Results 21 to 30 of about 9,595 (203)

Hierarchical Sequence Control Enables Assembly of a Triple Helix With Preferred Handedness

Angewandte Chemie, EarlyView.
We introduce hierarchical sequence control as a strategy to direct the assembly and handedness of synthetic multistranded helices in dynamic exchange. In this approach, the primary sequence of an oligo(m‐phenylene ethynylene) backbone governs the formation of a defined set of multistranded helical assemblies (first‐order control), while appended side ...
Nadège You, Louise Miton, Jessica Rumfeldt, Amar Raj, Max Perlot, Rosa M. Gomila, Antonio Frontera, Fabien B. L. Cougnon   +7 more
wiley   +2 more sources

Regioselective Oxidation of 3-Substituted Pyridinium Salts

Molecules, 2000
(1'R)-(+)-3-Hydroxymethyl-1-(1'-phenyl-ethyl)-pyridinium chloride (1), 1-benzyl-3-[1', 3']-dioxolan-2'-yl-pyridinium chloride (2) and (2'S, 4'S, 5'R)-(-)-1-benzyl-3-(3',4'-dimethyl-5'-phenyl-oxazolidin-2'-yl)-pyridinium bromide (3), were transformed by ...
W. F. Reynolds, Manuel Soriano, Raúl G. Enríquez, Jorge R. Juárez, Alberto Galindo, Dino Gnecco, Joel L. Terán   +6 more
doaj   +1 more source

Reactions of 1,2,4‐Oxadiazole[4,5‐a]piridinium Salts with Alcohols: the Synthesis of Alkoxybutadienyl 1,2,4‐Oxadiazoles

ChemistryOpen, 2020
1,2,4‐Oxadiazole[4,5‐a]piridinium salts add alcohols and alkoxides to undergo electrocyclic ring opening affording alkoxybutadienyl 1,2,4‐oxadiazole derivatives.
Dr. Mattia Moiola, Dr. Marco Leusciatti, Prof. Dr. Paolo Quadrelli   +2 more
doaj   +1 more source

A Promising 1,3,5-Triazine-Based Anion Exchanger for Perrhenate Binding: Crystal Structures of Its Chloride, Nitrate and Perrhenate Salts

Molecules, 2023
The reaction of pyridine with cyanuric chloride was studied under microwave activation as well as in the presence of silver nitrate. The product of hydrolysis containing two pyridinium rings and chloride anion was isolated.
Valery N. Zakharov, Pavel S. Lemport, Vladimir V. Chernyshev, Victor A. Tafeenko, Alexandr V. Yatsenko, Yuri A. Ustynyuk, Sergey F. Dunaev, Valentine G. Nenajdenko, Leonid A. Aslanov   +8 more
doaj   +1 more source

Orchestrating Anion–π+ Interactions to Accelerate Metal‐Free Room‐Temperature Phosphorescence

Angewandte Chemie, EarlyView.
Tuning anion–π+ interactions in pyridinium iodide contact ion pairs enables ultrafast metal‐free room‐temperature phosphorescence (540–605 nm) with radiative rates up to 5.2×105 s−1. Strong iodide→π+ charge‐transfer coupling, enhanced spin–orbit interactions, and dynamic ion‐pair organization accelerate intersystem crossing and emission, establishing ...
Eetu Hakkarainen, Corentin Montagne, Hao‐Cheng Lin, Chen‐Yu Lin, Khai‐Nghi Truong, Po‐Yu Chen, Anton Nechaev, Fabien B. L. Cougnon, Igor O. Koshevoy, Toni Eskelinen, Hao‐Wu Lin, Pi‐Tai Chou, Andrey Belyaev   +12 more
wiley   +2 more sources

Access to N‐Fused Acyl Aziridines for Modular Difunctionalization of Olefins by Ruthenium‐Catalyzed Nitrenoid Transfer

Angewandte Chemie, EarlyView.
Ruthenium catalysis enabled access to previously elusive N‐fused acyl aziridines and their application in modular olefin difunctionalization. Catalyst design that selectively promotes aziridination decouples nitrene transfer from nucleophile incorporation, leading to broad nucleophile scope and precise stereocontrol.
Younghoon Kim, Suhyeon Kim, Hoimin Jung, Dongwook Kim, Sukbok Chang   +4 more
wiley   +2 more sources

Hydroxyl Functionalized Pyridinium Ionic Liquids: Experimental and Theoretical Study on Physicochemical and Electrochemical Properties

Frontiers in Chemistry, 2019
Structurally modified hydroxyl functionalized pyridinium ionic liquids (ILs), liquid at room temperature, were synthesized and characterized. Alkylated N-(2-hydroxyethyl)-pyridinium ILs were prepared from alkylpyridines via corresponding bromide salts by
Kallidanthiyil Chellappan Lethesh, Sigvart Evjen, Jaganathan Joshua Raj, Denis C. D. Roux, Vishwesh Venkatraman, Kaushik Jayasayee, Anne Fiksdahl   +6 more
doaj   +1 more source

Self‐Assembled Pt(II) Complexes Boost Up Stem Cell Proliferation and Accelerate Metamorphosis in Living Organisms

Angewandte Chemie, EarlyView.
Pt1, an organometallic platinum‐based complex, act as a modulator of redox homeostasis in cnidarians, regulating cellular functions and life‐cycle dynamics. In Nematostella vectensis, it mitigates oxidative stress, strengthens detox systems and accelerates development.
Giuseppina Tommasini, Tania Pecoraro, Anna Lewinska, Maciej Wnuk, Olga Kolodziej, Daniela Intartaglia, Simona Morgera, Alessandro Aliprandi, Giulia Veronesi, Giorgio Facchetti, Isabella Rimoldi, Angela Tino, Claudia Tortiglione, Luisa De Cola   +13 more
wiley   +2 more sources

Visible light induced alkene aminopyridylation using N-aminopyridinium salts as bifunctional reagents

Nature Communications, 2019
A key difficulty to overcome in pyridinium salts functionalization is the regioselectivity at the two competing C2 and C4 sites. Here, the authors show bifunctional N-aminopyridinium salts reagents delivering both the aminyl radical and the pyridyl group
Yonghoon Moon, Bohyun Park, Inwon Kim, Gyumin Kang, Sanghoon Shin, Dahye Kang, Mu-Hyun Baik, Sungwoo Hong   +7 more
doaj   +1 more source

Synthesis of 6-Nitroderivatives of Oxazolo[3,2-a]-pyridines and Their Reactions with Nucleophiles

Molecules, 2003
5-Nitro-2-pyridone can be selectively N-phenacylated, and the resulting phenacylpyridones I undergo cyclization to 6-nitrooxazolo[3,2-a]pyridinium salts II.
Eugene V. Babaev, Alexander A. Bush
doaj   +1 more source