against the third instars larvae of Spodoptera exigua Hiibner, Plutella xyllostella Linnaeus, Helicoverpa armigera Hubner and Pieris rapae Linne respectively, at the concentration of 10 mg/L. The results showed that all of the derivatives displayed strong insecticidal activity. Most of the compounds presented higher insecticidal activity against S. exigua than the reference compounds tebufenozide, chlorbenzuron and metaflumizone. Among the synthesized compounds, 3b, 3d, 3f, 4b and 4g displayed broad spectrum insecticidal activity.

  5. Synthesis of derivatives of tetronic acid and pulvinic acid. Total synthesis of norbadione A; Synthese de derives de l'acide tetronique et de l'acide pulvinique. Synthese totale de la norbadione A

    Energy Technology Data Exchange (ETDEWEB)

    Mallinger, A

    2008-11-15

    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.

  6. Synthesis of 5'-deoxy-5'-nucleosideacetic acid derivatives

    Science.gov (United States)

    Harada, Kazuo; Orgel, Leslie E.

    1990-01-01

    Several new 5'-deoxy-5'-nucleosideacetic acid derivatives have been synthesized by the reactions of alkoxycarbonylmethylene triphenylphosphoranes with nucleoside 5'-aldehydes. The oligomerization of adenine derivatives IIa, IIIa, IV, V and guanine derivatives IIc and IIIc in aqueous solution was studied using a water-soluble carbodiimide as a condensing agent. It is found that the saturated acid (IV) tends to cyclize to the lactone, while IIa and unsaturated acids (IIIa and V) oligomerized efficiently, especially in the presence of poly (U) as a template.

  7. Derivatives in emerging markets

    OpenAIRE

    Dubravko Mihaljek; Frank Packer

    2010-01-01

    Turnover of derivatives has grown more rapidly in emerging markets than in developed countries. Foreign exchange derivatives are the most commonly traded of all risk categories, with increasingly frequent turnover in emerging market currencies and a growing share of cross-border transactions. As the global reach of the financial centres in emerging Asia has expanded, the offshore trading of many emerging market currency derivatives has risen as well. Growth in derivatives turnover is positive...

  8. Synthesis and Biological Activity of Some 3,5-Diaryl-1-Benzothiazolopyrazoline Derivatives: Reaction of Chalcones with 2-Hyrazinobenzothiazoles

    Directory of Open Access Journals (Sweden)

    Vandana Sharma

    2009-01-01

    Full Text Available A series of 3,5-diaryl-1-benzothiazolopyrazoline derivatives were synthesized by the reaction of appropriately substituted chalcones and 2-hydrazinobenzothiazole in ethanol. The synthesized heterocycles have been characterized on the basis of their chemical properties and spectroscopic data. These compounds were tested for biological activity against a variety of test organisms.

  9. Synthesis and Biological Activity of Some 3, 5-Diarylisoxazoline Derivatives: Reaction of Substituted Chalcones with Hydroxylamine Hydrochloride

    Directory of Open Access Journals (Sweden)

    Vandana Sharma

    2010-01-01

    Full Text Available A series of 3-aryl-5-styrylisoxazoline/ 3,5-diarylisoxazoline derivatives were synthesized by the reaction of appropriately substituted chalcones and hydroxylamine hydrochloride in presence of alkali in ethanol. The synthesized heterocycles have been characterized on the basis of their chemical properties and spectroscopic data. These compounds were tested for biological activity against a variety of test organisms

  10. The Ungraded Derived Category

    OpenAIRE

    Stai, Torkil Utvik

    2012-01-01

    By means of the ungraded derived category we prove that the orbit category of the bounded derived category of an iterated tilted algebra with respect to translation is triangulated in such a way that the canonical functor from the bounded derived category to the orbit category becomes a triangle functor.

  11. Synthesis, characterization and biological evaluation of tryptamine based benzamide derivatives.

    Science.gov (United States)

    Aftab, Kiran; Aslam, Kinza; Kousar, Shazia; Nadeem, Muhammad Jawad Ul Hasan

    2016-03-01

    Benzamides and tryptamine are biologically significant compounds, therefore, various benzamide analogous of tryptamine have been efficiently synthesized using tryptamine and different benzoyl chlorides, in order to find new biologically active compounds. The resulting products were then characterized by melting point determination, calculation of Rf values and LC-MS techniques. At last, structure activity relationship (SAR) of the synthesized compounds was evaluated against two microbial strains; Bacillus subtilis and Aspergillus niger. All the five prepared products have shown high yield, sharp characterization and significant resistance against the growth of tested microorganism, providing a new range of tryptamine based benzamide derivatives having significant antimicrobial activities.

  12. Synthesis and Characterization of Biscoumarin and Benzopyrano Dicoumarin Derivatives

    International Nuclear Information System (INIS)

    Nik Khairunissa' Nik Abdullah Zawawi; Muhammad Taha; Norizan Ahmat; Nor Hadiani Ismail; Nik Khairunissa' Nik Abdullah Zawawi; Muhammad Taha; Norizan Ahmat; Nor Hadiani Ismail

    2016-01-01

    The wide-ranging biological activities of 4-hydroxycoumarin have stimulated considerable interest in this class of compounds, and various biscoumarin derivatives have been synthesized. Recently, a number of methods have been reported for the synthesis of biscoumarin by the reaction of 4-hydroxycoumarin and various aldehydes in the presence of catalysts. In the present study, a new series of biscoumarin and benzopyrano dicoumarin were synthesized and physically characterized by nuclear magnetic resonane ( 1 H and 13 C NMR), fourier transform infrared spectroscopy (FTIR), mass spectrometry (MS) and melting point. (author)

  13. Synthesis of Diethylpropione Derivatives and Their Leukocyte-Increasing Activities

    Energy Technology Data Exchange (ETDEWEB)

    Li, Chung Gang; Sun, Yi Ping; Wang, Guo Ping; Tan, Xiang Duan [Guilin Medical University, Guilin (China)

    2014-09-15

    In search of new antileukopenia agents, twenty dithiolopyrrolone derivatives were synthesized and evaluated for their leukocyte-increasing activities in normal mice. Among the synthesized compounds 4-23, compounds 5 and 6 showed significant leukocyte-increasing activity ( p < 0.01), and compounds 4, 9 and 16 had a moderate effect ( p < 0.05). Compound 5 also displayed stronger leukocyte-increasing activity than that of the positive recombinant human granulocyte colony stimulating factor (rhG-CSF). Above all, compound 5 would be a potential antileukopenia agent which deserved further research.

  14. Novel Synthesis of Hydrazide-Hydrazone Derivatives and Their Utilization in the Synthesis of Coumarin, Pyridine, Thiazole and Thiophene Derivatives with Antitumor Activity

    Directory of Open Access Journals (Sweden)

    Rafat M. Mohareb

    2010-12-01

    Full Text Available The reaction of cyanoacetyl hydrazine (1 with 3-acetylpyridine (2 gave the hydrazide-hydrazone derivative 3. The latter compound undergoes a series of heterocyclization reactions to give new heterocyclic compounds. The antitumor evaluation of the newly synthesized products against three cancer cell lines, namely breast adenocarcinoma (MCF-7, non-small cell lung cancer (NCI-H460 and CNS cancer (SF-268 was performed. Most of the synthesized compounds showed high inhibitory effects.

  15. Novel Synthesis of Hydrazide-Hydrazone Derivatives and Their Utilization in the Synthesis of Coumarin, Pyridine, Thiazole and Thiophene Derivatives with Antitumor Activity

    OpenAIRE

    Rafat M. Mohareb; Ola K. Sakka; Daisy H. Fleita

    2010-01-01

    The reaction of cyanoacetyl hydrazine (1) with 3-acetylpyridine (2) gave the hydrazide-hydrazone derivative 3. The latter compound undergoes a series of heterocyclization reactions to give new heterocyclic compounds. The antitumor evaluation of the newly synthesized products against three cancer cell lines, namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) was performed. Most of the synthesized compounds showed high inhibitory effects.

  16. Novel synthesis of hydrazide-hydrazone derivatives and their utilization in the synthesis of coumarin, pyridine, thiazole and thiophene derivatives with antitumor activity.

    Science.gov (United States)

    Mohareb, Rafat M; Fleita, Daisy H; Sakka, Ola K

    2010-12-23

    The reaction of cyanoacetyl hydrazine (1) with 3-acetylpyridine (2) gave the hydrazide-hydrazone derivative 3. The latter compound undergoes a series of heterocyclization reactions to give new heterocyclic compounds. The antitumor evaluation of the newly synthesized products against three cancer cell lines, namely breast adenocarcinoma (MCF-7), non-small cell lung cancer (NCI-H460) and CNS cancer (SF-268) was performed. Most of the synthesized compounds showed high inhibitory effects.

  17. A green chemistry approach for synthesizing biocompatible gold nanoparticles

    Science.gov (United States)

    Gurunathan, Sangiliyandi; Han, JaeWoong; Park, Jung Hyun; Kim, Jin-Hoi

    2014-05-01

    Gold nanoparticles (AuNPs) are a fascinating class of nanomaterial that can be used for a wide range of biomedical applications, including bio-imaging, lateral flow assays, environmental detection and purification, data storage, drug delivery, biomarkers, catalysis, chemical sensors, and DNA detection. Biological synthesis of nanoparticles appears to be simple, cost-effective, non-toxic, and easy to use for controlling size, shape, and stability, which is unlike the chemically synthesized nanoparticles. The aim of this study was to synthesize homogeneous AuNPs using pharmaceutically important Ganoderma spp . We developed a simple, non-toxic, and green method for water-soluble AuNP synthesis by treating gold (III) chloride trihydrate (HAuCl4) with a hot aqueous extract of the Ganoderma spp . mycelia. The formation of biologically synthesized AuNPs (bio-AuNPs) was characterized by ultraviolet (UV)-visible absorption spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray (EDX), dynamic light scattering (DLS), and transmission electron microscopy (TEM). Furthermore, the biocompatibility of as-prepared AuNPs was evaluated using a series of assays, such as cell viability, lactate dehydrogenase leakage, and reactive oxygen species generation (ROS) in human breast cancer cells (MDA-MB-231). The color change of the solution from yellow to reddish pink and strong surface plasmon resonance were observed at 520 nm using UV-visible spectroscopy, and that indicated the formation of AuNPs. DLS analysis revealed the size distribution of AuNPs in liquid solution, and the average size of AuNPs was 20 nm. The size and morphology of AuNPs were investigated using TEM. The biocompatibility effect of as-prepared AuNPs was investigated in MDA-MB-231 breast cancer cells by using various concentrations of AuNPs (10 to 100 μM) for 24 h. Our findings suggest that AuNPs are non-cytotoxic and biocompatible. To the best of our knowledge

  18. A green chemistry approach for synthesizing biocompatible gold nanoparticles.

    Science.gov (United States)

    Gurunathan, Sangiliyandi; Han, JaeWoong; Park, Jung Hyun; Kim, Jin-Hoi

    2014-01-01

    Gold nanoparticles (AuNPs) are a fascinating class of nanomaterial that can be used for a wide range of biomedical applications, including bio-imaging, lateral flow assays, environmental detection and purification, data storage, drug delivery, biomarkers, catalysis, chemical sensors, and DNA detection. Biological synthesis of nanoparticles appears to be simple, cost-effective, non-toxic, and easy to use for controlling size, shape, and stability, which is unlike the chemically synthesized nanoparticles. The aim of this study was to synthesize homogeneous AuNPs using pharmaceutically important Ganoderma spp. We developed a simple, non-toxic, and green method for water-soluble AuNP synthesis by treating gold (III) chloride trihydrate (HAuCl4) with a hot aqueous extract of the Ganoderma spp. mycelia. The formation of biologically synthesized AuNPs (bio-AuNPs) was characterized by ultraviolet (UV)-visible absorption spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray (EDX), dynamic light scattering (DLS), and transmission electron microscopy (TEM). Furthermore, the biocompatibility of as-prepared AuNPs was evaluated using a series of assays, such as cell viability, lactate dehydrogenase leakage, and reactive oxygen species generation (ROS) in human breast cancer cells (MDA-MB-231). The color change of the solution from yellow to reddish pink and strong surface plasmon resonance were observed at 520 nm using UV-visible spectroscopy, and that indicated the formation of AuNPs. DLS analysis revealed the size distribution of AuNPs in liquid solution, and the average size of AuNPs was 20 nm. The size and morphology of AuNPs were investigated using TEM. The biocompatibility effect of as-prepared AuNPs was investigated in MDA-MB-231 breast cancer cells by using various concentrations of AuNPs (10 to 100 μM) for 24 h. Our findings suggest that AuNPs are non-cytotoxic and biocompatible. To the best of our knowledge

  19. Synthesis and antifungal activities of pradimicin derivatives, modification at C4'-position.

    Science.gov (United States)

    Kamachi, H; Iimura, S; Okuyama, S; Hoshi, H; Tamura, S; Shinoda, M; Saitoh, K; Konishi, M; Oki, T

    1992-09-01

    The 4'-N-alkyl(1 approximately 10) and 4'-N-acyl derivatives (11 approximately 21) of pradimicins (PRMs) were synthesized by trimethylsilylation of PRMs A, C and FA-1 followed by condensation with appropriate alkylating and acylating agents. The 4'-hydroxy derivatives (23 and 24) were synthesized from PRM FA-2 in a 3-step sequence. Among these compounds, the 4'-N-carboxyl substituted alkyl (1, 5, 8 and 10), 4'-N-formyl (11) and 4'-axial-hydroxy (23) derivatives retained the antifungal activity of the parent compounds and showed great improvement in water solubility.

