Acetic Acid → HCID 70069849, compound

Participants

Reaction Steps

1.5 g of dihydrobromide of the A-isomer of ethyl 3-[1(R)-ethoxycarbonyl-2-{2-(4-piperidyl)ethylthio}ethyl]amino-2-oxo-2,3,4,5-tetrahydro-1H-1-benzazepine-1-acetate obtained in Example 4 is dissolved in 10 ml of water. The resulting aqueous solution is added dropwise to 18 ml of an aqueous solution of 2N sodium hydroxide. After stirring for 1 hour at room temperature, 6 ml of methanol is added, and the system further stirred for 1 hour. After neutralizing the reaction liquid with 7.2 ml of acetic acid, the solvent is distilled off under reduced pressure. After concentration, the residue is purified by HP-20 column chromatography (water:methanol=3:1). The effluent is concentrated under reduced pressure, and the resulting residue is recrystallized from 5 ml of water to give 324 mg of the A isomer of 3-[1(R)-carboxy-2-{2-(4-piperidyl)ethylthio}ethyl]amino-2-oxo-2,3,4,5-tetrahydro-1H-1-benzazepine-1-acetic acid monohydrate as a colorless powder.

Provenance & Evidence