Preparation, structural elucidation and biocidal applications of trimethyltin(IV) complexes derived from substituted carboxylic acids

A series of trimethyltin(IV) carboxylates (1-7), having general formula [(CH(3))(3)SnOOCR], where R = 3-CF(3)C(6)H(4)- (1), 3,4-(OCH(2)CH(3))(2) C(6)H(3)- (2), 3-FC(6)H(4)- (3), 4-ClC(6)H(5)- (4), 2,4-(OCH(3))(2)C(6)H(3)- (5), 4-NO(2)C(6)H(4)- (6), 5-CH(3)C(4)H(2)N(2)- (7) have been synthesized and are characterized by using analytical techniques like, FT-IR, (1)H, (13)C and (119)Sn NMR spectroscopy in addition to elemental analyses. To validate the structural motif, one of the complex (2) was also analyzed by single crystal XRD technique. The single crystal X-ray diffraction analysis revealed that the molecular species exist in one dimensional polymeric chain, wherein five coordinated tin is attached to two oxygens of the carboxyl and three carbon atoms of CH(3) groups, whereas the bond angles for C-Sn-C (117.20–121.65°), C-Sn-O (87.87–98.60°) and O-Sn-O (173.75°) lie in the predictable range of distorted trigonal bipyramidal geometry. All the synthesized complexes were also subjected to preliminary screening for various biocidal applications such as antimicrobial, anti-diabetic, protein kinase inhibition and brine shrimp lethality test to check their efficacy. The compound 6 exhibits very good antibacterial activity having MIC value 6.25 μg/mL against K. pneumoniae, whereas antidiabetic and protein kinase inhibition data revealed that 1 and 2 may serve as good to moderately effective inhibitors, respectively.