Natural Bioactive Cyclic Peptides and Peptidomimetics

Abstract

Abstract Cyclic peptides isolated from natural resources show a vast range of biological profiles. Because of their special structural or conformational nature and ability to accommodate various amino acids, they are good drug candidates and tools to use to study biochemical interactions. The biological competency of these molecules covers a variety of medical illnesses such as cancer and bacterial, fungal, and viral diseases. Compared to other naturally occurring bioactive ingredients, the cyclic peptide class exhibits significant biological activities. This characteristic has inspired scientists and researchers to modify naturally occurring derivatives in order to produce better drug candidates for specific purposes. The advantage of cyclic peptides over their linear counterparts is the special structural features that provide a large surface area for interacting with the target, making them better drug candidates. Among the naturally occurring cyclic peptides, a few are in clinical phase trials (namely, cyclosporin A, gramicidin S, tyrocidine, and plitidepsin). This chapter covers the isolated cyclic peptides and peptidomimetics that have been discovered in the last two decades, along with their biological profiles and structural features that could be of interest to biologists and chemists.