Reaktionsschritte
A solution of 29 (1.52 g, 3.87 mmol) in HCl-saturated dioxane (120 mL) was stirred for 100 min (until TLC indicated complete reaction) and the suspension was evaporated. EDCI.HCl (1.48 g, 7.74 mmol) and 5,6,7-trimethoxyindole-2-carboxylic acid (0.97 g, 3.87 mmol) in DMA (12 mL) were added, and the mixture stirred at 20° C. for 16 h. Dilute aq NaHCO3 (100 mL) was added, and the precipitated solid was filtered off, washed with H2O, and dried. Trituration with hot MeOH gave methyl 1-hydroxymethyl-5-nitro-3-[(5,6,7-trimethoxyindol-2-yl)carbonyl]-1,2-dihydro-3H-pyrrolo[3,2-e]indole-7-carboxylate (56) as an orange powder (1.45 g, 71%), mp 239-240.5° C. (dec.). 1H NMR [(CD3)2SO] δ 11.46 (d, J=32 1.6 Hz, 1 H, NH), 11.30 (s, 1 H, NH), 9.19 (s, 1 H, H-4), 7.54 (s, 1 H, H-8), 7.09 (s, 1 H, H-3'), 6.95 (s, 1 H, H-4'), 5.11 (t, J=5.3 Hz, 1 H, OH), 4.71 (t, J=10.1 Hz, 1 H, H-2), 4.47 (dd, J=10.6, 4.1 Hz, 1 H, H-2), 4.02-3.95 (m, 1 H), 3.94 (s, 3 H, OMe), 3.93 (s, 3 H, OMe), 3.82 (s, 3 H, OMe), 3.80 (s, 3 H, OMe), 3.81-3.75 (m, 2 H). Anal. Calculated for C25H24N4O9.1/2H2O: C, 56.3; H, 4.7; N, 10.5. Found: C, 56.4; H, 4.4; N, 10.3%.
