Synthesis, characteristic spectral studies and in vitroantimicrobial and antitumour activities of organotin(IV) complexes of Schiff bases derived from amino‐acids

Equimolar reactions of dibutyltin(IV) oxide with Schiff bases derived from amino‐acids led to the formation of a new series of dibutyltin(IV) complexes of general formula, Bu2SnL [L=dianion of tridentate Schiff bases derived from the condensation of 2‐hydroxy‐1‐naphthaldehyde or acetyl acetone with glycine (L‐1), L‐β‐alanine (L‐2), DL‐valine (L‐3), DL‐4‐aminobutyric acid (L‐4), L‐methionine (L‐5), L‐leucine (L‐6) and phenylglycine (L‐7)]. An attempt has been made to prove the structures of the resulting complexes on the basis of elemental analyses, conductance measurements and electronic, IR, multinuclear magnetic resonance (1H, 13C and 117Sn) and 119Sn Mössbauer spectral studies. The complexes have been tested against various bacteria [Streptococcus faecalis,Klebsiella pneumoniae,Escherichia coli,Pseudomonas aeruginosa,Staphylococcus aureuspenicillin resistance (2500 units)] and fungi (Candida albicans, Cryptococcus neoformans,Sporotrichum schenckii,Trichophyton mentagrophytesand Aspergillus fumigatus). All the complexes showed moderate activity. The cytotoxicity of a few compounds has been screened in vitroagainst seven human tumour cell lines, viz. MCF‐7, EVSA‐T, WiDr, IGROV, M19 MEL, A498 and H226. The activities found experimentally were better than those obtained for cisplatin and carboplatin © 1997 John Wiley & Sons, Ltd.