Hydrochloric Acid → 6-[3-(Dimethylamino)propyl]-9-hydroxy-4-phenylpyrrolo[3,4-c]carbazole-1,3(2H,6H)-dione

Participants

Reaction Conditions

Reaction Steps

To a solution of bromide (204) prepared as described in example 173 (0.12 g, 0.27 mmol) in dimethylacetamide (4 mL) was added the amine, dimethylamine (25 mol eq., 0.85 mL in this case as an 40% aqueous solution). The reaction vessel was sealed and heated at 80° C. with stirring for 18 h, before being diluted with water. The resulting solution was then acidified by the dropwise addition of concentrated hydrochloric acid and the pH was then adjusted to approximately pH=9 by the addition of solid potassium carbonate. The precipitated product was either collected by filtration and washed with water and diisopropyl ether before being dried or extracted with ethyl acetate. The organic layer was dried, the drying agent was removed and the solution was concentrated to dryness. Chromatography on silica eluting with methanol/dichloromethane (1:9 to 1:4), followed by trituration in ethyl acetate/hexane gave amine (208) (52 mg, 47%) as a yellow powder, mp 185–189° C. 1H NMR δ [(CD3)2SO] 11.05 (s, 1H), 9.34 (s, 1H), 8.41 (d, J=2.4 Hz, 1H), 7.78 (s, 1H), 7.64 (m, 2H), 7.56 (d, J=8.9 Hz, 1H), 7.47 (m, 3H), 7.14 (dd, J=8.9, 2.4 Hz, 1H), 4.48 (t, J=6.6 Hz, 2H), 2.16 (t, J=6.5 Hz, 2H), 2.08 (s, 6H), 1.90 (m, 2H). Found: C, 71.98; H, 5.67; N, 10.14. C25H23N3O3.1/4H2O requires: C, 71.84; H, 5.67; N, 10.05.

Provenance & Evidence