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Results demonstrate the preparation of 1-azabicyclic ketones derived from quinidine and quinine. The ketones are single isomer 1,2-amino alcohols with three stereogenic centers. Data suggest that the compounds are of low molecular weight, exhibit bicyclic structures and are useful in nucleophilic addition of carbonyl groups.

Quinidine was employed as an open channel probe in the examination of the kinetic state of 4-aminopyridine blocked channels. Quinidine, in the presence of 0.2-1 mM of 4-aminopyridine, was found to stem charge return and promote partial charge immobilization. Results suggest that the 4-aminopyridine resident in the channel provided an allosteric modulation of the quinidine binding site.

Research using epicardial activation sequence mapping techniques in perfused rabbit heart shows that temperature can be used to modulate drug-induced arrhythmic responses to quinidine. Experiments using the Langendorff-perfused hearts of New Zealand White rabbits to determine myocardial activation and recovery trends in the presence of quinidine are described.

Analysis of the influence of cinchona alkaloids quinidine and quinine on voltage-gated membrane conductances in excitable tissues using the whole-cell patch clamp method reveals that the alkaloids inhibit many of the voltage-activated currents and trigger a large outward current in the presence of depolarized potentials in the cell. The outward current has a reversal potential of 0 mV, with the extracellular treatment of acetate, cobalt and halothane inhibiting the current. The effects of the alkaloids indicate that opening of hemi-gap junctional channels are the sources of nonselective conductance.

The first catalytic, enantioselective syntheses of quinine and quinidine is described. Asymmetric catalyst-based synthesis opens the possibility of accessing diastereomeric products with the help of a common route.

The effect of chromatographic conditions on the performance of chiral monolithic poly(O-[2-(methacryloyloxy)ethylcarbamoyl]-10, 11-dihydroquinidine-co-ethylene dimethacrylate-co-2-hydroxyethyl methacrylate) columns in the capillary electrochromatography of enantiomers has been studied. The flow velocity was found to be proportional to the pore size of the monolith and both the pH and the composition of the mobile phase. The length of both open and monolithic segments of the capillary column was found to exert a substantial effect on the run times. The use of monoliths as short as 8.5 cm and the 'short-end' injection technique enabled the separations to be achieved in ~5 min despite the high retentitivity of the quinidine selector. Very high column efficiencies of close to 250 000 plates/m and good selectivities were achieved for the separations of numerous enantiomers using the chiral monolithic capillaries with the optimized chromatographic conditions.

Monolithic columns for chiral capillary electrochromatography have been prepared within the confines of untreated fused-silica capillaries in a single step by a simple copolymerization of mixtures of O-[2-(methacryloyloxy)ethylcarbamoyl]-10, 11-dihydroquinidine, ethylene dimethacrylate, and glycidyl methacrylate or 2-hydroxyethyl methacrylate in the presence of mixture of cyclohexanol and 1-dodecanol as a porogenic solvent. The porous properties of the monolithic columns can easily be controlled through changes in the composition of the binary porogenic solvent. Although both thermal- and IN light-initiated polymerizations afford useful capillary columns, monoliths prepared using the former approach exhibit better chromatographic properties. The ability to control pore size independently of the polymerization mixture composition enables the preparation of monoliths with varying percentages of the chiral monomer and cross-linker, as well as the optimization of their separation properties. Very good separations of model racemate (R,S)-N-3,5-dinitrobenzoylleucine were achieved using an optimized monolithic CEC column, with high efficiencies of up to 74 000 plates/m for the retained peaks.

X-ray and kinetic studies probe into the origin of high enantioselectivity in the Sharpless asymmetric dihydroxylation of chiral olefins. Notwithstanding contrary evidence from the crystal structure of an OsO4-ligand complex, kinetic experiments strongly suggest a mechanism in which the stereofacial attack proceeds through a mu-oxo-bridged bisosmium(VIII) species where the dihydroquinine ether ligand is bonded to the hexacoordinate Os via the bridgehead nitrogen of its bicycloazaoctane arms.