Patent ID: 6716983
Filing Date: 2004-04-06
Classification: A61P,C07B,C07D

Abstract:
A process for preparing an S type 2-substituted hydroxy-2-indolidinylbutyric ester compound of the formula [II]: wherein R0 is a residue of a nitrogen-containing fused heterocyclic carboxylic acid having an absolute configuration of â€œRâ€  which is obtained by removing hydroxy group from the carboxyl group of said carboxylic acid (in which the nitrogen atom contained in the residue is protected), R1 and R2 are a lower alkyl group, and E is an ester residue, which comprises reacting a 2-halo-2-indolidinylacetic ester compound of the formula [III]: wherein X is a halogen atom, and R1, R2 and E are as defined above, with an R type nitrogen-containing fused heterocyclic carboxylic acid compound of the formula [IV]: RoOHâ€ƒâ€ƒ[IV]wherein Ro is as defined above, or a salt thereof to give a 2-substituted hydroxy-2-indolidinylacetic ester compound of the formula [I]: wherein the symbols are as defined above, and then ethylating 2-position of the resultant compound [I].