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Three ruthenium(II) polypyridyl complexes, [Ru(phen)(mip)](ClO) (1) (phen =1,10-Phenanthroline), [Ru(bpy)(mip)](ClO) (2) (bpy = 2,2'bipyridyl) and [Ru(dmb)(mip)](ClO) (3) (dmb = 4, 4'-dimethyl 2, 2'-bipyridine), were synthesized with an intercalative ligand mip (2-morpholino-1H-imidazo[4,5-f][1, 10]phenanthroline) and characterized by H,C-NMR, IR, UV-vis, mass spectra and elemental analysis. pH effect, ion selectivity (cations, anions) and solvent sensitivity of complexes were studied. The interaction of these complexes with DNA was performed using absorption, emission spectroscopy and viscosity measurements. The experimental results indicated that the two complexes interacted with calf thymus DNA (CT-DNA) by intercalative mode. BSA (Bovine Serum Albumin) protein binding of these complexes was studied by UV-visible and fluorescence techniques. The binding capacity of these complexes was explained theoretically by molecular docking method.

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The three Ru(II) complexes of [Ru(phen)(2)dppca](2+) (1) [Ru(bpy)(2)dppca](2+) (2) and [Ru(dmb)(2)dppca](2+) (3) (where phen = 1,10 phenanthroline, bpy = 2,2-bipyridine, dmb = 2 ,2-dimethyl 2',2'-bipyridine and polypyridyl ligand containing a single carboxylate functionality dppca ligand (dipyridophenazine-11-carboxylic acid) have been synthesized and characterized. These complexes have been shown to act as promising calf thymus DNA intercalators and a new class of DNA light switches, as evidenced by UV-visible and luminescence titrations with Co(2+) and EDTA, steady-state emission quenching by [Fe(CN)(6)](4-) and KI, DNA competitive binding with ethidium bromide, viscosity measurements, and DNA melting experiments. The results suggest that 1, 2, and 3 complexes bind to CT-DNA through intercalation and follows the order 1 > 2 > 3. Under irradiation at 365 nm, the three complexes have also been found to promote the photocleavage of plasmid pBR322 DNA.

NiÀ Al-Ti mixed oxide derived from NiÀ Al-Ti hydrotalcite precursor is identified as an efficient catalyst for the hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL). This catalyst showed high active surface Ni sites due to a higher synergy in the mixed oxide formed from the hydrotalcite precursor. These results are further supported by X-ray diffraction analysis (XRD), electron spin resonance spectroscopy (ESR) and scanning electron microscopy (SEM) results. The higher activity of NiÀ Al-Ti compared to NiÀ Al, NiÀ Ti catalysts was attributed to a high ratio of Lewis to Brønsted acid sites (LAS/BAS) observed from pyridine adsorption -DRIFTS results along with high surface Ni sites on the catalyst surface measured from CO-chemisorption studies. This contributed to the enhanced selectivity of the desired product, GVL over NiÀ Al-Ti catalyst as compared to its individual counter parts, NiÀ Ti and NiÀ Al catalysts.[a] R.