摘要:
The process according to the invention for the preparation of enantiomerically pure cyclopentane-.beta.-amino acids of the general formula (I) ##STR1## in which A and D have the meanings given in the description, is characterized in that meso-dicarboxylic acid anhydrides are first converted by asymmetric alcoholysis with allyl alcohols and in the presence of a chiral amine base present in enantiomerically pure form, in inert solvents, via the intermediate enantiomerically pure salt stage, into the enantiomerically pure dicarboxylic acid monoesters, in a further step these dicarboxylic acid monoesters are intermediately converted, in the sense of a Curtius rearrangement by reaction with azides, into the corresponding acid azides, and are subsequently converted into the corresponding rearranged isocyanates and the isocyanates are then reacted with allyl alcohols to give the compounds of the general formula (VII), and finally the cyclopentane-.beta.-amino acids of the general formula (I) are obtained by splitting off the urethane and ester function.
摘要:
This invention relates to benzolididene compounds of the formula ##STR1## in which R.sup.2 represents the radical ##STR2## in which R.sup.4 and R.sup.5 are identical or different and denote halogen, cyano, ethinyl, trifluoromethoxy, methylthio, nitro, trifluoromethyl or straight-chain or branched alkyl, alkenyl, alkinyl or alkoxy having up to 4 carbon atoms, and one of the substituents optionally represents hydrogen, or a salt thereof.