Synthesis, structure and biological activity of triorganotin 1H‐tetrazolyl‐1‐acetates: cyclic hexamer and linkage coordination polymers

Reaction of 1H-tetrazolyl-1-acetic acid (CHN4CH2CO2H) with (R3Sn)2O or R3SnOH yields triorganotin 1H-tetrazolyl-1-acetates [CHN4CH2CO2SnR3, R = Ph (1), p-tolyl (2), cyclohexyl (3), n-Bu (4) and Et (5)]. 1H-tetrazolyl-1-acetates in these triorganotin derivatives display remarkably different coordination modes, depending on the properties of the organic substituents bonded to the tin atoms. Complex 1 displays a rare cyclohexameric structure by the assembly of the SnN coordination bond, while complex 2 forms a linkage coordination polymer through the intermolecular Sn···N interactions. The structure of complex 3 is similar to that of complex 2, but the intermolecular Sn···N interactions are weaker in the former. However, in complex 4, the tetrazolyl nitrogen atoms do not coordinate to the tin atoms. This complex forms a polymeric chain by the unsymmetric bridging carboxylate group. All these complexes exhibit good antifungal activities in vitro against Alternaria solani, Cercospora arachidicola, Gibberella zeae, Physalospora piricola and Botrytis cinerea. The corresponding EC50 values of these complexes were tested. Copyright © 2009 John Wiley & Sons, Ltd.