Following the procedure described for the preparation of 4-methoxy-N-((1S)-1-{[((1S)-3-methoxy-2-oxo-1-{[(3S)-2-oxopyrrolidin-3-yl]methyl}propyl)amino]carbonyl}-4-methylpentyl)-1H-indole-2-carboxamide but substituting N1-((1S)-3-hydroxy-2-oxo-1-{[(3S)-2-oxopyrrolidin-3-yl]methyl}propyl)-4-methyl-N2-[(2R)-tetrahydrofuran-2-ylcarbonyl]-l-leucinamide and making noncritical variations provided a crude product. This material was purified by radial chromatography (1 mm plate, 95:5 dichloromethane/methanol, sample loaded in dichloromethane) resulting in the isolation of 45.6 mg (22%) of the title compound as a light orange gum and as a mixture of diastereomers. Rf = 0.30 (95:5 dichloromethane/methanol); 1H NMR (400 MHz, DMSO-d6, major diastereomer) δ 8.33 (d, J = 8 Hz, 1H), 7.70 (d, J = 9 Hz, 1H), 7.66 (s, 1H), 4.39–4.28 (m, 2H), 4.24–4.07 (m, 3H), 3.94–3.86 (m, 1H), 3.75 (q, J = 7 Hz, 1H), 3.24 (s, 3H), 3.18–3.06 (m, 2H), 2.27–2.15 (m, 1H), 2.14–2.03 (m, 2H), 1.92–1.73 (m, 4H), 1.67–1.53 (m, 4H), 0.88 (s, 9H); MS (ESI+) for C21H35N3O6m/z 426 (M + H). HRMS (ESI+) calcd for C21H35N3O6+H1 426.2599, found 426.2604.