反应详情

3-(3,5-Dibromo-4-(4-methoxybenzyloxy)phenyl)-N-(3-(trifluoromethyl)benzyl)-1,2,4-oxadiazole-5-carboxamide (128 mg, 0.2 mmol) was dissolved in dimethylformamide (2 mL) and sodium-tert-butoxide (21 mg, 0.22 mmol) was added in one portion followed by ethyl iodide (34 mg, 0.22 mmol). The mixture was stirred at room temperature for 20 h and was then treated with water (8 mL) and extracted with ethyl acetate (4 mL). The extract was evaporated to dryness and the residue was dissolved in dichloromethane (2 mL), trifluoroacetic acid (0.2 mL) was added and the solution was allowed to stand for 1 h. Methanol (0.5 mL) was added, the solution was evaporated to dryness and the residue was purified by preparative HPLC to give the title compound (32.8 mg, 32%) as a colourless solid. 1H NMR δ (ppm) (DMSO-d6): 1.14 and 1.29 (3H, two t), 3.47 and 3.62 (2H, two q), 4.88 and 4.97 (2H, two s), 7.60-7.75 (3H, m), 7.78 and 7.89 (1H, two s), 8.04 and 8.15 (2H, two s), 10.9 (1H, s, br). LCMS (10 cm_apci_formic) tR 4.33 min; m/z 546/548/550 [M−H]−.

1. extractionextracted with ethyl acetate (4 mL)
2. customThe extract was evaporated to dryness
3. dissolutionthe residue was dissolved in dichloromethane (2 mL)
4. additiontrifluoroacetic acid (0.2 mL) was added
5. waitto stand for 1 h
6. additionMethanol (0.5 mL) was added
7. customthe solution was evaporated to dryness
8. customthe residue was purified by preparative HPLC