The first two highly enantioselective palladium-catalyzed allylic alkylations with benzylic nucleophiles activated with Cr(CO)3 have been developed. These methods enable the enantioselective synthesis of “α-2-propenyl benzyl” motifs, which are important scaffolds in natural products and pharmaceuticals. A variety of cyclic and acyclic allylic carbonates are competent electrophilic partners furnishing the products in excellent enantioselectivity (up to 99% ee and 92% yield). This approach was employed to prepare a nonsteroidal anti-inflammatory drug analogue.

The first cobalt-catalyzed enantioselective Negishi cross-coupling reaction, and the first arylation of α-halo esters with arylzinc halides, are disclosed. Employing a cobalt-bisoxazoline catalyst, various α-arylalkanoic esters were synthesized in excellent enantioselectivities and yields (up to 97 % ee and 98 % yield). A diverse range of functional groups, including ether, halide, thioether, silyl, amine, ester, acetal, amide, olefin and heteroaromatics is tolerated by this method. This method was suitable for gram-scale reactions, enabling the synthesis of (R)-xanthorrhizol with high enantiopurity. Radical clock experiments support the intermediacy of radicals.

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A simple, specific, and precise liquid chromatographic-electrospray ionization mass spectrometric (LC-ESI-MS) method has been developed for determination of nimodipine concentration in human plasma. The method involves the addition of 200 microL of saturated sodium bicarbonate (NaHCO(3)) solution to plasma to improve the extraction recovery, liquid-liquid extraction of nimodipine from plasma samples with anhydrous diethyl ether, simple reversed-phase chromatography, and ESI mass spectrometric detection in negative ion selected ion monitoring mode (SIM) using target [M-] ions at m/z 417 and m/z 359 for nimodipine and nitrendipine (internal standard, IS), respectively. A complete analytical run was achieved within 3.5 min. The limit of quantification was 0.5 ng/mL. The method was validated within a linear range of 0.5-100 ng/mL. The correlation coefficient for the calibration regression line was 0.9995 or better. Intra- and inter-batch accuracy and precision were acceptable. Analyte was stable in a battery of stability studies. The method has been successfully used in a bioequivalence study.