Hydrochloric Acid → 9-Bromo-5-(2-benzimidazolylmethyl)-6,7-dihydro-1H, 5H-pyrido[1,2,3-de]quinoxaline-2,3-dione hydrochloride

Participants

Reaction Conditions

Reaction Steps

A solution of 9-bromo-5-(o-aminophenylcarbamoylmethyl)-6,7-dihydro-1H, 5H-pyrido[1,2,3-de]quinoxaline-2,3-dione (Example 99) (250 mg, 0.5 mmol) in a mixture of acetonitrile (10 mL) and concentrated hydrochloric acid (2 mL) was heated at 50° C. for 5 h and concentrated. The residue was washed with distilled water and diethyl ether and dried in vacuo to give 150 mg of the title compound (73%): mp>270° C.; 1H NMR (270 MHz, DMSO-d6) δ12.15 (s, 1H), 7.80 (dd, 2H, J=6.3, 3 Hz), 7.54 (dd, 2H, J=6.3, 3 Hz), 7.28 (bs, 1H), 7.25 (bs, 1H), 5.26~5.35 (m, 1H), 3.41~3.50 (m, 2H), 3.07 (ddd, 1H, J=17.1, 13.5, 4.5 Hz), 2.90 (dm, 1H, J=17.1 Hz), 2.19 (dm, 1H, J=13.5 Hz), 1.90~2.05 (m, 1H).

Provenance & Evidence