Efrapeptins are peptaibiotics produced by the fungus Tolypocladium niveum, a soil hyphomycete, as a microheterogenic mixture. They are Aib-rich compounds with several L-Pip and Iva residues, containing an unusual cationic head group derived from leucinol at the C-terminus and an acetylated N terminus. Interestingly, they display a wide range of biological and medicinal properties. However, the synthesis of efrapeptins is largely hampered by the incomplete peptide coupling reactions of sterically hindered α,α‑dialkyl amino acids (Aib). Using a combination of solid and solution phase techniques with a fragment condensation strategy, we were able to describe the total synthesis of efrapeptin C, and several other analogues of the series. Moreover we are interested to investigate the conformational aspect of these peptides by circular dichroism measurements to distinguish between 310 and α‑helical structures and also to determine the actual criteria responsible for these biological activities. Apart from this, the inhibitory activities of these compounds towards F1‑ATPase from E. coli provides more insight into the biological activities of these molecules.
Thus our current research project on efrapeptin series enables the synthesis of similar peptaibols, incorporating Aib and Iva residues, which may lead to the synthesis of naturally occurring peptides with interesting new properties.
Here you will find personal data and further information about the members of the workgroup Organic Chemistry III.
|Mrs. Iris Dopheide|
|Phone:||0521 106 6963|
|Fax:||0521 106 8094|