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First Synthesis (first + synthesis)
Selected AbstractsFirst Syntheses and Electronic Properties of (Oligo)phenothiazine,C60 Dyads.CHEMINFORM, Issue 2 2007Nadine Bucci Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] First Synthesis of Argadin: A Nanomolar Inhibitor of Family-18 ChitinasesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 24 2006Mark J. Dixon No abstract is available for this article. [source] First Synthesis of Heparan Sulfate Tetrasaccharides Containing both N -Acetylated and N -Unsubstituted Glucosamine,Search for Putative 10E4 EpitopesCHEMBIOCHEM, Issue 12 2006Daniel Hamza Dr. A methodology allowing the differentiation of azido groups in protected oligosaccharides was optimized. It allowed the first synthesis of tetrasaccharides 1 and 2 containing both N-acetylated and N-unsubstituted glucosamine, as well as glucuronic and/or iduronic acid residues. These tetrasaccharides were then examined for their ability to interact with 10E4, an antibody recognizing early lesions in the brain of scrapie prion-infected mice. [source] ChemInform Abstract: N-(,,,-Difluorovinyl)oxazolidin-2-ones: First Synthesis and Application in [3 + 2]- and [4 + 2]-Cycloaddition-Type Reactions.CHEMINFORM, Issue 6 2010Thanh Binh Nguyen Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: First Synthesis of Non-Symmetrical "Phthalimidoyl Active Ester" Bi-Dentate Cross-Linking Reagents Having an Acid Chloride, 2-Benzothiazole, or 1-Benzotriazol Group.CHEMINFORM, Issue 18 2009Md. Chanmiya Sheikh Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: First Synthesis of 3,6,- and 3,7,-Biquinoline Derivatives.CHEMINFORM, Issue 44 2008Sidonie Broch Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: First Synthesis and Further Functionalization of 7-Chloro-imidazo[2,1-b][1,3]thiazin-5-ones.CHEMINFORM, Issue 28 2008Clemens Lamberth Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] First Synthesis of Nitro-Substituted 2,2-Diphenyl-2H-1-benzopyrans via the ipso-Nitration Reaction.CHEMINFORM, Issue 48 2007Lahoussine Bougdid Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] First Synthesis of Picealactone C. A New Route Toward Taxodione-Related Terpenoids from Abietic Acid.CHEMINFORM, Issue 21 2007Enrique Alvarez-Manzaneda Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] First Synthesis of Group-14 Polyanions by Extraction of a Binary Alloy with dmf and a Novel Conformation of the (Ge9,Ge9)6- Dimer: Crystal Structures of [K6(Ge9,Ge9)](dmf)12, [Rb6(Ge9,Ge9)](dmf)12 and [K2.5Cs3.5(Ge9,Ge9)] (dmf)12.CHEMINFORM, Issue 47 2006Anke Nienhaus Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] First Synthesis of a Steroid Containing an Unstable 19-Nor-androsta-1,5-dien-3-one System.CHEMINFORM, Issue 34 2006Christine Cadot Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] First Synthesis of ,-Keto Sulfoxides by a Palladium-Catalyzed Carbonylative Suzuki Reaction.CHEMINFORM, Issue 7 2006Mercedes Medio-Simon Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access the actual ChemInform Abstract, please click on HTML or PDF. [source] First Synthesis and X-Ray Crystal Structure of Hexahydrobenzo[b]pyrido[3,4,5-de]-1,6-naphthyridines.CHEMINFORM, Issue 4 2006Leonid G. Voskressensky Abstract For Abstract see ChemInform Abstract in Full Text. [source] First Synthesis of Pyrrolo[1,2:1,,2,]azepino[5,6-b]indole Derivatives.CHEMINFORM, Issue 48 2003Julien Perron Abstract For Abstract see ChemInform Abstract in Full Text. [source] First Synthesis of Phosphatidylcholine and Cholesteryl Derivatives Bearing an Unsaturated Aldehyde ResidueCHEMINFORM, Issue 2 2003Arnold N. Onyango Abstract For Abstract see ChemInform Abstract in Full Text. [source] First Synthesis of Optically Pure Propargylic N-Hydroxylamines by Direct, Highly Diastereoselective Addition of Terminal Alkynes to Nitrones.CHEMINFORM, Issue 51 2002Roger Faessler Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: First Synthesis of Propano-dibenzo[1,3]dioxocin Type Compounds from Condensation of p-Substituted Phenol Derivatives with Glutaraldehyde in Trifluoroacetic Acid.CHEMINFORM, Issue 37 2002Ali Rahmatpour Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: 3,9-Dihydro-2H-[1,2,4]-oxadiazolo[3,2-b]quinazolin-2-ones: First Synthesis of the Parent Heterocycle, 7- and 9-Substituted