A. V. Belik

Theoretical estimation of the possibility of formation of oxadiazocines in the nucleophilic addition of resorcinol to pyrimidines and synthesis of new azoloannelated benzooxadiazocines

A method was proposed for estimating the possibility of cyclization of adducts of resorcinol with pyrimidines to form oxadiazocines based on the conformational criterion and analysis of charges on the C(5) atom of the pyrimidine ring and on the H atom of the hydroxy group of the resulting adducts. A series of new derivatives of 4,5-dihydro-11H-5,11-methanobenzo[g]azolo[1,3,5]oxadiazocines were synthesized.

A Method for Multiconformational Modeling of the Three‐Dimensional Shape of a Molecule

A method for multiconformational modeling of the three‐dimensional shape of a molecule is proposed that includes search for conformers, their optimum superposition, and analysis of spatial features of the resulting structure. The method allows one to determine features of various molecular conformations of compounds under study, to assess the contributions of conformers to particular properties of the substance, to evaluate the space occupied by the molecule, and to compare the average size of the multiconformational model of the molecule with the sizes of the most stable conformations. The potentials of the model are illustrated by density calculations for 137 organic liquids.

Genetic Algorithm for Predicting Structures and Properties of Molecular Aggregates in Organic Substances

A genetic algorithm for predicting the structures and properties of molecular aggregates in organic substances is proposed. It has been used for modeling the most probable dimers and trimers existing in 137 organic liquids. It has been shown that the geometric and energetic features of modeled aggregates agree with known data. The energy of aggregation correlates with the enthalpy of evaporation of substances. The dependence of the energetic and geometric features of aggregates on the chemical nature of their constituent molecules is discussed.

Multiconformational Method for Analyzing the Biological Activity of Molecular Structures

A multiconformational method for analyzing the biological activity of compounds is proposed that combines conformer search algorithms and a 3D‐QSAR receptor modeling procedure. The method allows one to find high‐activity and low‐activity conformers and determine the receptor shape. The biological activity of a substance is determined as a superposition of the activities of its conformers with allowance for their proportions in the substance. Agreement between calculated and experimental conformations and between calculated and experimental biological activities pIC50%) is demonstrated by the example of agonists of the 5‐HT1A receptor.

Evaluating a Degree of Molecular Symmetry and Chirality

A method of evaluating a degree of molecular symmetry is suggested. The symmetry criteria calculated by this technique are useful for predicting phase transition temperatures in mesogen compounds. Methods of evaluating chirality avoiding molecular representation as a set of simplices are proposed. The efficiency of these methods is verified on model structures belonging to different symmetry groups. The new approach may be used to analyze stereochemical relationships between atoms in a molecule.

Algorithm for estimating molecular dissymmetry

A simple criterion for estimating molecular dissymmetry and an algorithm of its calculation are suggested. Calculations are performed for compounds belonging to different point groups. The new molecular characteristic may be used to predict the magnitude and sign of optical rotation.

A new method for predicting conduction anesthesia

A new method for predicting conduction anesthesia has been suggested. The method is based on calculation of theP matrix probabilities of interatomic contacts for each molecule of the compounds considered. TheP matrix enables one to evaluate the main tendencies of atoms and atomic groups to interact in biochemical sorption on the nerve fiber surface. The minimum effective concentrations calculated for 25 compounds are in good agreement with the experimental data. The correlation coefficient between the experimental and calculated values is 0.98 when the standard deviation is 0.1 mmol L−1.