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Component Condensation (component + condensation)
Selected AbstractsUnexpected Synthesis of Rearranged 3,4-Dihydroquinazolines by a Sequential Ugi 4CC/Aza-Wittig/Carbodiimide-Mediated CyclizationEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 6 2010Ping He Abstract The 2,3,4-trisubstituted 3,4-dihydroquinazolines 4 were unexpectedly obtained from a sequential Ugi four component condensation (4CC)/aza-Wittig/carbodiimide-mediated cyclization. [source] An efficient one-pot procedure for the preparation of 1,3,4-thiadiazoles in ionic liquid [bmim]BF4 as dual solvent and catalystHETEROATOM CHEMISTRY, Issue 3 2008Shahnaz Rostamizadeh The one-pot three component condensation of hydrazine hydrate with substituted phenylisothiocyanates followed by the addition of substituted benzaldehydes in the presence of ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4) and in the absence of any other catalyst under mild condition afforded 1,3,4-thiadiazoles in excellent yields. The reaction workup is simple, and the ionic liquid was easily recovered from the reaction and reused. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:320,324, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20432 [source] A new strategy for the synthesis of cyclopeptides containing diaminoglutaric acidJOURNAL OF PEPTIDE SCIENCE, Issue 5 2001Tom Bayer Abstract A new synthesis of orthogonally protected diaminoglutaric acid containing peptides using the Ugi four component condensation is presented. To demonstrate that this method is useful to replace cystine by diaminoglutaric acid in biologically interesting peptides, we built up two cyclic somatostatin analogues deriving from Sandostatin and from TT-232. A photolytically cleavable amine derivative of the nitroveratryl type is used for the Ugi four component condensation. Because of a racemic build up of the new stereocentre of the diaminoglutaric acid, and racemization of the isonitrile component, four diastereomeric peptides resulted that were separated by HPLC. The stereochemistry of the cyclopeptides could be easily and unambiguously assigned by chiral gas chromatography and a reference sample of enantiomerically pure (2S,4S)-diaminoglutaric acid. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd. [source] SnCl2 · 2H2O-catalyzed one-pot synthesis of 4(3H)-quinazolinones from anthranilic acid, ortho esters, and amines under solvent free conditionsJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 2 2010Min Wang A simple, efficient, and green procedure for the one-pot synthesis of 4(3H)-quinazolinones by three components condensation of anthranilic acid, ortho esters, and amines in the presence of SnCl2 · 2H2O has been developed. The reaction occurred within short reaction time at room temperature under solvent-free conditions to afford the title products in excellent yields. J. Heterocyclic Chem., (2010). [source] | ||||||||||