Реакция #95986

Уравнение реакции

agmatine-dichlorohydrate

dimethylformamide

triethylamine

→

L-prolyl-agmatine-dichlorohydrate

Растворители

pyridine

Условия реакции

Обработка

1. 1
   workup.ADDITIONadded
2. 2
   ДругоеThe reaction mixture is evaporated at reduced pressure
3. 3
   workup.DISSOLUTIONThe residue is dissolved in a mixture of 50 ml of 0.1 N hydrochloric acid and 20 ml of ethyl acetate
4. 4
   Экстракцияthe aqueous layer is extracted twice with 20 ml of diethyl ether
5. 5
   Экстракцияextracted five times with 20 ml of chloroform
6. 6
   ПромывкаThe combined chloroform layers are washed twice with water
7. 7
   Другоеevaporated at reduced pressure
8. 8
   workup.DISSOLUTIONThe evaporation residue, benzyloxycarbonyl-L-prolyl-agmatine-hydrochloride (RF3 0.32 to 0.42), is dissolved in 40 ml of methanol
9. 9
   workup.ADDITION10 ml of 1 N hydrochloric acid added
10. 10
    Фильтрацияthe catalyst is filtered
11. 11
    Промывкаwashed with water
12. 12
    Другоеthe filtrate evaporated at reduced pressure
13. 13
    Фильтрацияfiltered
14. 14
    Промывкаwashed with diethyl ether
15. 15
    Сушкаdried over potassium hydroxide at reduced pressure
16. 16
    Другое[α]D20 =-33.25° (c=1, methanol)

Методика

3.7 g (10 mmoles) of benzyloxycarbonyl-L-prolyl-p-nitrophenyl ester (Goodman and Stueben: J. Am. Chem. Soc., 81, 3980, 1959) are dissolved in a mixture of 10 ml of dimethylformamide and 5 ml of pyridine, 2.03 g (10 mmoles) of agmatine-dichlorohydrate (in formula II A represents an H2N--C(NH)-- residue, B a chlorine atom and n=2) and 1.4 ml (10 mmoles) of triethylamine added, and stirred for 16 to 20 hours. The reaction mixture is evaporated at reduced pressure. The residue is dissolved in a mixture of 50 ml of 0.1 N hydrochloric acid and 20 ml of ethyl acetate, the aqueous layer is extracted twice with 20 ml of diethyl ether, neutralized with solid sodium hydrogen carbonate and then extracted five times with 20 ml of chloroform. The combined chloroform layers are washed twice with water and evaporated at reduced pressure. The evaporation residue, benzyloxycarbonyl-L-prolyl-agmatine-hydrochloride (RF3 0.32 to 0.42), is dissolved in 40 ml of methanol, 10 ml of 1 N hydrochloric acid added, and the mixture hydrogenated in the presence of palladium charcoal. When the reaction is concluded, the catalyst is filtered, washed with water, and the filtrate evaporated at reduced pressure. The evaporation residue is worked up with diethyl ether, filtered, washed with diethyl ether and dried over potassium hydroxide at reduced pressure. Yield: 2.1 g (70 percent) of the named compound. M.p.: 186° to 189° C.; RF4 0.15 to 0.25; [α]D20 =-33.25° (c=1, methanol).

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