Supramolecular Catalysis of m-Xylene Isomerization by Cucurbiturils: Transition State Stabilization, Vibrational Coupling, and Dynamic Binding Equilibrium

Cucurbiturils: from synthesis to high-affinity binding and catalysis.

In the wide area of supramolecular chemistry, cucurbit[n]urils (CBn) present themselves as a young family of molecular containers, able to form stable complexes with various guests, including drug molecules, amino acids and peptides, saccharides, dyes, hydrocarbons, perfluorinated hydrocarbons, and even high molecular weight guests such as proteins (e.g., human insulin). Since the discovery of ...

RNA catalysis by a group I ribozyme. Developing a model for transition state stabilization.

Transition state stabilization by a catalytic RNA.

The hairpin ribozyme catalyzes sequence-specific cleavage of RNA through transesterification of the scissile phosphate. Vanadate has previously been used as a transition state mimic of protein enzymes that catalyze the same reaction. Comparison of the 2.2 angstrom resolution structure of a vanadate-hairpin ribozyme complex with structures of precursor and product complexes reveals a rigid activ...

A supramolecular approach to combining enzymatic and transition metal catalysis.

The ability of supramolecular host-guest complexes to catalyse organic reactions collaboratively with an enzyme is an important goal in the research and discovery of synthetic enzyme mimics. Herein we present a variety of catalytic tandem reactions that employ esterases, lipases or alcohol dehydrogenases and gold(I) or ruthenium(II) complexes encapsulated in a Ga(4)L(6) tetrahedral supramolecul...

Catalysis: transition-state molecular recognition?

THE KEY TO UNDERSTANDING THE FUNDAMENTAL PROCESSES OF CATALYSIS IS THE TRANSITION STATE (TS): indeed, catalysis is a transition-state molecular recognition event. Practical objectives, such as the design of TS analogues as potential drugs, or the design of synthetic catalysts (including catalytic antibodies), require prior knowledge of the TS structure to be mimicked. Examples, both old and new...