[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][CH:18]2O)=[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.C(N(CC)CC)C.CS(Cl)(=O)=O.CS([O-])(=O)=O>CN(C)C=O.C(OCC)(=O)C>[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:29]=[CH:30][CH:31]=[CH:32][CH:33]=4)[C@H:21]3[S:20][CH2:19][CH:18]=2)=[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]=1To a solution of 3-hydroxy-7beta-phenylacetylaminocepham-4-carboxylic acid diphenylmethyl ester (2) in dimethylformamide (9.5 parts, dried over Molecular Sieves) cooling at -50° C. under nitrogen are added triethylamine (4 equivalents) and then methanesulfonyl chloride (2 equivalents) over 3 minutes at -52° to -45° C. After 2.5 hours at -55° to -45° C., the produced methanesulfonate (3) solution is stirred for 50 minutes at -15° to -12° C. diluted with ethyl acetate, washed with water, 5% hydrochloric acid, and water, dried over sodium sulfate, and concentrated. The residue is crystallized from methanol to give 7beta-phenylacetylamino-3-cephem-4-carboxylic acid diphenylmethyl ester (6). (Yield: 81.53%). mp. 166° C. (decomposition).
Wird geladen…