488703-61-3Relevant academic research and scientific papers
Enantiomerically pure β-amino acids: A convenient access to both enantiomers of trans-2-aminocyclohexanecarboxylic acid
Berkessel, Albrecht,Glaubitz, Katja,Lex, Johann
, p. 2948 - 2952 (2007/10/03)
Enantiomerically pure trans-2-aminocyclohexanecarboxylic acid is an important building block for helical β-peptides. We report here that this amino acid can be obtained from trans-cyclohexane-1,2-dicarboxylic acid in good yield by a simple one-pot procedure comprising cyclization to the anhydride, amide formation with ammonia, and a subsequent Hofmann-type degradation with phenyliodine(III) bis(trifluoroacetate) (PIFA) as the oxidant. The N-Fmoc- and N-BOC-protected derivatives were obtained by treatment of the amino acid with Fmoc-OSu and BOC2O, respectively. The N-BOC derivative could be prepared in even better overall yield by a one-pot procedure leading directly from trans-cyclohexane-1,2-dicarboxylic acid to the N-BOC-protected amino acid. Both enantiomers of the starting trans-1,2-cyclohexanedicarboxylic acid can be obtained easily and in large quantities by separating commercially available racemic trans-1,2-cyclohexanedicarboxylic acid using either (R)- or (S)-1-phenethylamine. X-ray crystallography of the diastereomerically pure salt obtained from (R)-1-phenethylamine revealed that the configuration of the diacid component is (1R,2R), and not (1S,2S) as reported in the literature. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.
Thiazolidinone compounds and composition for angina pectoris comprising the compounds as an active ingredient
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, (2008/06/13)
A thiazolidinone compound represented by general formula (I) or a pharmacoligically acceptable salt thereof, STR1 wherein W represents sulfur or oxygen and X represents --N(R1)--, or alternatively X represents sulfur or oxygen and W represents --N(R1)--, and R1 represents hydrogen, alkyl or substituted alkyl; R2 and R3 are the same or different from each other, and each represents hydrogen, alkyl, substituted alkyl, aryl, or 5- or 6-membered heteroaryl; R4 represents hydrogen, alkyl or substituted C1 -C4 alkyl; R5 represents substituted cycloalkyl which may contain nitrogen, provided the substituents include --B--ONO2 (wherein B represents a single bond or alkylene) as the indispensable member and alkyl groups as optional members; and A represents a single bond or alkylene, has an excellent anti-anginal effect and thus is useful as an angina pectoris remedy or preventive.
