Reacción #5077

Ecuación de reacción

N-hydroxy-succinimide

Ac-Ala-OH

H-Lys(Boc)-OH

H-Lys(Boc)-OH

sodium hydroxide

hydrochloric acid

Ac-Ala-OH

triethylamine

→

Ac-Ala-Lys(Boc)-OH

Disolventes

dioxane

Condiciones de reacción

Tratamiento posterior

1. 1
   Otroprepared by the method of Anderson et al., J
2. 2
   workup.DISSOLUTIONdissolved in a solution
3. 3
   ConcentraciónSufficient dry sodium chloride to nearly saturate the solution
4. 4
   workup.ADDITIONwas added
5. 5
   ExtracciónThe product was extracted into ethyl acetate and it
6. 6
   Lavadowas washed with 0.2N hydrochloric acid
7. 7
   Otroprepared in saturated aqueous sodium chloride
8. 8
   SecadoThe organic phase was dried over anhydrous sodium sulfate
9. 9
   Filtraciónfiltered
10. 10
    OtroSolvent was removed by evaporation
11. 11
    OtroThe product was crystallized from ethyl acetate
12. 12
    Otrohexane to yield 7.3 g (mp 86°-89°)

Procedimiento

Ac-Ala-Lys(Boc)-OH was prepared by coupling the N-hydroxysuccinimide ester of Ac-Ala-OH, prepared by the method of Anderson et al., J. Am. Chem. Soc. 86: 1839, (1964), to H-Lys(Boc)-OH. The N-hydroxy-succinimide of Ac-Ala-OH (6.25 g, 27.4 mmoles) was dissolved in 30 mL of dioxane and was added to a solution of H-Lys(Boc)-OH (7.50 g, 30.4 mmoles) dissolved in a solution consisting of 30 mL of 1.0N sodium hydroxide and triethylamine (2.12 mL, 15.0 mmoles). The reaction mixture was stirred overnight, then acidified with hydrochloric acid. Sufficient dry sodium chloride to nearly saturate the solution was added. The product was extracted into ethyl acetate and it was washed with 0.2N hydrochloric acid prepared in saturated aqueous sodium chloride. The organic phase was dried over anhydrous sodium sulfate and filtered. Solvent was removed by evaporation. The product was crystallized from ethyl acetate:hexane to yield 7.3 g (mp 86°-89°).

Fuente