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  • Article
  • Open Access
8 Citations
3,917 Views
14 Pages

New Quinoid Bio-Inspired Materials Using Para-Azaquinodimethane Moiety

  • Walaa Zwaihed,
  • François Maurel,
  • Marwan Kobeissi and
  • Bruno Schmaltz

28 December 2023

Quinoid single molecules are regarded as promising materials for electronic applications due to their tunable chemical structure-driven properties. A series of three single bio-inspired quinoid materials containing para-azaquinodimethane (p-AQM) moie...

  • Review
  • Open Access
5 Citations
2,956 Views
11 Pages

16 November 2023

In recent years, quinoid redox mediators (QRMs) have attracted increasing attention because of their key role in wastewater biotreatment. Previous studies have shown that the anaerobic respiration of many bacteria could be coupled to the reduction an...

  • Communication
  • Open Access
7 Citations
6,541 Views
8 Pages

8 January 2019

Curved (non-planar) aromatic compounds have attracted significant research attention in the fields of basic chemistry and materials science. The contribution of the quinoidal structure in the curved π-conjugated structures has been proposed to be...

  • Article
  • Open Access
7 Citations
2,736 Views
13 Pages

17 December 2022

Solvatochromic dyes are utilized in various chemical and biological media as chemical sensors. Unfortunately, there is no simple way to predict the type of solvatochromism based on the structure of the dye alone, which restricts their design and synt...

  • Article
  • Open Access
8 Citations
4,142 Views
15 Pages

6 July 2020

A series of quinoidal oligothiophenes terminated with carbonyl groups (nTDs, n = 2–4) are studied as p-type organic semiconductors for the active materials in organic field-effect transistors (OFETs) both by the theoretical and experimental app...

  • Review
  • Open Access
16 Citations
4,872 Views
25 Pages

28 September 2022

This review presents literature data: the history of the discovery of quinoid compounds, their biosynthesis and biological activity. Special attention is paid to the description of the quinoid pigments of the sea urchins Scaphechinus mirabilis (from...

  • Article
  • Open Access
1 Citations
3,307 Views
10 Pages

14 April 2022

A vibrational analysis of various poly(o-aminophenol) structures has been undertaken using first principles methods. It is shown that a mixture of quinoid and keto forms of poly(o-aminophenol) gives rise to a simulated spectrum that replicates the ex...

  • Review
  • Open Access
13 Citations
4,130 Views
31 Pages

20 March 2023

This review highlights selected examples, published in the last three to four years, of recent advance in the design, synthesis, properties, and device performance of quinoidal π-conjugated materials. A particular emphasis is placed on emerging ma...

  • Article
  • Open Access
35 Citations
7,549 Views
8 Pages

Capilloquinol: A Novel Farnesyl Quinol from the Dongsha Atoll Soft Coral Sinularia capillosa

  • Shi-Yie Cheng,
  • Ki-Jhih Huang,
  • Shang-Kwei Wang and
  • Chang-Yih Duh

30 August 2011

Capilloquinol (1), possessing an unprecedented farnesyl quinoid skeleton, was isolated from the Dongsha Atoll soft coral Sinularia capillosa. The structure of capilloquinol was elucidated by extensive analysis of spectroscopic data. The cytotoxicity...

  • Article
  • Open Access
4 Citations
10,177 Views
9 Pages

Iminium Salts by Meerwein Alkylation of Ehrlich’s Aldehyde

  • Carmen Froschauer,
  • Hedda K. Weber,
  • Volker Kahlenberg,
  • Gerhard Laus and
  • Herwig Schottenberger

18 March 2013

4-(Dimethylamino)benzaldehyde is alkylated at the N atom by dialkyl sulfates, MeI, or Me3O BF4. In contrast, ethylation by Et3O BF4 occurs selectively at the O atom yielding a quinoid iminium ion. 4-(Diethylamino)benzaldehyde is alkylated only at O b...

