反应详情

3-Butanoyloxyhexanoic acid (234 mg) prepared by the method described in Preparation 6-(2) and N-hydroxysuccinimide (133 mg) was dissolved in dioxane (3 ml). N,N'-Dicyclohexylcarbodiimide (239 mg) was added thereto under ice cooling. The mixture was reached to room temperature and stirred at ambient temperature over night. The crystallized N,N'-dicyclohexyl urea was filtered off and the filtrate was concentrated to give a residue which was dissolved in N,N-dimethylformamide (5 ml). To this solution was added a solution of N-glycyl-L-serine (324 mg) and triethylamine (280 μl) in water (3 ml) at 0° C. The resulting mixture was reached to room temperature and stirred at ambient temperature overnight. The reaction mixture was acidified with 1 N hydrochloric acid, extracted with ethyl acetate, washed with water and dried over magnesium sulfate. Ethyl acetate was distilled off to give a residue which was subjected to preparative thin layer chromatography (Merck, 0.25 mm×5) and eluted with a mixture of benzene, dioxane and acetic acid (10:5:1). The band containing the object compound was extracted with a mixture of methanol and chloroform (3:7) and the solvent was evaporated off under reduced pressure to afford a wax of N-[N-(3-butanoyloxyhexanoyl)glycyl]-L-serine.

1. customdescribed in Preparation 6-(2)
2. customwas reached to room temperature
3. filtrationThe crystallized N,N'-dicyclohexyl urea was filtered off
4. concentrationthe filtrate was concentrated
5. customto give a residue which
6. customwas reached to room temperature
7. stirringstirred at ambient temperature overnight
8. extractionextracted with ethyl acetate
9. washwashed with water
10. dry with materialdried over magnesium sulfate
11. distillationEthyl acetate was distilled off
12. customto give a residue which
13. washeluted with a mixture of benzene, dioxane and acetic acid (10:5:1)
14. additionThe band containing the object compound
15. extractionwas extracted with a mixture of methanol and chloroform (3:7)
16. customthe solvent was evaporated off under reduced pressure