  20. Synthesis of nanodispersible 6-aryl-2,4-diamino-1,3,5-triazine and its derivatives

    International Nuclear Information System (INIS)

    Padalkar, Vikas S.; Patil, Vikas S.; Phatangare, Kiran R.; Gupta, Vinod D.; Umape, Prashant G.; Sekar, N.

    2010-01-01

    A series of novel branched derivatives of 6-aryl-2,4-diamino-1,3,5-triazine from corresponding aryl nitriles and dicyanodiamide was synthesized. These compounds show a nanodispersibility and good thermal stability.

  1. Meta-analysis in plant pathology: synthesizing research results.

    Science.gov (United States)

    Rosenberg, M S; Garrett, K A; Su, Z; Bowden, R L

    2004-09-01

    ABSTRACT Meta-analysis is a set of statistical procedures for synthesizing research results from a number of different studies. An estimate of a statistical effect, such as the difference in disease severity for plants with or without a management treatment, is collected from each study along with a measure of the variance of the estimate of the effect. Combining results from different studies will generally result in increased statistical power so that it is easier to detect small effects. Combining results from different studies may also make it possible to compare the size of the effect as a function of other predictor variables such as geographic region or pathogen species. We present a review of the basic methodology for meta-analysis. We also present an example of meta-analysis of the relationship between disease severity and yield loss for foliar wheat diseases, based on data collected from a decade of fungicide and nematicide test results.

  2. Electrochemically synthesized stretchable polypyrrole/fabric electrodes for supercapacitor

    International Nuclear Information System (INIS)

    Yue, Binbin; Wang, Caiyun; Ding, Xin; Wallace, Gordon G.

    2013-01-01

    Wearable electronics offer the combined advantages of both electronics and fabrics. Being an indispensable part of these electronics, lightweight, stretchable and wearable power sources are strongly demanded. Here we describe a daily-used cotton fabric coated with polypyrrole as electrode for stretchable supercapacitors. Polypyrrole was synthesized on the Au coated fabric via an electrochemical polymerization process with p-toluenesulfonic acid (p-TS) as dopant from acetonitrile solution. This material was characterized with FESEM, tensile stress, and studied as a supercapacitor electrode in 1.0 M NaCl. This conductive textile electrode can sustain up to 140% strain without electric failure. It delivers a high specific capacitance of 254.9 F g −1 at a scan rate of 10 mV s −1 , and keeps almost unchanged at an applied strain (i.e. 30% and 50%) but with an improved cycling stability

  3. Method for synthesizing metal bis(borano) hypophosphite complexes

    Science.gov (United States)

    Cordaro, Joseph G.

    2013-06-18

    The present invention describes the synthesis of a family of metal bis(borano) hypophosphite complexes. One procedure described in detail is the syntheses of complexes beginning from phosphorus trichloride and sodium borohydride. Temperature, solvent, concentration, and atmosphere are all critical to ensure product formation. In the case of sodium bis(borano) hypophosphite, hydrogen gas was evolved upon heating at temperatures above 150.degree. C. Included in this family of materials are the salts of the alkali metals Li, Na and K, and those of the alkaline earth metals Mg and Ca. Hydrogen storage materials are possible. In particular the lithium salt, Li[PH.sub.2(BH.sub.3).sub.2], theoretically would contain nearly 12 wt % hydrogen. Analytical data for product characterization and thermal properties are given.

  4. Electrospray deposition of isolated chemically synthesized magnetic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Agostini, Pierre; Meffre, Anca; Lacroix, Lise-Marie; Ugnati, Damien [Université de Toulouse (France); INSA, UPS, CNRS, Laboratoire de Physique et Chimie des Nano-objets (LPCNO) (France); Ondarçuhu, Thierry [Centre d’Elaboration de Matériaux et d’Etudes Structurales (CEMES-CNRS) (France); Respaud, Marc; Lassagne, Benjamin, E-mail: lassagne@insa-toulouse.fr [Université de Toulouse (France); INSA, UPS, CNRS, Laboratoire de Physique et Chimie des Nano-objets (LPCNO) (France)

    2016-01-15

    The deposition of isolated magnetic nanoparticles onto a substrate was performed using electrohydrodynamic spraying. Two kinds of nanoparticles were sprayed, 11 nm CoFe carbide nanospheres and 10.5 nm Fe nanocubes. By studying carefully the evolution of the sprayed charged droplets and the mechanism of nanoparticle dispersion in them, we could optimize the nanoparticle concentration within the initial nanoparticle solution (i) to reduce the magnetic interaction and therefore prevent agglomeration and (ii) to obtain in a relatively short period (1 h) a deposit of isolated magnetic nanoparticles with a density of up to 400 nanoparticles per µm{sup 2}. These results open great perspectives for magnetic measurements on single objects using advanced magnetometry techniques as long as spintronics applications based on single chemically synthesized magnetic nanoparticles.

  5. Shape dependent heat transport through green synthesized gold nanofluids

    International Nuclear Information System (INIS)

    John, Jisha; Thomas, Lincy; Rajesh Kumar, B; Kurian, Achamma; George, Sajan D

    2015-01-01

    Nanofluids hold promise as a more efficient coolant for thermoelectric devices. Despite the capability of tailoring the thermo physical properties of nanofluids, by tuning the particle parameters such as shape, size and concentration, the toxicity of chemicals used for the preparation of nanoparticles is a serious concern. Green synthesis of nanoparticles is emerging as an alternative to the conventional chemical and physical methods for the preparation of nanoparticles. In this work, the results of the preparation of gold nanoparticles using plant extracts as reducing agents are presented. The green synthesis route employed for the present study provides particles of similar size, but the shape of the particles is found to vary depending upon the source of the natural reducing agents. The thermal diffusivity values of the gold nanofluid measured using laser based dual beam thermal lens technique elucidate the role of shape and concentration of the green synthesized nanoparticles on the effective thermal diffusivity values of the nanofluids. (paper)

  6. Planning chemical syntheses with deep neural networks and symbolic AI

    Science.gov (United States)

    Segler, Marwin H. S.; Preuss, Mike; Waller, Mark P.

    2018-03-01

    To plan the syntheses of small organic molecules, chemists use retrosynthesis, a problem-solving technique in which target molecules are recursively transformed into increasingly simpler precursors. Computer-aided retrosynthesis would be a valuable tool but at present it is slow and provides results of unsatisfactory quality. Here we use Monte Carlo tree search and symbolic artificial intelligence (AI) to discover retrosynthetic routes. We combined Monte Carlo tree search with an expansion policy network that guides the search, and a filter network to pre-select the most promising retrosynthetic steps. These deep neural networks were trained on essentially all reactions ever published in organic chemistry. Our system solves for almost twice as many molecules, thirty times faster than the traditional computer-aided search method, which is based on extracted rules and hand-designed heuristics. In a double-blind AB test, chemists on average considered our computer-generated routes to be equivalent to reported literature routes.

  7. Concrete embedded dye-synthesized photovoltaic solar cell.

    Science.gov (United States)

    Hosseini, T; Flores-Vivian, I; Sobolev, K; Kouklin, N

    2013-09-25

    This work presents the concept of a monolithic concrete-integrated dye-synthesized photovoltaic solar cell for optical-to-electrical energy conversion and on-site power generation. The transport measurements carried out in the dark revealed the presence of VOC of ~190 mV and ISC of ~9 μA, induced by the electrochemical conversion of concrete-supplied ionic impurities at the electrodes. The current-voltage measurements performed under illumination at incident optical powers of ~46 mW confirmed the generation of electrical power of ~0.64 μW with almost half generated via battery effect. This work presents a first step towards realizing the additional pathways to low-cost electrical power production in urban environments based on a combined use of organic dyes, nanotitania and concrete technology.

  8. Planning chemical syntheses with deep neural networks and symbolic AI.

    Science.gov (United States)

    Segler, Marwin H S; Preuss, Mike; Waller, Mark P

    2018-03-28

    To plan the syntheses of small organic molecules, chemists use retrosynthesis, a problem-solving technique in which target molecules are recursively transformed into increasingly simpler precursors. Computer-aided retrosynthesis would be a valuable tool but at present it is slow and provides results of unsatisfactory quality. Here we use Monte Carlo tree search and symbolic artificial intelligence (AI) to discover retrosynthetic routes. We combined Monte Carlo tree search with an expansion policy network that guides the search, and a filter network to pre-select the most promising retrosynthetic steps. These deep neural networks were trained on essentially all reactions ever published in organic chemistry. Our system solves for almost twice as many molecules, thirty times faster than the traditional computer-aided search method, which is based on extracted rules and hand-designed heuristics. In a double-blind AB test, chemists on average considered our computer-generated routes to be equivalent to reported literature routes.

  9. A facile route to synthesize nanogels doped with silver nanoparticles

    International Nuclear Information System (INIS)

    Coll Ferrer, M. Carme; Ferrier, Robert C.; Eckmann, David M.; Composto, Russell J.

    2013-01-01

    In this study, we describe a simple method to prepare hybrid nanogels consisting of a biocompatible core–shell polymer host containing silver nanoparticles. First, the nanogels (NG, ∼160 nm) containing a lysozyme rich core and a dextran rich shell, are prepared via Maillard and heat-gelation reactions. Second, silver nanoparticles (Ag NPs, ∼5 nm) are synthesized “in situ” in the NG solution without requiring additional reducing agents. This approach leads to stable Ag NPs located in the NG. Furthermore, we demonstrate that the amount of Ag NPs in the NG can be tuned by varying silver precursor concentration. Hybrid nanogels with silver nanoparticles have potential in antimicrobial, optical, and therapeutic applications.

  10. Kinetic aspects of the syntheses using short-lived radionuclides

    International Nuclear Information System (INIS)

    Laangstroem, B.; Obenius, U.; Sjoeberg, S.; Bergson, G.

    1981-01-01

    In syntheses using short-lived radionuclides, such as 11 C, the reaction conditions are usually such that the concentrations of the reactants, except for the labelled reactant, can be considered constant during the reaction. Two kinetic models have been investigated - irreversible and reversible bimolecular elementary reactions. The influence of the rate constants, of the equilibrium constants, and of the ratio between the starting reactants on the yield of the labelled product has been studied. The results show that, even in cases with unfavourable equilibrium constants, high yields of the labelled products can be obtained if the rate constant for the forward reaction is large. In addition, the specific activity of the labelled product as a function of time has been studied for the irreversible bimolecular case. (author)

  11. Ubiquitination of newly synthesized proteins at the ribosome.

    Science.gov (United States)

    Wang, Feng; Canadeo, Larissa A; Huibregtse, Jon M

    2015-07-01

    Newly synthesized proteins can be misfolded or damaged because of errors during synthesis or environmental insults (e.g., heat shock), placing a significant burden on protein quality control systems. In addition, numerous human diseases are associated with a deficiency in eliminating aberrant proteins or accumulation of aggregated proteins. Understanding the mechanisms of protein quality control and disposal pathways for misfolded proteins is therefore crucial for therapeutic intervention in these diseases. Quality control processes function at many points in the life cycle of proteins, and a subset act at the actual site of protein synthesis, the ribosome. Here we summarize recent advances in the role of the ubiquitin proteasome system in protein quality control during the process of translation. Copyright © 2015 Elsevier B.V. and Société française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  12. Bone sialoprotein II synthesized by cultured osteoblasts contains tyrosine sulfate

    International Nuclear Information System (INIS)

    Ecarot-Charrier, B.; Bouchard, F.; Delloye, C.

    1989-01-01

    Isolated mouse osteoblasts that retain their osteogenic activity in culture were incubated with [35S] sulfate. Two radiolabeled proteins, in addition to proteoglycans, were extracted from the calcified matrix of osteoblast cultures. All the sulfate label in both proteins was in the form of tyrosine sulfate as assessed by amino acid analysis and thin layer chromatography following alkaline hydrolysis. The elution behavior on DEAE-Sephacel of the major sulfated protein and the apparent Mr on sodium dodecyl sulfate gels were characteristic of bone sialoprotein II extracted from rat. This protein was shown to cross-react with an antiserum raised against bovine bone sialoprotein II, indicating that bone sialoprotein II synthesized by cultured mouse osteoblasts is a tyrosine-sulfated protein. The minor sulfated protein was tentatively identified as bone sialoprotein I or osteopontin based on its elution properties on DEAE-Sephacel and anomalous behavior on sodium dodecyl sulfate gels similar to those reported for rat bone sialoprotein I

  13. Porphyrin-Azobenzene-Bodipy Triads: Syntheses, Structures, and Photophysical Properties.

    Science.gov (United States)

    Yin, Bangshao; Kim, Taeyeon; Zhou, Mingbo; Huang, Weiming; Kim, Dongho; Song, Jianxin

    2017-05-19

    Cyclic and acyclic azobenzene bridged porphyrin-dipyrrin derivatives were successfully prepared via Suzuki-Miyaura coupling reaction of α,α'-diborylated dipyrromethane with bromoazophenyl porphyrin or reaction of borylated porphyrin with dibromoazophenyl dipyrrin, and the corresponding porphyrin-Bodipy derivatives were obtained by subsequent boron complexation. The cyclic porphyrin-dipyrrin compound 3Ni was confirmed by X-ray diffraction. The low fluorescence quantum yields of azobenzene bridged porphyrin-Bodipy can be ascribed to the presence of the intramolecular charge transfer state.

