O-benzyl-L-valine toluene-p-sulphonate → 4-Pyridyl-ethanesulfonyl-valine benzyl ester

Participants

Reaction Steps

To 1 gm of valine benzyl ester p-toluene-sulfonic acid salt in 40 ml of CH2Cl2 at 0° C. was added 1.12 gm of 4-pyridylsulfonyl chloride (U.S. Pat. No. 431,504 (1982)) and 1.9 ml of triethylamino. After 1 hour, the solution was washed with water and extracted with CH2Cl2 (2×100 ml), dried and concentrated. Silica gel column chromotography provided 4-pyridyl-ethanesulfonyl-valine benzyl ester which was treated with 10% Pd/C in methanol under hydrogen atmosphere to provide the desired product in 85% overall yeild.

Provenance & Evidence