Diisopropylethylamine → methyl N-[(2R,3R)-3-{(2S)-1-[(3R,4S,5S)-4-{[N-(3-{[(9H-fluoren-9-ylmethoxy)carbonyl]amino}-2,2-dimethylpropanoyl)-L-valyl] (methyl)amino}-3-methoxy-5-methylheptanoyl]pyrrolidin-2-yl}-3-methoxy-2-methylpropanoyl]-L-phenylalaninate

Participants

Reaction Steps

To a stirring solution of #114 (200 mg, 0.316 mmol, 1.00 eq.) in 2 mL of dichloromethane, #124 (107 mg, 0.316 mmol, 1.00 eq.) was added followed by Hunig's base (0.167 mL, 0.948 mmol, 3.00 eq.) and HATU (149 mg, 0.379 mmol, 1.20 eq.). The reaction was allowed to stir at room temperature for ˜12 hours. The reaction was concentrated to a smaller volume, taken up in 10 mL of ethyl acetate, and washed two times with 5 mL of 1M HCl, and once with 5 mL of brine. The organic layer was dried over sodium sulfate and decanted. Organics where concentrated in vacuo and the crude material was taken up in dichloromethane. The precipitate was filtered. The organic layer was concentrated in vacuo and the residue was purified by silica chromatography (Gradient: 0%-50% acetone in heptane) producing #125 (235 mg, 78%) as a white solid. LC-MS (Protocol Q): m/z 954.2 [M+H+] retention time=2.28 minutes.

Provenance & Evidence