Derivatives.CHEMINFORM, Issue 13 2001Patrice P. Renaut Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] First synthesis and x-ray crystal structure of hexahydrobenzo[b]pyrido[3,4,5- de]-1,6-naphthyridinesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2005Leonid G. Voskressensky The reaction of 10-carboxamido tetrahydrobenzo[b][1,6]naphthyridines 1-3 with activated terminal alkynes in DMF/methanol resulted with the formation of hexahydrobenzo[b]pyrido[3,4,5- de]-1,6-naph-thyridines 7-10 - representatives of a new heterocyclic system. [source] First synthesis of the bismole-containing conjugated polymerJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 16 2006Yasuhiro Morisaki Abstract We successfully synthesized the first conjugated polymer containing a bismuth atom in the conjugated main chain by incorporating a bismuth atom into the cyclopentadiene framework (bismole), which was constructed by a polymer reaction. A synthetic procedure and characterization of the obtained polymers were discussed. This bismole-containing conjugated polymer exhibited moderate bluish green photoluminescence in solution. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4857,4863, 2006 [source] A versatile synthesis of [2,3,4- 13C3]isoflavonesJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 3 2010Nawaf Al-Maharik Abstract A flexible synthetic method is presented, which allows all the key isoflavones (daidzein, genistein, glycitein, formononetin and biochanin A) to be prepared in 13C-labelled form via the same route, involving the thallium(III)-mediated oxidative rearrangement of a key chalcone intermediate. This method results in the incorporation of 13C atoms at the 2, 3 and 4 positions of the isoflavone skeleton. We also report the first syntheses of 13C-labelled versions of the daidzein metabolites, equol and ODMA. Copyright © 2009 John Wiley & Sons, Ltd. [source] Synthesis of A,[1-42] and its derivatives with improved efficiencyJOURNAL OF PEPTIDE SCIENCE, Issue 2 2007Márta Zarándi Abstract It has been proved that the principal component of senile plaques is aggregates of ,-amyloid peptide (A,) in cases of one of the most common forms of age-related neurodegenerative disorders, Alzheimer's disease (AD). Although the synthetic methods for the synthesis of A, peptides have been developed since their first syntheses, A,[1-42] is still problematic to prepare. The highly hydrophobic composition of A,[1-42] results in aggregation between resin-bound peptide chains or intrachain aggregation which leads to a decrease in the rates of deprotection and repetitive incomplete coupling reactions during 9-flurenylmethoxycarbonyl (Fmoc) synthesis. In order to avoid aggregation and/or disrupt internal aggregation during stepwise Fmoc solid phase synthesis and to improve the quality of crude products, several attempts have been made. Since highly pure A, peptides in large quantities are used in biological experiments, we wanted to develop a method for a rational synthesis of human A,[1-42] with high purity and adequate yield. This paper reports a convenient methodology with a novel solvent system for the synthesis of A,[1-42], its N -terminally truncated derivatives A,[4-42] and A,[5-42], and A,[1-42] labeled with 7-amino-4-methyl-3-coumarinylacetic acid (AMCA) at the N -terminus using Fmoc strategy. The use of 10% anisole in Dimethylformamide/Dichloromethane (DMF/DCM) can substantially improve the purity and yield of crude A,[1-42] and has been shown to be an optimal coupling condition for the synthesis of A,[1-42]. Anisole is a cheap and simple aid in the synthesis of ,difficult sequences' where other solvents are less successful in the prevention of aggregation during the synthesis. Copyright © 2006 European Peptide Society and John Wiley & Sons, Ltd. [source] Mixed Aromatic Acyloin Condensations with Recombinant Benzaldehyde Lyase: Synthesis of ,-Hydroxydihydrochalcones and Related ,-Hydroxy KetonesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6-7 2003Monica Sanchez-Gonzalez Abstract Recombinant benzaldehyde lyase (BAL), expressed and purified from E.,coli strain JM-109, was used to catalyze the condensation of a series of methoxybenzaldehydes and phenylacetaldehyde in the synthesis of ,-(R)-hydroxydihydrochalcones. Enantiomerically pure 1-hydroxy-1,3-diphenylpropan-2-ones and o -anisoin were also obtained