  • Article
  • Open Access
6 Citations
3,550 Views
22 Pages

Identification of a Quinone Derivative as a YAP/TEAD Activity Modulator from a Repurposing Library

  • Angela Lauriola,
  • Elisa Uliassi,
  • Matteo Santucci,
  • Maria Laura Bolognesi,
  • Marco Mor,
  • Laura Scalvini,
  • Gian Marco Elisi,
  • Gaia Gozzi,
  • Lorenzo Tagliazucchi and
  • Maria Paola Costi
  • + 4 authors

The transcriptional regulators YAP (Yes-associated protein) and TAZ (transcriptional co-activator with PDZ-binding motif) are the major downstream effectors in the Hippo pathway and are involved in cancer progression through modulation of the activit...

  • Article
  • Open Access
5 Citations
5,775 Views
15 Pages

11 November 2022

We predict the geometries, electronic properties, and aromaticity of thiophene analogues of anti-kekulene with six to nine thiophene rings 14, together with those of cyclobutadithiophenes (CDTs) and anti-kekulene as reference compounds, using...

  • Article
  • Open Access
14 Citations
3,790 Views
13 Pages

Organic–Inorganic Hybrid Pigments Based on Bentonite: Strategies to Stabilize the Quinoidal Base Form of Anthocyanin

  • Robson V. Cunha,
  • Alan I. S. Morais,
  • Pollyana Trigueiro,
  • João Sammy N. de Souza,
  • Dihêgo H. L. Damacena,
  • Luciano C. Brandão-Lima,
  • Roosevelt D. S. Bezerra,
  • Maria Gardennia Fonseca,
  • Edson C. Silva-Filho and
  • Josy A. Osajima

26 January 2023

Anthocyanins are one of the natural pigments that humanity has employed the most and can substitute synthetic food dyes, which are considered toxic. They are responsible for most purple, blue, and red pigment nuances in tubers, fruits, and flowers. H...

  • Article
  • Open Access
2 Citations
3,536 Views
16 Pages

15 April 2022

Quinoidal oligothiophenes have received considerable attention as interesting platforms with remarkable amphoteric redox behavior associated with their diradical character increasing with the conjugation lengths. In this work, we considered a family...

  • Review
  • Open Access
10 Citations
4,689 Views
24 Pages

A Comprehensive Overview of the Developments of Cdc25 Phosphatase Inhibitors

  • Ahmed Bakr Abdelwahab,
  • Eslam Reda El-Sawy,
  • Atef G. Hanna,
  • Denyse Bagrel and
  • Gilbert Kirsch

Cdc25 phosphatases have been considered promising targets for anticancer development due to the correlation of their overexpression with a wide variety of cancers. In the last two decades, the interest in this subject has considerably increased and m...

  • Article
  • Open Access
2 Citations
2,738 Views
15 Pages

The Use of Flavylium Salts as Dynamic Inhibitor Moieties for Human Cb5R

  • Oscar H. Martínez-Costa,
  • Laura Rodrigues-Miranda,
  • Sofia M. Clemente,
  • António Jorge Parola,
  • Nuno Basilio and
  • Alejandro K. Samhan-Arias

23 December 2022

Cytochrome b5 reductase (Cb5R) is a flavoprotein that participates in the reduction of multiple biological redox partners. Co-localization of this protein with nitric oxide sources has been observed in neurons. In addition, the generation of superoxi...

  • Article
  • Open Access
13 Citations
3,595 Views
19 Pages

Synthesis and Evaluation of Antimicrobial and Cytotoxic Activity of Oxathiine-Fused Quinone-Thioglucoside Conjugates of Substituted 1,4-Naphthoquinones

  • Yuri E. Sabutski,
  • Ekaterina S. Menchinskaya,
  • Ludmila S. Shevchenko,
  • Ekaterina A. Chingizova,
  • Artur R. Chingizov,
  • Roman S. Popov,
  • Vladimir A. Denisenko,
  • Valery V. Mikhailov,
  • Dmitry L. Aminin and
  • Sergey G. Polonik

6 August 2020

A series of new tetracyclic oxathiine-fused quinone-thioglycoside conjugates based on biologically active 1,4-naphthoquinones and 1-mercapto derivatives of per-O-acetyl d-glucose, d-galactose, d-xylose, and l-arabinose have been synthesized, characte...

