Solid-phase synthesis and bioactivity evaluation of cherimolacyclopeptide E

Recent Advances in Macrocyclic Drugs and Microwave-Assisted and/or Solid-Supported Synthesis of Macrocycles

Macrocycles represent attractive candidates in organic synthesis and drug discovery. Since 2014, nineteen macrocyclic drugs, including three radiopharmaceuticals, have been approved by FDA for the treatment of bacterial and viral infections, cancer, obesity, immunosuppression, etc. As such, new synthetic methodologies and high throughput chemistry (e.g., microwave-assisted and/or solid-phase synthesis) to access various macrocycle entities have attracted great interest in this chemical space. This article serves as an update on our previous review related to macrocyclic drugs and new synthetic strategies toward macrocycles (Molecules, 2013, 18, 6230). In this work, I first reviewed recent FDA-approved macrocyclic drugs since 2014, followed by new advances in macrocycle synthesis using high throughput chemistry, including microwave-assisted and/or solid-supported macrocyclization strategies. Examples and highlights of macrocyclization include macrolactonization and macrolactamization, transition-metal catalyzed olefin ring-closure metathesis, intramolecular C-C and C-heteroatom cross-coupling, copper- or ruthenium-catalyzed azide-alkyne cycloaddition, intramolecular SNAr or SN2 nucleophilic substitution, condensation reaction, and multi-component reaction-mediated macrocyclization, and covering the literature since 2010.

Natural Bridged Bicyclic Peptide Macrobiomolecules from Celosia argentea and Amanita phalloides

Bridged peptide macrobicycles (BPMs) from natural resources belong to types of compounds that are not investigated fully in terms of their formation, pharmacological potential and stereo-chemical properties. This division of biologically active congeners with multiple circular rings, has merits over other varieties of peptide molecules. BPMs form one of the most hopeful grounds for establishment of drugs because of their close resemblance and biocompatibility to proteins, and these bio-actives are debated as feasible realistic tools in diverse biomedical applications. Despite huge potential, poor metabolic stability and cell permeability limit the therapeutic success of macrocyclic peptides. In this review, we have comprehensively explored major bicyclic peptides sourced from plants and mushrooms including βs-leucyl-tryptophano-histidine bridged and tryptophano-cysteine bridged peptide macrobicycles. The unique structural features, structure activity relationship, synthetic routes, bioproperties and therapeutic potential of the natural BPMs are also discussed.