The electrochemical response of S- and R-naproxen enantiomers was investigated on L-cysteine/reduced graphene oxide modified glassy carbon electrode (L-Cys/RGO/GCE). The production of the reduced graphene oxide and L-cysteine on the surface of the glassy carbon electrode was done by using electrochemical processes. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were us...

The factors that govern the substrate reactivity and stereoselectivity of phosphotriesterase (PTE) toward organophosphotriesters containing various combinations of methyl, ethyl, isopropyl, and phenyl substituents at the phosphorus center were determined by systematic alterations in the dimensions of the active site. The wild type PTE prefers the S(P)-enantiomers over the corresponding R(P)-ena...

A series of R and S enantiomers of 2-aminopurine methylenecyclopropane analogues of nucleosides was synthesized. Two diastereoisomeric lipophilic phosphate prodrugs derived from R and S enantiomers of 2,6-diaminopurine analogue were also prepared. Enantioselectivity (diastereoselectivity in case of prodrugs) of in vitro antiviral effects was investigated with human and murine cytomegalovirus (H...

OBJECTIVE To investigate the internal construct validity of the Rivermead Post-Concussion Symptoms Questionnaire (RPQ) by Rasch analysis of data from a national cohort of patients with mild traumatic brain injury. METHODS Data collected at 3 months after mild traumatic brain injury from 2,523 patients were analysed using the partial credit model, describing rating scale structure, local depen...

This investigation describes a new precise, sensitive and accurate stereoselective HPLC method for the simultaneous determination of donepezil enantiomers in tablets and plasma with enough sensitivity to follow its pharmacokinetics in rats up to 12h after single oral dosing. Enantiomeric resolution was achieved on a cellulose tris (3,5-dimethylphenyl carbamate) column known as Chiralcel OD, wit...

We investigated the binding properties of the (R)- and (S)-enantiomers of the muscarinic antagonists trihexyphenidyl, procyclidine, hexahydro-difenidol, p-fluoro-hexahydro-difenidol, hexbutinol, p-fluoro-hexbutinol, and their corresponding methiodides at muscarinic M1, M2, M3 and M4 receptor subtypes. In addition, binding properties of the (R)- and (S)-enantiomers of oxyphencyclimine were studi...

The two enantiomers of 2',3'-dideoxy-3'-thiacytidine (BCH-189) and their 5-fluoro analogs (FTC) were found to be good substrates for human 2'-deoxycytidine kinase with Km values in the 5.7 to 42.1 microM range. The affinity of the (-)-enantiomers was greater than that of the (+)-compounds. These results may explain the greater in vitro antiviral potency against human immunodeficiency virus and ...

This work describes the sequential hydrolysis of bambuterol enantiomers and their monocarbamate metabolites (MONO) catalyzed by human butyrylcholinesterase (BChE) as well as the enzyme inhibition resulting from this process. Particular emphasis is given to the contribution given by MONO to the enzyme inhibition because it was not fully characterized in previous works. Bambuterol and MONO enanti...

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...