[Synthesis]
General procedure for the synthesis of 4-(pyridin-4-yl)-N-(m-tolyl)thiazol-2-amine (STF-62247) from m-tolyl-2-thiourea and 4-(bromoacetyl)pyridine hydrobromide: A mixture of 4-(bromoacetyl)pyridine hydrobromide (1.13 g, 4.03 mmol) and m-tolyl-2-thiourea (0.67 g, 4.03 mmol) in A mixture in ethanol (20 mL) was stirred at reflux temperature for 3 hours. Upon completion of the reaction, the mixture was cooled to 20 °C, diluted with water (50 mL), and the pH was adjusted with ammonia to about 5. Subsequently, the mixture was stirred at 20 °C for 2 hours. The precipitate was collected by filtration, washed with water (5 mL) and dried. The crude product was purified by column chromatography using gradient elution (50-100% ethyl acetate/petroleum ether) to afford the target compound STF-62247 (0.94 g, 87% yield) as a cream colored powder. Melting point (ethyl acetate/petroleum ether) 158-160°C. 1H NMR (δ): 10.27 (br s, 1H, NH), 8.62 (dd, J = 4.6, 1.6 Hz, 2H, H-2', H-6'), 7.84 (dd, J = 4.6, 1.6 Hz, 2H, H-3', H-5'), 7.69 (s, 1H, H-5) , 7.57 (br d, J = 7.9 Hz, 1H, H-6"), 7.47 (br s, 1H, H-2"), 7.24 (dd, J = 7.8, 7.5 Hz, 1H, H-5"), 6.81 (br d, J = 7.5 Hz, 1H, H-4"), 2.33 (s, 3H, CH3).13C NMR (δ): 163.5 , 150.1 (2), 147.6, 140.9, 140.8, 138.1, 128.8, 122.2, 119.8 (2), 117.5, 114.1, 107.2, 21.2. mass spectrum (MS) m/z: 268.4 (MH+, 100%). Elemental analysis (C15H13N3S-0.25H2O) Calculated values: C, 66.27; H, 5.01; N, 15.46. Measured values: C, 64.48; H, 5.08; N, 15.08%. |