Formic Acid → 4-(Methylamino)quinazoline-2-thiol

Participants

Reaction Steps

A mixture of 2-chloro-N-methylquinazolin-4-amine (Example 39) (100 mg, 0.52 mmol), thiourea (47.5 mg, 0.62 mmol) and formic acid (0.02 mL, 0.52 mmol) in ethanol (5 mL) was refluxed for 1.5 h. After cooling to room temperature, the reaction mixture was neutralized with diluted NaOH aqueous solution. The solvent was removed under vacuum and the residue was purified by preparative HPLC eluting with acetonitrile and water to give the title compound (18 mg, 18%). 1H NMR (400 MHz, DMSO-d6) δ 2.99 (d, J=4.8 Hz, 3H), 7.25 (t, J=7.6 Hz, 1H), 7.35 (d, J=8.0 Hz, 1H), 7.65-7.61 (m, 1H), 8.0 (d, J=8.0 Hz, 1H), 8.70 (d, J=4.4 Hz, 1H), 12.32 (s, 1H). MS 192 (MH+).

Provenance & Evidence