Diisopropylethylamine → tert-butyl(S)-1-((3S,4S)-1-((6-bromo-2-methoxynaphthalen-1-yl)methyl)-4-methyl-5-(2-(methylsulfonyl)acetyl)-2-oxo-2,3,4,5-tetrahydro-1H-benzo[b][1,4]diazepin-3-ylamino)-1-oxopropan-2-yl(methyl)carbamate

Participants

Reaction Steps

A rt solution of tert-butyl(3S,4S)-1-((6-bromo-2-methoxynaphthalen-1-yl)methyl)-4-methyl-5-(2-(methylsulfonyl)acetyl)-2-oxo-2,3,4,5-tetrahydro-1H-benzo[b][1,4]diazepin-3-ylcarbamate (75 mg, 114 μmol) in 4 M HCl in 1,4-dioxane (568 μl) was stirred for 1.5 h then concentrated. This material was taken up in DMF (380 μl) and Boc-N-methyl-L-alanine (25.5 mg, 125 μmol), N,N-diisopropylethylamine (78.9 μl, 456 μmol), and HBTU (47.6 mg, 125 μmol) were added. The reaction was stirred at rt for 20 min, then diluted with EtOAc, washed with sat. aq. NaHCO3 and sat. aq. NaCl, dried over Na2SO4, filtered, and concentrated. The crude material was purified by flash chromatography to provide tert-butyl(S)-1-((3S,4S)-1-((6-bromo-2-methoxynaphthalen-1-yl)methyl)-4-methyl-5-(2-(methylsulfonyl)acetyl)-2-oxo-2,3,4,5-tetrahydro-1H-benzo[b][1,4]diazepin-3-ylamino)-1-oxopropan-2-yl(methyl)carbamate (81 mg, 95%) as a white solid. MS m/z 767/769 (M+Na)+

Provenance & Evidence