[CH2:1]([O:8][C:9]([N:11]1[CH2:18][CH2:17][CH2:16][C@H:12]1[C:13]([OH:15])=O)=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C(N(CC)CC)C.ClC(OCC)=O.[NH2:32][C:33]1[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=1>C1COCC1.C(OCC)(=O)C>[CH2:1]([O:8][C:9]([N:11]1[CH2:18][CH2:17][CH2:16][C@H:12]1[C:13]([NH:32][C:33]1[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=1)=[O:15])=[O:10])[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1In 50 ml of THF was dissolved 4.99 g of N-benzyloxycarbonyl-L-proline (20) and after adding thereto 2.23 g of triethylamine and 2.39 g of ethyl chloroformate, the reaction was maintained for 20 minutes under ice-cooling. To the reaction mixture was added 2.79 g of aniline and the reaction was performed for one hour under ice-cooling. The solvent was distilled off, the residue thus formed was dissolved in ethyl acetate, and the solution was washed, in succession, with an aqueous solution of 1N hydrochloric acid, a saturated aqueous sodium hydrogen, carbonate solution, and then a saturated aqueous sodium chloride solution. The organic layer thus formed was dried by anhydrous sodium sulfate and then concentrated to dryness. The residue was recrystallized from chloroform-ethyl acetate-hexane to provide 5.20 g of (S)-1-benzyloxycarbonyl-N-phenyl-2-pyrrolidinecarboxamide (93) having a melting point of 143°-144° C.
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