Wild-type phosphotriesterase (PTE) preferentially hydrolyzes the R(P) enantiomers of the nerve agents sarin (GB) and cyclosarin (GF) and their chromophoric analogues. The active site of PTE can be subdivided into three binding pockets that have been denoted as the small, large, and leaving group pockets based on high-resolution crystal structures. The sizes and shapes of these pockets dictate t...

A series of enolic Schiff base aluminum(III) complexes LAlR (where L=NNOO-tetradentate enolic Schiff base ligand) containing ligands that differ in their steric and electronic properties were synthesized. Their single crystals showed that these complexes are five-coordinated around the aluminum center. Their coordination geometries are between square pyramidal and trigonal bipyramidal. Their ca...

Candida antarctica lipase B catalyzed the stereoselective ammoniolysis of N-alkyl aziridine-2-carboxylates in tBuOH saturated with ammonia and yielded the (2S)-aziridine-2-carboxamide and unreacted (2R)-aziridine-2-carboxylate. Varying the N-1 substituent on the aziridine ring changed the rate and stereoselectivity of the reaction. Substrates with a benzyl substituent or a (1'R)-1-phenylethyl s...

A practical dearomative [4 + 3] cycloaddition of furans with vinylcarbenes to access oxa-bridged seven-membered carbocycles, complete and predictable stereoselectivity, is achieved by merging silver catalysis vinyl- N -triftosylhydrazones.

Atropisomeric 3,4-dihydro-2-pyridones undergo stereospecific [2+2]-photocycloaddition in solution with high stereoselectivity (ee > 98% and de > 96%) in the product. The chiral transfer during phototransformation was rationalized based on the stability/reactivity of the biradical.

This study clearly demonstrates that a multi-dentate metal coordination to the leaving group, along with O-5 and/or a protecting group at O-6, has a strong effect on the stereoselectivity of chemical glycosylation.