A quantitative structure–property relationship (QSPR) modeling of vapor pressure at 298.15 K, expressed as log (VP / Pa) was performed for a series of 84 hydrocarbons (63 alkanes and 21 cycloalkanes) using the van der Waals (vdW) surface area, SW / Å, calculated by the Monte Carlo method, as the molecular descriptor. The QSPR model developed from the subset of 63 alkanes (C1–C16), deemed as the...

A scheme of a neural device intended for searching direct correlations between structures and properties of organic compounds without preliminary computation of molecular descriptors (that are invariant with respect to renumbering atoms in a molecule) is suggested. The invariance of a property with respect to renumbering atoms in a molecule is ensured by the architecture of the neural device, w...

The spectral graph theory explores connections between combinatorial features of graphs and algebraic properties associated matrices. neighborhood inverse sum indeg (NI) index was recently proposed explored to be a significant molecular descriptor. Our aim is investigate the NI from standpoint, for which suitable matrix proposed. symmetric since it generated edge connection information undirect...

The atom-bond connectivity (ABC) index is a degree-based molecular descriptor, that found chemical applications. It is well known that among all connected graphs, the graphs with minimal ABC index are trees. A complete characterization of trees with minimal ABC index is still an open problem. In this paper, we present new structural properties of trees with minimal ABC index. Our main results r...

In order to explore atomic asymmetry and molecular chirality in 2D space, benzenoids composed of 3 to 11 hexagons in 2D space were enumerated in our laboratory. These benzenoids are regarded as planar connected polyhexes and have no internal holes; that is, their internal regions are filled with hexagons. The produced dataset was composed of 357,968 benzenoids, including more than 14 million at...

Molecular Field Topology Analysis (MFTA) [1] is a QSAR approach based on the local (atomic) descriptors. First, a so-called molecular supergraph is constructed which is a simple graph such that the molecular graphs of all training set structures can be represented as its subgraphs. A uniform descriptor set for the statistical analysis is obtained by superimposing each training set structure ont...

Molecular similarity is a pervasive concept in drug design. The basic idea underlying molecular similarity is the similar property principle, which states that structurally similar molecules will exhibit similar physicochemical and biological properties. In this paper, a new graph-based molecular descriptor (GBMD) is introduced. The GBMD is a new method of obtaining a rough description of 2D mo...

A generally applicable computer algorithm for the calculation of the seven molecular descriptors heat of combustion, logPoctanol/water, logS (water solubility), molar refractivity, molecular polarizability, aqueous toxicity (protozoan growth inhibition) and logBB (log (cblood/cbrain)) is presented. The method, an extendable form of the group-additivity method, is based on the complete break-dow...

The relationships of several key molecular descriptors with the rate of the O'Donnell alkylation under phase transfer catalysis (PTC) have been investigated. Themost common parameter used to predict PTC rates, the ammonium ion accessibility, q, is defined in such a way that limits its use to straight-chain tetraalkylammonium catalysts. To find a general descriptor of rate, eight linear, symmetr...