Pyridine → HCID 178475883, compound

Participants

Reaction Steps

A solution of 0.5 g of dicyclohexylcarbodiimide in 5 ml of methylene chloride was added to a mixture of 1.024 g of the product of Step C, 0.656 mg of tert.-butyl 7-amino-3-acetoxymethyl-ceph-3-eme-4-carboxylate and 2 ml of pyridine and the mixture was stirred for one hour at room temperature. The mixture was vacuum filtered and 25 ml of N hydrochloric acid were added to the filtrate. The mixture was stirred for 5 minutes and the decanted organic phase was washed with 25 ml of water, was dried and evaporated to dryness under reduced pressure. The residue was taken up in isopropyl ether and efflorescenced. The mixture was vacuum filtered and the recovered product was rinsed with isopropyl ether and dried to obtain 1.778 g of raw product. The latter was dissolved in 4 ml of ethyl acetate and the solution was treated with activated carbon and was filtered. 20 ml of isopropyl ether were added to the filtrate over 5 minutes with stirring and after stirring for another 5 minutes, the mixture was vacuum filtered. The recovered product was rinsed with isopropyl ether and dried to obtain 1.412 g of the syn isomer of tert.-butyl 3-acetoxymethyl-7-[2-(2-tritylamino-4-thiazolyl)-2-(tetrazol-5-yl-methyloxyimino)-acetamido]-ceph-3-eme-4-carboxylate in the form of a white product melting at 158° C.

Provenance & Evidence