反応 #531775

反応方程式

dicyclohexylamine

Nα -t-butyloxycarbonyl-O-benzyl-L-tyrosyl-D-alanyl-glycine

DCC

L-phenylalanine, methyl ester

→

title compound

収率 82.0%

Nα -t-Butyloxycarbonyl-O-benzyl-L-tyrosyl-D-alanyl-glycyl-L-phenylalanine, methyl ester

収率 82.0%

溶媒

DMF

反応条件

後処理

1. 1
   workup.STIRRINGThe mixture was stirred for 5 minutes at 0° C.
2. 2
   workup.STIRRINGStirring
3. 3
   workup.WAITat room temperature for 48 hours
4. 4
   温度The reaction mixture was cooled to 0° C.
5. 5
   その他the resulting precipitate was collected
6. 6
   濃縮The filtrate was concentrated in vacuo
7. 7
   workup.DISSOLUTIONThe residue was dissolved in ethyl acetate
8. 8
   抽出the ethyl acetate solution was extracted successively with 1 N sodium bicarbonate, water, 0.75 N citric acid, and water
9. 9
   乾燥The ethyl acetate solution was dried over magnesium sulfate
10. 10
    濃縮concentrated in vacuo
11. 11
    その他The resulting oil was crystallized from ether
12. 12
    その他recrystallized from ethyl acetate

実験手順

To 30 ml. of DMF were added 2.5 gms. (0.005 moles) of Nα -t-butyloxycarbonyl-O-benzyl-L-tyrosyl-D-alanyl-glycine (prepared as in Example 1) and 1.08 gms. (0.005 moles) of the hydrochloride salt of L-phenylalanine, methyl ester. The mixture was stirred at 0° C., and 0.99 ml. (0.005 moles) of dicyclohexylamine was added. The mixture was stirred for 5 minutes at 0° C., and 670 mg. (0.005 mmoles) of HBT and 1.03 gms. (0.005 moles) of DCC were added. Stirring was continued at 0° C. for 2 hours and then at room temperature for 48 hours. The reaction mixture was cooled to 0° C., and the resulting precipitate was collected. The filtrate was concentrated in vacuo. The residue was dissolved in ethyl acetate, and the ethyl acetate solution was extracted successively with 1 N sodium bicarbonate, water, 0.75 N citric acid, and water. The ethyl acetate solution was dried over magnesium sulfate and concentrated in vacuo. The resulting oil was crystallized from ether and recrystallized from ethyl acetate to give 2.7 grams (82%) of the title compound, m.p. 149°-152° C. [α]D25 +22° (C=0.5, MeOH).

出典