Spectral studies and in vitro antimicrobial activity of new organotin(IV) complexes of Schiff bases derived from amino acids

Some new di- and triphenyltin(IV) complexes of the general formulae Ph2SnL and Ph3SnL', where H2L/HL' = Schiff bases derived from the condensation of 2-hydroxy-1-naphthaldehyde (H2L) and benzaldehyde (HL') with glycine (H2L-1/HL'-1), DL-alpha-alanine (H2L-2/HL'-2), L-methionine (H2L-3/HL'-3), DL-valine (H2L-4/HL'-4), D-phenylalanine (H2L-5/HL'-5), 2-aminobutyric acid (H2L-6/HL'-6), and L-leucine (H2L-7/HL'-7), have been synthesized and characterized by elemental analyses, molar conductance, electronic, infrared and far-infrared, multinuclear magnetic resonance (H-1, C-13, and Sn-117), and Sn-119 Mossbauer studies. Thermal decomposition of a few complexes using TG, DTG, and DTA techniques indicates the formation of SnO2 as a residue. The complexes have also been tested in vitro against bacteria [Streptococcus faecalis, Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus Penicillin resistance (2500 units)] and fungi [Candida albicans, Cryptococcus neoformans, Sporotrichum schenckii, Trichophyton mentagrophytes, and Aspergillus fumigatus]. All of the complexes show remarkable activity.