Computers concordance

In view of latter developments (see Sections 16.4.9-16.4.11 for further details) the procedure, even with simplifications such as using a single CONCORD/ CORINA-derived 3D geometry instead of performing a Monte Carlo conformational search, is too computationally expensive to be applied to e-screening of virtual libraries. However, it may still be a useful alternative/complement for computing more detailed information about a compound, or to provide a more easily interpretable model to complement other models based on more rapidly computable parameters but which are difficult to interpret in terms of how to modify compounds in order for them to have better intestinal absorption characteristics. 

Janzen and Happ generated a series of 2- and 4-acylated pyridine N-oxide radical-anions by the autoxidation of corresponding alkyl or hydroxyalkyl precursors in mixtures of DMSO or DMF with t-butanol containing potassium f-butoxide.355 The computational approach of these workers to the spin distribution problem was rather different from that of the Japanese group,351 but their results and conclusions were essentially concordant. 

Computers have been used as a routine part of pharmacy practice for many years. Pharmacists use this technology in many ways. For example, computers can be used to interact with physician colleagues, track patient behaviors, or as tools to evaluate cost and effectiveness of medication regimens.Pharmacists have also investigated concordance between traditional and computerized patient records, and are now incorporating computers into patient assessment and educational activities. 

Molecular docking and structural alignment methods are based on three-dimensional structures of candidate molecules that can be generated by rule-based methods such as CORINA [13, 14] or CONCORD [15]. However, methods based on three-dimensional structures are computationally quite demanding and cannot routinely be applied to databases of hundreds of thousands of compounds today. For this reason, a number of fast methods to determine molecular similarity have been developed that operate solely on connectivity and atom types of molecules. Such tools allow rapid prescreening of very large databases and avoid a conformational analysis of each candidate molecule. 

For Reaction R4 the rate coefficient Pxx+A computed from Formulae 2.1 and 10 agrees closely with the values found from experiment (usually denoted as a/n or a/p) and long known as the Townsend coefficient of ionization (24). For Reaction R5 and for similar reactions generating the radiative species H2 (a 3V) and N2 (C 3nu), a similar concordance is found between experiment and the predictions of theory (16, 58, 59, 61, 74). In discussing possible interpretations of Kirkby s data for positive column reaction, it is assumed that the Maxwellian form for /(E) is a valid approximation to the true distribution. 

Computation time. CONCORD required extremely short computation times (0.14 sec/molecule), whereas MOLGEO, CONVERTER, and COBRA needed substantially larger times (3.49-8.98 sec/molecule). All other programs needed times of less than 1 sec/molecule. The computation times refer to the number of structures converted by the different programs. 

T o address both the higher computational throughput of nowadays computers and the larger number of experimental 3D structures available now, the above evaluation study was repeated in 2001 using 25,017 x-ray structures. This evaluation was applied to the two now mostly used converters, CONCORD and CORINA. The new dataset... 

A. Rusinko, R. P. Sheridan, R. Nilakantan, K. S. Haraki, N. Bauman, and R. Venkataraghavan,/. Chem. Inf. Comput. Sci., 29,251 (1989). Using CONCORD to Construrt a Large Database of Three-Dimensional Coordinates from Connection Tables. 

M. A. Hendrickson, M. C. Nicklaus, G. W. A. Milne, and D. Zaharevitz, /. Chem. Inf. Comput. Sci., 33, 155 (1993). CONCORD and CAMBRIDGE Comparison of Computer-Generated Chemical Structures with X-ray Crystallographic Data. 

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