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Carbonyl Reduction (carbonyl + reduction)
Selected AbstractsAsymmetric Carbonyl Reduction with Borane Catalyzed by Chiral Phosphinamides Derived from L-Amino Acid.CHEMINFORM, Issue 19 2003Kangying Li Abstract For Abstract see ChemInform Abstract in Full Text. [source] Asymmetric Carbonyl Reductions with Microbial KetoreductasesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2008Menno Abstract The biocatalytic reduction of ,-keto esters and some aromatic ketones in the presence of a variety of ketoreductases from different microbial origins was investigated. The prochiral selectivity was generally high and both product enantiomers could be obtained by a proper choice of enzyme. Aromatic ketones reacted slower than the esters but the prochiral selectivity was often high. The organic cosolvent tolerance of these enzymes was rather variable but useful activity could be maintained in a number of cases. Reduction of the oxidized cofactors NAD and NADP, employing 2-propanol as a sacrificial reductant, was catalyzed by the ketoreductases from Rhodococcus erythropolis and Lactobacillus kefir, respectively. [source] Reduction of the Potential Anticancer Drug Oracin in the Rat Liver In-vitroJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 5 2000BARBORA SZOTÁKOVÁ Studies on the metabolism of the potential cytostatic drug oracin have shown that a principal metabolite of oracin is 11-dihydrooracin (DHO). We conducted in-vitro experiments to investigate the extent of oracin carbonyl reduction in microsomal or cytosolic fractions and to find out the enzymes involved under these conditions. Among several inducers of rat cytochrome P450 only 3-methylcholanthrene caused a significant (P < 0.01) stimulation (1.9 times) of DHO production in microsomal fraction and the specific P4501A inhibitor ,-naphthoflavone significantly (P < 0.01) decreased (twice) the induced reduction activity. Cytochrome P4501A participates in oracin reduction in microsomes. 18,-Glycyrrhetinic acid, a specific inhibitor of hydroxysteroid dehydrogenase, significantly (P < 0.01) inhibited the production of DHO in the microsomal fraction (>95% inhibition) in comparison with the non-inhibited reaction. Statistically significant (P < 0.01) inhibition (95%) of DHO formation was caused by metyrapone, which is also the substrate of 11,-hydroxysteroid dehydrogenase. The main microsomal enzyme which catalyses the carbonyl reduction of oracin is probably 11,-hydroxysteroid dehydrogenase. Important oracin reduction to DHO in the cytosolic fraction was found. According to its specific sensitivity towards quercitrin (inhibition by 99%, P < 0.01), the enzyme responsible for DHO formation in the rat liver cytosol is postulated to be carbonyl reductase. [source] | ||||||||||