反应详情

N-[(1,1-Demethylethoxy)carbonyl]-L-norleucine (432 mg., 1.87 mmole) is dissolved in tetrahydrofuran (10 ml.) at room temperature under argon. The mixture is cooled to 0° and treated with triethylamine (0.66 ml., 4.56 mmole) and pivaloyl chloride (0.28 ml.). After one hour at 0°, the reaction mixture is treated with a solution of 1-[(S)-2-[[[(1-amino)pentyl]methoxyphosphinyl]oxy]-1-oxopropyl]-L-proline, ethyl ester (isomer B) (706 mg., 1.87 mmole) in tetrahydrofuran (10 ml.) according to the procedure of Example 4 part (e) to give 759 mg. of 1-[(S)-2-[[[1-[[(S)-2-[[(1,1-dimethylethoxy)carbonyl]amino]-1-oxohexyl]amino]pentyl]methoxyphosphinyl]oxy]-1-oxopropyl]-L-proline, ethyl ester (isomer B). TLC (silica gel; methylene chloride:methanol:acetic acid, 20:1:1) Rf =0.74.

1. temperatureThe mixture is cooled to 0°
2. customto give 759 mg