1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide → (2R,5S,6S)-5-((S)-2-tert-Butoxycarbonylamino-4-methyl-pentanoylamino)-6-hydroxy-2-methyl-azepane-1-carboxylic acid benzyl ester

Beteiligte Stoffe

Reaktionsschritte

1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide (0.164 g, 0.22 mmol) was added to a solution of Boc-Leucine-hydrate (0.190 g, 0.76 mmol), diisopropylethylamine (0.164 g, 0.22 ml, 1.27 mmol), hydroxybenztriazole (0.114 g, 0.83 mmol), and racemic (2R,5S,6S)-5-Amino-6-hydroxy-2-methyl-azepane-1-carboxylic acid benzyl ester (0.27 g, 0.57 mmol) in DMF (3.2 ml). The reaction was stirred overnight at RT, then was diluted with EtOAc (100 ml), washed with H2O (3×50 ml), brine (50 ml), dried with magnesium sulfate, filtered, concentrated in vacuo by rotary evaporation, and chromatographed (silica gel, 50% EtOAc/hexanes) to yield the title compound (0.218 g, 72%): 1H NMR: 7.40-7.29 (m, 5H), 6.75 (1H, bd), 5.12 (2H, AB), 5.0 (1H, bs), 4.15-3.72 (m, 2H), 3.06 (1H, d), 1.60-1.30 (m, 2H), 1.60-1.30 (m, 5H), 1.12 (3H, d), 0.97-0.87(6H, dd); Electrospray mass spec: M+H+=492.0

Herkunft & Nachweise