  • Article
  • Open Access
7 Citations
4,032 Views
21 Pages

Experimental and Computational Studies on Bio-Inspired Flavylium Salts as Sensitizers for Dye-Sensitized Solar Cells

  • Iulia Păușescu,
  • Anamaria Todea,
  • Diana-Maria Dreavă,
  • Tania Boboescu,
  • Bianca Pațcan,
  • Larisa Pațcan,
  • Daiana Albulescu,
  • Valentin Badea,
  • Francisc Peter and
  • Mihai Medeleanu
  • + 3 authors

8 October 2022

Six new bio-inspired flavylium salts were synthesized and investigated by a combined computational and experimental study for dye-sensitized solar cell applications. The compounds were characterized by FT–IR, UV–Vis, NMR spectroscopy, and...

  • Article
  • Open Access
1,906 Views
11 Pages

Dual Roles of PTSA in Electrical Conductivity of PEDOT:PTSA with Large Seebeck Coefficient

  • Hideki Arimatsu,
  • Yuki Osada,
  • Ryo Takagi,
  • Yosuke Ohira,
  • Tomoki Hijikata and
  • Takuya Fujima

29 January 2025

The electrical conduction mechanism of PEDOT:PTSA thermoelectric conversion material supported on PET fiber was investigated with varying PTSA concentrations. Raman analysis revealed that an increasing PTSA concentration promoted transformation from...

  • Article
  • Open Access
4 Citations
2,686 Views
10 Pages

Influence of a Constant Magnetic Field on the Mechanism of Adrenaline Oxidation

  • Vyacheslav N. Kazin,
  • Evgenii A. Guzov,
  • Valentina A. Moshareva and
  • Evgenii M. Pliss

In order to establish the role of the magnetic effect in the key stages of the autoxidation and initiated oxidation radical-chain reactions, the experimental data and kinetic analysis of the influence of a magnetic field on the oxidative transformati...

  • Article
  • Open Access
10 Citations
6,654 Views
12 Pages

Oxidation of 2-Hydroxynevirapine, a Phenolic Metabolite of the Anti-HIV Drug Nevirapine: Evidence for an Unusual Pyridine Ring Contraction

  • Alexandra M. M. Antunes,
  • Muna Sidarus,
  • David A. Novais,
  • Shrika G. Harjivan,
  • Pedro P. Santos,
  • João L. Ferreira da Silva,
  • Frederick A. Beland and
  • M. Matilde Marques

5 March 2012

Nevirapine (NVP) is an anti-HIV drug associated with severe hepatotoxicity and skin rashes, which raises concerns about its chronic administration. There is increasing evidence that metabolic activation to reactive electrophiles capable of reacting w...

  • Article
  • Open Access
18 Citations
5,749 Views
10 Pages

26 June 2017

Microorganisms are important sources for screening bioactive natural products. However, natural products from deep-sea microbes have not been extensively explored. In this study, the metabolites of bacteriophage GVE2 -infected (Geobacillus sp. E263 v...

  • Article
  • Open Access
15 Citations
5,418 Views
10 Pages

11 October 2018

In the present paper, methyl gallate (MeG), a simple polyphenol and also the monomer of hydrolysable tannins, was selected to study the deprotonation process for the hydroxyls of the galloyl group by the combined use of spectroscopic measurements and...

  • Article
  • Open Access
3 Citations
3,409 Views
15 Pages

19 November 2021

The use of composite films with semiconductor behavior is an alternative to enhance the efficiency of optoelectronic devices. Composite films of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and metalloporphines (MPs; M = Co, Cu...

