Hexanoyl chloride (0.024 g.) was added to a stirred solution of methyl 4-(5-aminobenzo[b]thien-3-ylmethyl)-3-methoxybenzoate (H) (0.06 g.), and N-methylmorpholine (0.1 ml.) in dichloromethane (3 ml.). The mixture was stirred for 1 hour and then poured into water (20 ml.). The aqueous mixture was extracted with dichloromethane (2×20 ml.). The combined extracts were dried (MgSO4), and evaporated. The mixture was recrystallized from a mixture of ethyl acetate and hexane to give the title compound (0.05 g., 75%) as a colorless solid; NMR (250 MHz, DMSO-d6): 0.87(t,3H, CH2CH3), 1.28(m,4H, CH2.CH2.CH3), 1.59 (quintet,2H, CH2CH2CON), 2.29(t,2H, CH2CON), 3.84(s, 3H, OCH3), 3.91(s,3H, OCH3), 4.11(s,2H, CH2 --Ar), 7.14 (d,1H), 7.34(s,1H), 7.49(m,3H), 7.86(d,1H), 8.11(d, 1H), 9.95(s,1H).
