反应详情

A solution of 0.050 g of 7β-phenylacetylaminocepham-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 under reflux for 2 hours. 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 for 2 hours
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