  • Article
  • Open Access
7 Citations
4,739 Views
14 Pages

Effects of Intra- and Interchain Interactions on Exciton Dynamics of PTB7 Revealed by Model Oligomers

  • Thomas J. Fauvell,
  • Zhengxu Cai,
  • Matthew S. Kirschner,
  • Waleed Helweh,
  • Pyosang Kim,
  • Tianyue Zheng,
  • Richard D. Schaller,
  • Luping Yu and
  • Lin X. Chen

Recent studies have shown that molecular aggregation structures in precursor solutions of organic photovoltaic (OPV) polymers have substantial influence on polymer film morphology, exciton and charge carrier transport dynamics, and hence, the resulta...

  • Article
  • Open Access
2 Citations
6,994 Views
10 Pages

30 May 2011

Oxidative polycondensation of 3,4-ethylenedioxythiophene and (–)-myrtenal was carried out with POCl3. A p-conjugated system thus constructed consists of aromatic and quinoidal alternating structure linked via methine groups. We examined iodine doping...

  • Article
  • Open Access
4 Citations
3,540 Views
13 Pages

Green Synthesis and Electrochemical Properties of Mono- and Dimers Derived from Phenylaminoisoquinolinequinones

  • Juana Andrea Ibacache,
  • Jaime A. Valderrama,
  • Judith Faúndes,
  • Alex Danimann,
  • Francisco J. Recio and
  • César A. Zúñiga

30 November 2019

In the search for new quinoid compounds endowed with potential anticancer activity, the synthesis of novel heterodimers containing the cytotoxic 7-phenylaminoisoquinolinequinone and 2-phenylaminonaphthoquinone pharmacophores, connected through methyl...

  • Article
  • Open Access
1,172 Views
16 Pages

Reactions of Plasmodium falciparum Type II NADH: Ubiquinone Oxidoreductase with Nonphysiological Quinoidal and Nitroaromatic Oxidants

  • Lina Misevičienė,
  • Marie-Pierre Golinelli-Cohen,
  • Visvaldas Kairys,
  • Audronė Marozienė,
  • Mindaugas Lesanavičius and
  • Narimantas Čėnas

In order to detail the antiplasmodial effects of quinones (Q) and nitroaromatic compounds (ArNO2), we investigated their reduction mechanism by Plasmodium falciparum flavoenzyme type II NADH:ubiquinone oxidoreductase (PfNDH2). The reactivity of Q and...

  • Abstract
  • Open Access
1,301 Views
1 Page

Phytochemical products start to be employed to assist 2D nanomaterials exfoliation. However, a lack of studies regarding the molecules involved and their capacity to give rise to functional materials is evident. In this work, a novel green liquid-pha...

  • Article
  • Open Access
6 Citations
4,275 Views
9 Pages

30 October 2020

We present a method to prepare polyaminophenol from solid-state aminophenol monomers using atmospheric dielectric barrier discharge (DBD) plasma. The polymerizations of o-aminophenol and m-aminophenol are studied. The polymers were analyzed via Fouri...

  • Proceeding Paper
  • Open Access
1,875 Views
6 Pages

14 November 2018

Recently there has been a growing interest in covalent protease inhibitors in both industry and academia, caused by their longer residence times, their higher potency and their high ligand efficiency. Covalently reactive moieties which interact with...

  • Article
  • Open Access
31 Citations
7,814 Views
13 Pages

22 August 2014

Radical scavenging activity of anthocyanins is well known, but only a few studies have been conducted by quantum chemical approach. The adaptive neuro-fuzzy inference system (ANFIS) is an effective technique for solving problems with uncertainty. The...

  • Review
  • Open Access
25 Citations
7,288 Views
23 Pages

7 February 2012

Benzo-condensed four-ring heterocycles, such as benzoxetes 1 and benzothietes 3 represent multi-purpose starting compounds for the preparation of various higher heterocyclic ring systems. The thermal or photochemical valence isomerizations between th...

