Kirill Blinov

Publications of Kirill Blinov

• Elucidating 'undecipherable' chemical structures using computer-assisted structure elucidation approaches.

  Authors: Mikhail Elyashberg, Kirill Blinov, Sergey Molodtsov, Antony Williams

  Magnetic resonance in chemistry : MRC. 01/2012; 50(1):22-7.

  Structure elucidation using 2D NMR data and application of traditional methods of structure elucidation are known to fail for certain problems. In this work, it is shown that computer-assistedStructure elucidation using 2D NMR data and application of traditional methods of structure elucidation are known to fail for certain problems. In this work, it is shown that computer-assisted structure elucidation methods are capable of solving such problems. We conclude that it is now impossible to evaluate the capabilities of novel NMR experimental techniques in isolation from expert systems developed for processing fuzzy, incomplete and contradictory information obtained from 2D NMR spectra. Copyright © 2012 John Wiley & Sons, Ltd.

• Structural revisions of natural products by Computer-Assisted Structure Elucidation (CASE) systems.

  Authors: Mikhail Elyashberg, Antony J Williams, Kirill Blinov

  Natural product reports. 09/2010; 27(9):1296-328.

• Empirical and DFT GIAO quantum-mechanical methods of (13)C chemical shifts prediction: competitors or collaborators?

  Authors: Mikhail Elyashberg, Kirill Blinov, Yegor Smurnyy, Tatiana Churanova, Antony Williams

  Magnetic resonance in chemistry : MRC. 03/2010; 48(3):219-29.

  The accuracy of (13)C chemical shift prediction by both DFT GIAO quantum-mechanical (QM) and empirical methods was compared using 205 structures for which experimental and QM-calculated chemicalThe accuracy of (13)C chemical shift prediction by both DFT GIAO quantum-mechanical (QM) and empirical methods was compared using 205 structures for which experimental and QM-calculated chemical shifts were published in the literature. For these structures, (13)C chemical shifts were calculated using HOSE code and neural network (NN) algorithms developed within our laboratory. In total, 2531 chemical shifts were analyzed and statistically processed. It has been shown that, in general, QM methods are capable of providing similar but inferior accuracy to the empirical approaches, but quite frequently they give larger mean average error values. For the structural set examined in this work, the following mean absolute errors (MAEs) were found: MAE(HOSE) = 1.58 ppm, MAE(NN) = 1.91 ppm and MAE(QM) = 3.29 ppm. A strategy of combined application of both the empirical and DFT GIAO approaches is suggested. The strategy could provide a synergistic effect if the advantages intrinsic to each method are exploited.

• A systematic approach for the generation and verification of structural hypotheses.

  Authors: Mikhail Elyashberg, Kirill Blinov, Antony Williams

  Magnetic resonance in chemistry : MRC. 02/2009;

  During the process of molecular structure elucidation the selection of the most probable structural hypothesis may be based on chemical shift prediction. The prediction is carried out using eitherDuring the process of molecular structure elucidation the selection of the most probable structural hypothesis may be based on chemical shift prediction. The prediction is carried out using either empirical or quantum-mechanical (QM) methods. When QM methods are used, NMR prediction commonly utilizes the GIAO option of the DFT approximation. In this approach the structural hypotheses are expected to be investigated by scientist. In this article we hope to show that the most rational manner by which to create structural hypotheses is actually by the application of an expert system capable of deducing all potential structures consistent with the experimental spectral data and specifically using 2D NMR data. When an expert system is used the best structure(s) can be distinguished using chemical shift prediction, which is best performed either by an incremental or neural net algorithm. The time-consuming QM calculations can then be applied, if necessary, to one or more of the 'best' structures to confirm the suggested solution. Copyright (c) 2009 John Wiley & Sons, Ltd.

• Computer-assisted methods for molecular structure elucidation: realizing a spectroscopist's dream.

  Authors: Mikhail Elyashberg, Kirill Blinov, Sergey Molodtsov, Yegor Smurnyy, Antony J Williams, Tatiana Churanova

  Journal of cheminformatics. 01/2009; 1:3.

  This article coincides with the 40 year anniversary of the first published works devoted to the creation of algorithms for computer-aided structure elucidation (CASE). The general principles on whichThis article coincides with the 40 year anniversary of the first published works devoted to the creation of algorithms for computer-aided structure elucidation (CASE). The general principles on which CASE methods are based will be reviewed and the present state of the art in this field will be described using, as an example, the expert system Structure Elucidator. The developers of CASE systems have been forced to overcome many obstacles hindering the development of a software application capable of drastically reducing the time and effort required to determine the structures of newly isolated organic compounds. Large complex molecules of up to 100 or more skeletal atoms with topological peculiarity can be quickly identified using the expert system Structure Elucidator based on spectral data. Logical analysis of 2D NMR data frequently allows for the detection of the presence of COSY and HMBC correlations of "nonstandard" length. Fuzzy structure generation provides a possibility to obtain the correct solution even in those cases when an unknown number of nonstandard correlations of unknown length are present in the spectra. The relative stereochemistry of big rigid molecules containing many stereocenters can be determined using the StrucEluc system and NOESY/ROESY 2D NMR data for this purpose. The StrucEluc system continues to be developed in order to expand the general applicability, provide improved workflows, usability of the system and increased reliability of the results. It is expected that expert systems similar to that described in this paper will receive increasing acceptance in the next decade and will ultimately be integrated directly to analytical instruments for the purpose of organic analysis. Work in this direction is in progress. In spite of the fact that many difficulties have already been overcome to deliver on the spectroscopist's dream of "fully automated structure elucidation" there is still work to do. Nevertheless, as the efficiency of expert systems is enhanced the solution of increasingly complex structural problems will be achievable.

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• Applications of 15N NMR spectroscopy in alkaloid chemistry

  Authors: Gary E. Martin, Antony J. Williams, Kirill Blinov, Marina Solntseva

  01/2008: pages 409-471;

• Automated structure elucidation of two unexpected products in a reaction of an alpha,beta-unsaturated pyruvate.

  Authors: Gary J Sharman, Ian C Jones, Mark P Parnell, Michael C Willis, Mary F Mahon, Dean V Carlson, Antony Williams, Mikhail Elyashberg, Kirill Blinov, Sergey G Molodtsov

  Magnetic resonance in chemistry : MRC. 08/2004; 42(7):567-72.

  The reaction between an alpha,beta-unsaturated pyruvate and ethyl diazoacetate (EDA) yielded two unexpected products. The structures of these products were determined by automated elucidation of theThe reaction between an alpha,beta-unsaturated pyruvate and ethyl diazoacetate (EDA) yielded two unexpected products. The structures of these products were determined by automated elucidation of the chemical structures using spectroscopic inputs of a series of 1D and 2D NMR data using the computer program ACD/Structure Elucidator, StrucEluc. The formation of these products is rationalised. Their structures were also confirmed by x-ray crystallography.