Reaction Steps
(2S,3S)-tert-butyl 2-((S)-3-(5-chloro-2-methoxyphenyl)-3-fluoro-2-oxo-6-(trifluoromethyl)indoline-1-carboxamido)-3-methylpentanoate (XVIII6): Following general procedure (F), after forming the intermediate, L-isoleucine t-butyl ester hydrochloride (0.342 g, 1.53 mmol) and triethylamine (0.41 mL, 2.92 mmol) were added. After work-up and purification, 0.362 g of the title compound as a white foam solid was obtained (45% yield). mp: 56–60° C. MS: 573 (MH+). Anal. Calcd. for C27H29ClF4N2O5: C, 56.60; H, 5.10; N, 4.89. Found: C, 56.53; H, 5.02; N, 4.80. 1H NMR (CDCl3): 8 0.95–1.02 (m, 6H), 1.26 (m, 1H), 1.51 (s, 9H), 1.55 (m, 1H), 2.05 (m, 1H), 3.55 (s, 3H), 4.54 (dd, J=8.3 Hz, 4.5 Hz, 1H), 6.78 (dd, J=8.8 Hz, 1.3 Hz, 1H), 7.25 (m, 1H), 7.37 (dd, J=8.7 Hz, 2.6 Hz, 1H), 7.43 (d, J=7.8 Hz, 1H), 7.81 (dd, J=2.6 Hz, 1.0 Hz, 1H), 8.60 (s, 1H), 8.73 (d, J=8.1 Hz, 1H). IR (KBr, cm−1): 3338, 2973, 1761, 1736, 1716, 1530, 1491, 1439, 1319, 1261, 1176, 1132, 1061.
