QSAR analysis on Spodoptera litura antifeedant activities for flavone derivatives

P. R. DUCHOWICZ; M. GOODARZI; M.A. OCSACHOQUE; G. P. ROMANELLI; E.V.ORTIZ; J.C. AUTINO; D.O. BENNARDI; D. RUIZ; E. CASTRO

SCIENCE OF THE TOTAL ENVIRONMENT

ELSEVIER SCIENCE BV

Año: 2009 vol. 408 p. 277 - 285

0048-9697

We establish useful models that relate experimentally measured biological activities of compounds to theirmolecular structure. The pED50 feeding inhibition on Spodoptera litura species exhibited by aurones,chromones, 3-coumarones and flavones is analyzed in this work through the hypothesis encompassed in theQuantitative Structure-Activity Relationships (QSAR) Theory. This constitutes a first necessary computationallybased step during the design of more bio-friendly repellents that could lead to insights for improvingthe insecticidal activities of the investigated compounds.After optimizing the molecular structure of each furane and pyrane benzoderivative with the semiempiricalmolecular orbitals method PM3, more than a thousand of constitutional, topological, geometrical andelectronic descriptors are calculated and multiparametric linear regression models are established on theantifeedant potencies. The feature selection method employed in this study is the Replacement Method,which has proven to be successful in previous analyzes. We establish the QSAR both for the completemolecular set of compounds and also for each chemical class, so that acceptably describing the variation ofthe inhibitory activities from the knowledge of their structure and thus achieving useful predictive results.The main interest of developing trustful QSAR models is that these enable the prediction of compoundshaving no experimentally measured activities for any reason. Therefore, the structure-activity relationshipsare further employed for investigating the antifeedant activity on previously synthesized 2-,7-substitutedbenzopyranes, which do not pose any measured values on the biological expression. One of them, 2-(α-naphtyl)-4H-1-benzopyran-4-one, results in a promising structure to be experimentally analyzed as it haspredicted pED50= 1.162.