  14. Spectroscopic and molecular modeling investigation on the binding of a synthesized steroidal amide to protein

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Hua-xin, E-mail: h.x.zhang@yeah.net; Liu, E.

    2014-09-15

    Owing to the various valuable biological activities, steroidal amides have become a hot topic in steroidal pharmaceutical chemistry. In this paper, an anti-tumor steroid derivate (DAAO) was synthesized and identified. The interaction between DAAO and human serum albumin (HSA) was studied by fluorescence spectra, circular dichroism (CD) spectra, molecular modeling and molecular probe techniques. The results suggested that DAAO had reacted with HSA through hydrogen bonds and van der Waals power. The formation of DAAO–HSA complex at ground state led to static quenching of HSA's fluorescence. The number of binding sites, binding constants, enthalpy change (ΔH{sup θ}), Gibbs free energy change (ΔG{sup θ}) and entropy change (ΔS{sup θ}) were calculated at different temperatures based on fluorescence quenching theory and classic equation. Molecular modeling investigation indicated that DAAO was more inclined to absorb on Sudlow's site I in subdomain IIA of HSA molecule on grounds of the lowest energy principle and steric hindrance effect. The binding location was further confirmed by fluorescence probe experiment using warfarin (site I probe) for displacement. Furthermore, the conformational changes of HSA in presence of DAAO were investigated by CD spectra. The results could provide new evidence explaining the relationship between the chemical structure and biological activity and may be useful for understanding the anti-cancer mechanism of steroidal drug. - Highlights: • A designed steroidal amide compound (DAAO) was synthesized by introducing amido bonds into a steroid nucleus. • DAAO binds to Sudlow's site I in HSA through hydrogen bonds and van der Waals power. • The interaction was a spontaneous and exothermic process with modest degree of reversibility. • The secondary structure of HSA and the microenvironment of TRP214 altered. • Amido bond in steroid nucleus (–NH–CO–) plays important role in stabling the structure of

  15. Total Syntheses of Polycyclic Polyprenylated Acylphloroglucinol Natural Products and Analogs Utilizing Alkylative Dearomatizations and Cationic Cyclizations

    Science.gov (United States)

    Boyce, Jonathan H.

    Polycyclic polyprenylated acylphloroglucinols (PPAPs) are structurally complex natural products with promising biological activities. These compounds have interesting anticancer and anti-HIV properties as well as other biological activities making them highly attractive synthetic targets. We report a stereodivergent, asymmetric total synthesis of (-)-clusianone in six steps from commercial materials. We have implemented a challenging cationic cyclization forging a bond between two sterically encumbered quaternary carbon atoms. Mechanistic studies point to the unique ability of formic acid to mediate the cyclization forming the clusianone framework. We also present a biosynthesis-inspired, diversity-oriented synthesis approach for rapid construction of PPAP analogs via palladium-catalyzed dearomative conjunctive allylic alkylation (DCAA). These efficient palladium-catalyzed protocols construct the [3.3.1]-bicyclic PPAP core in a single step from their stable aromatic precursors. The first syntheses of 13,14-didehydroxyisogarcinol and garcimultiflorone A stereoisomers are reported in six steps from a commercially available phloroglucinol. Lewis acid-controlled, diastereoselective cationic oxycyclizations enabled asymmetric syntheses of (-)-6-epi-13,14-didehydroxyisogarcinol and (+)-30-epi-13,14-didehydroxyisogarcinol. A similar strategy enabled production of the meso-derived isomers (+/-)-6,30- epi-13,14-didehydroxyisogarcinol and (+/-)-6,30-epi -garcmultiflorone A. A convenient strategy for gram scale synthesis of these stereoisomers was developed utilizing diastereomer separation at a later stage in the synthesis that minimized the number of necessary synthetic operations to access all possible stereoisomers. Finally, we report cationic rearrangements of dearomatized acylphloroglucinols leading to the formation of unprecedented PPAP scaffolds. A novel type A [3.3.1]-bicyclic PPAP was produced as a major product and the structure confirmed by X-ray crystallographic

  16. Effects of Newly Synthesized DCP-LA-Phospholipids on Protein Kinase C and Protein Phosphatases

    Directory of Open Access Journals (Sweden)

    Takeshi Kanno

    2013-04-01

    Full Text Available Background/Aims: The linoleic acid derivative DCP-LA selectively activates PKCε and inhibits protein phosphatase 1 (PP1. In the present study, we have newly synthesized phosphatidyl-ethanolamine, -serine, -choline, and -inositol containing DCP-LA at the α and β position (diDCP-LA-PE, -PS, PC, and -PI, respectively, and examined the effects of these compounds on activities of PKC isozymes and protein phosphatases. Methods: Activities of PKC isozymes PKCα, -βΙ, -βΙΙ, -γ, -δ, -ε-, ι, and -ζ and protein phosphatases PP1, PP2A, and protein tyrosine phosphatase 1B (PTP1B were assayed under the cell-free conditions. Results: All the compounds activated PKC, with the different potential, but only PKCγ inhibition was obtained with diDCP-LA-PC. Of compounds diDCP-LA-PE alone significantly activated PKCι and -ζ. diDCP-LA-PE and diDCP-LA-PI suppressed PP1 activity, but otherwise diDCP-LA-PI enhanced PP2A activity. diDCP-LA-PE, diDCP-LA-PS, and diDCP-LA-PI strongly reduced PTP1B activity, while diDCP-LA-PC enhanced the activity. Conclusion: All the newly synthesized DCP-LA-phospholipids serve as a PKC activator and of them diDCP-LA-PE alone has the potential to activate the atypical PKC isozymes PKCι and -ζ. diDCP-LA-PE and diDCP-LA-PI serve as an inhibitor for PP1 and PTP1B, diDCP-LA-PS as a PTP1B inhibitor, diDCP-LA-PI as a PP2A enhancer, and diDCP-LA-PC as a PTP1B enhancer.

  17. Structural characterization of glucosylated lactose derivatives synthesized by the Lactobacillus reuteri GtfA and Gtf180 glucansucrase enzymes

    NARCIS (Netherlands)

    Pham, Hien T T; Dijkhuizen, Lubbert; van Leeuwen, Sander S

    2017-01-01

    Glucansucrase enzymes from lactic acid bacteria are receiving strong interest because of their wide range of gluco-oligosaccharide and polysaccharide products from sucrose, some of which have prebiotic potential. Glucansucrases GtfA and Gtf180 from Lactobacillus reuteri strains are known to convert

  18. Synthesis and Microbiological Activity of Some Newly Synthesized Derivatives of 2-Oxo-2H-chromen-2-one

    OpenAIRE

    Daci-Ajvazi, Majlinda; Govori, Sevdije; Omeragiq, Shuhreta

    2011-01-01

    By the action of 2-amino-5-methylthio-1,3,4-thiadiazole, 3-amino-5-methylisoxazole, 2-amino-6-fluorobenzothiazole, 2-amino-5-chloropyridine, respectively, on 4-chloro-2-oxo-2H-chromene-3-sulfonyl chloride, the corresponding 9-methylthio-7,7-dioxo-7,7a-dihydro-5-oxo-7λ6,10-dithia-8,11-diaza-cyclopenta[b] phenantren-6-one, 9-methyl-7,7-dioxo-7H-5,8-dioxa-7λ6-thia-7a,11-diaza-cyclopenta[b] phenantren-6-one, 9-fluoro-7,7-dioxo-7H-5-oxa-7λ6,12-dithia-7a,13-diaza-indeno[1,2-b] phenantren-6-one and ...

  19. Synthesis and Microbiological Activity of Some Newly Synthesized Derivatives of 2-Oxo-2H-chromen-2-one

    Directory of Open Access Journals (Sweden)

    Majlinda Daci-Ajvazi

    2011-01-01

    Full Text Available By the action of 2-amino-5-methylthio-1,3,4-thiadiazole, 3-amino-5-methylisoxazole, 2-amino-6-fluorobenzothiazole, 2-amino-5-chloropyridine, respectively, on 4-chloro-2-oxo-2H-chromene-3-sulfonyl chloride, the corresponding 9-methylthio-7,7-dioxo-7,7a-dihydro-5-oxo-7λ6,10-dithia-8,11-diaza-cyclopenta[b] phenantren-6-one, 9-methyl-7,7-dioxo-7H-5,8-dioxa-7λ6-thia-7a,11-diaza-cyclopenta[b] phenantren-6-one, 9-fluoro-7,7-dioxo-7H-5-oxa-7λ6,12-dithia-7a,13-diaza-indeno[1,2-b] phenantren-6-one and 9-Chloro-7,7-dioxo-7H-5-oxa-7λ6-thia-7a,12-diaza-benzo[α]anthracen -6-one were formed and they have been isolated in satisfying yields. Based on the biological activity of chromene-2-ones and heterocyclic compounds condensed in position 3 and 4, we also studied microbiological activity of these new compounds (5-8, against Staphylococcus aureus ATCC 25923, Streptococcus pneumoniae, Aeromonas Salmonicida, Bacillus spp and some of them exhibited significant activity.

  20. Establishing Derived Manding for Specific Amounts with Three Children: An Attempt at Synthesizing Skinner's "Verbal Behavior" with Relational Frame Theory

    Science.gov (United States)

    Murphy, Carol; Barnes-Holmes, Dermot

    2009-01-01

    Participants were 2 typically developing children, aged 9 and 10 years, and 1 child, aged 4 years, with a reported severe speech delay. Five specific mand functions were trained such that participants learned to mand for the delivery or removal of tokens to the value of -2, -1, 0, +1, and +2, by presenting an arbitrary stimulus (A1, A2, A3, A4,…

  1. γ-Irradiation and characterization of synthesized methoxybenzylpyrimidine formimidate Schiff-base and some metal-complex derivatives

    Directory of Open Access Journals (Sweden)

    R.O. Aly

    2016-09-01

    The magnetic properties together with the UV–Vis reposted data revealed the octahedral coordination of the Zn- and La-complex and the tetragonal distortion geometry of the Cu-complex. The La-complexes revealed only moderate inhibition against the Gram-negative Escherichia coli, whereas the Zn-complex revealed significant inhibition. The latter showed also similar effect against the Gram-positive Bacillus subtilis and Streptococcus pyogens (ATCC-19615.

  2. An optimization study for radioiodination of a new synthesized benzamide derivative as an analogue tracer for malignant melanoma imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kandil, Shaban A.; Aglan, Hany; Seddik, Usama [Atomic Energy Authority, Cairo (Egypt). Nuclear Research Center; EL-Kafrawy, Ahmed F. [Ain Shams Univ., Cairo (Egypt). Faculty of Science

    2017-03-01

    Iodobenzamides are reported to possess some affinity for melanoma. This study describes the synthesis of a new benzamide analogue, N-(2-diethylamino-ethyl)-4-(4-chloro-nicotinamido)-5-[{sup 125}I]iodo-2 -methoxybenz amide ([{sup 125}I]H4) designed to target melanoma. The synthesis was simply achieved in four steps. There were two PyCIU/DIPEA amide condensations and a transfer hydrogenation using an ammonium formate hydrogen donor. The radioiodination step was carried out with {sup 125}I via an electrophilic substitution reaction. The reaction conditions were optimized. The labeled compound was purified by HPLC. The maximum radiochemical yield was found to be 78% at a radiochemical purity of 98%. All compounds were characterized by MS and NMR techniques. The log P value for [{sup 125}I]H4 was found as 3.96±0.5.

  3. Why Does Synthesized Data Improve Multi-sequence Classification?

    NARCIS (Netherlands)

    G. van Tulder (Gijs); M. de Bruijne (Marleen)

    2015-01-01

    textabstractThe classification and registration of incomplete multi-modal medical images, such as multi-sequence MRI with missing sequences, can sometimes be improved by replacing the missing modalities with synthetic data. This may seem counter-intuitive: synthetic data is derived from data that is

  4. Cytotoxic effect of nanoparticles synthesized from Salvia officinalis L

    African Journals Online (AJOL)

    User

    2012-06-28

    Jun 28, 2012 ... The development of safe carriers for the use of plant extracts in industrial and health fields constitute a matter of serious concern. The development of plant derived nanoparticles may help to overcome such barriers. However, the major concern is still the safety of these carriers. The present study describes.

  5. Cytotoxic effect of nanoparticles synthesized from Salvia officinalis L ...

    African Journals Online (AJOL)

    The development of safe carriers for the use of plant extracts in industrial and health fields constitute a matter of serious concern. The development of plant derived nanoparticles may help to overcome such barriers. However, the major concern is still the safety of these carriers. The present study describes the synthesis of ...

  6. Camalexin is synthesized from indole-3-acetaldoxime, a key branching point between primary and secondary metabolism in Arabidopsis.

