Results 101 to 110 of about 31,425 (239)
The Asymmetric Index of a Graph [PDF]
arXiv, 2018 A graph $G$ is asymmetric if its automorphism group of vertices is trivial. Asymmetric graphs were introduced by Erd\H{o}s and R\'{e}nyi in 1963 where they measured the degree of asymmetry of an asymmetric graph. They proved that any asymmetric graph can be made non-asymmetric by removing some number $r$ of edges and/or adding adding some number $s$ of
arxiv
Subadditive retractions on cones and asymmetric vector norms [PDF]
arXiv, 2020 Asymmetric vector norms are generalizations of asymmetric norms, where the subadditivity inequality is understood in ordered vector space sense. This relation imposes strong conditions on the ordering itself. This note studies on these conditions in the general case, and in the case when the asymmetric vector norm is the metric projection onto the cone
arxiv
ChemSusChem, Accepted Article.Enantiopure β‐chlorohydrins are valuable intermediates in organic synthesis, acting as chiral building blocks for obtaining biologically active compounds. This work presents a one‐pot two‐step linear sequence for the efficient deracemization of β‐chlorohydrins by combining a photocatalytic alcohol oxidation with a stereoselective carbonyl bioreduction ...
Sara Filgueira +3 more
wiley +1 more source
Asymmetric catalysis in synthetic strategies for chiral benzothiazepines
Green Synthesis and Catalysis, 2020 Chiral benzothiazepines constitute the core structures of many foremost pharmaceuticals with diverse biological activities endowed by their unique scaffolds, which poses a great challenge to organic chemists and pharmaceutical researchers.
Haifeng Wang +4 more
doaj
Asymmetric reactions of N-heterocyclic carbene (NHC)-based chiral acyl azoliums and azolium enolates
Green Synthesis and Catalysis, 2021 N-Heterocyclic carbene (NHC) organocatalysis has been recognized as a powerful synthetic strategy for the construction of a wide variety of medicinally and biologically important molecules.
Changgui Zhao +2 more
doaj
European Journal of Inorganic Chemistry, EarlyView.This study investigates the water solution‐derived structure of three zinc(II) based coordination polymers with 3‐(1H‐imidazol‐1‐yl)propanoate ligands by single crystal and powder X‐ray diffraction, infrared spectroscopy supported by theoretical calculations, and thermogravimetry.
Katharina Kodolitsch +5 more
wiley +1 more source
The Use of N-iPr-2,2'-bipyrrolidine Derivatives as Organocatalysts for Asymmetric Michael Additions
CHIMIA, 2006 The recent rapid growth of organocatalysis has shown a new approach in organic chemistry and presents the obvious advantage in the avoidance of expensive and often toxic metals.
Sarah Mossé +2 more
doaj +1 more source
Thiosemicarbazone organocatalysis:Tetrahydropyranylation and 2-deoxygalactosylation reactions and kinetics-based mechanistic investigation [PDF]
, 2017 Thiosemicarbazones are introduced as a new class of highly tunable and efficient organocatalysts. We showcase this by studies of the tetrahydropyranylation reaction, where insights to the mechanism was achieved by a double Hammett analysis of both the ...
Akselsen, Olivia M. +4 more
core +2 more sources
Asymmetric Quantum Cyclic Codes [PDF]
arXiv, 2009 It is recently conjectured in quantum information processing that phase-shift errors occur with high probability than qubit-flip errors, hence the former is more disturbing to quantum information than the later one. This leads us to construct asymmetric quantum error controlling codes to protect quantum information over asymmetric channels, $\Pr Z \geq
arxiv
The Dihydroindeno[2,1‐c]fluorene Core: from Syntheses to Properties and Potential Applications
European Journal of Organic Chemistry, Accepted Article.In the last decade, substances possessing the dihydroindeno[2,1‐c]fluorene scaffold showed interesting photo‐physical properties and other potential applications in electronics. The afore‐mentioned compounds belong to the family of five regioisomeric dihydroindenofluorenes, but unlike other ones, they possess angular or, in the case of higher congeners,
Timothée Cadart, Martin Kotora
wiley +1 more source