as products of the BAL reaction. The R absolute configurations of chiral centers were determined by CD spectroscopy. ,-(R)-Hydroxydihydrochalcones and 1-hydroxy-1,3-diphenylpropan-2-ones are valuable synthons for chemoenzymatic syntheses of flavonoids. This is the first synthesis of ,-(R)-hydroxydihydrochalcones by a microbial enzyme. [source] Life history and ecology of seahorses: implications for conservation and managementJOURNAL OF FISH BIOLOGY, Issue 1 2004S. J. Foster We present the first synthesis of the life history and ecology of seahorses, compare relationships for seahorses with other marine teleosts and identify research needs. Seahorses occurred primarily amidst temperate seagrasses and tropical coral reefs. Population densities were generally low, ranging from 0 to 0·51 individuals m,2, but reached 10 m,2 in some patches. Inferred life spans ranged from 1 to 5 years. Seahorses consumed live prey and possibly changed diet as they grew. Growth rates are poorly investigated to date. Reproduction and mating systems are the best-studied aspects of seahorse ecology. The relationship between size at first maturity and maximum size in seahorses conformed to that for other marine teleosts. All seahorse species were monogamous within a cycle, but some were polygamous across cycles. Direct transfer of clutches to the brood pouch of the male fish made it difficult to measure clutch size in live seahorses. After brooding, males released from c. 5 to 2000 young, depending on species and adult size. Newborn young measured from 2 to 20 mm in length, which was a narrower size range than the 17-fold difference that occurred in adult size. Newborn body size had no relationship to adult size. Both eggs and young were larger than expected among marine teleosts, even when considering only those with parental care, but brood size at release was lower than expected, perhaps because the young were more developed. The size of adults, eggs and young increased with increasing latitude, although brood size did not. Considerable research is needed to advance seahorse conservation and management, including (a) fisheries-dependent and fisheries-independent abundance estimates, (b) age- or stage-based natural and fishing mortalities, (c) growth rates and age at first maturity, and (d) intrinsic rates of increase and age- or size-specific reproductive output. Current data confirm that seahorses are likely to be vulnerable to high levels of exploitation. [source] Facile regiospecific syntheses of N -,,N -1(,)-dialkyl-l-histidinesJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 6 2007Surendra Kumar Nayak Two diverse methodologies describe the first synthesis of suitably protected N -,,N -1(,)-dialkyl-Lhistidine derivatives. Synthesis of suitably protected N -,,N -1(,)-dialkyl-L-histidines 7-9 containing different alkyl groups at the N -, and N -1(,) positions was achieved in four steps starting from L-histidine methyl ester. Whereas, in the one-step alternate route N -,-Boc-L-histidine methyl ester upon direct and simultaneous N -, and N -1(,) alkylation with various alkyl halides in the presence of sodium hydride in DMF easily afforded N -,,N -1(,)-dialkyl-L-histidines 14 containing identical alkyl group at the N -, and N -1(,) positions in high yields. Both procedures allowed facile entry to methyl and other higher alkyl groups at the N -,-position of the histidine ring [source] Synthesis of the lipid peroxidation product 4-hydroxy-2(E)-nonenal with 13C stable isotope incorporationJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 2 2008I. Jouanin Abstract The aim of this work was to synthesize 13C internal standards for the quantification of 4-hydroxy-2(E)-nonenal (HNE), a lipid peroxidation product, and of the etheno-adducts possibly formed by HNE damage to DNA nucleobases. We designed an eight-step synthesis starting from ethyl 2-bromoacetate and giving access to 4-[(tetrahydro- 2H -pyran-2-yl)oxy]-2(E)-nonenal. This compound is a precursor of HNE. The scheme was then used to produce the 13C precursor [1,2- 13C2]-4-[(tetrahydro- 2H -pyran-2-yl)oxy]-2(E)-nonenal. [1,2- 13C2]-HNE was obtained by acid deprotection. All the intermediary and final compounds were fully characterized by IR, HRMS, 1H and 13C NMR. It is the first synthesis of HNE which enables the incorporation of two 13C labels at determined