PROCESS FOR PREPARATION OF ATAZANAVIR OR ITS BISULFATE SALT

摘要

The present invention relates to an improved process for the preparation of atazanavir bisulfate, an inhibitor of retroviral aspartate protease. The process of the present invention comprises conversion of 1,1-dimethylethyl[(2S,3R)-4-chloro-3-hydroxy-phenylbutan-2-yl]carbamate (Formula II) into 1-[4-(pyridine-2-yl)-phenyl]-4(S)-5 hydroxy-2-N-tert-butoxycarbonylamino-5(S)—N—(N-methoxycarbonyl-(L)-tert-leucyl)amino-6-phenyl-2-azahexane (Formula VII) without isolating intermediate compounds formed therein, followed by its subsequent conversion to atazanavir or its bisulfate salt.