反应详情

4-({Cyclohexyl[1-(3-ethoxyphenyl)-3-ethyl-1H-pyrazol-4-yl]methyl}amino)benzoic acid (0.18 g) synthesized in the above-mentioned (2) was dissolved in N,N-dimethylformamide (3 mL), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (0.11 g), 1-hydroxybenzotriazole.monohydrate (0.09 g) and methyl 3-amino-2-methylpropanoate (0.07 g) were added at room temperature, and the mixture was stirred overnight. Water was added to the reaction mixture, and the mixture was extracted with diethyl ether. The extract was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:1, volume ratio) to give methyl 3-({[4-({cyclohexyl[1-(3-ethoxyphenyl)-3-ethyl-1H-pyrazol-4-yl]methyl}amino)phenyl]carbonyl}amino)-2-methylpropanoate (0.03 g) as a yellow oil. This was dissolved in ethanol (2.0 mL), 1N aqueous sodium hydroxide solution (0.5 mL) was added at room temperature, and the mixture was stirred at room temperature for 0.5 hr. Ethanol was evaporated under reduced pressure, and 1N hydrochloric acid (0.5 mL) was added to the residue. The precipitate was washed with water to give the title object compound (0.02 g, 9%) as a colorless solid.

1. extractionthe mixture was extracted with diethyl ether
2. concentrationThe extract was concentrated under reduced pressure
3. customthe residue was purified by silica gel column chromatography (ethyl acetate:hexane=1:1, volume ratio)