反应详情

To a mixture of 2-(2-pyridyloxy)acetic acid hydrochloride (1.5 g) and acetyl chloride (8 ml) was added at -30° C. phosphorus pentachloride (3.3 g), and the mixture was stirred at room temperature for 18 hours. Precipitated crystals were collected by filtration and washed with a small amount of acetyl chloride and diethyl ether and dried to give 2-(2-pyridyloxy)acetyl chloride (1.3 g). A mixture of 7-(D-2-phenylglycinamido)-3-methyl-3-cephem-4-carboxylic acid (2.5 g) and trimethylsilylacetamide (0.0288 mole) in methylene chloride (70 ml) was stirred for 1.5 hours. The solution was cooled to 3° C. and the above obtained 2-(2-Pyridyloxy)acetyl chloride was added thereto. The resultant mixture was stirred under ice-cooling for 2 hours and concentrated. To the residue was added ice-water and the resultant powder was filtrated and washed with acetone containing water and acetone in turn to give powder (1.4 g). The filtrate and washings were collected together and extracted with ethyl acetate four times. The ethyl acetate extracts were washed with water, dried and concentrated to give powder (0.4 g). Thus obtained powders (1.4 g) and (0.4 g) were combined together and recrystallized from methanol to give crystals (0.9 g) of 7-{D-2-[2-(2-pyridyloxy)acetamido]-2-phenylacetamido}-3-methyl-3-cephem-4-carboxylic acid, mp 209° to 211° C. (dec).

1. customPrecipitated crystals
2. filtrationwere collected by filtration
3. washwashed with a small amount of acetyl chloride and diethyl ether
4. customdried