Reaktion #72431

Reaktionsgleichung

HOBt

triethylamine

H2O

WSC.HCl

Z-Glu-OBzl

H-Nle-OBzl.HCl

→

Z-Glu(Nle-OBzl)-OBzl

Lösungsmittel

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe resulting reaction solution
2. 2
   TemperaturThe temperature of the reaction solution was gradually raised
3. 3
   EinengenThen, the reaction mixture was concentrated under reduced pressure, ethyl acetate (100 mL)
4. 4
   workup.ADDITIONwas added to the resulting residue
5. 5
   Waschenthe organic phase was then washed once with water (30 mL), twice with a 5% aqueous solution of citric acid (30 mL), once with a saturated common salt solution (30 mL), twice with a 5% aqueous solution of sodium hydrogen carbonate (30 mL) and once with a saturated common salt solution (30 mL)
6. 6
   TrocknenThen, the organic phase was dried over anhydrous magnesium sulfate
7. 7
   SonstigeThe magnesium sulfate was removed through filtration
8. 8
   Einengenthe filtrate was concentrated under reduced pressure
9. 9
   SonstigeThe resulting residue was recrystallized from ethyl acetate and n-hexane
10. 10
    Sonstigethe crystals thus obtained
11. 11
    Filtrationwere collected through filtration
12. 12
    Sonstigedried under reduced pressure

Vorschrift

The resulting H-Nle-OBzl.HCl was dissolved in methylene chloride (30 mL) and the resulting reaction solution was maintained at 0° C. To the reaction solution, Z-Glu-OBzl (N-α-carbobenzoxy-L-glutamic acid α-benzyl ester, 0.70 g, 1.90 mM), triethylamine (0.29 mL, 1.1 eq., 2.10 mM), HOBt.H2O (1-hydroxybenzotriazole hydrate, 0.32 g, 1.1 eq., 2.10 mM), and WSC.HCl (0.41 g, 1.1 eq., 2.10 mM) was added. The temperature of the reaction solution was gradually raised and stirred at room temperature overnight (16 hours). Then, the reaction mixture was concentrated under reduced pressure, ethyl acetate (100 mL) was added to the resulting residue, and the organic phase was then washed once with water (30 mL), twice with a 5% aqueous solution of citric acid (30 mL), once with a saturated common salt solution (30 mL), twice with a 5% aqueous solution of sodium hydrogen carbonate (30 mL) and once with a saturated common salt solution (30 mL). Then, the organic phase was dried over anhydrous magnesium sulfate. The magnesium sulfate was removed through filtration and the filtrate was concentrated under reduced pressure. The resulting residue was recrystallized from ethyl acetate and n-hexane, the crystals thus obtained were collected through filtration and dried under reduced pressure to give crystals of Z-Glu(Nle-OBzl)-OBzl (0.91 g).

Quelle