    Science.gov (United States)

    Glawischnig, Erich; Hansen, Bjarne Gram; Olsen, Carl Erik; Halkier, Barbara Ann

    2004-05-25

    Characteristic for cruciferous plants is their production of N- and S-containing indole phytoalexins with disease resistance and cancer-preventive properties, previously proposed to be synthesized from indole independently of tryptophan. We show that camalexin, the indole phytoalexin of Arabidopsis thaliana, is synthesized from tryptophan via indole-3-acetaldoxime (IAOx) in a reaction catalyzed by CYP79B2 and CYP79B3. Cyp79B2/cyp79B3 double knockout mutant is devoid of camalexin, as it is also devoid of indole glucosinolates [Zhao, Y., Hull, A. K., Gupta, N. R., Goss, K. A., Alonso, J., Ecker, J. R., Normanly, J., Chory, J. & Celenza, J. L. (2002) Genes Dev. 16, 3100-3112], and isotope-labeled IAOx is incorporated into camalexin. These results demonstrate that only CYP79B2 and CYP79B3 contribute significantly to the IAOx pool from which camalexin and indole glucosinolates are synthesized. Furthermore, production of camalexin in the sur1 mutant devoid of glucosinolates excludes the possibility that camalexin is derived from indole glucosinolates. CYP79B2 plays an important role in camalexin biosynthesis in that the transcript level of CYP79B2, but not CYP79B3, is increased upon induction of camalexin by silver nitrate as evidenced by microarray analysis and promoter-beta-glucuronidase data. The structural similarity between cruciferous indole phytoalexins suggests that these compounds are biogenetically related and synthesized from tryptophan via IAOx by CYP79B homologues. The data show that IAOx is a key branching point between several secondary metabolic pathways as well as primary metabolism, where IAOx has been shown to play a critical role in IAA homeostasis.

  7. Anti-Amoebic Properties of Carbonyl Thiourea Derivatives

    Directory of Open Access Journals (Sweden)

    Maizatul Akma Ibrahim

    2014-04-01

    Full Text Available Thiourea derivatives display a broad spectrum of applications in chemistry, various industries, medicines and various other fields. Recently, different thiourea derivatives have been synthesized and explored for their anti-microbial properties. In this study, four carbonyl thiourea derivatives were synthesized and characterized, and then further tested for their anti-amoebic properties on two potential pathogenic species of Acanthamoeba, namely A. castellanii (CCAP 1501/2A and A. polyphaga (CCAP 1501/3A. The results indicate that these newly-synthesized thiourea derivatives are active against both Acanthamoeba species. The IC50 values obtained were in the range of 2.39–8.77 µg·mL‑1 (9.47–30.46 µM for A. castellanii and 3.74–9.30 µg·mL‑1 (14.84–31.91 µM for A. polyphaga. Observations on the amoeba morphology indicated that the compounds caused the reduction of the amoeba size, shortening of their acanthopodia structures, and gave no distinct vacuolar and nuclear structures in the amoeba cells. Meanwhile, fluorescence microscopic observation using acridine orange and propidium iodide (AOPI staining revealed that the synthesized compounds induced compromised-membrane in the amoeba cells. The results of this study proved that these new carbonyl thiourea derivatives, especially compounds M1 and M2 provide potent cytotoxic properties toward pathogenic Acanthamoeba to suggest that they can be developed as new anti-amoebic agents for the treatment of Acanthamoeba keratitis.

  8. Synthesis and Biological Evaluation of Some Novel Dithiocarbamate Derivatives

    Directory of Open Access Journals (Sweden)

    Begüm Nurpelin Sağlık

    2014-01-01

    Full Text Available 18 novel dithiocarbamate derivatives were synthesized in order to investigate their inhibitory potency on acetylcholinesterase enzyme and antimicrobial activity. Structures of the synthesized compounds were elucidated by spectral data and elemental analyses. The synthesized compounds showed low enzyme inhibitory activity. However, they displayed good antimicrobial activity profile. Antibacterial activity of compounds 4a, 4e, and 4p (MIC = 25 μg/mL was equal to that of chloramphenicol against Klebsiella pneumoniae (ATCC 700603 and Escherichia coli (ATCC 35218. Most of the compounds exhibited notable antifungal activity against Candida albicans (ATCC 10231, Candida glabrata (ATCC 90030, Candida krusei (ATCC 6258, and Candida parapsilosis (ATCC 7330. Moreover, compound 4a, which carries piperidin-1-yl substituent and dimethylthiocarbamoyl side chain as variable group, showed twofold better anticandidal effect against all Candida species than reference drug ketoconazole.

  9. Higher derivative mimetic gravity

    Science.gov (United States)

    Gorji, Mohammad Ali; Mansoori, Seyed Ali Hosseini; Firouzjahi, Hassan

    2018-01-01

    We study cosmological perturbations in mimetic gravity in the presence of classified higher derivative terms which can make the mimetic perturbations stable. We show that the quadratic higher derivative terms which are independent of curvature and the cubic higher derivative terms which come from curvature corrections are sufficient to remove instabilities in mimetic perturbations. The classified higher derivative terms have the same dimensions but they contribute differently in the background and perturbed equations. Therefore, we can control both the background and the perturbation equations allowing us to construct the higher derivative extension of mimetic dark matter and the mimetic nonsingular bouncing scenarios. The latter can be thought as a new higher derivative effective action for the loop quantum cosmology scenario in which the equations of motion coincide with those suggested by loop quantum cosmology. We investigate a possible connection between the mimetic cosmology and the Randall-Sundrum cosmology.

  10. Taxation of Derivatives

    DEFF Research Database (Denmark)

    Dyppel, Katja Joo

    2013-01-01

    are known as futures, forwards, options and swaps. Derivatives are traded for the purpose of hedging financial or business risk, speculating in future spot prices and taking advantage of arbitrage opportunities. This market has increased tremendously in recent years. The term derivative is not used......The main objective for this thesis is to analyse and systematise the Danish legislation on taxation of derivatives. According to financial terminology, a derivative is a financial instrument. Its value is derived from changes in the value of one or more underlying assets.The most common derivatives...... in the Danish tax legislation. However, contracts known as forwards (terminskontrakter) and options (aftaler om køberetter og salgsretter) are generally included in the term financials contracts covered by the Danish Act on Taxation of Gains and Losses on Claims and Debt. The main part of the analysis deals...

  11. A synthesized biophysical and social vulnerability assessment for Taiwan

    Science.gov (United States)

    Lee, Yung-Jaan

    2017-11-01

    Taiwan, located in the Western Pacific, is a country that is one of the most vulnerable to disasters that are associated with the changing climate; it is located within the Ring of Fire, which is the most geologically active region in the world. The environmental and geological conditions in Taiwan are sensitive and vulnerable to such disasters. Owing to increasing urbanization in Taiwan, floods and climate-related disasters have taken an increasing toll on human lives. As global warming accelerates the rising of sea levels and increasing of the frequency of extreme weather events, disasters will continue to affect socioeconomic development and human conditions. Under such circumstances, researchers and policymakers alike must recognize the importance of providing useful knowledge concerning vulnerability, disaster recovery and resilience. Strategies for reducing vulnerability and climate-related disaster risks and for increasing resilience involve preparedness, mitigation and adaptation. In the last two decades, extreme climate events have caused severe flash floods, debris flows, landslides, and other disasters and have had negative effects of many sectors, including agriculture, infrastructure and health. Since climate change is expected to have a continued impact on socio-economic development, this work develops a vulnerability assessment framework that integrates both biophysical and social vulnerability and supports synthesized vulnerability analyses to identify vulnerable areas in Taiwan. Owing to its geographical, geological and climatic features, Taiwan is susceptible to earthquakes, typhoons, droughts and various induced disasters. Therefore, Taiwan has the urgent task of establishing a framework for assessing vulnerability as a planning and policy tool that can be used to identify not only the regions that require special attention but also hotspots in which efforts should be made to reduce vulnerability and the risk of climate-related disaster. To

  12. Global Derivatives Market

    Directory of Open Access Journals (Sweden)

    Stankovska Aleksandra

    2017-06-01

    Full Text Available Globalization of financial markets led to the enormous growth of volume and diversification of financial transactions. Financial derivatives were the basic elements of this growth. Derivatives play a useful and important role in hedging and risk management, but they also pose several dangers to the stability of financial markets and thereby the overall economy. Derivatives are used to hedge and speculate the risk associated with commerce and finance.

  13. Synthesis and Spectroscopic Studies ofAtenolol Derivatives with Enhanced Lipophilicity as Potential Prodrugs

    OpenAIRE

    Tabba, Hani D. [هاني الطباع وآخرون; Hassan, Mohamed A.; Hijawi, Ali S.; Voelter, Wolfgang

    2002-01-01

    Atenolol, a selective pi-adrenoceptor blocking agent is characterized by its low bioavailability. A number of atenolol prodrugs were synthesized to improve its lipid solubility and hence bioavailability. These compounds included an oxazolidine-2-thione derivative (II), a l,4-oxazine-2,3-dione derivative (III), and a series of oxazolidine derivatives (IVa-m). The structure of each compound was characterized by elemental analysis, infrared (IR), protonnuclear magnetic resonance ( H-NMR), and ma...

  14. Numerical derivation in optimization

    International Nuclear Information System (INIS)

    Abadie, J.; Salhi, Y.

    1988-01-01

    Newton's method for function minimization possesses an outstanding property. Its final quadratic convergence under very weak hypothesis, but also some drawbacks, among which (i) the possibility of non convergence when starting far from the solution sought and (ii) the necessity of computing (and then programming) the first and second partial derivatives. We show in this paper how to avoid both difficulties, assuming however that the first partial derivatives are computed by exact formulae. The second partial derivatives are computed by central differences of first derivatives. The difference step h is calculated so as to establish a trade-off between accuracy and computation speed. Encouraging numerical experiments support the proposed method [fr

  15. Syntheses of special monomers for .pi.-conjugated polymers

    Czech Academy of Sciences Publication Activity Database

    Výprachtický, Drahomír; Cimrová, Věra; Pavlačková, Petra; Kmínek, Ivan

    2008-01-01

    Roč. 268, č. 1 (2008), s. 120-124 ISSN 1022-1360. [Microsymposium on Advanced Polymer Materials for Photonics and Electronics /47./. Prague, 15.07.2007-19.07.2007] R&D Projects: GA AV ČR IAA4050409; GA MŠk(CZ) 1M06031 Institutional research plan: CEZ:AV0Z40500505 Keywords : activated ester * .beta.-diketone * Horner-Wadsworth-Emmons reaction * pyrene derivative Subject RIV: BM - Solid Matter Physics ; Magnetism

  16. Catalytically and biologically active silver nanoparticles synthesized using essential oil

    Science.gov (United States)

    Vilas, Vidya; Philip, Daizy; Mathew, Joseph

    2014-11-01

    There are numerous reports on phytosynthesis of silver nanoparticles and various phytochemicals are involved in the reduction and stabilization. Pure explicit phytosynthetic protocol for catalytically and biologically active silver nanoparticles is of importance as it is an environmentally benign green method. This paper reports the use of essential oil of Myristica fragrans enriched in terpenes and phenyl propenes in the reduction and stabilization. FTIR spectra of the essential oil and the synthesized biogenic silver nanoparticles are in accordance with the GC-MS spectral analysis reports. Nanosilver is initially characterized by an intense SPR band around 420 nm, followed by XRD and TEM analysis revealing the formation of 12-26 nm sized, highly pure, crystalline silver nanoparticles. Excellent catalytic and bioactive potential of the silver nanoparticles is due to the surface modification. The chemocatalytic potential of nanosilver is exhibited by the rapid reduction of the organic pollutant, para nitro phenol and by the degradation of the thiazine dye, methylene blue. Significant antibacterial activity of the silver colloid against Gram positive, Staphylococcus aureus (inhibition zone - 12 mm) and Gram negative, Escherichia coli (inhibition zone - 14 mm) is demonstrated by Agar-well diffusion method. Strong antioxidant activity of the biogenic silver nanoparticles is depicted through NO scavenging, hydrogen peroxide scavenging, reducing power, DPPH and total antioxidant activity assays.

  17. Characterization and Biocompatibility of ``Green'' Synthesized Silver Nanoparticles

    Science.gov (United States)

    Moulton, Michael; Kunzelman, Samantha; Braydich-Stolle, Laura; Nadagouda, M.; Varma, R.; Hussain, Saber

    2008-10-01

    With ever increasing emphasis on nanotechnology, silver nanoparticle are being considered for many antimicrobial needs ranging from catheter coatings, to burn wound bandages. Current synthesis methods for creating silver nanoparticles typically call for potentially hazardous chemicals, extreme heat, and produce environmentally dangerous byproducts. As a culture intent on reducing our carbon footprint on the earth, societies' focus has turned to ``green'' production capabilities. Therefore, if nanotechnology is to continue to grow at its current rate it is essential that novel ``green'' synthesis of nanoparticles becomes a reality. Furthermore, with the current and near-future applications of silver nanoparticles in biological systems it is imperative to fully analyze the potential toxic effects of these nanoparticles. In this study we have shown that by reducing silver nitrate in solutions of tea extract or epinephrine of varying concentrations spherical silver nanoparticle are formed. Furthermore, evaluation of mitochondrial function (MTS) and membrane integrity (LDH) in alveolar rat macrophages and human keratinocytes showed that these ``green'' synthesized silver nanoparticles were nontoxic.

