Spectral studies and in vitro bio-potential of new Organotin(IV) complexes of 2-Benzyl-2-Maleimido acetic acid

Five new diorganotin(IV) complexes of 2-benzyl-2-maleimido acetic acid containing oxygen as donor atom, have been synthesized. The binding sites of the ligand were determined by means of spectroscopic techniques, like FT IR and Sn-119m Mossbauer in the solid and multinuclear NMR (H-1, C-13 & Sn-119) in the solution state. The spectroscopic data indicated trans-octahedral geometry, which was also confirmed by mass spectrometric results and supported by elemental analysis. These complexes were tested in vitro against various human pathogenic fungi, local Pakistani leishmanial strains and seven tumoural cell lines of human origin and found to be active. Complexes 4 and 5 showed higher toxicity when compared with 1-3 and ligand 6. The effect of nature (alkyl/phenyl/aryl) and size of covalently attached R'groups of organotin(IV) moieties over the toxicity of the complexes have also been investigated and correlated with the partition coefficients of the complexes between organic/aqueous solvent system.