Cyclic pentapeptides having a beta-turn and a gamma-turn.

摘要

Cyclic pentapeptides having a gamma -turn and a beta -turn wherein the cyclic pentapeptide has the following formula (I): Cyclo(-A1-A2-A3-A4-A5-) (I> wherein A1, A2, A3, A4 and A5 are amino acid residues; said pentapeptide comprising amino acid residues in positions 1-2-3 to form a gamma -turn, and amino acid residues in positions 3-4-5-1 to form a beta -turn in combination with the gamma -turn; in which D- alpha -amino acid residues are selected for A1, A3 and A5 and L- alpha -amino acid residues are selected for A2 and A4 or wherein L- alpha -amino acid residues are selected for A1, A3 and A5 and D- alpha -amino acid residues are selected for A2 and A4; are provided. Compounds having gamma -turns and beta -turns can be systhesized, regardless of the kinds of amino acid residues, and it is possible to synthesize compounds in which desired amino acid residues are introduced into sites of beta -turn and gamma -turn based on their importance from the viewpoint of biological activity. The present invention is therefore available for design of compounds having biological activity.