Abstract
Schiff bases derived from 5-substituted salicylidine 3-[p-(5-substituted salicylidinehydrazinocarbonyl)]phenylsydnones and their transition metal complexes with Co(II), Ni(II), Cu(II), and Zn(II) have been synthesized and characterized by elemental analysis, molar conductance, magnetic susceptibilities, electronic, infrared, Proton Magnetic Resonance (PMR) (1H NMR), Fast Atomic Bombardment-(FAB)-mass spectra, Electron Spin Resonance (ESR), and thermal studies. From the above spectral studies, it is concluded that the ligands viz., 3-[p-(salicylidinehydrazinocarbonyl)]phenylsydnone (L1 ); p-(vanillidine hydrazinocarbonyl)]phenylsydnone (L2 ); and 3-[p-(5′chlorosalicylicdinehydrazinecarbonyl)]-phenylsydnones (L3 ) act as bidentate molecules coordinating through azomethine nitrogen and phenolic oxygen. The ligands and their metal complexes have been screened in vitro for antibacterial, antifungal, and antitumor activities. The results indicate that the biological activity has increased on complexation. The Cu(II) complexes of the above-said ligands have proven to be antitumor agents toward the P388/s tumor cells at lower concentrations.
Acknowledgements
The authors are thankful to University Sophisticated Instrumentation Centre (USIC) for recording the FT-IR spectra and 1H NMR spectra. The authors extend their thanks to Central Drug Research Institute, Lucknow, for providing EI and FAB mass spectra. They also thank the Sophisticated Test and Instrumentation Centre (STIC) Cochin for providing the ESR spectra. The authors are also thankful to Dr. S.R. Pattan, Department of Pharmacology, Belgaum, for his support in carrying out the biological studies of the compounds.