SSRN Author: Andrey A. ToropovAndrey A. Toropov SSRN Content
http://www.ssrn.com/author=2699730
http://www.ssrn.com/rss/en-usWed, 31 May 2017 01:30:24 GMTeditor@ssrn.com (Editor)Wed, 31 May 2017 01:30:24 GMTwebmaster@ssrn.com (WebMaster)SSRN RSS Generator 1.0New: Calculation of pK Values of Flavylium Salts from the Optimization of Correlation Weights of Local Graph InvariantsA new topological descriptor based on the process of optimization of correlation weights of local graph invariants is proposed to calculate pK values of flavylium salts. Comparison with available experimental data shows a quite satisfactory agreement and present results improved previous calculations resorting to the employment of several molecular and topological descriptors. Some future developments on this issue are pointed out aiming to the use of these models to propose new potential food dyes.
http://www.ssrn.com/abstract=2969511
http://www.ssrn.com/1595189.htmlTue, 30 May 2017 06:28:44 GMTNew: Maximum Topological Distances Based Indices as Molecular Descriptors for QSPR. 3 - Calculation of Hydrophobicity of Polyaromatic HydrocarbonsMaximum topologcial distances based indices are used together with standard ones to compute hydrophobicity of polyaromatic hydrocarbons. Several variables and higher-order regression equations are computed and they show to be excellent predictors for the chosen physical chemistry property. This new alternative seem to be a better way than the usual manner to derive global topological indices for QSPR. Some possible future extensions are pointed out.
http://www.ssrn.com/abstract=2969499
http://www.ssrn.com/1595172.htmlTue, 30 May 2017 06:20:23 GMTNew: Improved Molecular Descriptors to Calculate Boiling Points Based on the Optimization of Correlation Weights of Local Graph InvariantsWe report the calculation of boiling points for several alkyl alcohols through the use of improved molecular descriptors based on the optimization of correlation weights of local invariants of graphs. As local invariants we have used the presence of different chemical chemical elements and the existence of different vertex values. The inherent flexibility of the chosen molecular descriptor seems to be rather suitable to obtain satisfactory predictions of the property under study. Comparison with other similar approximations reveals a very good behaviour of the present method. The use of higher order polynomials do not seem to be necessary to improve the results regarding the simple linear fitting equations. Some possible future extensions are pointed out in order to achieve a more definitive conclusion about this approximation.
http://www.ssrn.com/abstract=2969505
http://www.ssrn.com/1594549.htmlFri, 26 May 2017 12:20:40 GMTNew: Calculation of Total Molecular Electronic Energies from Correlation Weighting of Local Graph InvariantsWe consider correlation weighting of local graph invariants as molecular descriptors for computing total molecular electronic energies. Instead of using prescribed weights for paths and vertices we have optimized such weights so that the correlation coefficient value between descriptors calculated with the correlation weights and total electronic energy values is as large as possible and standard error in regression analysis is as small as possible. Results compare favorably with respect to the employment of other usual rigid topological descriptors.
http://www.ssrn.com/abstract=2969503
http://www.ssrn.com/1594541.htmlFri, 26 May 2017 11:44:13 GMTNew: Improved Molecular Descriptors Based on the Optimization of Correlation Weights of Local Graph InvariantsWe report the calculation of boiling points of several alkyl alcohols through the use of improved molecular descriptors based on the optimization of correlation weights of local graph invariants. As local invariants we have used the presence of different chemical elements and the existence of different vertex degree values. The inherent flexibility of the chosen molecular descriptor seems to be rather suitable to obtain satisfactory enough predictions of the property under study. Comparison with other similar approximations reveals a very good behaviour of the present method.
http://www.ssrn.com/abstract=2969501
http://www.ssrn.com/1594345.htmlFri, 26 May 2017 05:48:00 GMTNew: Improved Qspr Analysis of Standard Entropy of Acyclic and Aromatic Compounds Using Optimized Correlation Weights of Linear Graph InvariantsEntropy is calculated for a representative set of acycliuc and aromatic compounds within the realm of QSAR/QSPR theory. Flexible topological molecular indices are chosen as independent variables in the fitting equations. The comparison wirh results derived from quantum mechanical calculations show that the present approach gives better predictions. Some possible future extensions are pointed out.
http://www.ssrn.com/abstract=2966474
http://www.ssrn.com/1593503.htmlWed, 24 May 2017 07:24:49 GMTNew: Improved Qspr Analysis of Standard Entropy of Acyclic and Aromatic Compounds Using Optimized Correlation Weights of Linear Graph InvariantsEntropy is calculated for a representative set of acycliuc and aromatic compounds within the realm of QSAR/QSPR theory. Flexible topological molecular indices are chosen as independent variables in the fitting equations. The comparison wirh results derived from quantum mechanical calculations show that the present approach gives better predictions. Some possible future extensions are pointed out.
http://www.ssrn.com/abstract=2966474
http://www.ssrn.com/1593502.htmlWed, 24 May 2017 07:24:25 GMTNew: QSAR Carcinogenic Study of Polycyclic Aromatic Hydrocarbons Based on Topological Descriptors Derived from the Detour Matrix and Correlation Weights of Local Graph InvariantsWe present a theoretical calculation of polycyclic atomatic hydrocarbons carcinogenic properties. The calculation method is based on several descriptors derived from the detour matrix and correlatrion weights of local graph invariants. Predicted toxicities agree quite well with available experimental data.
http://www.ssrn.com/abstract=2966468
http://www.ssrn.com/1593492.htmlWed, 24 May 2017 06:40:34 GMTNew: 3d and 4d Molecular Models Derived from the Ideal Symmetry Method. Prediction of Alkanes Normal Boiling PointsThe method of ideal symmetry is applied to define new 3D and 4D molecular descriptors on the basis of some analogies with the vertex distance sum in molecular graphs. These new descriptors are employed together with well known topological descriptors to make up a pool of available variables to perform a multi linear regression analysis of alkanes normal boiling points. Predictions are satisfactory and they compare fairly well with other available theoretical data. The fitting polynomials are improved through the analysis of nonlinear models and in such cases predictions ameliorate, although not in a very spectacular manner. Finally, some possible extensions of the present study are pointed out.
http://www.ssrn.com/abstract=2966467
http://www.ssrn.com/1593490.htmlWed, 24 May 2017 06:35:30 GMT