| Popis: |
To achieve the desired biological activity of synthetically produced peptides, several properties are important, such as peptide hydrophobicity, net charge, amphipathic nature, and secondary structure. [1] The secondary structure of ferrocene-derived peptidomimetics can be tuned by the number and type of constitutive amino acids, modification of their chirality, and bulkiness of C- and N-protecting groups, starting from the choice of ferrocene backbone: ferrocene amino acid (Fca) or symmetrically disubstituted ferrocene diacid (−OC−Fn−CO−) and diamine (−NH−Fn−NH−). Our study of ferrocene diamine derived peptides started with Y-Ala-NH-Fn-NH-Ala-Y (Ia, Y=Ac, Boc) and was extended by the preparation of their homologues Ac-AA-NH-Fn-NH-AA- Boc (Ib, AA=Val, Leu, Phe). [2-5] To find out how the side chain of amino acids affects the pattern of hydrogen bonding, we decided to replace an Ala residue with hydrophobic L- and D-amino acids (Leu, Val and Phe) to generate peptidomimetics II (Fig. 1). To investigate whether the dipeptides II adopt ordered conformations supported by IHBs in solution, we performed IR, NMR and CD spectroscopic studies. |
