Reaction Steps
A mixture of quindoline (2.0 g, 9.2 mmol) from Example 2, methanol (5 mL) and methyl iodide (880 mL, 14.1 mmol) was heated in a bomb at 120° C. for 4 hours. After cooling, the resulting brown precipitate (2.5 g, 75.5%) was filtered and washed with ether. Recrystallization from water gave the title compound as bright yellow crystals, yield 50%, mp 283.5°-284° C. [lit 284°-286° C. (Gellert, E.; Raymond-Hamet; Schlittler, E. Helv. Chim. Acta 1951, 34, 642-651)]; 1H NMR (DMSO-d6) δ 12.87 (s, 1H, NH), 9.28 (s, 1H, H11), 8.79 (d, J=8.4, 1H, H6), 8.75 (d, J=9.2, 1H, H4), 8.57 (d, J=8.3, 1H, H1), 8.16 (t, J=7.6, 1H, H3), 7.94-7.92 (dd, J=7.2, J=7.0, 2H, H2 and H8), 7.82 (d, J=8.4, 1H, H9), 7.51 (t, J=7.0, 1H, H7), 5.02 (s, 3H, NCH3); 13C NMR (DMSO-d6) δ 145.62, 137.97, 135.25, 133.87, 133.16, 132.34, 129.76, 126.99, 126.21, 126.13, 124.72, 121.31, 117.78, 113.76, 113.10, 40.19; MS (EI, m/z) 232.1 (M+) .
