反应详情

tert-Butyl (E)-(2S,3S)-3-[(S)-2-(4-butoxy-phenyl)-1-methoxycarbonyl-ethylcarbamoyl]-12,12-difluoro-2-hydroxy-2-(2-methoxy-ethyl)-nonadec-4-enoate (No. 5552820; 13.9 mg, 0.0188 mmol) was dissolved in dichloromethane (2.1 mL), and trifluoroacetic acid (TFA, 0.7 mL) was added to the solution. The mixture was stirred at room temperature for 16 hours, and the solvent was distilled off. To the residue was added dichloromethane, and the solvent was again distilled off. This operation was repeated twice. Subsequently, HPLC purification (water with 0.05% TFA-acetonitrile with 0.05% TFA) was performed to obtain (E)-(2S,3S)-3-[(S)-2-(4-butoxy-phenyl)-1-methoxycarbonyl-ethylcarbamoyl]-12,12-difluoro-2-hydroxy-2-(2-methoxy-ethyl)-nonadec-4-enoic acid (No. 5514403; 5.6 mg, 44% yield, white powder).

1. distillationthe solvent was distilled off
2. additionTo the residue was added dichloromethane
3. distillationthe solvent was again distilled off
4. customSubsequently, HPLC purification (water with 0.05% TFA-acetonitrile with 0.05% TFA)