Ethanol → Sodium 3-acetoxymethyl-7-[2-(2-amino-4-thiazolyl)-2-methoxyimino-acetamido]-ceph-3-eme-4-carboxylate

Participants

Reaction Conditions

Reaction Steps

A solution of 6 g of sodium acetate in 20 ml of water was added with stirring at 20° C. to 50 ml of 98% ethanol and with continued stirring 25 g of an ethanol solvate of the syn isomer of 3-acetoxymethyl-7-[2-(2-amino-4-thiazolyl)-2-methoxyimino-acetamido]-ceph-3-eme-4-carboxylic acid were added thereto. After dissolution occured, the solution was cooled to 0° C. and 50 ml of 98% ethanol were added thereto dropwise with stirring. Activated carbon was added to the solution which was then filtered and the filtrate was heated to 20° C. Crystallization spontaneously occured shortly thereafter and filtration by aspiration was effected at room temperature 16 hours later. The recovered product was washed with a 1-7 water-ethanol mixture, with ethanol and then with ether to obtain colorless crystals of the D form of the syn isomer of sodium 3-acetoxymethyl-7-[2-(2-amino-4-thiazolyl)-2-methoxyimino-acetamido]-ceph-3-eme-4 -carboxylate which after drying under reduced pressure contained 4.8% of water (by Fischer). The spectrum of X-ray diffraction and the infrared spectrum in nujol confirmed the D form.

Provenance & Evidence