Synthesis, characterization, in vitro antimicrobial and QSAR studies of diorganotin(IV) complexes of Schiff bases derived from 2-(3-methylbutanoyl)-1H-indene-1,3(2H)-dione and 4-substituted anilines

A series of some new diorganotin(IV) complexes [R2SnLCl] was synthesized by the reaction of 2-(3-methylbutanoyl)-1H-indene-1,3(2H)-dione and 4-substituted anilines (p-OCH3, p-NO2, p-CH3, p-Cl) with R2SnCl2, (R=Me, Et, n-Bu, Ph) in 1:1 molar ratio. The structure of the Schiff bases and their complexes were characterized by IR, C-13, H-1, Sn-119 NMR, and mass spectral techniques. The synthesized ligands and derived organotin complexes were evaluated in vitro against some bacterial strains, viz., Escherichia coli, Pseudomonas aeruginosa, Bacillus cereus, Staphylococcus aureus and fungal strains, viz., Aspergillus flavus, Aspergillus niger, and Candida albicans by serial dilution method. The antimicrobial results revealed that organotin complexes showed a distinct escalation in biocidal activity. Phenyl and butyl complexes were found to be more intoxicating. Furthermore, we performed QSAR studies which explained the different factors affecting the enhancement in the bioactivity of the complexes. [GRAPHICS] .