Acetone → cis 4-Fluoromethyl-3-[2-(2-tritylamino-4-thiazolyl)-2-difluoromethoxyimino-acetamido]-2-oxo-azetidine

Participants

Reaction Steps

0.339 g of tosyl chloride were added to a mixture of 0.914 g of the syn isomer of 2-(2-tritylamino-4-thiazolyl)-2-difluoromethoxyimino-acetic acid, 7 ml of acetone and 0.25 ml of trietylamine and the mixture was stirred for 50 minutes after which a solution of 0.23 g of cis 4-fluoromethyl-3-amino-2-oxo-azetidine hydrochloride, 7 ml of methylene chloride and 0.45 ml of triethylamine was added thereto. The mixture was stirred for 90 minutes and was evaporated to dryness. The residue was added to methylene chloride and water and then 3 ml of 10% sodium bicarbonate solution. The mixture was stirred and the decanted aqueous phase was extracted with methylene chloride. The combined organic phases were dried and evaporated to dryness. The residue was taken up in ethanol and the solution was cooled and vacuum filtered. The crystals were rinsed with ethanol, then with ether and dried to obtain 0.537 g of racemate of the syn isomer of cis 4-fluoromethyl-3-[2-(2-tritylamino-4-thiazolyl)-2-difluoromethoxyimino-acetamido]-2-oxo-azetidine. STEP B: Racemate of the syn isomer of cis 4-fluoromethyl-3-[2-(2-amino-4-thiazolyl)-2-difluoromethoxyimino-acetamido]-2-oxo-azetidine-1-sulfonic acid

Provenance & Evidence