反应详情

A mixture of 3-guanidinobenzoic acid (Example C) (179.5 mg, 1.00 mmol), (S)-ethyl 3-(2-aminoacetamido)-3-(3-bromo-5-tert-butyl)phenyl)propanoate hydrochloride (Example H) (439.5 mg, 1.00 mmol) and 1-hydroxybenzotriazole hydrate (31.2 mg, 0.20 mmol) was dissolved in DMF (4 mL) and dichloromethane (4 mL) and stirred at room temperature under nitrogen atmosphere for 10 min to give a colorless suspension. N,N′-diisopropylcarbodiimide (205 uL, 1.33 mmol) was added and the reaction mixture was stirred at room temperature under nitrogen atmosphere overnight. The solvent was evaporated in vacuo to give a yellow viscous residue of the intermediate product: (S)-ethyl 3-(3-bromo-5-(tert-butyl)phenyl)-3-(2-(3-guanidinobenzamido)acetamido) propanoate. LC-MS analysis of the crude residue shows the desired product's mass: m/z 546 (79BrM+H), m/z 548 (81BrM+H); m/z 568 (79BrM+Na) and m/z 570 (81BrM+Na); Calcd for C25H32BrN5O4: 546.46. The crude residue will be used as such for the saponification (step #2).

1. customto give a colorless suspension
2. customThe solvent was evaporated in vacuo
3. customto give a yellow viscous residue of the intermediate product