Table 2. Comparison of the Yield and Racemization of Z-Gly-Phe-Val-OMe Synthesized Using Various Coupling Reagents.
entry | coupling reagent | yield (%) | racemization (%) |
---|---|---|---|
1 | HDMB | 90 | 2.9 |
2 | HDMA | 90 | 0.7 |
3 | HBTU | 89 | 5.9 |
4 | HATU | 90 | 1.6 |
5 | TCBOXY | 90 | n.d.a |
No racemization could be detected.