反应详情

In 8 ml of dimethylformamide (DMF) were dissolved 898 mg of benzyloxycarbonyl-L-phenylalanine and 2.05 g of Nδ,Nω -dibenzyloxycarbonyl-L-arginine 1-naphthyl ester trifluoroacetate, and to the resulting solution were added 681 mg of dicyclohexylcarbodiimide (DCC), 405 mg of 1-hydroxybenzotriazole (HOBt) and 304 mg of triethylamine (TEA) with ice-cooling and with stirring, after which the mixture was stirred for 3 hrs at the same temperature. The temperature was elevated to room temperature and the mixture was stirred for a further 24 hrs. After the reaction, the crystals of dicyclohexylurea (DCU) precipitated were removed by filtration, and ethyl acetate was added to the filtrate, after which the mixture was washed with 10% aqueous citric acid solution, saturated sodium bicarbonate solution and saturated sodium chloride solution in this order, dried over anhydrous magnesium sulfate, and thereafter evaporated under reduced pressure to removed the solvent. The white powder thus precipitated was collected and recrystallized from chloroform-diethyl ether to obtain 1.1 g (yield 43%) of benzyloxycarbonyl-L-phenylalanyl-Nδ,Nω -dibenzyloxycarbonyl-L-arginine 1-naphthyl ester, m.p. 125°-130° C.

1. temperaturecooling
2. stirringafter which the mixture was stirred for 3 hrs at the same temperature
3. customwas elevated to room temperature
4. stirringthe mixture was stirred for a further 24 hrs
5. customAfter the reaction
6. customthe crystals of dicyclohexylurea (DCU) precipitated
7. customwere removed by filtration, and ethyl acetate
8. additionwas added to the filtrate
9. washafter which the mixture was washed with 10% aqueous citric acid solution, saturated sodium bicarbonate solution and saturated sodium chloride solution in this order
10. dry with materialdried over anhydrous magnesium sulfate
11. customevaporated under reduced pressure
12. customto removed the solvent
13. customThe white powder thus precipitated
14. customwas collected
15. customrecrystallized from chloroform-diethyl ether