The product of Step 2 (2.0 g, 4.98 mmol) was dissolved in anhydrous N,N-dimethylformamide (10 ml). To this solution was added potassium carbonate (1.72 g, 12.44 mmol) and iodomethane (0.847 g, 5.97 mmol), and the reaction mixture was sealed in a pressure flask and stirred for 12 hours at room temperature, then diluted with water and ethyl acetate (20/70 ml). The aqueous solution was then extracted with ethyl acetate (3×20 ml). The organic layers were combined, washed with water (1×100 ml), dried over magnesium sulfate, filtered and concentrated to give the title compound (1.58 g, 77.5%). 1H NMR (CDCl3, 300 MHz): δ 7.43-7.28 (m, 7 H), 6.68 (d, 1H, J=8.1 Hz), 5.15-5.05 (m, 3H), 3.38 (s, 3H), 2.45 (d, 3H, 1.5 Hz) ppm.
