Hansch analysis of veratric acid derivatives as antimicrobial agents.

The synthesis, characterization and antimicrobial evaluation of a new series of veratric acid derivatives are presented. Preliminary in vitro antimicrobial activity of the title compounds was assessed against a panel of microorganisms including Gram-positive and Gram-negative bacteria and fungi. Some of the veratric acid derivatives exhibited significant in vitro antimicrobial activity. QSAR investigation applied to find a correlation between different physicochemical parameters of the veratric acid derivatives and their antimicrobial activity indicated the importance of topological parameters in describing the antimicrobial activity.

Quantitative structure-activity relationship studies for prediction of antimicrobial activity of synthesized 2,4-hexadienoic acid derivatives.

A new series of 2,4-hexadienoic acid derivatives (S(1)-S(42)) has been synthesized and evaluated as antimicrobial agents against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Candida albicans, and Aspergillus niger. Quantitative structure-activity relationship (QSAR) investigation using Hansch analysis was applied to find out correlation between antimicrobial activities with physicochemical properties of the synthesized compounds. Various physicochemical descriptors and experimentally determined minimum inhibitory concentration values for different microorganisms were used as independent and dependent variables, respectively. The QSAR revealed that topological parameters especially molecular connectivity indices (chi(2), (0)chi(v), (2)chi(v)) were found to have overall significant correlation with antimicrobial activity of 2,4-hexadienoic acid derivatives. The statistical results of training set, cross-validated r(2) and conventional r values gave reliability to the prediction of molecules with activity using QSAR models.