The first pre-steady-state kinetic analysis of the stereoselectivity of a DNA polymerase, Pol beta from rat brain, toward Rp and Sp isomers of dATPalphaS, and alteration of the stereoselectivity by various metal ions and by site-directed mutagenesis are reported. Diastereomers of dATPalphaS were synthesized by enzymatic methods to >98% purity. The rate of polymerization (k(pol)) and the apparen...

A domino reaction catalyzed by palladium gives access to tetrahydrofluorenone scaffolds with full regio- and stereoselectivity in a single step, where the precursor dienes originate from naturally occurring benzoic acid.

The involvement of cytochrome P-450 (CYP) 2D isoforms in the metabolism of mianserin and the stereoselectivity of their catalytic activities were investigated by using five CYP2D isoforms (CYP2D1, 2D2, 2D3, 2D4, and 2D6). Using RS-mianserin as a substrate, we found that five CYP2D isoforms had similar levels of 8-hydroxylation activity. However, N-demethylation activity differed among the isofo...

The stereoselectivity of the reaction between (R)-(-)-2-butylamine and the diastereomeric proton-bound complexes of (+)-catharanthine (C) or (-)-vindoline (V) with some chiral amido[4]resorcinarenes has been investigated in the gas phase by ESI-FT-ICR-MS. The reaction stereoselectivity (0.56 < k(homo)/k(hetero) < 16.9) is found to depend critically on the functional groups present in the chiral...

The stereoselective pharmacokinetics of BOF-4272 enantiomers in rats and dogs was investigated by simultaneously measuring concentrations in arterial, portal, and venous plasma, the liver, and the kidney at 2 h after the oral administration of the racemic drug. The concentrations of BOF-4272 enantiomers were measured using high-performance liquid chromatography. The concentrations of the S(-) e...

Inositol dehydrogenase (EC 1.1.1.18) from Bacillus subtilis is shown to have a nonpolar cavity adjacent to the active site, allowing racemic protected inositol derivatives such as 4-O-benzyl-myo-inositol to be recognized with very high apparent stereoselectivity.

Using iterative lithiation-borylation homologations, the mycolactone toxin core has been synthesized in 13 steps and 17% overall yield. The rapid build-up of molecular complexity, high convergence and high stereoselectivity are noteworthy features of this synthesis.

[reaction: see text] Free radicals generated by the decarboxylation of dimethoxydioxanecarboxylic acids derived from L-(+)-tartaric acid and L-glyceric acid added to some maleimides and acrylates with high stereoselectivity. This method provides easy access to some chiral building blocks.

Trifluoromethylated pyrrolidines have been synthesized via catalytic asymmetric 1,3-dipolar cycloaddition with excellent stereoselectivity for the first time. Epimerization of the endo-pyrrolidines obtained from cis-4,4,4-trifluorocrotonate into the exo-pyrrolidines was also revealed.

An efficient iron(II)-catalyzed alkoxycarbonylation reaction between N-vinylacetamides and carbazates is reported. The corresponding useful highly substituted (β-acylamino)acrylates could be obtained in reasonable to good yields and stereoselectivity under mild reaction conditions.