| abstract |
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. |