C(OC([N:8]1[CH2:12][CH:11]([O:13][C:14](=[O:19])[C:15]([CH3:18])([CH3:17])[CH3:16])[CH2:10][N:9]1[C:20]([O:22][CH2:23][C:24]1[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=1)=[O:21])=O)(C)(C)C.S(Cl)(Cl)=O.Cl>CO>[CH2:23]([O:22][C:20]([N:9]1[CH2:10][CH:11]([O:13][C:14](=[O:19])[C:15]([CH3:17])([CH3:16])[CH3:18])[CH2:12][NH:8]1)=[O:21])[C:24]1[CH:29]=[CH:28][CH:27]=[CH:26][CH:25]=14-(2,2-Dimethylpropionyloxy)pyrazolidine-1,2-dicarboxylic acid 1-benzyl ester 2-tert-butyl ester, 29, (1.76 g, 4.33 mmol) is dissolved in methanol (40 mL) and the solution cooled to 0° C. Thionyl chloride (3.16 mL, 43.3 mmol) is added dropwise and the reaction allowed to warm to room temperature and continue stirring 12 hours. The reaction solution is concentrated in vacuo to give afford 1.45 g (98% yield) of the desired product as the HCl salt as an off-white solid.
불러오는 중…