Investigation of antileishmanial, antioxidant activities, CT-DNA interaction and DFT study of novel cobalt(II) complexes derived from mesogenic aromatic amino acids based Schiff base ligands.

In the present work, new Co(II) complexes were synthesized from mesogenic aromatic amino acids based Schiff base ligands, HL [Methyl 2-((2-hydroxy-4-(tetradecyloxy)benzylidene)amino)-3-phenylpropanoate] and HL [Methyl 2-((2-hydroxy-4-(tetradecyloxy)benzylidene)amino)-3-(1H-indol-2-yl)propanoate]. The compounds were thoroughly characterised using different elemental, thermogravimetric and spectroscopic studies. The in-vitro antileishmanial efficacy of the compounds against Leishmania donovani was evaluated by MTT assay and the antioxidant activity was performed by Mensor's method.

Fluorescence Behavior of Schiff Base-N, N'-bis(salicylidene) Trans 1, 2-Diaminocyclohexane in Proteinous and Micellar Environments.

Fluorescence properties of N, N'-bis(salicylidene) trans 1, 2-diaminocyclohexane (H L) is used to probe the anionic (SDS), cationic (CTAB) and nonionic (TX-100) micelles as well as in serum albumins (BSA and HSA) and chicken egg white lysozyme (LYZ) by steady state and picosecond time-resolved fluorescence spectroscopy. The fluorescence band intensity was found to increase with concomitant blue-shift with gradual addition of different surfactants. All the experimental results suggest that the probe molecule resides in the micelle-water interface rather than going into the micellar core.

Coumarin Based Fluorescent Probe for Colorimetric Detection of Fe and Fluorescence Turn On-Off Response of Zn and Cu.

A new coumarin based Schiff-base chemosensor-(E)-7-(((8-hydroxyquinolin-2-yl)methylene) amino)-4-methyl-2H-chromen-2-one (H L) was synthesized and evaluated as a colorimetric sensor for Fe and fluorescence "turn on-off" response of Zn and Cu using absorption and fluorescence spectroscopy. Upon treatment with Fe and Zn, the absorption intensity as well as the fluorescence emission intensity increases drastically compared to other common alkali, alkaline earth and transition metal ions, with a distinct color change which provide naked eye detection. Formation of 1:1 metal to ligand complex has been evaluated using Benesi-Hildebrand relation, Job's plot analyses, H NMR titration as well as ESI-Mass spectral analysis.

Fluorescence properties of Schiff base - N,N'-bis(salicylidene) - 1,2-Phenylenediamine in presence of bile acid host.

Fluorescence properties of Schiff base - N,N'-bis(salicylidene) - 1,2-phenylenediamine (LH2) is used to study the micelles formed by aggregation of different important bile acids like cholic acid, deoxycholic acid, chenodeoxycholic acid and glycocholic acid by steady state and picosecond time-resolved fluorescence spectroscopy. The fluorescence band intensity was found out to increase with concomitant red shift with gradual addition of different bile acids. Binding constant of the probe with different bile acids as well as critical micelle concentration was obtained from the variation of fluorescence intensity on increasing concentration of bile acids in the medium.

A highly sensitive and selective fluorescent chemosensor for detection of Zn2+ based on a Schiff base.

A Schiff-base fluorescent probe - 2-((E)-(quinolin-8-ylimino)methyl)quinolin-8-ol (H7L) was synthesized and evaluated as a chemoselective Zn2+ sensor. Upon treatment with Zn2+, the complexation of H7L with Zn2+ resulted in a red shift with a pronounced enhancement in the fluorescence emission intensity in ethanol solution. Moreover, other common alkali, alkaline earth and transition metal ions failed to induce response or minimal spectral changes.

A sensitive Schiff-base fluorescent chemosensor for the selective detection of Zn²⁺.

A Schiff-base fluorescent probe - N, N(/)-bis(salicylidene) trans 1, 2 - diaminocyclohexane (H 2 L) was synthesized and evaluated as a chemoselective Zn(2+) sensor. Upon treatment with Zn(2+), the complexation of H 2 L with Zn(2+) resulted in a bathochromic shift with a pronounced enhancement in the fluorescence intensity in ethanol solution. Moreover, other common alkali, alkaline earth and transition metal ions failed to induce response or minimal spectral changes.

Fluorescent chemosensor based on sensitive Schiff base for selective detection of Zn2+.

A Schiff-base fluorescent compound - N, N'-bis(salicylidene)-1,2 - phenylenediamine (LH2) was synthesized and evaluated as a chemoselective Zn(2+) sensor. Addition of Zn(2+) to ethanol solution of LH2 resulted in a red shift with a pronounced enhancement in the fluorescence intensity. Moreover, other common alkali, alkaline earth and transition metal ions failed to induce response or minimal spectral changes.

Reactivity of tris(acetylacetonato) iron(III) with tridentate [ONO] donor Schiff base as an access to newer mixed-ligand iron(III) complexes.

Two new mixed-ligand iron(III) complexes, [Fe(L(n))(acac)(C(2)H(5)OH)] incorporating coordinated ethanol from the reaction solvent were accessed from the reaction of [Fe(acac)(3)] with [ONO] donor dibasic tridentate unsymmetrical Schiff base ligands derived from condensation of 2-hydroxy-1-napthaldehyde with 2-aminophenol (H(2)L(1)) or 2-aminobenzoic acid (H(2)L(2)). The thermal study (TGA-DTA) provided evidence for weakly bound ethanol which is readily substituted by neutral N-donor molecule imidazole, benzimidazole or pyridine to produce an array of newer complexes, [Fe(L(n))(acac)X] (n=1, 2; X=Im, Bim, Py). The compounds were characterized by elemental analyses, FT-IR, UV-vis, solution electrical conductivity, FAB mass, (1)H and (13)C NMR spectroscopy.

Electron Transfer. 135. Pendant Carbonyl Groups in the Mediation of the Reactions of Indium(I) with Bound Ruthenium(III)(1).

Reductions, using In(I)(aq) and Ti(III)(aq), of (NH(3))(5)Ru(III) derivatives of pyridines having carbonyl-bearing substituents (-CONH(2), -COOCH(3), and -COC(6)H(5)) yield the corresponding (NH(3))(5)Ru(II) complexes. Reactions with Ti(III) are kinetically straightforward, exhibit only slight responses to structural alteration, and give no indication of inner-sphere mediation involving the carbonyl group. Kinetic profiles for In(I) reductions of the 3-CONH(2), 3-COOCH(3), and 3-COC(6)H(5)-substituted complexes (in the range [H(+)] = 0.