反应详情

A solution of 0.050 g of 7β-phenylacetylamino-cepham-3-one-4ξ-carboxylic acid diphenylmethyl ester and 0.020 g of 1-methyl-3-(4-methylphenyl)-triazene in 5 ml of benzene is boiled for 2 hours under reflux. After cooling, the mixture is evaporated under reduced pressure and the residue is purified by thin layer chromatography (silica gel; 1×20 cm; system: toluene/ethyl acetate, 3:1). The zone (Rf~0.18) which is visible under ultraviolet light (λ=254μ) is eluted with acetone and 3-methoxy-7β-phenylacetylamino-3-cephem-4-carboxylic acid diphenylmethyl ester is obtained, ultraviolet absorption spectrum (in ethanol): λmax =264μ (ε=6,300); infrared absorption spectrum (in methylene chloride): Characteristic bands at 2.94μ, 5.63μ, 5.83μ, 5.94μ, 6.26μ and 6.68μ.

1. temperatureunder reflux
2. temperatureAfter cooling
3. customthe mixture is evaporated under reduced pressure
4. customthe residue is purified by thin layer chromatography (silica gel; 1×20 cm; system: toluene/ethyl acetate, 3:1)
5. washis eluted with acetone