反应详情

A mixture of 2-methyl-7-oxo-4,5,6,7-tetrahydro-benzothiazole-6-carbaldehyde (200 mg, 1.02 mmol), N-(4-trifluoromethyl-phenyl)-guanidine nitrate (273 mg, 1.02 mmol), NaOH (41 mg, 1.02 mmol) and 2-methoxyethanol (1.25 mL) was heated under reflux for 16 h. The reaction mixture was concentrated under vacuum. Flash column chromatography (20% EtOAc:hexane) followed by crystallisation from EtOAc gave the pure title compound as a white crystalline solid (30 mg, 8%): mp 212-213° C. Anal. RP-HPLC: tR 21.8 min (10-70% MeCN, purity 95%). 1H-NMR (CDCl3): δ 8.17 (s, 1H, Py-H), 7.71 (d, 2H, J 8.4, Ph-H), 7.52 (d, 2H, J 8.4, Ph-H), 7.16 (s, 1H, NH), 3.04 (t, 2H, J 6.6, CH2), 2.94 (t, 2H, J 6.6, CH2), 2.72 (s, 3H, CH3). MS (ESI−): m/z 360.95 (M−H)+.

1. temperaturewas heated
2. temperatureunder reflux for 16 h
3. concentrationThe reaction mixture was concentrated under vacuum
4. customFlash column chromatography (20% EtOAc:hexane) followed by crystallisation from EtOAc