反应详情

The title compound was prepared by starting with 200 mg of Ac-Tyr(Bzl)-Val-Ala-N(C6H13)2 which was reduced with hydrogen under high pressure with 20% Pd/C catalyst in methanol. The catalyst was filtered. The solution was concentrated under reduced pressure, dissolved, and lyophilized (15B mg). The peptide was phosphotitylated with 1H-tetrazole (79.0 mg, 4.0 eq.) and di-t-butyl diethylphosphoramidite (312 mL, 4.0 eq.) in DCM (50 mL) while stirring at room temperature for 1 hour. The compound was then treated with 2.0 mL 70% aqueous t-butyl-hydroperoxide to the solution for 1 hour. The solution was then concentrated under reduced pressure. The peptide was deprotected with 95% TFA/5% water (20 mL) while stirring for 1 hour. The solution was then concentrated under reduced pressure and purified by preparative RP-HPLC using a gradient of 20% to 50% B over 120 minutes. The appropriate fractions were combined and lyophilized yielding Ac-Tyr(PO3H2)-Val-Ala-N(C6H13)2 (11.0 mg, MS=639.3, Calculated=640.43).

1. filtrationThe catalyst was filtered
2. concentrationThe solution was concentrated under reduced pressure
3. dissolutiondissolved
4. concentrationThe solution was then concentrated under reduced pressure
5. stirringwhile stirring for 1 hour
6. concentrationThe solution was then concentrated under reduced pressure
7. custompurified by preparative RP-HPLC
8. customover 120 minutes