反应详情

A solution of 2.74 g (3.49 mmol) of benzyl[1-{2-(4-chlorophenyl)-1-[(2,2-diethoxyethyl)-isopropylcarbamoyl]ethylcarbamoyl}-2-(2,4-dichlorobenzenesulfonylamino)ethyl]-carbamate in 45 ml of formic acid was heated at 60° C. for 6 h. The reaction mixture was then concentrated in vacuo, and the residue was purified by chromatography on 40 g of SiO2 (eluent DCM followed by 20% EtOAc/DCM). 2.25 g of the cyclized compound are obtained as a colorless solid.

1. concentrationThe reaction mixture was then concentrated in vacuo
2. customthe residue was purified by chromatography on 40 g of SiO2 (eluent DCM followed by 20% EtOAc/DCM)