Hydrochloric Acid → (2R)-3-[4'-(2-benzylbenzofuran-3-yl)biphen-4-ylmethylsulfanyl]-2-tert-butoxy-carbonylamino-propionic acid

Participants

Reaction Steps

1N Sodium hydroxide (2 mL) was added to a stirred solution of (2R)-methyl-3-[4′-(2-benzylbenzofuran-3-yl)biphen-4-ylmethylsulfanyl]-2-tert-butoxycarbonylamino-propionate (100 mg) in a mixture of tetrahydrofuran (6 mL) and methanol (2 mL). The solution was stirred for 1 hour and then acidified to pH 3 with 1N hydrochloric acid. The reaction mixture was extracted with ethyl acetate (3×10 mL). The combined extract was washed with water, brine, dried over anhydrous MgSO4, filtered and concentrated in vacuo. Purification of the product by flash column chromatography, using 5% methanol in methylene chloride as eluent, afforded the title compound as a white solid (82 mg, 84%): mp. 89-90° C. Rf=0.50 (10% methanol in dichloromethane). 1H NMR (DMSO-d6, 300 MHz) δ 7.8 (2H, d, J=9 Hz, Ar—H), 7.6 (6H, m, Ar—H), 7.4 (2H, d, J=9 Hz, Ar—H), 7.28 (5H, m, Ar—H), 7.21 (2H, d, J=8 Hz, Ar—H), 6.42 (1H, d, J=8 Hz, NH), 4.26 (2H, s, PhCH2), 3.95 (1H, m, CHN), 3.75 (2H, s, PhCH2S), 2.9 (1H, dd, J=15, 5 Hz, CHHCHN), 2.74 (1H, dd, J=15, 8 Hz, CHHCHN), 1.39 (9H, s, tBu); ESI-LCMS e/z calcd for C36H35NO5S 593.74, found 617 (M+Na)+.

Provenance & Evidence