Phosphorus oxychloride → 7-[2-(2-(2-thienyl)acetoxyimino)-2-(3-hydroxyphenyl)acetamido]-3-(1methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

Dimethylformamide (0.4 g.), phosphorus oxychloride (0.81 g.), methylene chloride (20 ml.), ethyl acetate (10 ml.) and 2-[2-(2-thienyl)acetoxyimino]-2-(3-hydroxyphenyl)acetic acid (syn isomer) (1.68 g.) were treated in a manner as in example 1(B) to give an ethyl acetate solution. On the other hand, 7-amino-3-(1-methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid (1.64 g.) and bis(trimethylsilyl)acetamide (3.55 g.) were dissolved in ethyl acetate (20 ml.) and stirred at -20° C., to which was added the above obtained solution. Then the reaction mixture was stirred for 1 hour at the same temperature. Water was added thereto and the mixture was stirred for 10 minutes. The ethyl acetate layer was separated. The aqueous layer was extracted with ethyl acetate. Two ethyl acetate layers were combined. The extract was washed with a saturated aqueous solution of sodium chloride and dried. The solvent was distilled off. The residue was pulverized with a mixed solution of diisopropylether and ether, collected by filtration and washed to give 7-[2-(2-(2-thienyl)acetoxyimino)-2-(3-hydroxyphenyl)acetamido]-3-(1methyl-1H-tetrazol-5-yl)thiomethyl-3-cephem-4-carboxylic acid (syn isomer) (2.2 g.).

Provenance & Evidence