PREPARATION OF CILAZAPRIL INTERMEDIATES

摘要

This application relates to an improved process for the preparation of 6, 11-dioxo-1,2,3,4,6,11-hexahydro-pyridazino(1,2-b)naphthalazine-1-carboxylic acid, and its esters and salts as well as its resolution with an optically pure amine to get (s)-6,11-dioxo-1,2,3,4,6,11-hexahydro-pyridazino(1,2-b)naphthalazine-1-carboxylic acid. It also relates use of these intermediates in the preparation of cilazapril.