Diisopropylethylamine → N-[(9H-fluoren-9-ylmethoxy)carbonyl]-N-methyl-L-valyl-N-{(3R,4S,5S)-3-methoxy-1-[(2S)-2-{(1R,2R)-1-methoxy-2-methyl-3-[(2-phenylethyl)amino]-3-thioxopropyl}pyrrolidin-1-yl]-5-methyl-1-oxoheptan-4-yl]-N-methyl-L-valinamide

Participants

Reaction Steps

To a mixture of #23 (337 mg, 0.983 mmol, 1 eq.) in dichloromethane (8 mL, 0.1 M) and N,N-dimethylformamide (1 mL) were added #8 (564 mg, 0.885 mmol, 0.9 eq.), diisopropylethylamine (383 mg, 2.95 mmol, 3 eq.) and HATU (472 mg, 1.18 mmol, 1.2 eq.). After 2 hours, the mixture was diluted with dichloromethane, washed sequentially with 0.1 M aqueous hydrochloric acid and with brine, dried over magnesium sulfate, filtered, and concentrated in vacuo. The residue was purified by reverse phase chromatography (Method G) to give #35 (600 mg, 66%); LC-MS: m/z 926.6 [M+H+], retention time=1.16 minutes; 1H NMR (400 MHz, DMSO-d6), presumed to be a mixture of rotamers, characteristic signals: δ [9.94 (br t, J=5 Hz) and 10.16-10.23 (br m), total 1H], 7.90 (d, J=7.2 Hz, 2H), [7.71 (br d, J=7 Hz) and 8.06 (br d, J=8 Hz), total 1H], 7.60-7.65 (m, 2H), 7.41 (br dd, J=7, 7 Hz, 2H), 7.15-7.36 (m, 7H), 3.29 (s, 3H), 1.16-1.22 (m, 3H).

Provenance & Evidence