Synthesis, structure and antibacterial activity of some triorganotin(IV) complexes with a benzamidoalanine ligand

New triorganotin(IV) complexes of the type PhSnL3, BuSnL3 and MeSnL3 were constructed with the ligand benzamidoalanine, which was formed by reaction of benzoyl chloride with alanine in the presence of sodium hydroxide. The complexes were characterized by elemental analysis, conductance measurements and infrared, ultraviolet visible and 1H, 13C and 119Sn nuclear magnetic resonance spectroscopy. Monomer structures were proposed from the spectral measurements, with a bidentate form. All compounds were screened for antibacterial (Staphylococcus aureus ATCC-9144, S. epidermidis ATCC-155, Micrococcus luteus ATCC-4698, Bacillus cereus ATCC-11778, Escherichia coli ATCC-25922 and Pseudomonas aeruginosa ATCC-2853) and antifungal (Aspergillus niger ATCC-9029 and A. fumigatus ATCC-46645) activity by paper disc diffusion. The minimum inhibitory concentrations of the compounds were determined by agar streak dilution. MeSnL3 was the most potent antimicrobial agent when compared with ciprofloxin and ketoconazole.We describe here a simple, convenient route for synthesizing new organotin derivatives for antimicrobial evaluation.