  18. Metabolic fate of orally administered enzymatically synthesized glycogen in rats.

    Science.gov (United States)

    Furuyashiki, Takashi; Takata, Hiroki; Kojima, Iwao; Kuriki, Takashi; Fukuda, Itsuko; Ashida, Hitoshi

    2011-04-01

    We developed a new process for enzymatically synthesized glycogen (ESG), which is equivalent in physicochemical properties to natural-source glycogen (NSG) except its resistant property to degradation by α-amylase in vitro. In this study the metabolic fates of orally administered ESG in rats were investigated by a single oral administration test and a 2 week ingestion test. The glycemic index of ESG was 79. After the 2 week ingestion of ESG, the cecal content and production of short chain fatty acids were significantly increased, the pH value of cecal content was lowered, and the counts of Bifidobacterium and Lactobacillus in feces were significantly increased. Additionally, plasma levels of triacylglycerol and total cholesterol were significantly reduced by ESG. In contrast, NSG did not affect these parameters at all. The results collectively suggest that around 20% of orally administered ESG was transferred to the cecum in the form of polymer and assimilated into short chain fatty acids by microbiota and the polymer affected lipid metabolism.

  19. Structure and solution properties of enzymatically synthesized glycogen.

    Science.gov (United States)

    Kajiura, Hideki; Takata, Hiroki; Kuriki, Takashi; Kitamura, Shinichi

    2010-04-19

    Recently, a new enzymatic process for glycogen production was developed. In this process, short-chain amylose is used as a substrate for branching enzymes (BE, EC 2.4.1.18). The molecular weight of the enzymatically synthesized glycogen (ESG) depends on the size and concentration of the substrate. Structural and physicochemical properties of ESG were compared to those of natural source glycogen (NSG). The average chain length, interior chain length, and exterior chain length of ESG were 8.2-11.6, 2.0-3.3, and 4.2-7.6, respectively. These values were within the range of variation of NSG. The appearances of both ESG and NSG in solution were opalescent (milky white and slightly bluish). Furthermore, transmission electron microscopy and atomic force microscopy showed that ESG molecules formed spherical particles, and that there were no differences between ESG and NSG. Viscometric analyses also showed the spherical nature of both glycogens. When ESG and NSG were treated with pullulanase, a glucan-hydrolyzing enzyme known to degrade glycogen only on its surface portion, both glycogens were similarly degraded. These analyses revealed that ESG shares similar molecular shapes and surface properties with NSG. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  20. Intestinal Epithelial Cells Synthesize Glucocorticoids and Regulate T Cell Activation

    Science.gov (United States)

    Cima, Igor; Corazza, Nadia; Dick, Bernhard; Fuhrer, Andrea; Herren, Simon; Jakob, Sabine; Ayuni, Erick; Mueller, Christoph; Brunner, Thomas

    2004-01-01

    Glucocorticoids (GCs) are important steroid hormones with widespread activities in metabolism, development, and immune regulation. The adrenal glands are the major source of GCs and release these hormones in response to psychological and immunological stress. However, there is increasing evidence that GCs may also be synthesized by nonadrenal tissues. Here, we report that the intestinal mucosa expresses steroidogenic enzymes and releases the GC corticosterone in response to T cell activation. T cell activation causes an increase in the intestinal expression of the steroidogenic enzymes required for GC synthesis. In situ hybridization analysis revealed that these enzymes are confined to the crypt region of the intestinal epithelial layer. Surprisingly, in situ–produced GCs exhibit both an inhibitory and a costimulatory role on intestinal T cell activation. In the absence of intestinal GCs in vivo, activation by anti-CD3 injection resulted in reduced CD69 expression and interferon-γ production by intestinal T cells, whereas activation by viral infection led to increased T cell activation. We conclude that the intestinal mucosa is a potent source of immunoregulatory GCs. PMID:15596520

  1. Differential Transcriptome Analysis between Paulownia fortunei and Its Synthesized Autopolyploid

    Directory of Open Access Journals (Sweden)

    Xiaoshen Zhang

    2014-03-01

    Full Text Available Paulownia fortunei is an ecologically and economically important tree species that is widely used as timber and chemical pulp. Its autotetraploid, which carries a number of valuable traits, was successfully induced with colchicine. To identify differences in gene expression between P. fortunei and its synthesized autotetraploid, we performed transcriptome sequencing using an Illumina Genome Analyzer IIx (GAIIx. About 94.8 million reads were generated and assembled into 383,056 transcripts, including 18,984 transcripts with a complete open reading frame. A conducted Basic Local Alignment Search Tool (BLAST search indicated that 16,004 complete transcripts had significant hits in the National Center for Biotechnology Information (NCBI non-redundant database. The complete transcripts were given functional assignments using three public protein databases. One thousand one hundred fifty eight differentially expressed complete transcripts were screened through a digital abundance analysis, including transcripts involved in energy metabolism and epigenetic regulation. Finally, the expression levels of several transcripts were confirmed by quantitative real-time PCR. Our results suggested that polyploidization caused epigenetic-related changes, which subsequently resulted in gene expression variation between diploid and autotetraploid P. fortunei. This might be the main mechanism affected by the polyploidization. Our results represent an extensive survey of the P. fortunei transcriptome and will facilitate subsequent functional genomics research in P. fortunei. Moreover, the gene expression profiles of P. fortunei and its autopolyploid will provide a valuable resource for the study of polyploidization.

  2. IRBAS: An online database to collate, analyze, and synthesize ...

    Science.gov (United States)

    Key questions dominating contemporary ecological research and management concern interactions between biodiversity, ecosystem processes, and ecosystem services provision in the face of global change. This is particularly salient for freshwater biodiversity and in the context of river drying and flow‐regime change. Rivers that stop flowing and dry, herein intermittent rivers, are globally prevalent and dynamic ecosystems on which the body of research is expanding rapidly, consistent with the era of big data. However, the data encapsulated by this work remain largely fragmented, limiting our ability to answer the key questions beyond a case‐by‐case basis. To this end, the Intermittent River Biodiversity Analysis and Synthesis (IRBAS; http://irbas.cesab.org) project has collated, analyzed, and synthesized data from across the world on the biodiversity and environmental characteristics of intermittent rivers. The IRBAS database integrates and provides free access to these data, contributing to the growing, and global, knowledge base on these ubiquitous and important river systems, for both theoretical and applied advancement. The IRBAS database currently houses over 2000 data samples collected from six countries across three continents, primarily describing aquatic invertebrate taxa inhabiting intermittent rivers during flowing hydrological phases. As such, there is room to expand the biogeographic and taxonomic coverage, for example, through addition of data

  3. Of Syntheses and Surprises: Toward a Critical Integral Theory

    Directory of Open Access Journals (Sweden)

    Daniel Gustav Anderson

    2006-12-01

    Full Text Available The central concern of this article is how the search for formal structures with universal values functions ideologically, addressing Zizek’s claim that East-West syntheses may represent the dominant ideology par excellance of global capitalism. To this end, the article offers a Foucaultian genealogy of Integral theory, tracing its origins to the cultural and subjective contingencies of the British Empire, primarily in the work of Integral theory’s foundational thinker, Aurobindo Ghose. The article poses a primary critique of synthesis and evolution as mythological keys to Ultimate Reality which suggests that Zizek’s critique may have some validity, and offers the potential for a “critical integral theory” as an alternative. Situated in Deleuze and Guattari’s concept of becoming, and represented in the ideas and practices of a constellation of thinkers inclusive of Gurdjieff, Benjamin, and Trungpa, the article’s view of integration supports radical democracy as presented in the writings of Laclau and Mouffe as a model outcome for social and personal transformational practices.

  4. Of Syntheses and Surprises:Toward a Critical Integral Theory

    Directory of Open Access Journals (Sweden)

    Daniel Gustav Anderson

    2006-12-01

    Full Text Available The central concern of this article is how the search for formal structures with universal values functions ideologically, addressing Zizek’s claim that East-West syntheses may represent the dominant ideology par excellance of global capitalism. To this end, the article offers a Foucaultian genealogy of Integral theory, tracing its origins to the cultural and subjective contingencies of the British Empire, primarily in the work of Integral theory’s foundational thinker, Aurobindo Ghose. The article poses a primary critique of synthesis and evolution as mythological keys to Ultimate Reality which suggests that Zizek’s critique may have some validity, and offers the potential for a “critical integral theory” as an alternative. Situated in Deleuze and Guattari’s concept of becoming, and represented in the ideas and practices of a constellation of thinkers inclusive of Gurdjieff, Benjamin, and Trungpa, the article’s view of integration supports radical democracy as presented in the writings of Laclau and Mouffe as a model outcome for social and personal transformational practices.

  5. Two-Volt Josephson Arbitrary Waveform Synthesizer Using Wilkinson Dividers

    Science.gov (United States)

    Flowers-Jacobs, Nathan E.; Fox, Anna E.; Dresselhaus, Paul D.; Schwall, Robert E.; Benz, Samuel P.

    2016-01-01

    The root-mean-square (rms) output voltage of the NIST Josephson arbitrary waveform synthesizer (JAWS) has been doubled from 1 V to a record 2 V by combining two new 1 V chips on a cryocooler. This higher voltage will improve calibrations of ac thermal voltage converters and precision voltage measurements that require state-of-the-art quantum accuracy, stability, and signal-to-noise ratio. We achieved this increase in output voltage by using four on-chip Wilkinson dividers and eight inner-outer dc blocks, which enable biasing of eight Josephson junction (JJ) arrays with high-speed inputs from only four high-speed pulse generator channels. This approach halves the number of pulse generator channels required in future JAWS systems. We also implemented on-chip superconducting interconnects between JJ arrays, which reduces systematic errors and enables a new modular chip package. Finally, we demonstrate a new technique for measuring and visualizing the operating current range that reduces the measurement time by almost two orders of magnitude and reveals the relationship between distortion in the output spectrum and output pulse sequence errors. PMID:27453676

  6. Kombucha-synthesized bacterial cellulose: preparation, characterization, and biocompatibility evaluation.

    Science.gov (United States)

    Zhu, Changlai; Li, Feng; Zhou, Xinyang; Lin, Lin; Zhang, Tianyi

    2014-05-01

    Bacterial cellulose (BC) is a natural biomaterial with unique properties suitable for tissue engineering applications, but it has not yet been used for preparing nerve conduits to repair peripheral nerve injuries. The objectives of this study were to prepare and characterize the Kampuchea-synthesized bacterial cellulose (KBC) and further evaluate the biocompatibility of KBC with peripheral nerve cells and tissues in vitro and in vivo. KBC membranes were composed of interwoven ribbons of about 20-100 nm in width, and had a high purity and the same crystallinity as that of cellulose Iα. The results from light and scanning electron microscopy, MTT assay, flow cytometry, and RT-PCR indicated that no significant differences in the morphology and cell function were observed between Schwann cells (SCs) cultured on KBC membranes and glass slips. We also fabricated a nerve conduit using KBC, which was implanted into the spatium intermusculare of rats. At 1, 3, and 6 weeks post-implantation, clinical chemistry and histochemistry showed that there were no significant differences in blood counts, serum biochemical parameters, and tissue reactions between implanted rats and sham-operated rats. Collectively, our data indicated that KBC possessed good biocompatibility with primary cultured SCs and KBC did not exert hematological and histological toxic effects on nerve tissues in vivo. Copyright © 2013 Wiley Periodicals, Inc.

  7. Microreactors-A Powerful Tool to Synthesize Peroxycarboxylic Esters.

    Science.gov (United States)

    Illg, Tobias; Knorr, Annett; Fritzsche, Lutz

    2015-12-22

    The synthesis of peroxycarboxylic esters, as one subgroup of organic peroxides, is characterized by a high thermal hazard potential regarding process safety. In case of failure in the production process, e.g., if the heat of reaction cannot be removed sufficiently fast, decomposition reactions can be triggered, and as a result, remarkable amounts of heat and gas can be released and can cause a high extent of damage. Multifarious technical and organizational measures are necessary to ensure the safe industrial production of peroxides. With the introduction of microreaction technology plenty of possibilities have been opened to carry out highly exothermic reactions in smaller volumes and with more efficient heat removal. In this paper we report the application of three different microstructured reactors, representing different mixing strategies, to synthesize two peroxymonocarboxylic esters, namely tert-butyl peroxypivalate and tert-butyl peroxy-2-ethylhexanoate. The following reactor types were considered: an orifice microreactor, a split and recombine microreactor and a capillary tube reactor in combination with ultrasonication. The efficiency of the two phase liquid/liquid reaction is expressed in comparison of conversion and selectivity. With microreaction technology a remarkable increase in space-time-yield, ranging from 12,500 kg·m(-3)·h(-1) to 414,000 kg·m(-3)·h(-1), is achieved.

  8. Microreactors—A Powerful Tool to Synthesize Peroxycarboxylic Esters

    Directory of Open Access Journals (Sweden)

    Tobias Illg

    2015-12-01

    Full Text Available The synthesis of peroxycarboxylic esters, as one subgroup of organic peroxides, is characterized by a high thermal hazard potential regarding process safety. In case of failure in the production process, e.g., if the heat of reaction cannot be removed sufficiently fast, decomposition reactions can be triggered, and as a result, remarkable amounts of heat and gas can be released and can cause a high extent of damage. Multifarious technical and organizational measures are necessary to ensure the safe industrial production of peroxides. With the introduction of microreaction technology plenty of possibilities have been opened to carry out highly exothermic reactions in smaller volumes and with more efficient heat removal. In this paper we report the application of three different microstructured reactors, representing different mixing strategies, to synthesize two peroxymonocarboxylic esters, namely tert-butyl peroxypivalate and tert-butyl peroxy-2-ethylhexanoate. The following reactor types were considered: an orifice microreactor, a split and recombine microreactor and a capillary tube reactor in combination with ultrasonication. The efficiency of the two phase liquid/liquid reaction is expressed in comparison of conversion and selectivity. With microreaction technology a remarkable increase in space-time-yield, ranging from 12,500 kg·m−3·h−1 to 414,000 kg·m−3·h−1, is achieved.

