A convenient synthesis of difficult medium-sized cyclic peptides by Staudinger mediated ring-closure (original) (raw)

A modular synthesis of some biologically relevant cyclic peptides through late stage functionalization.

A modular synthesis of some cyclic peptides related to a class of histone deacetylase inhibitors is reported. The synthesis utilizes a late-stage functionalization of a cyclic tetrapeptide scaffold to link the pendant alkyl chain through cross metathesis. It is observed that while the cross-metathesis reaction of a terminal olefin having a β-substituent is marginally successful with the scaffold, the corresponding reaction with an α,β-unsaturated ketone/ester is more promising. The utility of the protocol is demonstrated through the preparation of three cyclic tetrapeptides structurally related to the novel histone deacetylase inhibitors FR-225497 and trapoxin B.

Cyclic Peptides: Promising Scaffolds for Biopharmaceuticals

Genes, 2018

To date, small molecules and macromolecules, including antibodies, have been the most pursued substances in drug screening and development efforts. Despite numerous favorable features as a drug, these molecules still have limitations and are not complementary in many regards. Recently, peptide-based chemical structures that lie between these two categories in terms of both structural and functional properties have gained increasing attention as potential alternatives. In particular, peptides in a circular form provide a promising scaffold for the development of a novel drug class owing to their adjustable and expandable ability to bind a wide range of target molecules. In this review, we discuss recent progress in methodologies for peptide cyclization and screening and use of bioactive cyclic peptides in various applications.