Generate structures

In this chapter are set out the most important of the trivial names in current use, and the several systems that generate structure-based names. The emphasis is on parent... 

VI Gillet, P Willett, I Bradshaw. The effectiveness of reactant pools for generating structurally-diverse combinatorial libraries. I Chem Inf Comput Sci 37 731-740, 1997. 

Mesh generation features. Structured mesh, interactive mesh generation. Structured mesh. Structured mesh multiblock. Unstructured mesh, multiblock interface to PATRAN and IDEAS. Unstructured. 

The reason for the efficient epoxidation of explicitly allylic alcohols with this system can be found in the strong associative interactions occurring between the substrate and the catalyst. The [Ti(tartrate)(OR)2]2 dimer 1, which is considered to be the active catalyst in the reaction, will generate structure 2 after the addition of... 

The generation, structure, physical and chemical properties of the closely-related sulfone (1) and sulfoxide (2) functional groups have been thoroughly described and discussed in this volume. 

Abstract An overview on the microwave-enhanced synthesis and decoration of the 2(lH)-pyrazinone system is presented. Scaffold decoration using microwave-enhanced transition-metal-catalyzed reactions for generating structural diversity, as well as the conversion of the 2(lH)-pyrazinone skeleton applying Diels-Alder reactions to generate novel heterocyclic moieties are discussed. The transfer of the solution phase to polymer-supported chemistry (SPOS) is also described in detail. 

The ionization techniques most widely used for LC-MS, however, are termed soft ionization in that they produce primarily molecular species with little fragmentation. It is unlikely that the molecular weight alone will allow a structural assignment to be made and it is therefore desirable to be able to generate structural information from such techniques. There are two ways in which this may be done, one of which, the so-called cone-voltage or in-source fragmentation, is associated specifically with the ionization techniques of electiospray and APCl and is discussed later in Section 4.7.4. The other, termed mass spectrometry-mass spectrometry (MS-MS) or tandem mass spectrometry, is applicable to all forms of ionization, provided that appropriate hardware is available, and is described here. 

In this chapter, the main aspects of mass spectrometry that are necessary for the application of LC-MS have been described. In particular, the use of selected-ion monitoring (SIM) for the development of sensitive and specific assays, and the use of MS-MS for generating structural information from species generated by soft ionization techniques, have been highlighted. Some important aspects of both qualitative and quantitative data analysis have been described and the power of using mass profiles to enhance selectivity and sensitivity has been demonstrated. 

In the previous section, the generation and processing of molecular weight data from electrospray spectra have been described. The other great strength of mass spectrometry is its ability to generate structural information from the analyte... 

The solution structure determination of iron-sulfur proteins is feasible in most cases. To achieve this result, it is necessary to have enough structural constraints to make it possible to obtain a family of conformers with similar folding from many randomly generated structures (95). 

For many proteins, it is possible to generate structures of protein-ligand complexes quite rapidly. It is therefore not uncommon for many hundreds of structures to be determined in support of a drug discovery and optimization project. The major challenge for this level of throughput is informatics support. It is also this type of crystallography that is most in need of semiautomated procedures for structure solution and model building (see Section 12.6). 

Comparison of bond lengths and angles in the generated structures with their default values. 

DipolarCycloaddition Reactions. The 1,3-dipolar cyclization of nitrile oxide with dipolarophiles generates structurally important heterocycles. As shown by Lee,139 the reaction can be carried out in an aqueous-organic biphasic system in which the nitrile oxide substrates can be generated from oximes or hydrazones in situ. The method provides a convenient one-pot procedure for generating a variety of heterocyclic products. 

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