Abstract

Quantitative structure-activity relationship (QSAR) studies, using the Comparative Molecular Field Analysis (CoMFA), on a series of 6,7-diarylpteridine derivatives showing nematocide properties have been carried out. The CoMFA. model generated in the study has been used to estimate the namatocide activity ((MIC50) of seven 6,7-diarylpteridines related to those previously studied. The model is highly predictive for all pteridine derivatives in the test set. Moreover, this model also predicts satisfactorily the nematocide activity of other [6]+[6] fused pyrazines (quinoxalines and pyridopyrazines) which were not represented in the training set. The analysis revealed the importance of steric factors (64.8%) and then the electrostatic ones (35.8%). Most pteridines under study were previously synthesized and tested as nematocide agents. Now, the synthesis and biological evaluation of 6,7-di-(2'-thienyl)-4(3H)-thioxo-pteridine 36 are reported.