Synthesis, structure characterization and larvicidal activity of some tris‐(para‐substitutedphenyl)tins

A series of tris‐(para‐substitutedphenyl)tins (X − C6H4)3SnY, where X = Cl, F, CH3 and SCH3 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 five‐coordinated 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 SCH3 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.