Molecular structure design concept

The synthesis of new and novel bimetallic alkoxide was carried out by applying a molecular structure design concept based on the choice of a proper metal-oxygen core and its completion with hgands to provide the necessary number of donor atoms and sterical protection around the core simultaneously. The freshly prepared alkoxide is highly soluble in mother alcohol, but the solubility decreases on ageing due to the loss of solvating molecules and air hydrolysis which leads to the formation of hydrated oxides [92-97]. 

Chemistry plays an important role in the fabrications of new functional materials with desired properties from conceptual point of view via tuning of microstructural properties. The synthetic approach of functional Inorganic nanomaterials with their novel properties and with their applications is a powerful driving force for the scientists in materials science. The synthesis of single source precursor was carried out based on molecular structure design concept (MSDC) for the stabilization via transformation into a solid crystalline nanostructure material with improved structural and properties. Single source precursor is a molecular entity which contains all the necessary elements of a final product in a well-defined structural formula [36-42]. It is of three types as shown below ... 

The lock-and-key concepts at present are considered in drug design. Samples of protein targets were isolated and X-ray crystallography discovered their molecular structural design. Molecules are conceived either on the basis of similarities with recognized reference structures or on the basis of their complementarily with the three dimensional (3D) structure of well-known active sites. 

A reactive polymer (RP) is simply a device to alloy different materials by changing their molecular structure inside a compounding machine. True reactive alloying induces an interaction between different phases of an incompatible mixture and assures the stability of the mixture s morphology. The concept is not new. This technology is now capable of producing thousands of new compounds to meet specific design requirements. 

Contemporary s Tithetic chemists know detailed information about molecular structures and use sophisticated computer programs to simulate a s Tithesis before trying it in the laboratory. Nevertheless, designing a chemical synthesis requires creativity and a thorough understanding of molecular structure and reactivity. No matter how complex, every chemical synthesis is built on the principles and concepts of general chemistry. One such principle is that quantitative relationships connect the amounts of materials consumed and the amounts of products formed in a chemical reaction. We can use these relationships to calculate the amounts of materials needed to make a desired amount of product and to analyze the efficiency of a chemical synthesis. The quantitative description of chemical reactions is the focus of Chapter 4. 

Molecular structure and properties are key concepts in drug design, but they may not mean the same to all medicinal chemists, not to mention other researchers involved in drug discovery and development such as biochemists, pharmacologists and toxicologists (see Chapter 2). It is therefore the merit of this book to offer a rationalization of these concepts with a view to advocating their value and clarifying their use. 

Testa, B., Kier, L. B. The concept of molecular structure in structure-activity relationship studies and drug design. Med. Res. Rev. 1991, 11, 35 8. 

The concept of a device can be extended to the molecular level11"41 A molecular-level device can be defined as an assembly of a discrete number of molecular components (that is, a supramolecuiar structure) designed to achieve a specific function. Each molecular component performs a single act, while the entire assembly performs a more complex function, which results from the cooperation of the various molecular components. 

Rational drug design is based on a fundamental concept, namely the assumption that the biological effects produced by a specific chemical compound are largely determined by that compound s molecular structure. That is, the three-dimensional structure of a chemical... 

Molecular-level design of catalytic ensemble structures on surfaces in a controllable manner, based on new chemical concepts and strategies regarding composition or structure, provides a promising opportunity for the development of novel and efficient catalysts active for selective oxidation. Novel strategies and concepts for the creation of active ensemble structures on flat and porous surfaces may emerge from self-assembly and in situ transformation of precursors immobilized on the surfaces, with the aid of in situ characterization by sophisticated physical techniques [1-6]. 

The theory of atoms in molecules192 recovers all the fundamental concepts of chemistry, of atoms and functional groups with characteristic properties, of bonds, of molecular structure and structural stability, and of electron pairs and their role in molecular geometry and reactivity. The atomic principle of stationary action extends the predictions of quantum mechanics to the atomic constituents of all matter, the proper open systems of quantum mechanics. All facets of the theory are predictive and, as a consequence, the theory can be employed in many fields of research at the atomic level, from the design and synthesis of new drugs and catalysts, to the understanding and prediction of the properties of alloys. 

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