Methyl 3-methoxy-4-(5-nitroindol-3-ylmethyl)benzoate (C) (0.44 g.) was added to a stirred suspension of oil-free sodium hydride (0.031 g.) in dry tetrahydrofuran (10 ml.), under an atmosphere of nitrogen. The dark-red solution was stirred for 10 minutes, and iodomethane (0.18 g.) was added. The mixture was stirred for 30 minutes, and was poured into 1M hydrochloric acid (30 ml.). The mixture obtained was extracted with ethyl acetate (2×50 ml.). The combined extracts were washed with brine (25 ml.), then dried (MgSO4), and evaporated. The yellow oil obtained was purified by flash chromatography on silica gel (50 ml.), eluting with 50:45:5 v/v/v hexane:dichloromethane:ethyl acetate, to give methyl 3-methoxy-4-(1-methyl-5-nitroindol-3-ylmethyl)benzoate (E) (0.33 g., 72%) as a yellow oil, which was crystallized from dichloromethane/hexane to give a yellow solid, m.p. 144°-146° C.; NMR: 3.81(s,3H, N.CH3), 3.83(s,3H, CO.OCH3), 3.92(s,3H, OCH3), 4.11(s,2H, CH2.Ar), 7.27(d,1H), 7.37(s,1H, H2 -indole), 7.49(m,2H), 7.60(d,1H), 8.01(dd,1H, H6 -indole), 8.50(d,1H, H4 -indole).
