Synthetic cyclic peptide mimetics

A cyclic peptide mimetic having the structure c (X1-X2-X3-X4-X5-X6) wherein:

• each of X1, X2, X3, X4, X5, and X6 is either an L-amino acid residue, a D-amino acid residue, or X7;
• and wherein one of X1, X2, X3, X4, X5, and X6 is defined as X7;
• and
• wherein the remaining X1, X2, X3, X4, X5, and X6 which are not defined as X7 are amino acid residues in alternating L-configuration and D-configuration;
• wherein X7 is an aza-amino acid residue or azasulfuryl-amino acid residue having the structure:
• wherein the R group is the same R group as defined in naturally occurring and synthetic amino acids;
• R1 is hydrogen, alkyl, aryl, heteroalkyl, heteroaryl, aryl alkyl or heteroaryl alkyl, or R1 and R could together form a cyclic ring;
• Z is a carbonyl group of an adjacent amino acid residue;
• X is an amine group of an adjacent amino acid residue;
• and wherein each of X1, X2, X3, X4, X5, and X6 is either unsubstituted or substituted by a conjugate moiety.