  • Article
  • Open Access
2 Citations
3,455 Views
17 Pages

Innovative Application of Salophen Derivatives in Organic Electronics as a Composite Film with a Poly(3,4-Ethylenedioxythiophene)-poly(styrenesulfonate) Matrix

  • María Elena Sánchez Vergara,
  • Omar Jimenez Correa,
  • Ricardo Ballinas-Indilí,
  • Ismael Cosme,
  • José Ramón Álvarez Bada and
  • Cecilio Álvarez-Toledano

17 September 2024

In this work, we present the innovative synthesis of salophen (acetaminosalol) derivatives in a solvent-free environment by high-speed ball milling, using a non-conventional activation method, which allowed obtaining compounds in a shorter time and w...

  • Article
  • Open Access
1 Citations
2,386 Views
11 Pages

Sequential Cascade Doping of Conjugated-Polymer-Wrapped Carbon Nanotubes for Highly Electrically Conductive Platforms

  • Da Young Lee,
  • Da Eun Choi,
  • Yejin Ahn,
  • Hyojin Kye,
  • Min Seon Kim and
  • Bong-Gi Kim

1 July 2024

To explore a highly conductive flexible platform, this study develops PIDF-BT@SWCNT by wrapping single-walled carbon nanotubes (SWCNTs) with a conjugated polymer, PIDF-BT, known for its effective doping properties. By evaluating the doping behaviors...

  • Article
  • Open Access
17 Citations
10,272 Views
16 Pages

Synthesis and Properties of Octithiophene Dication Sterically Segregated by Annelation with Bicyclo[2.2.2]octene Units

  • Tohru Nishinaga,
  • Daisuke Yamazaki,
  • Masaki Tateno,
  • Masahiko Iyoda and
  • Koichi Komatsu

19 March 2010

Octithiophene sterically segregated by annelation with bicyclo[2.2.2]octene (BCO) units was synthesized to study the unimolecular properties of longer oligothiophene dications. For the preparation of such longer oligomers, a new route for the synthes...

  • Article
  • Open Access
74 Citations
9,767 Views
25 Pages

10 November 2016

Anthocyanins are identified by the respective flavylium cation, which is only one species of a multistate of different molecules reversibly interconverted by external inputs such as pH, light and temperature. The flavylium cation (acidic form) is inv...

  • Review
  • Open Access
163 Citations
23,537 Views
64 Pages

Anthraquinones and Derivatives from Marine-Derived Fungi: Structural Diversity and Selected Biological Activities

  • Mireille Fouillaud,
  • Mekala Venkatachalam,
  • Emmanuelle Girard-Valenciennes,
  • Yanis Caro and
  • Laurent Dufossé

25 March 2016

Anthraquinones and their derivatives constitute a large group of quinoid compounds with about 700 molecules described. They are widespread in fungi and their chemical diversity and biological activities recently attracted attention of industries in s...

  • Article
  • Open Access
5 Citations
2,530 Views
18 Pages

Halochromic Behavior and Anticancer Effect of New Synthetic Anthocyanidins Complexed with β-Cyclodextrin Derivatives

  • Iulia Păușescu,
  • Izolda Kántor,
  • György Babos,
  • Zoltán May,
  • Andrea Fodor-Kardos,
  • Zsombor Miskolczy,
  • László Biczók,
  • Francisc Péter,
  • Mihai Medeleanu and
  • Tivadar Feczkó

Anthocyanidins, the aglycons of anthocyanins, are known, beyond their function in plants, also as compounds with a wide range of biological and pharmacological activities, including cytostatic effect against various cancer cells. The nature and posit...

  • Article
  • Open Access
2 Citations
2,596 Views
15 Pages

We have studied, by density functional theory, the interaction between luteolin and Ag, devising two complexes where an Ag14 cluster faces two different sites of the molecule. The two sites are identified as quinoid-like and cathecol-like, and the co...

  • Article
  • Open Access
37 Citations
8,996 Views
14 Pages

3 March 2020

A two-step approach of improving the thermoelectric properties of Poly(3,4-ethylenedioxythiophene)poly(4-styrenesulfonate) (PEDOT:PSS) via the addition of the ionic liquid, 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIM:TFSI) and...

