Water → (2R)-Methyl-3-[4'-(2-benzylbenzofuran-3-yl)biphen-4-ylmethylsulfanyl]-2-tert-butoxycarbonylaminopropionate

Participants

Reaction Steps

N-Boc-L-Cysteine methyl ester (260 mg, 0.23 mL, 1.1 mmol) was added dropwise to a stirred suspension of 2-Benzyl-3-(4′-bromomethylbiphen-4-yl)benzofuran (500 mg, 1.1 mmol) and cesium carbonate (720 mg, 2.21 mmol) in anhydrous dimethylformamide (20 mL). The reaction was stirred at room temperature for 2 hrs (TLC control) and then poured into water (100 mL) and extracted with diethyl ether (3×100 mL). The combined extract was washed with water, brine (3×), dried over anhydrous MgSO4, filtered and concentrated in vacuo. Purification using 30% ethyl acetate in heptane as eluent afforded the title compound as a white solid (620 mg, 92%): 1H NMR (CDCl3, 300 MHz): δ 7.70 (2H, m, Ar—H), 7.64 (2H, m, Ar—H), 7.60 (3H, m, Ar—H), 7.48 (1H, m, Ar—H), 7.42 (2H, m, Ar—H), 7.26-7.36 (7H, m, Ar—H), 5.32 (1H, d, J=8 Hz, NH), 4.58 (1H, m, CHN), 4.26 (2H, PhCH2), 3.79 (2H, s, PhCH2S), 3.76 (3H, s, OMe), 2.95 (1H, dd, J=13, 5 Hz, CHHCHN), 2.84 (1H, dd, J=13, 7 Hz, CHHCHN), 1.46 (9H, s, CMe3); ESI-LCMS e/z calcd for C37H37NO5S 607.760, found 608 (M+H)+, 630 (M+Na)+.

Provenance & Evidence