反应详情

60 mg (11 mmol) of ethyl 1-[(R)-2-amino-3-(3,4-dichlorophenyl)propionyl]-4-cyclohexylpiperidine-4-carboxylate and 29 mg (0.12 mmol) of para-nitrophenyl chloroformate are dissolved in 5 ml of dichloromethane. The mixture is stirred for 1 hour at room temperature and the solution is then poured into water and extracted with dichloromethane. The organic phase is dried over sodium sulfate, filtered and concentrated. The colourless oil obtained is diluted in 5 ml of dimethylformamide, the mixture is heated to 80° C., and 18 mg (0.12 mmol) of histamine are added and the solution is stirred for 5 minutes at 80° C. and overnight at room temperature. The reaction is stopped by adding aqueous 1N sodium hydroxide solution and the organic compounds are extracted with dichloromethane. The organic phase is washed with water and then dried over sodium sulfate, filtered and concentrated. The oil obtained is chromatographed on silica gel (eluent: 90/10 DCM/MeOH). 25 mg of ethyl 4-cyclohexyl-1-((R)-3-(3,4-dichlorophenyl)-2-{3-[2-(1H-imidazol-4-yl)ethyl]ureido}-propionyl)piperidine-4-carboxylate in the form of a colourless oil are obtained in a yield of 38%.

1. extractionextracted with dichloromethane
2. dry with materialThe organic phase is dried over sodium sulfate
3. filtrationfiltered
4. concentrationconcentrated
5. customThe colourless oil obtained
6. temperaturethe mixture is heated to 80° C.
7. stirringthe solution is stirred for 5 minutes at 80° C. and overnight at room temperature
8. extractionthe organic compounds are extracted with dichloromethane
9. washThe organic phase is washed with water
10. dry with materialdried over sodium sulfate
11. filtrationfiltered
12. concentrationconcentrated
13. customThe oil obtained
14. customis chromatographed on silica gel (eluent: 90/10 DCM/MeOH)