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81.
This publication describes processes for the selection of chemical compounds for the building of a high-throughput screening (HTS) collection for drug discovery, using the currently implemented process in the Discovery Technologies Unit of the Novartis Institute for Biomedical Research, Basel Switzerland as reference. More generally, the currently existing compound acquisition models and practices are discussed. Our informatics, chemistry and biology-driven compound selection consists of two steps: 1) The individual compounds are filtered and grouped into three priority classes on the basis of their individual structural properties. Substructure filters are used to eliminate or penalize compounds based on unwanted structural properties. The similarity of the structures to reference ligands of the main proven druggable target families is computed, and drug-similar compounds are prioritized for the following diversity analysis. 2) The compounds are compared to the archive compounds and a diversity analysis is performed. This is done separately for the prioritized, regular and penalized compounds with increasingly stringent dissimilarity criterion. The process includes collecting vendor catalogues and monitoring the availability of samples together with the selection and purchase decision points. The development of a corporate vendor catalogue database is described. In addition to the selection methods on a per single molecule basis, selection criteria for scaffold and combinatorial chemistry projects in collaboration with compound vendors are discussed.  相似文献   
82.
In the study of the Fe1–xCrxMo1·5O6 system by X-ray, IR and Mössbauer methods the formation of solid state substitution solutions has been detected, which possess similar catalytic properties in methanol oxidation.
, , Fe1–xMo1·5O6 , .
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83.
In the interaction of benzimidazole-2-thione with 1, 2, 3-tribromopropane under conditions of interfacial catalysis in an alkaline medium, 2-(2-bromo-2-propenylthio)benzimidazole is formed; debromination of this compound affords 3-methylthiazolo[3,2-a]benzimidazole, which is subsequently converted as a result of thermolysis to 2-propadienylthio)benzimidazole.For communication 10, see [1].Rostov State University, Rostov-on-Dan 344090. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 567–570, April, 1995. Original article submitted March 11, 1995.  相似文献   
84.
The static modulus of elasticity (E) and the correlation time of rotation ( c ) of 2,-2,6,6-tetramethylpiperidine-1-oxyl are studied as a function of the temperature (210<T <350°K) for oriented films of isotactic polypropylene and polyethylene of high and low density.E and c change both upon heating and polymer orientation; this result indicates that sample properties are influenced by the microstructure of the amorphous phase where probes are localized.  相似文献   
85.
Stresses in secondary glide systems are taken into account in calculations of the strength of dislocation combinations in an fcc crystal with deformation axis oriented in [010], [¯111], and [¯10¯1] directions. The coefficient characterizing the contribution of the reacting component of the dislocation forest to the yield stress is studied as a function of the dislocation densityp.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 11, pp. 48–54, November, 1978.  相似文献   
86.
4,4-Difluoro-5-trifluoromethyl-2-(2,2,2-trifluoro-1-trifluoromethylethyl)-4H-1,3-dioxine andcis/trans-3-dimethylamino-2-trifluoromethacryloyl fluoride were obtained by reaction ofN-(3,3,3-trifluoro-2-trifluoromethylprop-1-enyl)dimethylamine with MgSO4·7H2O. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1069–1071, May, 1997.  相似文献   
87.
The work is devoted to luminescent properties of trivalent lanthanide complexes dispersed in thermoplastic host matrices. Polyethylene films and polypropylene‐rods, both doped with these complexes, were manufactured using an extrusion technique. Two kinds of dopants were used: Eu(III)‐thenoyltrifluoroacetone‐1,10‐phenanthroline complex (1) and Eu(III)‐La(III)‐1,10‐phenanthroline complex (2). Absorption, excitation, emission spectra and lifetime of luminescence were studied. The impact of the polymer matrix on the emission spectra was investigated. Emission spectra of the films were studied at room and helium temperatures. Time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS) surface mapping showed that in the Eu(III)‐La(III) complex europium forms islands (clusters) with a dimension of 1 µm, whereas lanthanum was dispersed more uniformly in the polymer matrix. Dependence of emission intensity on the excitation was determined. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
88.
Methyl 3-[(3,5-dimethylpyrazole-1-carbothioyl)-amino]propionate (L1) and the optically active derivative of natural monoterpene (+)-3-carene, (3bS,4aR)-3-[(3,4,4-trimethyl-3b,4,4a,5-tetrahydro-cyclopropa[3,4]cyclopenta[1,2-c]pyrazole-1-carbothioyl)-amino]propionate (L2), are synthesized. The paramagnetic CuL1Cl2 (I) and [Cu2L2 2Cl4] (II) complexes are obtained. According to the X-ray diffraction data, in mononuclear complex I, the L1 molecule performs a bidentate-cyclic function due to the coordination of the S atom of the C=S group and the N atom of the pyrazole cycle. The CuCl2NS coordination polyhedron is a distorted tetrahedron. Two molecules of complex I form an associate due to weak Cu···S interactions. Compound II is binuclear due to the bridging function of two Cl- ions, and analogous functions of the L1 and L2 ligands. The coordination polyhedron in complex II is CuCl3NS. The eff values for compounds I and II are equal to 1.81 and 1.79 B, respectively, and are constant in the interval from 78 to 300 K, indicating that noticeable exchange interactions between unpaired electrons of the Cu2+ ions are absent. The EPR spectra of the complexes in the solid phase are examined.  相似文献   
89.
Complexation between crown ethers 12C4, 15C5, 18C6 and cryptand 222, and alkali cations Li+, Na+, K+ in various solvents were studied by 17O-NMR. spectroscopy. Small diamagnetic shifts arising from the cation electric field are observed. They increase according to the sequence K+ < Na+ < Li+. 17O-linewidth are discussed and compared to the 13C relaxation times. Linewidth modification results mainly from modifications of the effective correlation time. In general, for crown ethers, considerable line broadening occurs when the cation fits well into the cavity but line narrowing occurs when the cation is much smaller than the cavity.  相似文献   
90.
A method for the calculation of fixed catalyst bed reactors by using a diffusion kinetic model is suggested. Correlation between calculated curves for the time distribution of the reaction mixture composition and experimental data is given.
=qo . .
  相似文献   
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