反应详情

2.28 g of 7-amino-3-formyl-3-cephem-4-carboxylic acid are bisilylated as described in example 19 with 5.4 ml of N,O-bis-(trimethylsilyl)-acetamide, reacted with phenylacetic acid chloride, and then hydrolysed with 0.4 ml of water. The hydrolysed reaction mixture is treated with 1 g of activated charcoal and then filtered. The yellow filtrate is mixed with 20 ml of a 10% solution of diphenyldiazomethane in dichloromethane, and then concentrated to 10 ml in vacuo. The product is precipitated from the residue of evaporation thus obtained by adding 100 ml of n-hexane. 7-phenylacetamido-3-formyl-3-cephem-4-carboxylic acid benzhydrylester is thus obtained as a slightly yellowish product.

1. filtrationfiltered
2. additionThe yellow filtrate is mixed with 20 ml of a 10% solution of diphenyldiazomethane in dichloromethane
3. concentrationconcentrated to 10 ml in vacuo
4. customThe product is precipitated from the residue of evaporation
5. customthus obtained