positions. Copyright © 2008 John Wiley & Sons, Ltd. [source] Synthesis of 15N-labelled nornicotine and 15N-labelled nicotineJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 13 2001Giang Vo-Thanh Abstract The synthesis of 15N-labelled nornicotine 2 and 15N-labelled nicotine 1 is described via the reductive aminocyclization of a 1,4-ketoaldehyde with a corresponding amine in the presence of sodium cyanoborohydride. Yields of 30% and 26%, respectively, were obtained from 3-bromopyridine. The 15N-label has been easily introduced from ammonium- 15N-labelled chloride as an inexpensive label source. As far as we are aware, this is the first synthesis of 15N-labelled nicotine. Copyright © 2001 John Wiley & Sons, Ltd. [source] Frontal free-radical copolymerization of urethane,acrylatesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 9 2006Ting Hu Abstract We report the first synthesis of urethane,acrylate copolymers via free-radical frontal polymerization. In a typical run, the appropriate amounts of the reactants (urethane,acrylate macromonomer and 2-hydroxyethyl acrylate) and initiator (ammonium persulfate) were dissolved in dimethyl sulfoxide. Frontal polymerization was initiated by the heating of the wall of the tube with a soldering iron, and the resultant hot fronts were allowed to self-propagate throughout the reaction vessel. Once it was initiated, no further energy was required for the polymerization to occur. The dependence of the front velocity and front temperature on the initiator concentration was investigated. The front temperatures were between 55 and 65 °C, depending on the persulfate concentration. Thermogravimetric analysis indicated that the urethane,acrylate copolymers had higher thermal stability than pure frontally prepared polyurethane. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3018,3024, 2006 [source] Empirical tests for ecological exchangeabilityANIMAL CONSERVATION, Issue 3 2005Russell B. Rader The concept of ecological exchangeability, together with genetic exchangeability, is central to both the Cohesion Species Concept as well as to some definitions of Evolutionarily Significant Units. While there are well-established criteria for measuring genetic exchangeability, the concept of ecological exchangeability has generated considerable confusion. We describe a procedure that uses the complementary strengths, while recognising the limitations, of both molecular genetic data and ecological experiments to determine the ecological exchangeability of local populations within a species. This is the first synthesis of a combined approach (experiments and genetics) and the first explicit discussion of testing ecological exchangeability. Although it would be ideal to find functional genes that interact to influence quantitative traits resulting in ecological differences (e.g. growth, size, fecundity), we suggest that our current knowledge of functional markers is too limited for most species to use them to differentiate adaptively different local populations. Thus, we argue that ecological experiments using whole organisms combined with neutral markers that indicate evolutionary divergence, provide the strongest case for detecting adaptive differences among local populations. Both genetic divergence and ecological experiments provide the best information for infering ecological exchangeability. This procedure can be used to decide which local populations should be preserved to maintain intraspecific variation and to determine which populations would enhance captive-breeding programs, augment endangered local populations and could best be used to re-introduce native species into historically occupied areas. [source] First Synthesis of Heparan Sulfate Tetrasaccharides Containing both N -Acetylated and N -Unsubstituted Glucosamine,Search for Putative 10E4 EpitopesCHEMBIOCHEM, Issue 12 2006Daniel Hamza Dr. A methodology allowing the differentiation of azido groups in protected oligosaccharides was optimized. It allowed the first synthesis of tetrasaccharides 1 and 2 containing both N-acetylated and N-unsubstituted glucosamine, as well as glucuronic and/or iduronic acid residues. These tetrasaccharides were then examined for their ability to interact with 10E4, an antibody recognizing early lesions in the brain of scrapie prion-infected mice. [source] | |||||||||||||