C([O:5][C:6](=[O:63])[C@H:7]([CH2:59][CH:60]([CH3:62])[CH3:61])[NH:8][CH:9]1[CH2:15][CH2:14][CH2:13][CH2:12][CH:11]([C@@H:16]2[O:48][C@H:47]([CH2:49][O:50]C(=O)C3C=CC=CC=3)[C@H:37]([O:38]C(=O)C3C=CC=CC=3)[C@H:27]([O:28]C(=O)C3C=CC=CC=3)[C@H:17]2[O:18]C(=O)C2C=CC=CC=2)[CH2:10]1)(C)(C)C.Cl.Cl.C(OC(=O)[C@H](CC(C)C)N)(C)(C)C.C([BH3-])#N.[Na+]>ClCCl.CO>[C@@H:16]1([CH:11]2[CH2:12][CH2:13][CH2:14][CH2:15][CH:9]([NH:8][C@H:7]([C:6]([OH:63])=[O:5])[CH2:59][CH:60]([CH3:61])[CH3:62])[CH2:10]2)[O:48][C@H:47]([CH2:49][OH:50])[C@H:37]([OH:38])[C@H:27]([OH:28])[C@H:17]1[OH:18]Step B--Synthesis of Nα-(3-(2,3,4,6-Tetra-O-benzoyl-β-D-galactopyranosyl)cyclohept-1-yl)-L-leucine tert-Butyl Ester: To the product from Step A (50 mg, 71 μmol) and L-leucine tert-butyl ester dihydrochloride (80 mg, 354 μmol) in dichloromethane (700 μL) and methanol 700 μL) was added sodium cyanoborohydride (2 mg). After 48 h, the mixture was concentrated and purified by column chromatography (SiO2, toluene/ethyl acetate, 8:1) to give the title compound (48 mg, 78%).
Wird geladen…