N-SUBSTITUTED-1,2,3,4-TETRAHYDRO-3-YLQUINOLINECARBOXYLIC ACID OR N-SUBSTITUTED 2-INDOLINECARBOXYLIC ACID HAVING AN ABSOLUTE R CONFIGURATION

摘要

N-SUBSTITUTED-1,2,3,4-TETRAHYDRO-3-YLQUINOLINECARBOXYLIC ACID OR N-SUBSTITUTED 2-INDOLINECARBOXYLIC ACID HAVING AN ABSOLUTE R CONFIGURATIONABSTRACT OF THE DISCLOSURE:A process for preparing S type 2-substituted hydroxy-2-indolidinyl-butyric ester compound [II]:[err] [II]wherein R[err] is residue of nitrogen-containing fused heterocyclic carboxylic acid having absolute configuration of "R"(in which the nitrogen atom is protected).R[err] and R[err] are lower alkyl group, and E is ester residue, which is useful as an intermediate for preparing camptothecin derivatives having antitumor activities, which comprises 2-ethylating 2-substituted hydroxy-2-indolidinylacetic estercompound [I]:[err] [I]wherein the symbols are as defined above.