Guanidine based copper(II) complexes: synthesis, structural elucidation, and biological evaluation

Cu(II) complexes of substituted Guanidines having common formula [kappa(2)(O, N)-C6H5CONHC(NHR1)NR2](2)Cu(II), in which R-1 = C6H5- and R-2 = C(CH3)(3) (1), CH2CH2CH3 (2), CH(CH3)(2) (3), 2, 6-Cl2C6H3 (4) and 4-CH3C6H4 (5) were synthesized and their structural and chemical characteristics were examined by CHN analyzer, FTIR, NMR Spectrometer (including H-1 and C-13) and magnetic susceptibility balance. Two of the guanidine ligands and their Cu(II) complexes were also analyzed by single crystal X-ray diffraction. The X-ray diffraction analysis revealed that majority of the studied guanidine ligands were stable due to intermolecular and intra-molecular hydrogen bonding. The synthesized compounds are mononuclear having pseudo square planar geometry, whereas guanidine ligands attached to the metal center via oxygen and nitrogen atoms. The metallodrugs demonstrated better urease inhibition action than their parent guanidine ligands and also have shown fairly good score regarding the potato disk bioassay in comparison with the vincristine, employed as a standard drug.

Automated summary

In this study, Cu(II) complexes of substituted guanidines were synthesized and characterized using various analytical techniques. X-ray diffraction analysis revealed the stability of guanidine ligands due to hydrogen bonding. The synthesized compounds exhibited better urease inhibition activity than the parent guanidine ligands and showed good scores in the bioassay compared to the standard drug vincristine.