Brief Summary on Cyclic peptides

We briefly summarize the cyclotides, its types, importance, artificially laboratory synthesis method, and natural sources. Cyclopeptides are peptides in which the terminal amino and carboxyl groups form a peptide bond, thus making compound a cyclic molecule. They are also formed by the intrapeptide linkage between two cystine residues in a peptide chain. These cyclic peptides have several applications in medicine and biology. Cyclic peptides combine several favorable properties such as good binding affinity, target selectivity and low toxicity that make them an attractive modality for the development of therapeutics. We can find several cyclic peptides from natural peptide hormones such as calcitonin, oxytocin, somatostatin, vaso¬pressin, and so on. The synthetic method can provide more versatile cyclic peptide compounds as the repertoire of amino acids and the way of forming cyclic peptides is diverse. Solid-phase peptide synthesis combined with split-and-pool synthesis can prepare fairly large libraries. Cyclopeptides are ubiquitously present in Nature. Their high physiological activity is often a result of the stabilization of certain bio-active conformations upon cyclization while the cyclic structure simultaneously protects against degradation by proteases.