Trifluoroacetic acid → N-[2-({4-[4-(3-Bromo-4-fluorophenyl)-5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl]-1,2,5-oxadiazol-3-yl}amino)ethyl]sulfamide

Participants

Reaction Conditions

Reaction Steps

To a 25-mL flask was added tert-butyl {[[2-({4-[4-(3-bromo-4-fluorophenyl)-5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl]-1,2,5-oxadiazol-3-yl}amino)ethyl](4-methoxybenzyl)amino]sulfonyl}(4-methoxybenzyl)carbamate (40.2 mg, 0.050 mmol) in trifluoroacetic acid (TFA, 0.50 mL, 6.5 mmol) at ambient temperature. This reaction mixture was heated to 70° C. under N2 and stirred for 1 h. HPLC indicated reaction completed. The reaction mixture was cooled to room temperature and the TFA was evaporated. The residual TFA was removed by treatment with dichloromethane (3×10 mL) followed by evaporation in vacuum. The residue was then triturated with dichloromethane and methanol to give the desired product (20 mg, 87%) as a crude off-white solid. 1H NMR (400 MHz, DMSO-d6) δ 8.08 (dd, J=6.2, 2.5 Hz, 1 H), 7.72 (m, 1 H), 7.59 (t, J=8.7 Hz, 1 H), 6.67 (t, J=5.9 Hz, 1H), 6.55 (s, 2H) 6.52 (t, J=6.0 Hz, 1 H), 3.38 (dd, J=12.7, 6.3 Hz, 2 H), 3.11 (dd, J=12.3, 6.3 Hz, 2H); C12H11BrFN7O5S (MW 464.23), LCMS (EI) m/e 487.8/489.8 (M++Na).

Provenance & Evidence