反应详情

To a solution of 222 mg (S)-2-tert-butoxycarbonylamino-4-(2H-tetrazol-5-yl)-butyric acid in 5 ml DMF were added 300 mg HATU, 541 μl DIPEA and 245 mg piperazine-1-carboxylic acid butyl ester hydrotrifluoroacetate. After 1 h the solution was concentrated, taken up with dichloromethane and washed with aqueous LiCl (4%) and 0.1 M HCl. The crude product thus obtained was used in the next reaction step without further purification.

1. concentrationAfter 1 h the solution was concentrated
2. washwashed with aqueous LiCl (4%) and 0.1 M HCl