Hydrochloric Acid → 3-(5-bromo-1H-indol-3-yl)-2-(4-but-2-ynyloxy-benzenesulfonyl amino)-propionic acid

Participants

Reaction Steps

2-(4-But-2-ynyloxy-benzenesulfonylamino)-3-(5-bromo-1H-indol-3-yl)-propionic acid ethyl ester (0.100 g, 0.193 mmol) was dissolved in 0.5 mL tetrahydrofuran. To the solution was added MeOH (0.5 mL) and 1 N NaOH (0.4 mL, 0.4 mmol). The reaction mixture was placed in a shaker for 10 hours at room temperature. The solution was acidified with 1N HCl and extracted with ethyl acetate (3×3 mL). The organic solution was concentrated and the residue was purified by RP-HPLC to give 0.089 g (94%) of the title compound as a pale yellow solid. 1H NMR (DMSO-d6): 400 MHz δ 12.65 (bs, 1H), 11.01 (s, 1H), 8.08 (d, J=8.8 Hz, 1H), 7.48 (m, 3H), 7.26 (d, J=8.8 Hz, 1H), 7.13 (m, 2H), 6.89 (d, J=9.2 Hz, 2H), 4.77 (q, J=2.8 Hz, 2H), 3.82 (q, J=8.4 Hz, 1H), 3.01 (dd J=14.6, 6.4 Hz, 1H), 2.82 (dd J=14.6, 8.0 Hz, 1H), 1.83 (t, J=2.4 Hz, 3H); HRMS: calcd for C21H20BrN2O5S (ESI+, Br79, [M+H]1+), 491.0271; found 491.0287; LCMS m/z (ESI) [M−H] 489 (Br79), retention time=2.75 min.

Provenance & Evidence