Cyanobacterial cyclopeptides : A series of analogues of the cyanobacterial cyclopeptide brunsvicamide A was prepared by effective solid‐support‐based total synthesis. Variations in stereochemistry revealed the importance of the D ‐lysine and the L ‐isoleucine residues for the substrate‐competitive inhibitory activity of brunsvicamide A against carboxypeptidase A.