Antimicrobial effect of some organotin (IV) derivatived of propan-1, 3-dioic acid

Abstract

Three organotin (IV) derivatives of propan-1,3-dioic acid; potassium dibutyltin(IV)propan-1;3-dioate (1), potassium diphenltin(IV)propan-1;3-dioate (2), and potassium triphenltin(IV)propan-1,3-dioate (3) were synthesized mechanochemically. KOH was ground with propan-1,3-dioic acid to give the ligand L: potassium propan-1,3-dioate, followed by complexation of the ligand, L with Bu₂SnO, Ph₂SnO and Ph₃SnOH separately. Characterization of the ligand and complexes was done using magnetic susceptibility and Scanning Electron Microscopy (SEM). Ligand and complexes were screened for antimicrobial activity against five strains of gram-positive bacteria: Methicillin Resist Staph aureus, Vancomycin Resist enterococci, Staphylococcus aureus, Streptococcus pyogenes and Bacillus cereus and five fungi strains: Aspergillus fumigatus, Aspergillus flavus, Aspergillus nigre, Fusarium oxysporum and Fusarium proliferatum. Ciproflxacin and Ketoconazole were used as controlled drugs. Magnetic susceptibility data revealed complexes (1), (2) and (3) to be paramagnetic with values 0.144 μeff, 0.149 μeff and 0.151 μeff, respectively. SEM revealed that complex (3) pores were better filled by metals than complex (1) during complexation of parent organotin (IV) compound with the ligand, L. Antimicrobial result showed that the complexes synthesized in general exhibited significant activity (20-27 mm) against the microbes at the minimum inhibition concentrations (MIC) in the range 2.5 - 5 μg/mL (gram-positive bacteria) and 5 μg/mL (fungi) and minimum bactericidal/fungicidal concentrations (MBC/MFC) of 5 - 20 μg/mL/10 - 20 μg/mL. The complexes and ligand showed better antimicrobial effect against test microbes at than the control drugs. These complexes hold promise as antibacterial and antifungal agents that may be used as metal-base drugs/formulations.