Diisopropylethylamine → N2-(3-{[(9H-fluoren-9-ylmethoxy)carbonyl]amino}-2,2-dimethylpropanoyl)-N-[(3R,4S,5S)-3-methoxy-1-{(2S)-2-[(1R,2R)-1-methoxy-2-methyl-3-oxo-3-{[(1S)-2-phenyl-1-(1,3-thiazol-2-yl)ethyl]amino}propyl]pyrrolidin-1-yl}-5-methyl-1-oxoheptan-4-yl]-N-methyl-L-valinamide

Participants

Reaction Steps

To #86 (100 mg, 0.152 mmol, 1 eq.) in dichloromethane (4 mL, 0.038 M) and N,N-dimethylformamide (0.5 mL) was added #93 (51.6 mg, 0.152 mmol, 1 eq.) followed by diisopropylethylamine (80.0 μL, 0.457 mmol, 3 eq.) and HATU (89.8 mg, 0.229 mmol, 1.5 eq.). The reaction was stirred for 18 hours and then concentrated in vacuo. The residue was taken up in ethyl acetate (6 mL) and was washed with 1 M aqueous hydrochloric acid solution (2×2 mL) and with brine. The organic layer was dried over sodium sulfate, filtered, and concentrated in vacuo. The residue was taken up in dichloromethane (250 mL) and filtered; the filtrate was concentrated in vacuo onto silica and purified by silica gel chromatography (Gradient: 0% to 50% acetone in heptane) to provide #94 (90 mg, 60%) as a white solid. LC-MS: m/z 979.8 [M+H+], 1002.7 [M+Na+], retention time=1.15 minutes; 1H NMR (400 MHz, DMSO-d6), presumed to be a mixture of rotamers, characteristic product signals: δ [8.64 (br d, J=8.6 Hz) and 8.86 (br d, J=8.6 Hz), total 1H], 7.86-7.91 (m, 2H), [7.77 (d, J=3.3 Hz) and 7.79 (d, J=3.3 Hz), total 1H], 7.67-7.73 (m, 2H), [7.63 (d, J=3.3 Hz) and 7.65 (d, J=3.3 Hz), total 1H], 6.87-6.95 (m, 1H), [5.39 (ddd, J=11, 8, 4 Hz) and 5.52 (ddd, J=11.5, 9, 4 Hz), total 1H], [4.44 (dd, J=8.4, 8.4 Hz) and 4.55 (dd, J=8.4, 8.4 Hz), total 1H], 3.16, 3.20, 3.21 and 3.25 (4 s, total 6H), 2.96 and 3.06 (2 br s, total 3H), 0.69-0.77 (m, 3H).

Provenance & Evidence