Reaction #1552039

Reaction equation

trifluoroacetic acid

N-palmitoyloxy-glycyloxysuccinimide

L-histidine

triethylamine

→

colorless solid

Yield 54.0%

N-palmitoyl-Gly-His TFA

Yield 54.0%

Solvents

DMF

water

Conditions

Workup

1. 1
   Temperaturewhile cooled with ice
2. 2
   workup.ADDITIONwas added
3. 3
   Temperaturewhile cooled with ice
4. 4
   workup.STIRRINGby stirring for another 17 hours
5. 5
   FiltrationThe precipitated solid was filtered off as it
6. 6
   Otherto obtain a solid
7. 7
   workup.STIRRINGby stirring
8. 8
   Washto be washed with 2 L of water three times
9. 9
   Otherwas subsequently dried under reduced pressure
10. 10
    OtherThe resulting dry solid
11. 11
    workup.DISSOLUTIONwas dissolved in 400 mL of trifluoroacetic acid
12. 12
    Filtrationa small amount of insoluble matter was filtered off with a membrane
13. 13
    Filtrationfilter
14. 14
    ConcentrationThe filtrate was concentrated under reduced pressure to about half the amount, which
15. 15
    Washwas then washed with diethyl ether
16. 16
    OtherThe solid was dried under reduced pressure
17. 17
    Washwas washed with water an appropriate number of times
18. 18
    Otherthe resulting solid was dried under reduced pressure

Procedure

198 g of the N-palmitoyloxy-glycyloxysuccinimide synthesized above as a whole was suspended in DMF and, to the resultant solution while cooled with ice with stirring, a suspension of 113 g (0.728 mol) of L-histidine, 55.6 mL (0.400 mol) of triethylamine, and 350 ml of water was added. Subsequently, the resultant solution was stirred for 30 minutes while cooled with ice, and the temperature was then raised to room temperature, followed by stirring for another 17 hours. The precipitated solid was filtered off as it was to obtain a solid. The resultant product was added to a mixed solution of 120 mL of trifluoroacetic acid and 1.5 L of ice water, followed by stirring and then filtering insoluble matter. The resulting solid was placed in a jug to be washed with 2 L of water three times, and was subsequently dried under reduced pressure. The resulting dry solid was dissolved in 400 mL of trifluoroacetic acid, and a small amount of insoluble matter was filtered off with a membrane filter. The filtrate was concentrated under reduced pressure to about half the amount, which was then washed with diethyl ether. The solid was dried under reduced pressure and was washed with water an appropriate number of times, and the resulting solid was dried under reduced pressure to obtain 112 g (54%) of a colorless solid.

Source