反应详情

Under ice-cooling, 1.03 ml of ethyl chlorocarbonate was added dropwise to a mixed solution of 2.45 g of 2-[3-cycloheptyl-3-(4-dimethylaminophenyl)ureido]-4-methoxy-6-tertbutylphenol, 1.51 ml of triethylamine and 50 ml of dichloromethane, and the mixture was stirred at room temperature for 2 hours. After washing and drying, the solvent was removed under reduced pressure and the residue was purified by silica gel column chromatography (solvent; chloroform:ethyl acetate=20:1), and precipitated crystals were recrystallized from a mixed solution of isopropyl ether and ethyl acetate. The resulting crystals were dissolved in 50 ml of dichloromethane, and 2 ml of a 4N hydrogen chloride-dioxane solution was added thereto. The mixture was evaporated to dryness under reduced pressure. The residue was crystallized from an isopropyl ether solution to give 1.34 g of O-ethoxycarbonyl-2-[3-cycloheptyl-3-(4-dimethylaminophenyl)ureido]-4-methoxy-6-tert-butylphenol hydrochloride (yield: 44%, melting point: 163°-167° C. (decomposed)).

1. temperatureUnder ice-cooling
2. washAfter washing
3. customdrying
4. customthe solvent was removed under reduced pressure
5. customthe residue was purified by silica gel column chromatography (solvent; chloroform:ethyl acetate=20:1)
6. customprecipitated crystals
7. customwere recrystallized from a mixed solution of isopropyl ether and ethyl acetate
8. dissolutionThe resulting crystals were dissolved in 50 ml of dichloromethane
9. addition2 ml of a 4N hydrogen chloride-dioxane solution was added
10. customThe mixture was evaporated to dryness under reduced pressure
11. customThe residue was crystallized from an isopropyl ether solution