Five New Cu(II) complexes, [bis(1-amidino-O-alkylurea) Cu(II) tartrate], where alkyl=methyl (1), ethyl (2), n-propyl (3), n-butyl (4), or iso-butyl (5) have been synthesized and characterized. The electron paramagnetic resonance spectra of complexes 1 and 2 showed features of mononuclear species whereas complexes 3, 4, and 5 in frozen DMSO solution show the existence of mononuclear and binuclear species in these complexes. Complexes crystallize in a monoclinic structure. The binding of these complexes with calf thymus DNA suggested that these complexes interact with DNA by electrostatic or groove binding, not by intercalation. These complexes are also found to have good antimicrobial activity.

Copper(II) complexes of [Cu(II)(1-amidino-O-2-methoxyethylurea)2]Cl2 (1) and [Cu(II)(1-amidino-O-2-ethoxyethylurea)2]Cl2 (2) have been synthesized and characterized by elemental analysis, magnetic moment, conductance, thermal analysis, IR, UV, powdered XRD and EPR spectral studies. The trend in g values g || > g ⊥ > 2.0023 in the EPR spectra of the complexes suggest that the unpaired electron on copper(II) ion has \({d_{x}}^2 - {{}_{y}}^2\) character and the complexes have square planar structure which is also supported by electronic absorption spectral studies. The bonding parameters of these complexes in DMF have been calculated based on the EPR and electronic spectral data. The complexes (1) and (2) exhibit K || > K ⊥ which indicates the presence of significant out-of-plane π bonding. Powdered XRD spectral patterns show that complexes crystallize in a monoclinic system. The binding of the complexes with calf thymus DNA was investigated by absorption and emission spectroscopy, viscosity measurements, DNA melting and cyclic voltammetric studies. DNA interaction studies show that the complexes bind to calf thymus DNA in a non-intercalative mode. The two complexes exhibit growth inhibitory activity against pathogenic bacteria, viz., Escherichia coli, Klebsiella pneumoniae sub sp. Pneumoniae, Proteus mirabilis.

The isolation of coumarin, beta-sitosterol and beta-sitosterol-D-glucoside from the chloroform extract; and o-coumaric acid, cerebroside 1, ceramide 2, and quercetin-3-o-rutinoside 3 from the methanol extract of the leaves of Eupatorium birmanicum DC. along with the antifungal study of the chloroform and methanol extracts from the plant are reported. The structures of the isolated compounds are characterized by different spectroscopic methods.