The tri-n-butyltin(IV) complexes of 2-[(E)-2-(3-formyl-4-hydroxyphenyl)-1-diazenyl]benzoic acid and 4-[((E)-1-{2-hydroxy-5-[(E)-2-(2-carboxyphenyl)-1-diazenyl]phenyl}methylidene)amino]aryls (aryls = 4-CH 3 , 4-Br, 4-Cl, 4-OCH 3 ) have been synthesized and characterized by 1 H, 13 C, 119 Sn NMR, IR and 119m Sn Mö ssbauer spectroscopic techniques in combination with elemental analysis. The crystal structures of two compounds, (Bu 3 Sn[O 2 CC 6 H 4 {N@N(C 6 H 3 -4-OH-5-CHO)}-o]) n and (Bu 3 Sn[O 2 CC 6 H 4 -{N@N(C 6 H 3 -4-OH(C(H)@NC 6 H 4 Cl-4))}-o]) n , are reported.The crystallographic and 119 Sn Mö ssbauer data both indicate that the tributyltin complexes form single-stranded polymeric structures in which the carboxylate O atoms of each aryl ligand bridge two Sn atoms. The Sn atoms have a slighly distorted trigonal bipyramidal coordination geometry with equatorial butyl groups and carboxylate O atoms occupying axial positions. The 119 Sn NMR spectroscopic data and the 1 J( 13 C-119/117 Sn) coupling constant indicate a tetrahedral coordination geometry in non-coordinating solvents. The results of a toxicity study of a tributyltin compound on the second larval instar of Aedes aegypti mosquito larvae are reported.

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A series of triorganotin 2,2,3,3-tetramethylcyclopropanecarboxylates, where R = methyl, ethyl, npropyl, n-butyl, phenyl and cyclohexyl, have been synthesized. Elemental analysis, Mössbauer, infrared and NMR spectroscopies were used to characterize their structures. Based on the spectroscopic results, all the complexes in the solid state with the exception of the tricyclohexyl compound were found to be five-coordinated, while the tricyclohexyltin derivative was determined to be fourcoordinated. Based on the NMR results, all the complexes in solution have a tetrahedral configuration. Larvicidal activities of the complexes were evaluated against the second instar stage of the Aedes aegypti, Anopheles stephensi and Culex pipiens quinquefasciatus mosquitoes. The toxicity results indicated that this series of triorganotins are effective larvicides against all three species of larvae. In addition, quantitative structure-activity relationships (QSARs) were also developed for each species of larvae.

A series of tributyltin(IV) complexes of 2-[(E)-2-(3-formyl-4-hydroxyphenyl)-1-diazenyl]benzoic acid and 4-[((E)-1-{2-hydroxy-5-[(E)-2-(2-carboxyphenyl)-1-diazenyl]phenyl}methylidene)amino]aryls have been investigated by electrospray mass spectrometry (ESI-MS) and tandem mass spectrometry (MS

A series of tris-(para-substitutedphenyl)tins (X − C 6 H 4 ) 3 SnY, where X = Cl, F, CH 3 and SCH 3 and Y = Cl, OH and OAc, was synthesized. The structures of the compounds were primarily characterized by Mössbauer spectroscopy. Based on the spectroscopic data, the chloride derivatives were determined to be four-coordinated monomers and the acetate and hydroxide compounds were found to be fivecoordinated polymers. The compounds were screened against the second larval instar of the Anopheles stephensi and Aedes aegypti mosquitoes. For the An. stephensi larvae, the compounds that had the highest toxicity were those that contained a single atom substituent on the phenyl ring, and the least effective compounds contained the SCH 3 substituent. Toxicity was more dependent on the ring substituent than on the anion attached to the tin atom. Quantitative structure-activity relationships could be generated between the toxicity of the compounds and the surface area of the molecule, indicating that the toxicity was related to the size of the substituent on the ring. In the case of the Ae. aegypti, the toxicity was also more dependent on the ring substituent than on the anion group. However, the size of the substituent on the ring was not found to be the dominant factor in the toxicity of these compounds.