Efficient process for the preparation of S-(R,S)-N-1,3-benzodioxol-5-yl)butyl-3,3-diethyl-24-4-methyl-1-piperazinyl)carbonylphenoxy-4-oxo-1-azetidine carboxamide, a human leukocyte elastase inhibitor

摘要

Processes for the preparation of S-(R,S)-N-1,3-benzodioxol-5-yl)butyl-3,3-diethyl-24-4-methyl-1-piperazinyl)carbonylphenoxy-4-oxo-l-azetidine carboxamide, a useful inhibitor of human leukocyte elastase (HLE), are described. The process including (a) contacting a compound of formula (II): ;with a compound of formula (III): ;in a first polar solvent system in the presence of an aqueous base and a phase transfer catalyst, to form the title compound, or a salt form thereof.