Quantitative structure activity relationships for the nematicidal activity of 4-amino-5-substituted aryl-3-mercapto-(4<i style="">H</i>)-1,2,4-triazoles

Abstract

The relationship between the structure of a series 4-amino-5-substituted aryl-3-mercapto-(4<i style="">H</i>)-1,2,4-triazoles and their nematicidal activity against <i style="">Meloidogyne incognita</i> and <i style="">Rotylenchulus reniformis</i> has been analyzed using physicochemical parameters for hydrophobic, electronic and steric properties of the molecules by means of multiple regression analysis. The activity of the compounds predicted based on the QSAR models has been found comparable with the experimental values. The QSAR study reveals that the nematicidal activity against both nematodes is dependent on the electronic effect of <i style="">ortho</i> substituent [<img src='/image/spc_char/sum.gif' border=0>F], bulkiness of <i style="">para</i> substituent [<img src='/image/spc_char/sum.gif' border=0>MR (p)] and width of meta substituent [B4 (m)] of benzene ring substituents. The higher values of these parameters are favourable for nematicidal activity.