Results 1 to 10 of about 300,802 (279)

Crown Ether-Peptide Rotaxanes. [PDF]

Angew Chem Int Ed Engl
Abstract We report on the metal‐free active template synthesis of crown ether–peptide rotaxanes. A 24‐crown‐8 ring is sufficiently small that the side chains of canonical branched amino acids act as barriers that trap the macrocycle on the particular glycine residue used to assemble the rotaxane.
Wang PL, Chen P, Yang R, Tetlow DJ, Zhang ZH, Han J, Fielden SDP, Howlader P, Zhang L, Leigh DA.   +9 more
europepmc   +6 more sources

A Theoretical Investigation of the Selectivity of Aza-Crown Ether Structures Chelating Alkali Metal Cations for Potential Biosensing Applications [PDF]

Molecules
Aza-crown ether structures have been proven to be effective in constructing fluorescent biosensors for selectively detecting and imaging alkali metal ions in biological environments. However, choosing the right aza-crown ether for a specific alkali metal
Mouhmad Elayyan, Mark R. Hoffmann, Binglin Sui   +2 more
doaj   +2 more sources

Crown ethers in graphene [PDF]

Nature Communications, 2014
Crown ethers are at their most basic level rings constructed of oxygen atoms linked by two- or three-carbon chains. They have attracted attention for their ability to selectively incorporate various atoms or molecules within the cavity formed by the ring. However, crown ethers are typically highly flexible, frustrating efforts to rigidify them for many
Junjie, Guo, Jaekwang, Lee, Cristian I, Contescu, Nidia C, Gallego, Sokrates T, Pantelides, Stephen J, Pennycook, Bruce A, Moyer, Matthew F, Chisholm   +7 more
openaire   +2 more sources

Inter- and Intra-Molecular Organocatalysis of S_N2 Fluorination by Crown Ether: Kinetics and Quantum Chemical Analysis

Molecules, 2021
We present the intra- and inter-molecular organocatalysis of SN2 fluorination using CsF by crown ether to estimate the efficacy of the promoter and to elucidate the reaction mechanism.
Young-Ho Oh, Wonhyuck Yun, Chul-Hee Kim, Sung-Woo Jang, Sung-Sik Lee, Sungyul Lee, Dong-Wook Kim   +6 more
doaj   +1 more source

New crown-ether Dibenzo-18-crown-4 ligand via sequential one-pot reaction

Results in Chemistry, 2021
A friendly synthetic rout for a new crown-ether was developed in this short communication. The method in question was able to produce the desirable product in high yields (up to 80%), even after some purification steps.
Rodolpho Alessandro Nesta Silva, Sergio Antonio Marques Lima, Pedro Ivo da Silva Maia, Marian Rosaly Davolos, Ana Maria Pires   +4 more
doaj   +1 more source

MOLECULAR MODELLING OF Mn⁺.[DBz16C5] COMPLEXES, M = Li⁺, Na⁺ AND Zn²⁺ BASED ON MNDO/d SEMIEMPIRICAL METHOD

Indonesian Journal of Chemistry, 2010
The effect of substituent on dibenzo-16-crown-5 (DBz16C5) and interaction between these crown ether with metal cations was evaluated using computational chemistry calculations. Substituens where are connected to the benzene ring on the DBz16C5 are -COOH,
Harno Dwi Pranowo, Chairil Anwar
doaj   +1 more source

INTERACTION BETWEEN Li⁺ CATION WITH CROWN ETHERS OF Bz15C5, DBz16C5 AND DBz18C6: MOLECULAR MODELING BASE ON MNDO/d SEMIEMPIRICAL METHOD

Indonesian Journal of Chemistry, 2010
The aim of this research is to find information about the substituent effect to the structure of crown ether benzo-15-crown-5 (Bz15C5), dibenzo-16-crown-5 (DBz16C5) and dibenzo-18-crown-6 (DBz18C6), and also crown ether selectivity to coordinate a Li ...
Harno Dwi Pranowo, Chairil Anwar
doaj   +1 more source

A crown ether supramolecular host-guest complex with Keggin polyoxometalate: Synthesis, crystal structure and electrocatalytic performance for hydrogen evolution reaction

Catalysis Communications, 2022
A new crown ether–polyoxometalate assembly [K(H24C12O6)]3[K(H24C12O6)(CH3CN)][SiMo12O40] (1) based on the Keggin-type polyanion [SiMo12O40]4− was successfully synthesized through one-pot strategy in acetonitrile solution.
Pai Wang, Hongxu Zhang, Peisen Wang, Junjie Zha, Jagadis Gautam, Hanzhi Zhang, Rui Li, Lu-nan Zhang, Guowang Diao, Lubin Ni   +9 more
doaj   +1 more source

Bis(hydroxyammonium) hexachloridoplatinate(IV)–18-crown-6 (1/2)

Acta Crystallographica Section E, 2014
In the title complex, (NH3OH)2[PtCl6]·2C12H24O6, the PtIV atom is coordinated by six chloride anions in a slightly distorted octahedral geometry. The Pt—Cl bond lengths are comparable to those reported for other hexachloridoplatinate(IV) species.
Evgeny Bulatov, Anastasiya Afanasenko, Tatiana Chulkova, Matti Haukka   +3 more
doaj   +1 more source

Achiral Molecular Recognition of Substituted Aniline Position Isomers by Crown Ether Type Chiral Stationary Phase

Molecules, 2021
To understand the selectivity of the crown ether type chiral stationary phase (CSP), the retention selectivity for aniline and the positional isomers of substituted anilines were studied.
Atsushi Ohnishi, Tohru Shibata, Tatsuya Imase, Satoshi Shinkura, Kanji Nagai   +4 more
doaj   +1 more source