Synthesis and structural investigations on R2Sn(IV)-D-aldonic acid complexes (R = methyl;butyl). Their effect on a new toxicity testorganism, Liza saliens (Osteichthyes,Mugilidae): a histological study.

Eight R2 Sn(IV)-D-aldonate complexes [(R = Me, Bu; D-aldonate = D-galactonate2− (Galn), D-Gluconate2− (Glun), D-Gulonate2−(Guln), D-Ribonate2− (Ribn)], five of which are new derivatives, have been synthesized and structurally characterized both in solidand solution state by IR, 119Sn Mossbauer and 1H, 13C, 119Sn NMR spectroscopies, showing that ligands act as dianonic chelating agents. In solution phase, NMR data suggest that the bidentate chelation is attained by the O1 carboxylate and the vicinal O2 alkoxide atoms, which can be dynamically extended to a third binding site (O4) competing with O2. In Me2 Sn(IV)-D-gluconate complex the occurrence of a self-association process leading to a dimeric species was also observed. Histopathological studies on different organs of Liza saliens showed that the dibutyltin(IV)-D-aldonate complexes, although preserving the defense immunity system, exhibit a specific toxicity on some target cells and organs. The toxicity of such complexes has been comparedwith respect to the effects of a previous study with tributyltin(IV) chloride solutions.