Exploring the Potential of Cyclic Peptidyl Antitumor Agents Derived from Natural Macrocyclic Peptide Phakellistatin .

The exploration of novel anticancer compounds based on natural cyclopeptides has emerged as a pivotal paradigm in the contemporary advancement of macrocyclic pharmaceuticals. Phakellistatin is a cycloheptapeptide derived from the brown snubby sponge and exhibits remarkable antitumor activity. In this study, we have designed and synthesized a series of chiral cyclopeptides incorporating the rigid isoindolinone moiety at various sites within the natural cycloheptapeptide Phakellistatin , with the aim of investigating conformationally constrained cyclopeptides as potential antitumor agents.

Photo-induced synthesis, structure and bioactivity of a natural cyclic peptide Yunnanin A analog.

A cyclic analog of natural peptide Yunnanin A was synthesized photoinduced single electron transfer reaction (SET) in the paper. The resulting compound exhibited potent bioactivity (with IC values 29.25 μg mL against HepG-2 cell lines and 65.

Photo-induced synthesis of Axinastatin 3 analogs, the secondary structures and their in vitro antitumor activities.

Cyclic peptides combine several favorable properties such as good binding affinity, target selectivity and low toxicity that make them an attractive modality for drug development. In an effort to identify what conformation could be accounting for the bioactive disparity of natural and synthetic cyclic peptides, some structurally-constrained analogs of cyclopeptide Axinastatin 3 were prepared by photo-induced single electron transfer (SET) reaction. Detailed stereochemistry study was performed by experimental electronic circular dichroism combined with theoretical calculations.