PROCESS FOR PREPARING (-)PYRIDOBENZOXAZINE CARBOXYLIC ACID DERIVATIVES

摘要

The present invention provides a process for preparing optically active (-)pyridobenzoxazine carboxylic acid derivative and pharmaceutically acceptable salt thereof by employing a starting material of (+)ethyl 2-(4-chloro-5-fluoro-2-halo-3-nitobenzoyl)-3-[(1-hydroxypropy-2(S)-yl)amino]acrylate. According to the present invention, optically active (-)pyridobenzoxazine carboxylic acid derivative can be manufactured from low-priced 4-chloro-5-fluorobenzoic acid derivative in a simple and economical manner.