Diisopropylethylamine → (2R,4R)-5-(4-Bromophenyl)-2-hydroxy-4-[(3-hydroxy-3H-benzotriazole-5-carbonyl)-amino]-pentanoic Acid Ethyl Ester

Participants

Reaction Steps

HCTU (837 mg, 2.0 mmol) was added to a solution of 1-hydroxy-1H-1,2,3-benzotriazole-6-carboxylic acid (362 mg, 2.0 mmol) and the mixture was stirred at room temperature for 10 minutes. DIPEA (529 μL, 3.0 mmol) and (2R,4R)-4-amino-5-(4-bromophenyl)-2-hydroxy-pentanoic acid ethyl ester (320 mg, 1.0 mmol) were then added and the resulting mixture was stirred at room temperature for 15 minutes. The mixture was concentrated in vacuo and the resulting residue was purified (C18 column, 55 g, 20-70% MeCN in water with 5% TFA) to yield the title compound as a white solid 365 mg).

Provenance & Evidence