[CH3:1][O:2][C:3]([C@@H:5]1[CH2:9][C@@H:8]([OH:10])[CH2:7][NH:6]1)=[O:4].[CH3:11][O:12][C:13]([NH:15][C@@H:16]([CH:20]([CH3:22])[CH3:21])[C:17](O)=[O:18])=[O:14].CN(C(ON1N=NC2C=CC=NC1=2)=[N+](C)C)C.F[P-](F)(F)(F)(F)F.C(N(CC)CC)C>C(Cl)Cl>[CH3:1][O:2][C:3]([C@@H:5]1[CH2:9][C@@H:8]([OH:10])[CH2:7][N:6]1[C:17](=[O:18])[C@@H:16]([NH:15][C:13]([O:12][CH3:11])=[O:14])[CH:20]([CH3:22])[CH3:21])=[O:4]To a solution of (2S,4R)-4-hydroxy-pyrrolidine-2-carboxylic acid methyl ester in dry DCM (200 mL) was added (S)-2-methoxycarbonylamino-3-methyl-butyric acid (10 g, 55 mmol), HATU (24 g, 63.25 mmol), and triethylamine (16.7 g, 165 mmol. The reaction mixture was stirred at RT overnight. DCM (200 mL) was added and the solution was washed with brine, dried, concentrated and purified by silica gel column chromatography (eluted with petroleum ether:EtOAc 10:1 to 1:4)) to give the title intermediate as a yellow oil (20 g). (m/z): [M+H]+ calcd for C13H22N2O6 303.15. found 303.1.
Wird geladen…