Fumaric Acid → (2S,4S,5S)-5-Amino-4-hydroxy-2-isopropyl-6-[4-(2-methoxymethoxyphenyl)-2,2-dimethyl-5-oxopiperazin-1-yl]hexanoic acid (2-carbamoyl-2-methylpropyl)amide hemifumarate

Participants

Reaction Steps

A suspension of 166 mg of {(1S,2S,4S)-4-(2-carbamoyl-2-methylpropylcarbamoyl)-2-hydroxy-1-[4-(2-methoxymethoxyphenyl)-2,2-dimethyl-5-oxopiperazin-1-ylmethyl]-5-methylhexyl}carbamic acid benzyl ester obtained in the above reaction (0.24 mmol) and 83 mg of 10% palladium-carbon (50% wet) in ethanol (3 ml) was stirred under a hydrogen atmosphere at room temperature for two hours. Hydrogen in the reaction vessel was replaced by nitrogen. Then, palladium-carbon was separated by filtration and washed with ethanol. The solvent was evaporated from the filtrate under reduced pressure, and the residue was purified by silica gel column chromatography (elution solvent:methylene chloride/methanol/triethylamine=200/20/1). 10.8 mg of fumaric acid (0.093 mmol) was added to a solution of 102 mg of (2S,4S,5S)-5-amino-4-hydroxy-2-isopropyl-6-[4-(2-methoxymethoxyphenyl)-2,2-dimethyl-5-oxopiperazin-1-yl]hexanoic acid (2-carbamoyl-2-methylpropyl)amide obtained above (0.18 mmol) in methanol (3 ml), and the mixture was stirred at room temperature for five minutes. The solvent was evaporated under reduced pressure to obtain 99 mg of the title compound (yield: 66%).

Provenance & Evidence