In this work, we report a theoretical study on electron collisions with OH radicals in the low and intermediate energy ranges. Calculated elastic differential, integral, and momentum-transfer cross sections as well as grand-total (elastic + inelastic) and total absorption cross sections for electron-OH collisions are reported in the 1-500-eV range. A complex optical potential composed by static, exchange, correlation-polarization plus absorption contributions, derived from a fully molecular wave function, is used to describe the interaction dynamics. The Schwinger variational iterative method combined with the distorted-wave approximation is applied to calculate scattering amplitudes. Present calculated results are compared with the existing data for electron-OH scattering in the literature. Also, comparison made between our calculated cross sections for elastic scattering with the theoretical and experimental results for electron-H 2 O collisions has revealed remarkable similarity even at incident energies as low as 2 eV.

Quantitative structure–activity relationship (QSAR) studies were performed in order to identify molecular features responsible for the antileishmanial activity of 61 adenosine analogues acting as inhibitors of the enzyme glyceraldehyde 3-phosphate dehydrogenase of Leishmania mexicana (LmGAPDH). Density functional theory (DFT) was employed to calculate quantum-chemical descriptors, while several structural descriptors were generated with Dragon 5.4. Variable selection was undertaken with the ordered predictor selection (OPS) algorithm, which provided a set with the most relevant descriptors to perform PLS, PCR and MLR regressions. Reliable and predictive models were obtained, as attested by their high correlation coefficients, as well as the agreement between predicted and experimental values for an external test set. Additional validation procedures were carried out, demonstrating that robust models were developed, providing helpful tools for the optimization of the antileishmanial activity of adenosine compounds.

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Chemometric pattern recognition techniques were employed in order to obtain Structure-Activity Relationship (SAR) models relating the structures of a series of adenosine compounds to the affinity for glyceraldehyde 3-phosphate dehydrogenase of Leishmania mexicana (LmGAPDH). A training set of 49 compounds was used to build the models and the best ones were obtained with one geometrical and four electronic descriptors. Classification models were externally validated by predictions for a test set of 14 compounds not used in the model building process. Results of good quality were obtained, as verified by the correct classifications achieved. Moreover, the results are in good agreement with previous SAR studies on these molecules, to such an extent that we can suggest that these findings may help in further investigations on ligands of LmGAPDH capable of improving treatment of leishmaniasis.