  9. [Effect of sleep on cerebral DNA synthesized during learning].

    Science.gov (United States)

    Ambrosini, M V; Scaroni, R; Chiurulla, C; Giuditta, A

    1984-03-30

    Female Wistar rats weighing 200 g were implanted with cortical electrodes and with an intraventricular cannula. Five days later they were injected with 3H-thymidine and subjected to a two-way active avoidance session lasting four hours. During the following three hours they were left free to sleep while their EEG activity was being recorded. Biochemical analyses carried out in different brain regions and in liver indicated that the concentration of cerebral radioactive DNA was markedly lower in non-learning rats as compared to learning animal and to the control group. An increase in synchronized sleep and in paradoxical sleep was observed in learning animals, whereas non-learning rats exhibited an increment of synchronized sleep only. On the basis of these results and of previous data obtained with rats analyzed soon after the training session, it is concluded that the effect observed in non-learning animals stems from a loss of radioactive DNA synthesized during training. Such a loss takes place in the following resting period and is to be related to the variations of sleep pattern recorded. The process of DNA degradation might reflect the elimination of molecules associated with neural information non longer usable for adaptive aims.

  10. Characterization of carbon cryogels synthesized by sol-gel polycondensation

    Directory of Open Access Journals (Sweden)

    BILJANA BABIC

    2005-02-01

    Full Text Available Resorcinol-formaldehyde (RF cryogels were synthesized by the sol-gel polycondensation of resorcinol (R with formaldehyde (F and freeze-drying was carried out with t-butanol. Carbon cryogels were obtained by pyrolyzing RF cryogels in an inert atmosphere. Characterization by nitrogen adsorption showed that the carbon cryogels were micro and mesoporous materials with high specific surface areas (SBET ~ 550 m2/g. Cyclic voltammetry experiments at various scan rates (2 to 200 mV s-1 were performed to study the electrical double-layer charging of carbon cryogel electrodes in 0.5 mol dm-3 HClO4 solution. It has been demonstrated that it is possible to sub-divide the total specific capacitance into the mesoporous and the microporous specific capacitance by analyzing the linear dependence of the charge (q on the reciprocal of the square root of the potential scan rate (v-1/2, and the linear dependence of the reciprocal charge (1/q on the square root of the potential scan rate (v-1/2. The specific capacitance was found to be constant over a wide range of sample weight (12.5 to 50.0 mg and a very promising specific capacitance value of 150 F/g, was found for this material operating in an acidic 0.5 mol dm-3 HClO4 solution at room temperature.

  11. Liquid-phase syntheses of cobalt ferrite nanoparticles

    Science.gov (United States)

    Sinkó, Katalin; Manek, Enikő; Meiszterics, Anikó; Havancsák, Károly; Vainio, Ulla; Peterlik, Herwig

    2012-06-01

    The aim of the present study was to synthesize cobalt-ferrite (CoFe2O4) nanoparticles using various liquid phase methods; sol-gel route, co-precipitation process, and microemulsion technique. The effects of experimental parameters on the particle size, size distribution, morphology, and chemical composition have been studied. The anions of precursors (chloride and nitrate), the solvents (water, n-propanol, ethanol, and benzyl alcohol), the precipitating agent (ammonia, sodium carbonate, and oxalic acid), the surfactants (polydimethylsiloxane, ethyl acetate, citric acid, cethyltrimethylammonium bromide, and sodium dodecil sulfate), their concentrations, and heat treatments were varied in the experiments. The smallest particles (around 40 nm) with narrow polydispersity and spherical shape could be achieved by a simple, fast sol-gel technique in the medium of propanol and ethyl acetate. The size characterization methods have also been investigated. Small-angle X-ray scattering (SAXS), dynamic light scattering (DLS), and scanning electron microscopy (SEM) provide the comparison of methods. The SAXS data correspond with the sizes detected by SEM and differ from DLS data. The crystalline phases, morphology, and chemical composition of the particles with different shapes have been analyzed by X-ray diffraction, SEM, and energy dispersive X-ray spectrometer.

  12. Evaluation of cytotoxicity of polypyrrole nanoparticles synthesized by oxidative polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Vaitkuviene, Aida [Department of Physical Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius (Lithuania); Department of Stem Cell Biology, State Research Institute Center for Innovative Medicine, Zygimantu 9, LT-01102 Vilnius (Lithuania); Kaseta, Vytautas [Department of Stem Cell Biology, State Research Institute Center for Innovative Medicine, Zygimantu 9, LT-01102 Vilnius (Lithuania); Voronovic, Jaroslav [Department of Physical Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius (Lithuania); Ramanauskaite, Giedre; Biziuleviciene, Gene [Department of Stem Cell Biology, State Research Institute Center for Innovative Medicine, Zygimantu 9, LT-01102 Vilnius (Lithuania); Ramanaviciene, Almira [NanoTechnas–Center of Nanotechnology and Material Science at Department of Analytical and Environmental Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, 03225 Vilnius (Lithuania); Ramanavicius, Arunas, E-mail: Arunas.Ramanavicius@chf.vu.lt [Department of Physical Chemistry, Faculty of Chemistry, Vilnius University, Naugarduko 24, LT-03225 Vilnius (Lithuania); Laboratory of BioNanoTechnology, Department of Materials Science and Electronics, Institute of Semiconductor Physics, State Scientific Research Institute Centre for Physical Sciences and Technology, A. Gostauto 11, LT-01108 Vilnius (Lithuania)

    2013-04-15

    Highlights: ► Polypyrrole nanoparticles synthesized by environmentally friendly polymerization at high concentrations are cytotoxic. ► Primary mouse embryonic fibroblast, mouse hepatoma and human T lymphocyte Jurkat cell lines were treated by Ppy nanoparticles. ► Polypyrrole nanoparticles at high concentrations inhibit cell proliferation. -- Abstract: Polypyrrole (Ppy) is known as biocompatible material, which is used in some diverse biomedical applications and seeming to be a very promising for advanced biotechnological applications. In order to increase our understanding about biocompatibility of Ppy, in this study pure Ppy nanoparticles (Ppy-NPs) of fixed size and morphology were prepared by one-step oxidative polymerization and their cyto-compatibility was evaluated. The impact of different concentration of Ppy nanoparticles on primary mouse embryonic fibroblasts (MEF), mouse hepatoma cell line (MH-22A), and human T lymphocyte Jurkat cell line was investigated. Cell morphology, viability/proliferation after the treatment by Ppy nanoparticles was evaluated. Obtained results showed that Ppy nanoparticles at low concentrations are biocompatible, while at high concentrations they became cytotoxic for Jurkat, MEF and MH-22A cells, and it was found that cytotoxic effect is dose-dependent.

  13. Tools to synthesize the learning of thin films

    International Nuclear Information System (INIS)

    Rojas, Roberto; Fuster, Gonzalo; Sluesarenko, Viktor

    2011-01-01

    After a review of textbooks written for undergraduate courses in physics, we have found that discussions on thin films are mostly incomplete. They consider the reflected and not the transmitted light for two instead of the four types of thin films. In this work, we complement the discussion in elementary textbooks, by analysing the phase differences required to match the conditions for constructive and destructive interference, in the reflected and transmitted light in four types of thin films. We consider thin films with varied sequences in the refractive index, which we identify as barriers, wells and stairs (up and down). Also, we use the conservation of energy in order to understand the complementary colour fringes observed in the reflected and transmitted light through thin films. We analyse systematically the phase changes by introducing a phase table and we synthesize the results in a circular diagram matching 16 physical situations of interference and their corresponding conditions on the film thickness. The phase table and the circular diagram are a pair of tools easily assimilated by students, and useful to organize, analyse and activate the knowledge about thin films.

  14. Conceptualizing and measuring energy security: A synthesized approach

    International Nuclear Information System (INIS)

    Sovacool, Benjamin K.; Mukherjee, Ishani

    2011-01-01

    This article provides a synthesized, workable framework for analyzing national energy security policies and performance. Drawn from research interviews, survey results, a focused workshop, and an extensive literature review, this article proposes that energy security ought to be comprised of five dimensions related to availability, affordability, technology development, sustainability, and regulation. We then break these five dimensions down into 20 components related to security of supply and production, dependency, and diversification for availability; price stability, access and equity, decentralization, and low prices for affordability; innovation and research, safety and reliability, resilience, energy efficiency, and investment for technology development; land use, water, climate change, and air pollution for sustainability; and governance, trade, competition, and knowledge for sound regulation. Further still, our synthesis lists 320 simple indicators and 52 complex indicators that policymakers and scholars can use to analyze, measure, track, and compare national performance on energy security. The article concludes by offering implications for energy policy more broadly. -- Highlights: → Energy security should consist of five dimensions related to availability, affordability, technology development, sustainability, and regulation. → The dimensions of energy security can be broken down into 20 components. → These components can be distilled into 320 simple indicators and 52 complex indicators.

  15. Synthesizing Econometric Evidence: The Case of Demand Elasticity Estimates.

    Science.gov (United States)

    DeCicca, Philip; Kenkel, Don

    2015-06-01

    Econometric estimates of the responsiveness of health-related consumer demand to higher prices are often key ingredients for risk policy analysis. We review the potential advantages and challenges of synthesizing econometric evidence on the price-responsiveness of consumer demand. We draw on examples of research on consumer demand for health-related goods, especially cigarettes. We argue that the overarching goal of research synthesis in this context is to provide policy-relevant evidence for broad-brush conclusions. We propose three main criteria to select among research synthesis methods. We discuss how in principle and in current practice synthesis of research on the price-elasticity of smoking meets our proposed criteria. Our analysis of current practice also contributes to academic research on the specific policy question of the effectiveness of higher cigarette prices to reduce smoking. Although we point out challenges and limitations, we believe more work on research synthesis in this area will be productive and important. © 2015 Society for Risk Analysis.

  16. Characterization of silver nanoparticles synthesized on titanium dioxide fine particles

    International Nuclear Information System (INIS)

    Nino-Martinez, N; Martinez-Castanon, G A; Aragon-Pina, A; Martinez-Gutierrez, F; Martinez-Mendoza, J R; Ruiz, Facundo

    2008-01-01

    Silver nanoparticles with a narrow size distribution were synthesized over the surface of two different commercial TiO 2 particles using a simple aqueous reduction method. The reducing agent used was NaBH 4 ; different molar ratios TiO 2 :Ag were also used. The nanocomposites thus prepared were characterized using transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), x-ray photoelectron spectroscopy (XPS), x-ray diffraction (XRD), dynamic light scattering (DLS) and UV-visible (UV-vis) absorption spectroscopy; the antibacterial activity was assessed using the standard microdilution method, determining the minimum inhibitory concentration (MIC) according to the National Committee for Clinical Laboratory Standards. From the microscopy studies (TEM and STEM) we observed that the silver nanoparticles are homogeneously distributed over the surface of TiO 2 particles and that the TiO 2 :Ag molar ratio plays an important role. We used three different TiO 2 Ag molar ratios and the size of the silver nanoparticles is 10, 20 and 80 nm, respectively. It was found that the antibacterial activity of the nanocomposites increases considerably comparing with separated silver nanoparticles and TiO 2 particles

  17. Promotion of hair growth by newly synthesized ceramide mimetic compound.

    Science.gov (United States)

    Park, Bu-Mahn; Bak, Soon-Sun; Shin, Kyung-Oh; Kim, Minhee; Kim, Daehwan; Jung, Sang-Hun; Jeong, Sekyoo; Sung, Young Kwan; Kim, Hyun Jung

    2017-09-09

    Based on the crucial roles of ceramides in skin barrier function, use of ceramides or their structural mimetic compounds, pseudoceramides, as cosmetic ingredients are getting more popular. While currently used pseudoceramides are intended to substitute the structural roles of ceramides in stratum corneum, development of bioactive pseudoceramides has been repeatedly reported. In this study, based on the potential involvement of sphingolipids in hair cycle regulation, we investigated the effects of newly synthesized pseudoceramide, bis-oleamido isopropyl alcohol (BOI), on hair growth using cultured human hair follicles and animal models. BOI treatment promoted hair growth in cultured human hair follicles ex vivo and induced earlier conversion of telogen into anagen. Although we did not find a significant enhancement of growth factor expression and follicular cell proliferation, BOI treatment resulted in an increased sphinganine and sphingosine contents as well as increased ceramides contents in cultured dermal papilla (DP) cells. Taken together, our data strongly suggest that biologically active pseudoceramide promotes hair growth by stimulating do novo synthesis of sphingolipids in DP cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Three pharmaceuticals cocrystals of adefovir: Syntheses, structures and dissolution study

    Science.gov (United States)

    Zhang, Xiaoming; Sun, Fuxing; Zhang, Tingting; Jia, Jiangtao; Su, Hongmin; Wang, Chenhui; Zhu, Guangshan

    2015-11-01

    We report here three novel cocrystals, which are composed of adefovir as the API (Active Pharmaceutical Ingredient) with p-aminobenzoic acid (1, 2C8H12N5O4P·C7H6NO2·3H2O), 3,5-dihydroxybenzoic acid (2, C8H12N5O4P·C7H6O4·H2O) and 2,6-pyridinedicarboxlic acid (3, C8H12N5O4P·C7H5NO4) as CCFs (cocrystal formers) respectively by crystal engineering strategy. Their structures were characterized by single crystal X-ray diffraction, powder X-ray diffraction (PXRD) analysis, thermogravimetric analyses (TGA), elemental analysis (EA) and infrared spectral analysis (IR). The analysis of single crystal X-ray diffraction demonstrate that cocrystal 1 and 2 form a strong hydrogen-bonded assembly through the phosphoric acids of API with water in the lattice and carboxylic acids of CCF respectively. Cocrystal 3 is formed in which the phosphoric acid groups of API are also held by the carboxylic acid groups of CCF. The PXRD results indicate their high purity of as-synthesized samples. The TGA, EA, IR and dissolution study of API and the cocrystals were also measured and discussed.

