تفاعل #323684

معادلة التفاعل

dibenzyl N-(N-tert-butoxycarbonyl-L-valyl)-L-glutamate

anisole

docosanoyl chloride

docosanoic acid

thionyl chloride

→

dibenzyl N-(N-docosanoyl-L-valyl)-L-glutamate

المردود 47.3%

المذيبات

triethylamine

trifluoroacetic acid

tetrahydrofuran

benzene

benzene

tetrahydrofuran

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةwas refluxed for 1 hour
2. 2
   أخرىAfter removal of the solvent under reduced pressure
3. 3
   أخرىbenzene was evaporated off
4. 4
   أخرىto give crude docosanoyl chloride
5. 5
   أخرىEvaporation of trifluoroacetic acid under reduced pressure
6. 6
   أخرىgave a residue which
7. 7
   workup.DISTILLATIONBenzene was distilled off
8. 8
   أخرىto leave crude dibenzyl N-(L-valyl)-L-glutamate, which
9. 9
   أخرىthe solvent was removed under reduced pressure
10. 10
    workup.DISSOLUTIONthe residue was dissolved in chloroform
11. 11
    غسيلThe chloroform solution was washed with 1N sodium hydroxide solution, 1N hydrochloric acid solution
12. 12
    تجفيفan aqueous solution of sodium bicarbonate successively, and then dried over magnesium sulfate
13. 13
    أخرىAfter evaporation of the solvent
14. 14
    أخرىthe residue was purified
15. 15
    غسيلElution with chloroform

الإجراء التجريبي

A mixture of docosanoic acid (500 mg) and thionyl chloride (2 ml) in benzene (5 ml) was refluxed for 1 hour. After removal of the solvent under reduced pressure, the residue was taken up in benzene and benzene was evaporated off. This operation was repeated three times to give crude docosanoyl chloride. Meanwhile, a solution of dibenzyl N-(N-tert-butoxycarbonyl-L-valyl)-L-glutamate (773 mg) and anisole (0.25 ml) in trifluoroacetic acid (1 ml) was stirred at 0° C. for 1 hour. Evaporation of trifluoroacetic acid under reduced pressure gave a residue which was taken up in benzene. Benzene was distilled off by using a high vacuum pump. This operation was repeated three times to leave crude dibenzyl N-(L-valyl)-L-glutamate, which was dissolved in tetrahydrofuran (5 ml). To this solution were added triethylamine (0.7 ml) and a solution of docosanoyl chloride prepared as mentioned above in tetrahydrofuran (3 ml). After the resulting mixture was stirred at room temperature for 3 hours, the solvent was removed under reduced pressure, and the residue was dissolved in chloroform. The chloroform solution was washed with 1N sodium hydroxide solution, 1N hydrochloric acid solution, and an aqueous solution of sodium bicarbonate successively, and then dried over magnesium sulfate. After evaporation of the solvent, the residue was purified by being subjected to a silica gel column chromatography. Elution with chloroform and an usual work-up afforded dibenzyl N-(N-docosanoyl-L-valyl)-L-glutamate (520 mg, powder).

المصدر