[CH3:1][O:2][C:3]1[CH:8]=[C:7]([N+:9]([O-])=O)[CH:6]=[CH:5][C:4]=1[C:12]1[S:16][C:15]([CH3:17])=[N:14][C:13]=1[CH3:18]>C(O)C>[CH3:17][C:15]1[S:16][C:12]([C:4]2[CH:5]=[CH:6][C:7]([NH2:9])=[CH:8][C:3]=2[O:2][CH3:1])=[C:13]([CH3:18])[N:14]=1A suspension of 5-(2-methoxy-4-nitro-phenyl)-2,4-dimethyl-thiazole (415 mg, 1.57 mmol) and anhydrous stannous chloride (1.52 g, 7.85 mmol) in ethanol (25 mL) was stirred at reflux for 3 hours. The yellow solution was evaporated and the residue dissolved in ethyl acetate. This solution was washed with 1N aqueous sodium hydroxide solution, twice with water, with brine, dried with magnesium sulfate and the solvent was evaporated to dryness. Column chromatography (50 g silica, heptane/ethyl acetate 30-60% v/v) afforded the title compound (276 mg, 75%) as a pale yellow solid. MS ISP (m/e): 235.2 [(M+H)+]. 1H NMR (CDCl3, 300 MHz): δ (ppm)=7.04 (d, 1H), 6.31 (m, 2H), 3.80 (s broad, 2H), 3.78 (s, 3H), 2.66 (s, 3H), 2.29 (s, 3H). Mp 112-115° C.
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