Biocatalysis in Organic Synthesis

Abstract

Application of enzymatic processes to the synthesis of homochiral intermediates possessing one or more stereogenic elements will be the main focus of this project. Monitoring microorganisms available in brazilian culture collections will allow the detection of novel biocatalytic activities, mainly from enzymes belonging to oxide-reductases, hydrolases and laccases type. With this proposal we are continuing the current projects of our research group and it will be possible to employ microorganisms with enzymatic systems with high enantioselectivity in kinetic resolutions or in symmetric inductions. Within the subjects that will be studied, but not excluding any, since we will be attentive to new opportunities which may be happening during the time of the project, we indicate: 1) bioreduction of ketones, using mainly whole cells of fungi and yeasts; 2) bioreduction of conjugated alkenes with electro-withdrawing groups; 3) bio-oxidation of allylic hydrocarbons. The chosen substrates will be low molar mass molecules and most of them are commercially available with low added value. This strategy will allow bioreduction to add value through the generation of chirality centers, obtaining products with pharmacological proprieties, new agrochemicals and intermediates for chemical specialties. The collaboration with microbiologists and biochemists is essential to fully develop this project that has interfaces between Chemistry and Biology. The isolation of enzymes of interest will be theme of future work, or even in parallel to this one. When necessary, we have to increase the enzymatic activity using, methodologies available to improve the enantioselectivity of the bioreactors. For enantiomeric excess determinations it will be necessary to carry out simultaneously reactions with raceme chemicals. With this strategy, we may have to use new methodologies and we will be attentive to any opportunity to study new reactions. (AU)