“…Filtration followed by concentration in vacuo and recrystallization from ethyl acetate/hexane gave 235 mg (80%) of 23. An analytical sample was obtained by a second recrystallization from ethyl acetate/hexane: mp 143-143.5 °C; NMR (DMSO-de) ó 1.21 (d, =7 = 6.5 Hz, 6H), 3.41 (heptet, =7 = 6.5 Hz, 1H), 3.87 (s, 3H), 7.18 (dd, =7 = 9, 2.5 Hz, 1H), 7.42 5-Methoxy-3-(phenylthio)benzo[b]thiophene-2-carboxamide (24). Thiophenol (116 «L, 1.13 mmol) was added to a suspension of 22 (250 mg, 1.03 mmol) in 2 mL of dimethylformamide.…”