1-Methyl-3-p-tolyltriazene → 3-Methoxy-7beta-phenylacetylamino-3-cephem-4-carboxylic acid diphenylmethyl ester
Reaction equation
[C:1]1([CH:7]([O:14][C:15]([CH:17]2[N:22]3[C:23](=[O:35])[C@@H:24]([NH:25][C:26](=[O:34])[CH2:27][C:28]4[CH:33]=[CH:32][CH:31]=[CH:30][CH:29]=4)[C@H:21]3[S:20][CH2:19][C:18]2=[O:36])=[O:16])[C:8]2[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[CH3:37]N=NNC1C=CC(C)=CC=1>C1C=CC=CC=1>[C:1]1([CH:7]([O:14][C:15]([C:17]2[N:22]3[C:23](=[O:35])[C@@H:24]([NH:25][C:26](=[O:34])[CH2:27][C:28]4[CH:33]=[CH:32][CH:31]=[CH:30][CH:29]=4)[C@H:21]3[S:20][CH2:19][C:18]=2[O:36][CH3:37])=[O:16])[C:8]2[CH:9]=[CH:10][CH:11]=[CH:12][CH:13]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1Participants
4
Procedure
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.