Self-assembled Transition Metal Coordination Frameworks of Carbohydrazone and Thiocarbohydrazone Ligands: Structural, Spectral, Magnetic and Anticancer Properties

Chemistry occupies a unique middle position in the scientific arena, between physics and mathematics on the one side and biology, ecology, sociology and economics on the other [1]. Chemistry is the science of matter and of its transformations, and life is its highest expression [2]. According to reductionist thinking biology is reducible into chemistry, chemistry into physics, and ultimately physics into mathematics. Reductionism implies the ease of understanding one level in terms of another.The work presented this thesis comprises synthesis and characterization of suitably substituted thiocarbohydrazone and carbohydrazone ligand building blocks, self-assembled metallosupramolecular square grid complexes as well as some di/multinuclear complexes. The primary aim was the deliberate syntheses of some novel transition metal framework complexes, mainly metallosupramolecular coordination square grids by self-assembly and their physico-chemical characterization. The work presented, however, also include synthesis and characterization of four mononuclear Ni(II) complexes of two thiosemicarbazones, which we carried out as a preliminary and supporting study. Based on the present work we would like to conclude that the carbohydrazones, thiocarbohydrazones and their coordination framework complexes of transition metals are promising systems for wide application in science and technology varied from physics to biotechnology. Novel classes of materials and biologically important potential compounds open up further scope of researches and we hopefully welcome any sort of related research to make this work more valuable.

Synthesis and Characterization Of Some Transition Metal Complexes Of Multidentate Ligands

Coordination chemistry of schiff bases is of considerable interest due to their various magnetic, catalytic and biological applications. Here it describes the spectral characterization of schiff bases and its Mn (II), Cu (II) and Ni (II) complexes. Then synthesis and spectral characterization of Zn (II), Cd (II) and Co (II) complexes of schiff base derived from 3-Formylsalicilic Acid and 1,3-diaminopropane. Then it discusses the synthesis and spectral studies of Copper (II) complexes of 2-Hydroxyacetophenone N-phenyl semicarbazone. Finally it discusses the synthesis and spectral characterization of Co (III) complexes of salicylaldehyde N-phenyl semicarbazone. The preparation and characterization of Cobalt (III) complexes of salicylaldehyde, N-phenylthiosemicarbazone containing hetrocyclic bases phenalthroline and bipyridine. Thiocyanate, azide and perchlorate ions act as coligands. Elemental analysis suggests +3 state for Cobalt. HNMR, IR and UV-visible spectra characterize the complexes.

Studies on the Nature and Chemistry of Sediments and Water of Periyar and Chalakudy Rivers, Kerala, India

The present study is an attempt to address issues related to sediment properties like texture, mineralogy and geochemistry as well as water quality of two important rivers of central Kerala-the Periyar and the Chalakudy rivers. The main objectives of the study are to investigate the textural and mineralogical characteristics as well as transportation and depositional mechanisms of the sediments of Periyar and Chalakudy rivers, to find out the geochemical variability of organic carbon, phosphorus and certain major (Na,K,Ca and Mg) and minor/trace(Mn,Pb,Ni,Cr, and Zn) elements in the bulk sediments and mud fraction of these rivers, to evaluate the status of heavy metal pollution registered in the sediments of these rivers, to assess the physico-chemical characteristics and water quality of Periyar and Chalakudy rivers and to estimate the dissolved nutrient flux through the Periyar and Chalakudy rivers into the receiving coastal waters. The granulometric characteristics as well as statistical parameters of the sediments of Periyar and Chalakudy rivers depend on the flow pattern controlled by the gradient of the terrain. Compared to Periyar, fluctuations in the dispersal of particles are more in Chalakudy river. In Periyar river, the P and Fe in bulk sediments show a positive correlation with C-org, while in Chalakudy river, both the elements are related to THM concentration. In general, C-org, Fe and P Shows an increasing trend downstream. In Periyar river, the P and Fe in bulk sediments show a positive correlation with C-org, while in Chalakudy river, both the elements are related to THM concentration. Among these two rivers, the pollution of water is several fold higher in Periyar river due to influx due to influx of considerable quantity of liquid and solid wastes of industrial/domestic/urban origin. Nutrient analysis reveals 2-3 times increase in N and P during monsoon season whereas SiO2-Si shows a decreasing trend.

Effect of pore size on the catalytic activities of K-I 0 clay and H-zeolites for the acetalization of ketones with methanol

One-pot acetalizations of cyclohexanone. acetophenone and benzophenone were carried out using methanol over H-montmorillonite clay (a mesoporous material). silica, alumina, and different zeolites such as HFAU-Y.HBeta, H-ZSM-5, and H-mordenite. In all the cases a single product-the corresponding dimethylacetal-was obtained in high yields. Hemiacetal formation was not observed with any catalyst. A comparison of catalytic activity indicated that montmorillonite K-10 is the most active catalyst for the reaction. As evidenced by the reaction time studies, the catalyst decay is greater over the zeolite catalyst than over the clay.

