Results 31 to 40 of about 156,621 (307)

Palladium-Catalyzed Oxidation of β-C(sp3)-H Bonds of Primary Alkylamines through a Rare Four-Membered Palladacycle Intermediate. [PDF]

, 2020
Site-selective functionalizations of C-H bonds are often achieved with a directing group that leads to five- or six-membered metallacyclic intermediates. Analogous reactions that occur through four-membered metallacycles are rare. We report a challenging
Bunescu, Ala, Ernst, Martin, Hartwig, John F, Qiu, Yehao, Su, Bo, Zuend, Stephan J   +5 more
core   +1 more source

Structural factors controlling the transition between columnar hexagonal and helical mesophase in triphenylene liquid crystals. [PDF]

, 2001
A series of novel triphenylenes has been synthesised by a combination of palladium catalysed coupling, oxidative cyclisation, bromination and nucleophilic aromatic substitution.
Cammidge, Andrew N, Gopee, Hemant
core   +1 more source

Chemical, Spectral, Biological, and Toxicological Studies of Some Benzene Derivatives Used in Pharmaceuticals: In Silico Approach

Journal of Tropical Pharmacy and Chemistry
The immune system of humans is impacted by many drugs. Chemicals that have a gender-bending impact on boys, were synthesized, their use spread, and as a consequence, they entered the ecology, the food chain, and eventually ended up in blood or human ...
Emranul Kabir, M R O Khan Noyon, Md Rabiul Alam, Mr. Nasiruddin, Sajia Islam, Mahima Akter, Monir Uzzaman   +6 more
doaj   +1 more source

Synthesis and Characterization of New 2-Quinolone Sulfonamide Derivatives

مجلة بغداد للعلوم, 2016
A series of new 2-quinolone derivatives linked to benzene sulphonyl moieties were performed by many steps: the first step involved preparation of different coumarins (A1,A2) by condensation of different substituted phenols with ethyl acetoacetate.
Baghdad Science Journal
doaj   +1 more source

Characterization of aromaticity in analogues of titan's atmospheric aerosols with two-step laser desorption ionization mass spectrometry

, 2016
The role of polycyclic aromatic hydrocarbons (PAH) and Nitrogen containing PAH (PANH) as intermediates of aerosol production in the atmosphere of Titan has been a subject of controversy for a long time.
Benilan, Yves, Carrasco, Nathalie, Cernogora, Guy, Gazeau, Marie-Claire, Mahjoub, Ahmed, Schwell, Martin, Szopa, Cyril   +6 more
core   +3 more sources

Structural diversification of pillar[n]arene macrocycles [PDF]

, 2020
Despite the fact that pillar[n]arenes receive major interest as building blocks for supramolecular chemistry and advanced materials, their functionalization is generally limited to the modification of the hydroxy or alkoxy units present on the rims. This
Hoogenboom, Richard, Jerca, Valentin-Victor, Xu, Xiaowen   +2 more
core   +2 more sources

Empirical LCAO parameters for $\pi$ molecular orbitals in planar organic molecules

, 2008
We present a parametrization within a simplified LCAO model (a type of Hueckel model) for the description of $\pi$ molecular orbitals in organic molecules containing $\pi$-bonds between carbon, nitrogen, or oxygen atoms with $sp^2$ hybridization, which ...
Hawke, Laurence, Kalosakas, George, Simserides, Constantinos   +2 more
core   +3 more sources

Structural insights into an engineered feruloyl esterase with improved MHET degrading properties

FEBS Letters, EarlyView.
A feruloyl esterase was engineered to mimic key features of MHETase, enhancing the degradation of PET oligomers. Structural and computational analysis reveal how a point mutation stabilizes the active site and reshapes the binding cleft, expading substrate scope.
Panagiota Karampa, Konstantinos Makryniotis, Theofani‐Iosifina Sousani, Evangelos Topakas, Vangelis Daskalakis, Maria Dimarogona   +5 more
wiley   +1 more source

Design of Jacob’s ladder-based teaching aids for illustrating the dualities of benzene derivatives

Chemistry Teacher International
The dualities of benzene derivatives often make basic organic chemistry challenging for students. This includes the relationship between full structural and line-angle formulas, the distinctions between preferred and systematic IUPAC names for benzene ...
Horikoshi Ryo, Nakajima Hiroki
doaj   +1 more source

A methionine‐lined active site governs carbocation stabilization and product specificity in a bacterial terpene synthase

FEBS Letters, EarlyView.
This study reveals a unique active site enriched in methionine residues and demonstrates that these residues play a critical role by stabilizing carbocation intermediates through novel sulfur–cation interactions. Structure‐guided mutagenesis further revealed variants with significantly altered product profiles, enhancing pseudopterosin formation. These
Marion Ringel, Carl P. O. Helmer, Shani Zev, Ronja Driller, Emily Buhr, Markus Reinbold, Renana Schwartz, Gabriel Foley, Mikael Boden, Daniel Garbe, Gerhard Schenk, Dan Thomas Major, Bernhard Loll, Thomas Brück   +13 more
wiley   +1 more source