Results 21 to 30 of about 12,581 (214)
Beilstein Journal of Organic Chemistry, 2010 A new and facile synthesis of 2-thioxoquinazolin-4-ones by introducing a benzenoid system in the pyrimidine moiety by reacting ethoxymethylene derivatives of 1,3-diarylthiobarbituric acids (DTBA) with active methylene compounds, such as malononitrile and
Nimalini D. Moirangthem +1 more
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The Wiener polarity index of benzenoid systems and nanotubes [PDF]
, 2017 In this paper, we consider a molecular descriptor called the Wiener polarity index, which is defined as the number of unordered pairs of vertices at distance three in a graph.
Tratnik, Niko
core +3 more sources
Valency-Based Topological Properties of Linear Hexagonal Chain and Hammer-Like Benzenoid
Complexity, 2021 Topological indices are quantitative measurements that describe a molecule’s topology and are quantified from the molecule’s graphical representation. The significance of topological indices is linked to their use in QSPR/QSAR modelling as descriptors ...
Yi-Xia Li +4 more
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Iterative Synthesis of Pentacene Derivatives with Continuous Boron–Oxygen Bonds
Angewandte Chemie, EarlyView.An iterative synthetic strategy enables the controlled introduction of continuous multiple B–O bonds at the zigzag edge of acenes. A simple two‐step cycle—ipso iodination and Suzuki cross‐coupling/condensation—efficiently constructs BO‐acenes ranging from naphthalene to pentacene.
Seonghwa Jeong +8 more
wiley +2 more sources
On Computation and Analysis of Topological Index-Based Invariants for Complex Coronoid Systems
Complexity, 2021 In chemical graph theory, benzenoid systems are interrogated as they exhibit the chemical compounds known as benzenoid hydrocarbons. Benzenoid schemes are circumscribed as planar connected finite graphs having no cut vertices wherein the entire internal ...
Muhammad Aamer Rashid +3 more
doaj +1 more source
Journal of Chemistry, 2023 The molecular topology and the chemical structures which are not regular perform a dominant character in designing the compound in connection with their physical and chemical properties.
Maria Singaraj Rosary +3 more
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The Multivariable Zhang–Zhang Polynomial of Phenylenes
Axioms, 2023 The Zhang–Zhang polynomial of a benzenoid system is a well-known counting polynomial that was introduced in 1996. It was designed to enumerate Clar covers, which are spanning subgraphs with only hexagons and edges as connected components.
Niko Tratnik
doaj +1 more source
Analysis of Zigzag and Rhombic Benzenoid Systems via Irregularity Indices
Journal of Mathematics, 2023 Topological indices are numerical quantities associated with the molecular graph of a chemical structure. These indices are used to predict various properties of chemical structures.
Muhammad Awais +3 more
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Degrees of projections of rank loci [PDF]
, 2014 We provide formulas for the degrees of the projections of the locus of square matrices with given rank from linear spaces spanned by a choice of matrix entries.
Aluffi, Paolo
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M-Polynomials And Topological Indices Of Zigzag And Rhombic Benzenoid Systems
Open Chemistry, 2018 M-polynomial of different molecular structures helps to calculate many topological indices. This polynomial is a new idea and its beauty is the wealth of information it contains about the closed forms of degree-based topological indices of molecular ...
Ali Ashaq +3 more
doaj +1 more source