17682-05-2Relevant academic research and scientific papers
The method of preparation of enantiomerically enriched products of condensation from racemic acids or acids of the low enentiomeric purity
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Page/Page column 7, (2012/03/08)
The method of obtaining enantiomerically enriched condensation products consists of subjecting a racemic acid or an acid of low enantiomeric purity to the action of a condensing reagent - a chiral N-triazinylammonium tetrafluoroborate (formula 1), a chira
Design, synthesis, and application of enantioselective coupling reagent with a traceless chiral auxiliary
Kolesinska, Beata,Kaminski, Zbigniew J.
supporting information; experimental part, p. 765 - 768 (2009/09/06)
(Chemical Equation Presented) Stable chiral N-triazinylbrucinium tetrafluoroborate enantioselectively activates racemic carboxylic acids yielding enantiomerically enriched amides, esters, and dipeptides with er from 8:92 to 0.5:99.5. Due to the departure
A novel generation of coupling reagents. Enantiodifferentiating coupling reagents prepared in situ from 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) and chiral tertiary amines
Kaminski,Kolesinska,Kaminska,Gora
, p. 6276 - 6281 (2007/10/03)
Coupling of racemic N-protected amino acids with amino components by means of 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) in the presence of chiral tertiary amines such as strychnine, brucine, and sparteine proceeds enantioselectively, affording appropriate amides or dipeptides in 69-85% yield. The configuration of the preferred enantiomer and enantiomeric enrichment depend on the structures of the amine and carboxylic acid. Calculated Kagan enantioselectivity parameters (s) are in the range 1.6-195. Chiral triazinylammonium chlorides formed in situ from CDMT and chiral tertiary amines are postulated as reactive intermediates involved in the process of enantioselective activation of N-protected amino acids.
A New Route toward 4-Substituted Pyrazino[2,1-b]quinazoline-3,6-dione Systems. Total Synthesis of Glyantrypine
Cledera, Pilar,Avendano, Carmen,Carlos Menendez
, p. 1743 - 1749 (2007/10/03)
Treatment of sodium N-(o-azidobenzoyl)aminoacylglycinates 8 with acetic anhydride afforded 1-acetyl-4-(o-azidobenzoyl)-2,5-piperazinediones 7, with complete retention of the stereochemistry. The intramolecular aza Wittig reactions of compounds 7 in the pr
Design and Synthesis of Enkephalin Analogues: Part II - Synthesis of 2, Met5>-Enkephalin Alkylamides Having Morphinomimetic Activity
Dhotre, B. J.,Mathur, K. B.
, p. 1231 - 1236 (2007/10/02)
Alkylamides of 2, Met5>-enkephalin have been synthesized by two different routes.The first method consists of the sequential peptidation of Phe-Met-ONBzl by 2,4,5-trichlorophenyl esters of Boc-Gly, Boc-D-Ala and Boc-Tyr to get
KINETICS OF AMINOLYSIS FOR 1-THIO-β-D-GLUCOPYRANOSYL ESTERS OF N-ACYLALANINES
Horvat, S.,Tomic, S.,Jericevic, Z.
, p. 1047 - 1050 (2007/10/02)
The kinetics of aminolysis of 1-thio-β-D-glucopyranosyl esters of N-protected alanines (1) in dichloromethane at 26 deg C, by ethyl glycinate, under pseudo-first-order conditions follows the relationship kobsd=k2.Significant differences were obserwed in the rates of dipeptide forming aminolysis for 1-thiolesters 1a-1f, depending on N-acyl substituents and the configuration of alanine.
