Tributyltin azide → Valsartan benzyl ester

Participants

Reaction Steps

L-valine benzyl ester hydrochoride is N-alkylated with 4-bromomethyl-2′-cyanobiphenyl, the product 4-[(2′-cyanobiphenyl-4-yl)methyl]-(L)-valine benzyl ester so formed is N-acylated with valeryl chloride to give N-[(2′-cyanobiphenyl-4-yl)methyl]-N-valeryl-(L)-valine benzyl ester. N-[(2′-cyanobiphenyl-4-yl)methyl]-N-valeryl-(L)-valine benzyl ester is treated with tributyltin azide to give valsartan benzyl ester. Valsartan benzyl ester is subjected to catalytic hydrogenation using for example palladium-charcoal as catalyst to give valsartan.

Provenance & Evidence