Prolyl oligopeptidase B from Galerina marginata (GmPOPB) has recently been discovered as a peptidase capable of breaking and forming peptide bonds to yield a cyclic peptide. Despite the relevance of prolyl oligopeptidases in human biology and disease, a kinetic analysis pinpointing rate-limiting steps for a member of this enzyme family is not available. Macrocyclase enzymes are currently exploi...

This paper describes the synthesis of four aryl amide-based macrocycles through the 1 + 1 formation of two 1,2,3-triazole units by click chemistry. Two series of aryl amide-based precursors that bear two azide or acetylene units have been prepared. Intramolecular hydrogen bonding has been utilized to induce them to adopt a U-styled conformation, which remarkably promotes the macrocyclization of...

Cyclodepsipeptide natural products often display intriguing biological activities that along with their complex molecular scaffolds, makes them interesting targets for chemical synthesis. Although cyclodepsipeptides feature highly diverse chemical structures, their synthesis is often associated with similar synthetic challenges such as the establishment of a suitable macrocyclization methodolog...

The first metalated porphyrazinediols 11 have been prepared from (L)-(+)-dimethyl tartrate via conversion into the corresponding dispoke or 2,3-dimethoxy-2,3-butanediyl protected 2,3-dihydroxymaleonitrile, Linstead macrocyclization, transmetalation, and deprotection. Their stability is very dependent on the nature of the metal ion in the cavity of the porphyrazine. Reaction of these porphyrazin...

Macrocyclic peptides have emerged as attractive molecular scaffolds for the development of chemical probes and therapeutics. In this synopsis, we highlight contemporary strategies to access peptide macrocycles from ribosomally produced polypeptides. Challenges that have been tackled in this area involve orchestrating the desired macrocyclization process in the presence of unprotected polypeptid...

A catalysis-based approach to the core region 24 of the antitumor agents salicylihalamides A and B is reported. Key steps are two asymmetric hydrogenations of beta-keto esters 13 and 16 catalyzed by [(R)-BINAP.RuCl(2)](2).NEt(3) and an RCM-based macrocyclization effected by the NHC-containing ruthenium carbene 21. The stereochemical outcome of the latter reaction is controlled by remote substit...