反应详情

The procedure used for the preparation of 5a was repeated with 4c (335 mg, 1.27 mmol) and 2N LiOH (2.22 mL) to provide 5c (296 mg, 99%) as a white solid, which was recrystallized from EtOAc/hexane. mp 175.0°-176.0° C.; IR (KBr) 3450, 3300-2500 (br), 1729, 1697, 1449, 1189 cm-1 ; 1H NMR (DMSO-d6) δ3.83 (2H, s, CH2), 7.37 (1H, dd, J=8.5 and 4.4 Hz, Ar), 7.44 (1H, d, J=8.5 Hz, Ar), 7.63 (1H, s), 8.14 (1H, d, J=4.4 Hz, Ar), 11.70 (1H, s, OH), 12.54 (1H, s, CO2H); FDMS m/z 237 (M+ +1); Anal. Calcd for C10H8N2O3S: C, 50.84; H, 3.41; N, 11.86. Found: C, 50.77; H, 3.42; N, 11.74.