  19. Thermogravimetric study of vapor pressure of TATP synthesized without recrystallization.

    Science.gov (United States)

    Mbah, Jonathan; Knott, Debra; Steward, Scott

    2014-11-01

    This study aims at characterizing the vapor pressure signatures generated by triacetone triperoxide (TATP) that was synthesized without recrystallization by thermogravimmetric analysis (TGA) for exploitation by standoff detection technologies of explosive devices. The thermal behavior of the nonrecrystallized sample was compared with reported values. Any phase change, melting point and decomposition identification were studied by differential scanning calorimeter. Vapor pressures were estimated by the Langmuir method of evaporation from an open surface in a vacuum. Vapor pressures of TATP at different temperatures were calculated using the linear logarithmic relationship obtained from benzoic acid reference standard. Sublimation of TATP was found to follow apparent zero-order kinetics and sublimes at steady rates at 298 K and above. While the enthalpy of sublimation found, 71.7 kJ mol(-1), is in agreement with reported values the vapor pressures deviated significantly. The differences in the vapor pressures behavior are attributable to the synthesis pathway chosen in this study. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Reduction reactions applied for synthesizing different nano-structured materials

    Energy Technology Data Exchange (ETDEWEB)

    Albuquerque Brocchi, Eduardo de; Correia de Siqueira, Rogério Navarro [Department of Materials Engineering, PUC-Rio, Rua Marquês de São Vicente, 225, Gávea, 22453-900 Rio de Janeiro, RJ (Brazil); Motta, Marcelo Senna [Basck Ltd. (United Kingdom); Moura, Francisco José, E-mail: moura@puc-rio.br [Department of Materials Engineering, PUC-Rio, Rua Marquês de São Vicente, 225, Gávea, 22453-900 Rio de Janeiro, RJ (Brazil); Solórzano-Naranjo, Ivan Guillermo [Department of Materials Engineering, PUC-Rio, Rua Marquês de São Vicente, 225, Gávea, 22453-900 Rio de Janeiro, RJ (Brazil)

    2013-06-15

    Different materials have been synthesized by alternative routes: nitrates thermal decomposition to prepare oxide or co-formed oxides and reduction by hydrogen or graphite to obtain mixed oxides, composites or alloys. These chemical-based synthesis routes are described and thermodynamics studies and kinetics data are presented to support its feasibility. In addition, selective reduction reactions have been applied to successfully produce metal/ceramic composites, and alloys. Structural characterization has been carried out by X-ray Diffraction and, more extensively, Transmission Electron Microscopy operating in conventional diffraction contrast (CTEM) and high-resolution mode (HRTEM), indicated the possibility of obtaining oxide and alloy crystals of sizes ranging between 20 and 40 nm. - Highlights: • The viability in obtaining Ni–Co, Cu–Al, Mn–Al co-formed nano oxides was evaluated. • Partial and complete H{sub 2} reduction were used to produce alloy, composite and Spinel. • XRD, TEM and HREM techniques were used to characterize the obtained nanostructures.

  1. Antibacterial effect of bismuth subsalicylate nanoparticles synthesized by laser ablation

    Energy Technology Data Exchange (ETDEWEB)

    Flores-Castañeda, Mariela [Instituto Nacional de Investigaciones Nucleares (Mexico); Vega-Jiménez, Alejandro L., E-mail: argelia.almaguer@mac.com; Almaguer-Flores, Argelia [Universidad Nacional Autónoma de México, Facultad de Odontología, DEPeI, I (Mexico); Camps, Enrique; Pérez, Mario [Instituto Nacional de Investigaciones Nucleares (Mexico); Silva-Bermudez, Phaedra [Instituto Nacional de Rehabilitación, Unidad de Ingeniería de Tejidos, Terapia Celular y Medicina Regenerativa (Mexico); Berea, Edgardo [FarmaQuimia SA de CV. (Mexico); Rodil, Sandra E. [Universidad Nacional Autónoma de México, Instituto de Investigaciones en Materiales (Mexico)

    2015-11-15

    The antimicrobial properties of bismuth subsalicylate (BSS) nanoparticles against four opportunistic pathogens; E. coli, P. aeruginosa, S. aureus, and S. epidermidis were determined. BSS nanoparticles were synthesized by pulse laser ablation of a solid target in distilled water under different conditions. The nanoparticles were characterized using high-resolution transmission electron microscopy and absorption spectra and small angle X-ray scattering. The analysis shows that the colloids maintained the BSS structure and presented average particle size between 20 and 60 nm, while the concentration ranges from 95 to 195 mg/L. The antibacterial effect was reported as the inhibition ratio of the bacterial growth after 24 h and the cell viability was measured using the XTT assay. The results showed that the inhibition ratio of E. coli and S. epidermidis was dependant on the NPs size and/or concentration, meanwhile P. aeruginosa and S. aureus were more sensitive to the BSS nanoparticles independently of both the size and the concentration. In general, the BSS colloids with average particle size of 20 nm were the most effective, attaining inhibition ratios >80 %, similar or larger than those obtained with the antibiotic used as control. The results suggest that the BSS colloids could be used as effective antibacterial agents with potential applications in the medical area.

  2. Antibacterial effect of bismuth subsalicylate nanoparticles synthesized by laser ablation

    Science.gov (United States)

    Flores-Castañeda, Mariela; Vega-Jiménez, Alejandro L.; Almaguer-Flores, Argelia; Camps, Enrique; Pérez, Mario; Silva-Bermudez, Phaedra; Berea, Edgardo; Rodil, Sandra E.

    2015-11-01

    The antimicrobial properties of bismuth subsalicylate (BSS) nanoparticles against four opportunistic pathogens; E. coli, P. aeruginosa, S. aureus, and S. epidermidis were determined. BSS nanoparticles were synthesized by pulse laser ablation of a solid target in distilled water under different conditions. The nanoparticles were characterized using high-resolution transmission electron microscopy and absorption spectra and small angle X-ray scattering. The analysis shows that the colloids maintained the BSS structure and presented average particle size between 20 and 60 nm, while the concentration ranges from 95 to 195 mg/L. The antibacterial effect was reported as the inhibition ratio of the bacterial growth after 24 h and the cell viability was measured using the XTT assay. The results showed that the inhibition ratio of E. coli and S. epidermidis was dependant on the NPs size and/or concentration, meanwhile P. aeruginosa and S. aureus were more sensitive to the BSS nanoparticles independently of both the size and the concentration. In general, the BSS colloids with average particle size of 20 nm were the most effective, attaining inhibition ratios >80 %, similar or larger than those obtained with the antibiotic used as control. The results suggest that the BSS colloids could be used as effective antibacterial agents with potential applications in the medical area.

  3. Synthesis and standardization of biologically synthesized silver nanoparticles

    Science.gov (United States)

    Roy, Swarup; Das, Tapan Kumar

    2013-06-01

    The biological silver nanoparticle was synthesized extracellularly by using a fungi Aspergillus foetidus. The live cell filtrate of fungi has been used as reducing agent in the process of nanoparticles synthesis. In 50 ml cell filtrate a volume of AgNO3 stock solution was added to make finally the concentration as 1 mM of AgNO3 and allowed to shake in an incubator for several hrs in dark. The changed color was considered as the primary indication of nanoparticles formation and studies of UV-VIS, DLS, FTIR, AFM, TEM, EDS, Zeta pot. and nitrate reductase assay confirmed the same. It was indicated that stable & 20-40 nm roughly spherical shaped silver nanoparticles was formed. To standardize the nanoparticles biosynthesis different physical parameters like Substrate cone. (0-8 mM), PH-(5-12), Temp.-(5-50°C), incubation time (0-120) hrs and salinity (0.1-1.0 %) were investigated and it was observed that 4 mM AgNO3 conc., PH-9, Temp. -30°C, incubation time 72h and 0.2 % salinity were found to be optimum for the synthesis & stability of the silver nanoparticles.

  4. Synthesis, antimicrobial and cytotoxicity studies of some novel modified Strobilurin derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Sridhara, Ajjanna M.; Gopinath, Vadiraj S.; Bose, Prosenjit; Goud, Sanath Kumar [Advinus Therapeutics Pvt. Ltd., Bangalore (India); Reddy, Kallam R. Venugopala, E-mail: venurashmi30@rediffmail.co [Advinus Therapeutics Pvt. Ltd., Bangalore (India). Dept. of Studies in Industrial Chemistry; Keshavayya, Jathi [Advinus Therapeutics Pvt. Ltd., Bangalore (India). Dept. of Studies in Chemistry; Ambika, Dasannana Malige S. [Kuvempu University, Jnana Sahyadri, Karnataka (India). Dept. of Biochemistry; Peethambar, Sanenahalli K. [Kuvempu University, Jnana Sahyadri, Karnataka (India). Dept. of Plant Pathology

    2011-07-01

    A series of some new 3-isoxazoline substituted methyl-3-methoxy-2-(4-oxo-3,4- dihydrophthalazine-1-yl)prop-2-enoate derivatives were designed and synthesized from methyl- (4-oxo-3,4-dihydrophthalazine-1-yl)acetate, which in turn was prepared from phthalic anhydride. The structures of synthesized new compounds were characterized by spectral data and studied for their antimicrobial activities and cytotoxicity. Several of these compounds showed good antimicrobial activity (author)

  5. Hydroxamic acid derivatives as potent peptide deformylase inhibitors and antibacterial agents.

    Science.gov (United States)

    Apfel, C; Banner, D W; Bur, D; Dietz, M; Hirata, T; Hubschwerlen, C; Locher, H; Page, M G; Pirson, W; Rossé, G; Specklin, J L

    2000-06-15

    Low-molecular-weight beta-sulfonyl- and beta-sulfinylhydroxamic acid derivatives have been synthesized and found to be potent inhibitors of Escherichia coli peptide deformylase (PDF). Most of the compounds synthesized and tested displayed antibacterial activities that cover several pathogens found in respiratory tract infections, including Chlamydia pneumoniae, Mycoplasma pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. The potential of these compounds as antibacterial agents is discussed with respect to selectivity, intracellular concentrations in bacteria, and potential for resistance development.

  6. Synthesis, characterization and antimicrobial activities of amide derivatives of febuxostat intermediate

    Directory of Open Access Journals (Sweden)

    Sreedhar Badvel

    2015-06-01

    Full Text Available A series of new carboxamide derivatives of 3-(4-(5-(ethoxycarbonyl-4-methylthiazol-2-ylphenoxypropionic acid were synthesized by Schotten-Baumann reaction. The newly synthesized compounds were characterized by IR, NMR and mass spectral analysis. The target molecules were evaluated for their efficacy as antimicrobial agents in vitro by disc diffusion method. Compounds 4c, 4f, 4g and 4i showed high inhibitory activity.

  7. Pharmacological characterization of tachykinin tetrabranched derivatives.

    Science.gov (United States)

    Ruzza, Chiara; Rizzi, Anna; Malfacini, Davide; Cerlesi, Maria Camilla; Ferrari, Federica; Marzola, Erika; Ambrosio, Caterina; Gro, Cristina; Severo, Salvadori; Costa, Tommaso; Calo, Girolamo; Guerrini, Remo

    2014-09-01

    Peptide welding technology (PWT) is a novel chemical strategy that allows the synthesis of multibranched peptides with high yield, purity and reproducibility. Using this technique, we have synthesized and pharmacologically characterized the tetrabranched derivatives of the tachykinins, substance P (SP), neurokinin A (NKA) and B (NKB). The following in vitro assays were used: calcium mobilization in cells expressing human recombinant NK receptors, BRET studies of G-protein - NK1 receptor interaction, guinea pig ileum and rat urinary bladder bioassays. Nociceptive behavioural response experiments were performed in mice following intrathecal injection of PWT2-SP. In calcium mobilization studies, PWT tachykinin derivatives behaved as full agonists at NK receptors with a selectivity profile similar to that of the natural peptides. NK receptor antagonists display similar potency values when tested against PWT2 derivatives and natural peptides. In BRET and bioassay experiments PWT2-SP mimicked the effects of SP with similar potency, maximal effects and sensitivity to aprepitant. After intrathecal administration in mice, PWT2-SP mimicked the nociceptive effects of SP, but with higher potency and a longer-lasting action. Aprepitant counteracted the effects of PWT2-SP in vivo. The present study has shown that the PWT technology can be successfully applied to the peptide sequence of tachykinins to generate tetrabranched derivatives characterized with a pharmacological profile similar to the native peptides. In vivo, PWT2-SP displayed higher potency and a marked prolongation of action, compared with SP. © 2014 The British Pharmacological Society.