  • Feature Paper
  • Review
  • Open Access
120 Citations
14,144 Views
30 Pages

Biocatalysis with Laccases: An Updated Overview

  • Ivan Bassanini,
  • Erica Elisa Ferrandi,
  • Sergio Riva and
  • Daniela Monti

28 December 2020

Laccases are multicopper oxidases, which have been widely investigated in recent decades thanks to their ability to oxidize organic substrates to the corresponding radicals while producing water at the expense of molecular oxygen. Besides their succe...

  • Article
  • Open Access
18 Citations
3,528 Views
15 Pages

13 May 2019

We report the preparation of bifunctional hybrid catalysts by supporting H3PMo12O40 (PMo12) heteropolyacid (HPA) on polyaniline (PAN) or formyl-functionalized PAN (F-PAN) for the “one-pot” and “one-step” synthesis of 2,5-difor...

  • Article
  • Open Access
75 Citations
4,950 Views
12 Pages

13 September 2018

Cryptotanshinone (CTT) is a natural product and a quinoid diterpene isolated from the root of the Asian medicinal plant, Salvia miltiorrhizabunge. Notably, CTT has a variety of anti-cancer actions, including the activation of apoptosis, anti-prolifer...

  • Review
  • Open Access
6 Citations
3,146 Views
17 Pages

Polyhaloaromatic compounds (XAr) are ubiquitous and recalcitrant in the environment. They are potentially carcinogenic to organisms and may induce serious risks to the ecosystem, raising increasing public concern. Therefore, it is important to detect...

  • Article
  • Open Access
2 Citations
3,754 Views
15 Pages

17 February 2023

Photoresponsive molecular devices can be a valuable tool to promote chemical changes in response to multiple signals, such as photons and pH, to deliver drugs or to detect physiological conditions in vivo. For example, trans-chalcones (Ct) from 4&pri...

  • Article
  • Open Access
6 Citations
6,260 Views
20 Pages

The Hydractinia echinata Test-System. III: Structure-Toxicity Relationship Study of Some Azo-, Azo-Anilide, and Diazonium Salt Derivatives

  • Sergiu Adrian Chicu,
  • Melania Munteanu,
  • Ioana Cîtu,
  • Codruta Şoica,
  • Cristina Dehelean,
  • Cristina Trandafirescu,
  • Simona Funar-Timofei,
  • Daniela Ionescu and
  • Georgeta Maria Simu

8 July 2014

Structure-toxicity relationships for a series of 75 azo and azo-anilide dyes and five diazonium salts were developed using Hydractinia echinata (H. echinata) as model species. In addition, based on these relationships, predictions for 58 other azo-d...

  • Article
  • Open Access
5 Citations
3,724 Views
22 Pages

Reaction Mechanisms of H2S Oxidation by Naphthoquinones

  • Kenneth R. Olson,
  • Kasey J. Clear,
  • Tsuyoshi Takata,
  • Yan Gao,
  • Zhilin Ma,
  • Ella Pfaff,
  • Anthony Travlos,
  • Jennifer Luu,
  • Katherine Wilson and
  • Karl D. Straub
  • + 7 authors

1,4-naphthoquinones (NQs) catalytically oxidize H2S to per- and polysufides and sulfoxides, reduce oxygen to superoxide and hydrogen peroxide, and can form NQ-SH adducts through Michael addition. Here, we measured oxygen consumption and used sulfur-s...

  • Article
  • Open Access
1,044 Views
11 Pages

Polyurethane-Based Electronic Packaging: The Characterization of Natural Aging over a Decade

  • Xiaoqin Wei,
  • Han Li,
  • Rui Zhou,
  • Changcheng Xie and
  • Honglong Ning

18 September 2025

Electronic devices with polyurethane electronic packaging have been stored in Chinese tropical marine atmosphere environments for 10 years. The long-term natural aging mechanism was studied by comparing the appearance inspection, molecular structure,...

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