Hydrochloric Acid → Diphenylmethyl 3-acetoxymethyl-7-[2-(2-tritylamino-4-thiazolyl)-2-hydroxyimino-acetamido]-ceph-3-eme-4-carboxylate

Participants

Reaction Steps

A mixture of 2.775 g of the product of Step A, 14 ml of acetone and 4.5 ml of N hydrochloric acid was stirred for 2 hours at room temperature and the acetone was evaporated under reduced pressure. 20 ml of ethyl acetate were added thereto and the mixture was stirred and decanted. The organic phase was washed 4 times with 10 ml of slightly salted water and the wash waters were extracted with 5 ml of ethyl acetate. The combined organic phases were dried and vacuum filtered and the filter was rinsed with ethyl acetate. The filtrate was evaporated to dryness under reduced pressure and the residue was taken up in ether and was crystallized. Efflorescence occurred and the mixture was vacuum filtered. The product was rinsed with ether and was dried to obtain 1.88 g of the syn isomer of diphenylmethyl 3-acetoxymethyl-7-[2-(2-tritylamino-4-thiazolyl)-2-hydroxyimino-acetamido]-ceph-3-eme-4-carboxylate with a Rf=0.5 (eluant-ether containing 20% acetone).

Provenance & Evidence