Coumarin based yellow emissive AIEE active probe: A colorimetric sensor for Cu2+ and fluorescent sensor for picric acid.

A hydrazine derived ESIPT active Schiff base, 1-(8-methanylylidene-7-hydroxy-4-methyl-2H-chromen-2-one)-2-(2, 4-dihydroxybenzylidene) hydrazine, L was synthesized and characterized by elemental analysis and by various spectroscopic techniques. L exhibited a colourimetric response towards Cu2+ ion by changing from colorless to yellow with relatively a little or no interference of other common metal ions. The probe also showed good response for the detection of Cu2+ in real water samples. The H-aggregated L displayed AIEE property in acetonitrile/water mixture. The restriction of molecular motions endued the luminogen with a yellow fluorescence through ESIPT emission at 562 nm having relatively large Stock's shift of 205 nm. The scanning electron microscopic study was carried out to investigate the morphology of the nanoaggregate. The aggregated luminogen displayed it yellow emission in the pH range of 4-7 without affecting the intensity. The applicability of the probe for the detection of picric acid was also checked.

Cytotoxic and Antitumour Studies of Acetoacetanilide N(4)-methyl(phenyl)thiosemicarbazone and its Transition Metal Complexes.

Cytotoxic activities of acetoacetanilide N(4)-methyl(phenyl)thiosemicarbazone (L2H) and its seven different metal complexes were studied. Of these, IC50 value of the copper complex was found to be 46 µg/ml. Antitumour studies of this copper complex was carried out using Daltons Lymphoma Ascites cell-induced solid tumour model and Ehrlich's Ascites Carcinoma cell-induced ascites tumour model. Administration of the copper complex at different concentrations (10, 5 and 1 mg/kg b. wt) inhibited the solid tumour development in mice and increased the mean survival rate and the life span of Ascites tumour bearing mice in a concentration dependent manner.

Spectral and thermal characterization of 3-acetyl-5-azophenyl-4-hydroxy-6-methyl-pyran-2-one and its metal complexes.

Five chelates of 3-acetyl-5-azophenyl-4-hydroxy-6-methyl-pyran-2-one (phenylazo dehydroacetic acid) with Cr(III), Fe(III), Ni(II), Cu(II) and Zn(II) have been synthesized and characterized by elemental analysis, magnetic susceptibility measurements, electronic, (1)H NMR, FAB mass, IR-spectral and thermal (TG/DTG) analytical techniques. In the present work it has been found that oxygen of the deprotonated OH group and one of the azo-nitrogens of the ligand take part in coordination. The Cr(III), Fe(III) and Ni(II) complexes were found to be having octahedral geometry and the Cu(II) and Zn(II) tetrahedral.

Synthesis, characterization, and antifungal studies of transition metal complexes of omega-bromoacetoacetanilide isonicotinylhydrazone.

Isonicotinic acid hydrazide or isonicotinylhydrazide, commonly known as isoniazid, is an antibacterial agent that has been used to treat tuberculosis. It interacts with microbial cell walls. Schiff's bases or anils are the compounds having >C=N-N< linkages, which have immense applications as catalysts, stabilizers, pigments, dyes, and drugs. They have good ability to form chelates with many metal ions. Isoniazid can form Schiff's bases with diketones such as acetoacetanilide. Acetoacetanilide isonicotinylhydrazone and its metal chelates exhibit anticancer activity. Our studies on N-methylacetoacetanilide isonicotinylhydrazone and its metal chelates revealed that they are active against pathogenic fungal strains. Hence, it is worthwhile to synthesize new complexes of ligands having different substituents on the acetoacetanilide moiety. We synthesized five new metal chelates of omega-bromoacetoacetanilide isonicotinylhydrazone. The ligand behaved as a tridentate monoanion or as a tridentate dianion in the complexes. These compounds were characterized mainly by elemental analysis; conductivity measurements; and electronic, infrared, and nuclear magnetic resonance spectral studies. We also carried out antifungal studies of these compounds against four selected pathogenic fungal strains using a cup-plate technique. Both the ligand and its metal chelates were active against all fungal strains investigated. However, the chelates were found to be more active than the ligand.

Synthesis, characterization and antitumour studies of metal chelates of N1-isonicotinoyl-3-methyl-4-(p-hydroxybenzilidene)-2-pyrazolin -5-one.

The cobalt(II), nickel(II) and copper(II) complexes of N1-isonicotinoyl-3-methyl-4-(p-hydroxybenzilidene)-2-pyrazolin+ ++-5-one (IMHBP) with different counter anions have been prepared and characterized. An octahedral geometry has been assigned to the cobalt(II) and nickel(II) complexes and a square-planar structure to the copper(II) complexes. IMHBP acts as a neutral bidentate ligand in all these complexes by coordinating through the oxygen atoms of the amide group and carbonyl at position-5. The other coordination sites are satisfied by anions alone or anions and water molecules. The ligand and the complexes were screened for their possible antitumour activity. The copper(II) complexes are appreciably active in reducing mice tumours.