Table 1.
Yields obtained with different cyclization conditions.
| Peptide length b | Cyclization conditions | Cyclization reagent | Cyclization yield % |
|---|---|---|---|
| 3-mer c | aq. Cs2CO3/DMFa | BrAc-OSu | 25 |
| TBS-2X | BrAc-OSu | Not observed | |
|
| |||
| aq. NaHCO3 0.1 M | BrAc-OSu | 56 | |
| BrAc-DNP | n.d. | ||
| ClAc-OH | 46 | ||
| BrAc-OH | 50 | ||
| MalC3 | n.d. | ||
| MalC4 | n.d. | ||
|
| |||
| 6-mer c | aq. NaHCO3 0.1 M | BrAc-OSu | 50 |
| BrAc-DNP | 24 | ||
| ClAc-OH | n.d. | ||
| BrAc-OH | n.d. | ||
| MalC3 | 20 | ||
| MalC4 | 35 | ||
|
| |||
| 10-mer c | aq. NaHCO3 0.1 M | BrAc-OSu | 44 |
| BrAc-DNP | 33 | ||
| ClAc-OH | n.d. | ||
| BrAc-OH | n.d. | ||
| MalC3 | 17 | ||
| MalC4 | 22 | ||
a
5% Cs2CO3/H2O/DMF (w/v/v)
b
Spotted sequences: Z-[AA]n-HMPA-BCB-PUC, with Z = cyclization reagent.
c
3-mer: WKL; 6-mer: GLSWKL; 10-mer: GALSGLSWKL. n.d. = not determined.