Azotides as Modular Peptide-Based Ligands for Asymmetric Lewis Acid Catalysis

Designer peptides as versatile building blocks for functional materials

Peptides and pseudopeptides show distinct self-assembled nanostructures such as fibers, nanotubes, vesicles, micelles, toroids, helices and rods. The formation of such molecular communities through the collective behavior of molecules is not fully understood at a molecular level. All these self-assembled nanostructured materials have a wide range of applications such as drug delivery, gene delivery, biosensing, bioimaging, catalysis, tissue engineering, nano-electronics and sensing. Self-assembly is one of the most efficient and a simple strategy to generate complex functional materials. Owing to its significance, the last few decades witnessed a remarkable advancement in the field of self-assembling peptides with a plethora of new designer synthetic systems being discovered. These systems range from amphiphilic, cyclic, linear and polymeric peptides. This article presents only selected examples of such self-assembling peptides and pseudopeptides.

Site-Selective Nitrene Transfer to Conjugated Olefins Directed by Oxazoline Peptide Ligands

Site-selective nitrene transfer to di- and polyene substrates has been achieved using designed peptide-embedded bioxazoline ligands capable of binding copper. In model 1,3-diene substrates, the olefinic position proximal to a directing group was selectively functionalized. Additional studies indicate that this selectivity stems from non-covalent substrate-catalyst interactions. The peptide-mediated nitrene transfer was also applied to polyene natural product retinol and selective proximal functionalization allowed access to a cis-pyrroline modified retinoid.