Reflecting recent work in the

Ring-closing metathesis, RCM, is an attractive reaction for the preparation of artificially designed peptides. Until now, RCM has been used for fully or partially protected peptides.

Researchers in the Yoshiya Lab, published in Organic & Biomolecular Chemistry, evaluated different RCM conditions of an unprotected peptide in water. They confirmed that the addition of MgCl₂ and/or use of acidic conditions enables the efficient RCM reaction of unprotected model peptides and the octreotide analogues in water.

As can be seen from the fact that native chemical ligation in water flourishes for the preparation of peptides/proteins, the combination of unprotected peptides and water should be superior to the combination of protected peptides/proteins and organic solvents from the viewpoint of solubility and applicability.

The proposed method in this work is the first non-disulphide type connection reaction between homo functionalities in water, which could become a cornerstone of artificial bioactive peptide mimetic development in future.