To a stirred solution of methyl (S)-3-oxo-8-[3-(pyridin-2-ylamino)-1-propyloxy]-2-(2,2,2-trifluoroethyl)-2,3,4,5-tetrahydro-1H-2-benzazepine-4-acetate (19.50 g, 42 mmol) in dioxane (150 mL) was added aqueous 1 N NaOH (75 mL, 75 mmol). The cloudy reaction was stirred at RT for 2 h, then the resulting homogeneous solution was neutralized with aqueous 1 N HCl (75 mL, 75 mmol). The solution was concentrated to near dryness by rotary evaporation to precipitate out the product. The supernatant was decanted off and the remaining gummy solid was redissolved in methanol. The clear solution was then reconcentrated by rotary evaporation. The remaining solid was triturated with a small volume of water, filtered and dried under vacuum to give the title compound (16.38 g, 86%) as a white powder. HPLC (Hamilton PRP-1®, 25% CH3CN/H2O containing 0.1% TFA) k′=3.1; [α]D−112.3° (c, 1.0, MeOH); MS (ES) m/e 452.3 (M+H)+; 1H NMR (400 MHz, DMSO-d6) δ 7.95 (dd, 1H), 7.34 (dt, 1H), 7.02 (d, J=9.2 Hz, 1H), 6.81 (m, 2H), 6.58 (t, 1H), 6.47 (m, 2H), 5.30 (d, J=16.5 Hz, 1H), 4.27-4.13 (m, 2H), 4.15 (d, J=16.5 Hz, 1H), 4.02 (t, 1H), 3.78 (m, 1H), 3.37 (m, 2H), 3.00 (dd, 1 H), 2.69 (dd, 1H), 2.65 (dd, 1H), 2.41 (dd, 1H), 1.96 (ddd, 2 H). Anal. Calcd for C22H24F3N3O4: C, 58.53; H, 5.36; N, 9.31. Found: C, 58.37; H, 5.42; N, 9.20.
