反应详情

Method C. Reaction of benzoate 19 (217 mg, 0.53 mmol) and 6 M HCl (5 mL) gave acid 20 (208 mg, 100%) as a white solid: mp (H2O) 268-271° C.; 1H NMR [(CD3)2SO] δ 13.18 (br s, 1 H, CO2H), 8.04 (dd, J=8.6, 1.8Hz, 2 H, H-2, H-6), 7.90 (br dd, J=8.6, 1.8Hz, 2 H, H-3, H-5), 7.81 (ddd, J=8.7, 2.4, 2.0 Hz, 2 H, H-2′, H-6′), 7.70 (ddd, J=8.7, 2.4, 2.0Hz, 2 H, H-3′, H-5′), 4.74 (s, 2 H, CH2SO2), 2.21 (s, 3 H, CH3); MS m/z 393.2 (MH+, 100%), 393.0 (MH+, 35%). Anal. calcd for C18H14ClNO5S: C, 55.18; H, 3.60; N, 3.57. Found: C, 55.22; H, 3.41; N, 3.47%.