  8. Resveratrol derivatives: a patent review (2009 - 2012).

    Science.gov (United States)

    Pezzuto, John M; Kondratyuk, Tamara P; Ogas, Talysa

    2013-12-01

    There is currently a wealth of information on the effects of resveratrol and its derivatives in therapeutic, cosmetic and nutraceutical patent applications. Structure-activity studies of the resveratrol scaffold provide a foundation for the development of new analogs with potent activity or other beneficial properties. Ongoing research has yielded promising results and potential use in the treatment of various diseases. This review provides analysis of patents published from January 2009 to April 2013. There is a focus on different approaches for the production of resveratrol derivatives, combinations of new derivatives with old drugs, and applications in therapeutic areas, nutraceutical compositions and cosmetics. The ability of resveratrol to interact with a disparate array of subcellular targets is uncanny. Nonetheless, even though limited or no toxicity is apparent, the molecule is not a panacea due to lack of potency and issues with bioavailability. Thus, as witnessed by a number of patents, a large assortment of derivatives have been synthesized under the guise of having superior characteristics for treating or preventing various diseases or for use as neutraceutics and cosmetics. Some of these suppositions are probably correct, but evidence-based applications are essentially nil due to a lack of commitment in terms of investing the resources necessary for the conduct of obligatory clinical trials. Current usage is largely based on anecdotes and publicity. Hopefully, at some point in time, it will be possible to follow a standard protocol with a predicable outcome.

  9. Synthesis and Characterization of Novel Thiourea Derivatives and Their Nickel and Copper Complexes

    OpenAIRE

    Gün Binzet; Gülten Kavak; Nevzat Külcü; Süheyla Özbey; Ulrich Flörke; Hakan Arslan

    2013-01-01

    New benzoyl thiourea derivatives and their nickel and copper complexes were synthesized. The structure of the synthesized compounds were confirmed by elemental analysis, FT-IR, and 1H NMR techniques. Four of the synthesized compounds are analyzed by X-ray single crystal diffraction technique. Whereas N,N-dimethyl-N′-(4-fluorobenzoyl)thiourea, N,N-diethyl-N′-(4-fluorobenzoyl)thiourea, and N,N-di-n-butyl-N′-(4-fluorobenzoyl) thiourea crystallize in the monoclinic system, bis(N,N-di-n-propyl-N′-...

  10. Regioselective synthesis and preliminary cytotoxic activity properties of tetrazole appendage N-substituted piperazine derivatives

    OpenAIRE

    Kommula Dileep; Mohana Rao Katiki; Busam Ramalingeswara Rao; V. P. S. Vishnu Vardhan; Ramakrishna Sistla,; Jagadeesh Babu Nanubolu; Madugula Sree Rama Murty

    2017-01-01

    A series of 1-(4-substituted)-4-(3-((1-(substituted)-1H-tetrazol-5-yl)thio)propyl)piperazine derivatives were ( 6a-t) synthesized by KF-Al2O3 mediated S-alkylation of 5-thio-substituted tetrazole with 1-(3-chloropropyl)-4-(4-substituted)piperazine. The structures of the newly synthesized compounds were characterized by NMR and MS spectral data. Further, the regioselective formation of C-S bond was unambiguously confirmed by single crystal X- ray diffraction. All the synthesized compounds were...

  11. Synthesizing exoplanet demographics from radial velocity and microlensing surveys. I. Methodology

    International Nuclear Information System (INIS)

    Clanton, Christian; Gaudi, B. Scott

    2014-01-01

    Motivated by the order of magnitude difference in the frequency of giant planets orbiting M dwarfs inferred by microlensing and radial velocity (RV) surveys, we present a method for comparing the statistical constraints on exoplanet demographics inferred from these methods. We first derive the mapping from the observable parameters of a microlensing-detected planet to those of an analogous planet orbiting an RV-monitored star. Using this mapping, we predict the distribution of RV observables for the planet population inferred from microlensing surveys, taking care to adopt reasonable priors for, and properly marginalize over, the unknown physical parameters of microlensing-detected systems. Finally, we use simple estimates of the detection limits for a fiducial RV survey to predict the number and properties of analogs of the microlensing planet population such an RV survey should detect. We find that RV and microlensing surveys have some overlap, specifically for super-Jupiter mass planets (m p ≳ 1 M Jup ) with periods between ∼3-10 yr. However, the steeply falling planetary mass function inferred from microlensing implies that, in this region of overlap, RV surveys should infer a much smaller frequency than the overall giant planet frequency (m p ≳ 0.1 M Jup ) inferred by microlensing. Our analysis demonstrates that it is possible to statistically compare and synthesize data sets from multiple exoplanet detection techniques in order to infer exoplanet demographics over wider regions of parameter space than are accessible to individual methods. In a companion paper, we apply our methodology to several representative microlensing and RV surveys to derive the frequency of planets around M dwarfs with orbits of ≲ 30 yr.

  12. 4-Aminoquinoline derivatives

    DEFF Research Database (Denmark)

    Singh, Shailja; Agarwal, Drishti; Sharma, Kumkum

    2016-01-01

    Synthetic quinoline derivatives continue to be considered as candidates for new drug discovery if they act against CQ-resistant strains of malaria even after the widespread emergence of resistance to CQ. In this study, we explored the activities of two series of new 4-aminoquinoline derivatives a...

  13. The Dangers of Derivatives.

    Science.gov (United States)

    Blumenstyk, Goldie

    1994-01-01

    Heavy investment in derivatives, whose value derives from the price movement of some underlying security, has meant heavy losses for some colleges and universities despite the fact that institutional investors are required to assure that they understand the risks of such investment. (MSE)

  14. Vitamin D derivatives

    International Nuclear Information System (INIS)

    Deluca, H.F.; Schnoes, H.K.; Napoli, J.L.; Fivizzani, M.A.

    1982-01-01

    The chemical preparation of 26,27-isotopically labelled vitamin D 3 derivatives of high specific activity is described. These labelled vitamin D derivatives are useful in the determination of vitamin D metabolite levels in the blood and tissues of man and animals. (U.K.)

  15. Fluorescence properties of 6-aryl-2‧-deoxy-furanouridine and –pyrrolocytidine and their derivatives

    Science.gov (United States)

    Ro, Jong Jin; Go, Gui Han; Wilhelmsson, L. Marcus; Hyean Kim, Byeang

    2018-01-01

    2‧-deoxyfuranouridine derivatives presenting various aryl groups have been synthesized through Cu(I)-catalyzed intramolecular cyclizations. Moreover, corresponding pyrrolo-dC derivatives have been synthesized and both families of compounds thoroughly characterized using UV/vis and fluorescence spectroscopy as well as time-dependent density functional theory calculations. The photophysical characterization, show that our newly synthesized derivatives of the important pyrrolo-dC family have high fluorescence quantum yields (QYs) and brightness values. Pyrrolo-dC derivative, 3a, shows an environment sensitive QY of up to >60% and brightness of almost 3000, in low polarity solvents and excitation and emission maxima between 365–381 nm and 479–510 nm, respectively, in solvents of different polarities. Two other derivatives, 3b and 3c, show high QYs and brightness values of up to 3300 that are fairly insensitive to their microenvironment. These promising photophysical features suggest future applicability as fluorescent nucleobase analogs.

  16. Coordination chemistry and applications of versatile 4,5-diazafluorene derivatives.

    Science.gov (United States)

    Annibale, Vincent T; Song, Datong

    2016-01-07

    This perspective review will examine the coordination chemistry and applications of metal complexes of 4,5-diazafluorene derivatives. The versatile derivatives of 4,5-diazafluorene can serve multiple roles, and display a number of coordination modes. The ambidentate derivatives with multiple coordination sites can allow for the syntheses of coordination polymers, multimetallic, and macrocyclic complexes. In addition, certain 4,5-diazafluorene derivatives can serve as spectator ligands to support reactivity at the metal centre, or as reactive actor ligands engaging in atypical reactivity patterns. The applications of metal complexes of 4,5-diazafluorene derivatives in catalysis, photochemistry and photophysics, as well as in bioinorganic chemistry are also surveyed.

  17. Coumarin amide derivatives as fluorescence chemosensors for cyanide anions

    International Nuclear Information System (INIS)

    Wu, Qianqian; Liu, Zhiqiang; Cao, Duxia; Guan, Ruifang; Wang, Kangnan; Shan, Yanyan; Xu, Yongxiao; Ma, Lin

    2015-01-01

    Four coumarin amide derivatives with 4-methyl coumarin or pyrene as terminal group have been synthesized. Their photophysical properties and recognition properties for cyanide anions have been examined. The results indicate that the compounds can recognize cyanide anions with obvious absorption and fluorescence spectra change, at the same time, obvious color and fluorescence change can be observed by naked eye. The in situ hydrogen nuclear magnetic resonance spectra and photophysical properties change confirm that Michael additions between the chemosensors and cyanide anions take place at the 4-position of coumarin. - Highlights: • Four coumarin amide derivatives with 4-methyl coumarin or pyrene as terminal group were synthesized. • The compounds can recognize cyanide anions with obvious absorption and fluorescence spectra change. • Michael additions between the chemosensors and cyanide anions take place at the 4-position of coumarin

  18. Potential radiosensitizing agents. 5. 2-Substituted benzimidazole derivatives

    International Nuclear Information System (INIS)

    Gupta, R.P.; Larroquette, C.A.; Agrawal, K.C.

    1982-01-01

    A series of 2-substituted benzimidazoles and their derivatives have been synthesized and tested for their ability to selectively sensitize hypoxic Chinese hamster cells (V-79) toward the lethal effect of ionizing radiation. These compounds were prepared by reacting the 2-substituted benzimidazoles with 1,2-epoxy-3-methoxypropane in the presence of potassium carbonate. Reaction of the 2-nitro and 2-methylfonyl analogue with the epoxide also yielded a cyclized material, which was confirmed to be a benzimidazo[2,1-b]oxazole. In an attempt to increase the electron affinity, 5- or 6-nitro-2-substituted-benzimidazoles were also synthesized and then reacted with the epoxide to yield the corresponding 1-substituted derivatives. The results of the biological tests for the radiosensitizing activity of these agents against Chinese hamster cells (V-79) in culture indicated that the 2-nitro-substituted analogues were the most effective sensitizers in this series

  19. Synthesizing modeling of power generation and power limits in energy systems

    International Nuclear Information System (INIS)

    Sieniutycz, Stanislaw

    2015-01-01

    Applying the common mathematical procedure of thermodynamic optimization the paper offers a synthesizing or generalizing modeling of power production in various energy generators, such as thermal, solar and electrochemical engines (fuel cells). Static and dynamical power systems are investigated. Dynamical models take into account the gradual downgrading of a resource, caused by power delivery. Analytical modeling includes conversion efficiencies expressed in terms of driving fluxes. Products of efficiencies and driving fluxes determine the power yield and power maxima. While optimization of static systems requires using of differential calculus and Lagrange multipliers, dynamic optimization involves variational calculus and dynamic programming. In reacting mixtures balances of mass and energy serve to derive power yield in terms of an active part of chemical affinity. Power maximization approach is also applied to fuel cells treated as flow engines driven by heat flux and fluxes of chemical reagents. The results of power maxima provide limiting indicators for thermal, solar and SOFC generators. They are more exact than classical reversible limits of energy transformation. - Highlights: • Systematic evaluation of power limits by optimization. • Common thermodynamic methodology for engine systems. • Original, in-depth study of power maxima. • Inclusion of fuel cells to a class of thermodynamic power systems

  20. Cytotoxic Effect of a Novel Synthesized Carbazole Compound on A549 Lung Cancer Cell Line.

    Directory of Open Access Journals (Sweden)

    Refilwe P Molatlhegi

    Full Text Available Increased death rates due to lung cancer have necessitated the search for potential novel anticancer compounds such as carbazole derivatives. Carbazoles are aromatic heterocyclic compounds with anticancer, antibacterial and anti-inflammatory activity. The study investigated the ability of the novel carbazole compound (Z-4-[9-ethyl-9aH-carbazol-3-yl amino] pent-3-en-2-one (ECAP to induce cytotoxicity of lung cancer cells and its mechanism of action. ECAP was synthesized as a yellow powder with melting point of 240-247 °C. The 3-(4,5-dimethythiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT, lipid peroxidation and comet assays were used to assess the cytotoxic effect of the compound on A549 lung cancer cells. Protein expression was determined using western blots, apoptosis was measured by luminometry (caspase-3/7, -8 and -9 assay and flow cytometry was used to measure phosphatidylserine (PS externalisation. ECAP induced a p53 mediated apoptosis of lung cancer cells due to a significant reduction in the expression of antioxidant defence proteins (Nrf2 and SOD, Hsp70 (p < 0.02 and Bcl-2 (p < 0.0006, thereby up-regulating reactive oxygen species (ROS production. This resulted in DNA damage (p < 0.0001, up-regulation of Bax expression and caspase activity and induction of apoptosis in lung cancer cells. The results show the anticancer potential of ECAP on lung cancer.