Structural elucidation and bioassays of newly synthesized pentavalent antimony complexes

Antimony (V) organometallics (1-5) have been synthesized with general formula [SbR'(3)(O2CR)(2)], where R' phenyl, p-tolyl and O2CR are substituted cinnamates. These complexes have been characterized by FT-IR analysis, multinuclear (H-1, C-13) NMR spectroscopy and single crystal X-ray diffraction analysis. The crystal structures of [Sb(phenyl)(3)(4-ClC6H4C2H2O2C)(2)] (1) and [Sb(p-tol)(3)(4-OCH3C6H4C2H2O2C) 2]. CHCl3 (5) displayed distorted geometry between trigonal bipyramidal and square pyramidal with monomeric structure at a five coordinated Sb center. Starting reagents and complexes were evaluated for anticancer, antileishmanial, antibacterial and alpha amylase inhibition potentials. It was observed that complexes 3, 4 and 5 showed significant (p < 0.05) antileishmanial and anticancer activities against Leishmania tropica KWH23 promastigotes and HepG2 cell lines respectively. Antibacterial activity of compound 3 was also significant against E. coli (MIC: 5.55 mg/mL), K. pneumoniae (MIC: 16.66 mg/mL), S. aureus (MIC: 5.55 mg/ mL) and P. aeruginosa (MIC: 50 mg/mL). Hence, these new antimony complexes can act as good drug candidates. (C) 2017 Elsevier B. V. All rights reserved.