Synthesis,structural and biocidal activity studies of triorganotin(IV) compounds of some N-protected amino-acids

Seven new triorganotin(IV) complexes of the type R₃SnL (L=N-phthaloyl derivatives of glycine, DL-alanine or N-acetyl- and N-benzoyl-glycine and -cysteine; R-n-C₄H₉ or C₆H₅) have been prepared by reacting the sodium salt of the ligand and the triorganotin(IV) chloride in 1:1 molar ratio in methanol. The complexes have been characterized by elemental analysis, molecular mass determination, IR and ¹H NMR spectroscopy. The complexes are monomeric in molten camphor and are moderateely soluble in the common organic solvents. The spectral data support cis five-coordinate complexes with an unsymmetrical bidentate coordination of the carboxylate group to tin. The complexes exhibit some insecticidal effect on Bean Weevils (Sitophilus granaria) even at low concentration and they also show fungicidal activity on Aspergillus niger and Helminthosporium taulosum. Some of the complexes are found to be more effective than tri-n-butyltin and triphenyltin chlorides.