Reaction Steps
Under dry conditions, a mixture of methyl-(2-methyl-4,5-dihydro-thiazolo[4,5-h]quinazolin-8-yl)-(3-nitro-phenyl)-amine (16 mg, 0.045 mmol) and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) (10.2 mg, 0.045 mmol) in dry toluene (2 mL) was heated under reflux for 16 h. The solvent was evaporated under vacuum and the residue was purified by flash column chromatography (10% EtOAc:hexane) to afford the title product as a yellow solid (10 mg, 68%). mp 209-210° C. Anal. RP-HPLC: tR 23.4 min (10-70% MeCN, purity 98%). 1H-NMR (CDCl3): δ 9.09 (s, 1H, Py-H), 8.41 (t, 1H, J 2.3, Ph-H), 8.09 (ddd, 1H, J 8.2, 2.3, 1.0, Ph-H), 7.85 (d, 1H, J 8.7, Ph-H), 7.79 (ddd, 1H, J 8.2, 2.3, 1.0, Ph-H), 7.72 (d, 1H, J 8.7, Ph-H), 7.58 (t, 1H, J 8.2, Ph-H), 3.78 (s, 3H, N—CH3), 2.94 (s, 3H, Me). 13C-NMR (CDCl3): δ 171.04, 161.09, 158.53, 157.16, 148.54, 148.04, 146.25, 131.74, 129.31, 125.29, 121.01, 119.85, 119.30, 116.97, 38.39, 20.48 missing 1 quat signal. MS (ESI+): m/z 352.08 (M+H)+.