Transition metal complexes of some bis(thiosemicarbazones) derived from 2,6-diacetylpyridine and N4-substituted thiosemicarbazides:Synthesis, spectral and structural studies

Coordination chemistry of pentadentate 2,6-diacetylpyridine bis(thiosemicarbazone) Schiff base ligands has been intensively studied due to the versatility of the molecular chain in order to obtain very different geometries as well as their broad therapeutic activity. Metal complexes of thiosemicarbazone with aldehydes and ketones have been widely reported. But there have been fewer reports on potential pentadentate bis(thiosemicarbazones) formed from 2,6-diacetylpyridine. Keeping these in view, we have synthesized four bis(thiosemicarbazone) systems with 2,6-diacetylpyridine. In the present work, the chelating behavior of bis(thiosemicarbazones) are studied, with the aim of investigating the influence of coordination exerts on their conformation and or configuration, in connection with the nature of the metal and of the counter ion. The selection of the 2,6-diacetylpyridine as the ketonic part was based on its capability to form polynuclear complexes with different coordination number. The doubled armed bis(thiosemicarbazones) can coordinate to a metal centre as dianionic ligand by losing its amide protons or it can coordinate as monoanionic ligand by losing its amide proton from one of the thiosemicarbazone moiety or it can also be coordinate as neutral ligand. Hence it is interesting to explore the coordinating capabilities of these ligands whether in neutral form or anionic form and to study the structural variations occurring in the ligands during complexation such as change in conformation.

Studies on the nutrient chemistry of a tropical estuary

The study focuses attention on the nutrient chemistry of a tropical estuary namely the cochin estuary.The investigation was planned with the objective of studying the estuarine nutrient behaviour and to assess the role of biogeochemical cycling. The distribution of parameters of interest are better explained in the light of the hydrography of the region . Largely associated with the pollution problems of Cochin estuary receiving industrial and domestic wastes, this thesis projects the role of environmental parameters modifying the nutrient content of the water body coupled with studies on their minute variability subjected to physical, chemical and biological processes. The study has incorporated parameters like temperature, salinity, pH and D0; nutrients were investigated by the study of nitrite, nitrate. ammonia, inorganic reactive phosphorus, dissolved organic phosphorus, particulate reactive phosphorus, total reactive phosphorus and inorganic reactive silicate-silicon at surface and bottom layers of the estuary. Sediment associated interstitial and adsorbed phosphorus for a period of one year (1985-1986] were also incorporated

Nutritional Requirements Of The Fry Of Gold-Spot Mullet Liza Parsa (Hamilton)

Most tropical aquatic environments are naturally fertile and their natural fertility is renewed very rapidly. Natural food for many cultivable organisms can be grown to the maximum by proper management. However, enrichment of the environment can be done through rational fertilization. Still further increase in stocking rates, can yield increased crop if adequate feeding is done. Thus fish and shellfish nutrition is an important aspect of the multidisciplinary subject of aquaculture. The oldest and most classical studies in physiology have investigated the nutritional needs of the species of interest to aquaculture. The alimentary requirements for proteins, lipids, mineral salts and vitamins have been established for some temperate species. But, the nutritional requirements of only few tropical species have been studied. Before formulating a diet, a thorough knowledge of the nutrient requirement of the species is essential. It is against this background that the present area of investigation has been identified. "Nutritional requirements of the fry of gold-spot mullet Liza parsia" is a comprehensive attempt to quantify the nutritional factors that are essential for producing healthy fingerlings for stocking the farms. Aspects such as the protein and lipid requirements of the fry, the vitamin essentiality, nutritive evaluation of protein and lipid sources suitable for compounding diets were covered in this research project. The ultimate aim has been to evolve practical diets which could be applied in the nursery phase for juvenile production.

Chemistry of molecular and supramolecular structures of vanadium(IV) and dioxygen-bridged V(V) complexes incorporating tridentate hydrazone ligands

Four hydrazone ligands: 2-benzoylpyridine benzoyl hydrazone (HBPB), di-2-pyridyl ketone nicotinoyl hydrazone (HDKN), quinoline-2-carbaldehyde benzoyl hydrazone (HQCB), and quinoline-2-carbaldehyde nicotinoyl hydrazone (HQCN) and four of their complexes with vanadyl salts have been synthesized and characterized. Single crystals of HBPB and complexes [VO(BPB)(l2-O)]2 (1) and [VO(DKN)(l2-O)]2 ½H2O (2) were isolated and characterized by X-ray crystallography. Each of the complexes exhibits a binuclear structure where two vanadium(V) atoms are bridged by two oxygen atoms to form distorted octahedral structures within cis-N2O4 donor sets. In most complexes, the uninegative anions function as tridentate ligands, coordinating through the pyridyl- and azomethine-nitrogen atoms and enolic oxygen whereas in complex [VO(HQCN)(SO4)]SO4 4H2O (4) the ligand is coordinated in the keto form. Complexes [VO(QCB)( OMe)] 1.5H2O (3) and 4 are found to be EPR active and showed well-resolved axial anisotropy with two sets of eight line pattern

A CRITICAL STUDY OF THE I/W-'ll/EA/6'1.-' OF GANDHIJI AND HIS TEACHING ON MODERN HINDI POETRY

Hindi