Article
Plant Sciences
Zsolt Gulyas, Blanka Moncsek, Kamiran Aron Hamow, Pal Straner, Zoltan Tolnai, Eszter Badics, Norbert Incze, Eva Darko, Valeria Nagy, Andras Perczel, Laszlo Kovacs, Vilmos Soos
Summary: This study characterizes D27-LIKE1 in Arabidopsis and highlights its important physiological and enzymatic functions related to carotenoids. The results show that D27-LIKE1 has multi-substrate specificity and may regulate carotenoid cis pools and the biosynthesis pathways of strigolactones and ABA.
Article
Chemistry, Applied
Jolanta Konieczkowska, Mariola Siwy
Summary: This work investigates the thermal cis-trans isomerization in solid-state for poly(ether imide)s and poly(ester imide)s with azobenzene or azo pyridine moieties. The study explores the relationship between various material aspects such as polyimide structure, molar mass, azo dye content, d-spacing value, polymer film thickness, and thermal cis-trans isomerization. The reversibility of the trans-cis-trans reaction was studied using different irradiation wavelengths. This is the first comprehensive article on solid-state cis-trans isomerization for azo polyimides.
Article
Physics, Fluids & Plasmas
Izabela Sliwa, Pavel Maslennikov, Alex Zakharov
Summary: A molecular model is proposed to describe the effective anchoring energy of a liquid crystal system. The model explains the mechanism behind the anchoring transition caused by structural changes in the photosensitive azobenzene layer.
Article
Chemistry, Multidisciplinary
Michele Tomasini, Jin Zhang, Hui Zhao, Emili Besalu, Laura Falivene, Lucia Caporaso, Michal Szostak, Albert Poater
Summary: The cis-trans isomerization of (thio)amides was investigated using DFT calculations to develop a model that explains the higher preference for the cis conformation. The study suggests a method for selecting alkyl/aryl substituents on the C/N atoms that favor the trans isomer. Multilinear analysis, combined with cross-validation analysis, was used to identify the best fitting parameters for the energy barriers of the cis to trans interconversion and the relative stability between the two isomers. Experimental verification confirmed the synthesis of the best trans candidate with sterically demanding t-butyl substituents, demonstrating the utility of predictive chemistry in bridging organic and computational chemistry.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Organic
Gaetano Angelici, Nicholus Bhattacharjee, Maxime Pypec, Laurent Jouffret, Claude Didierjean, Franck Jolibois, Lionel Perrin, Olivier Roy, Claude Taillefumier
Summary: The synthesis and conformational study of N-substituted beta-alanines with tert-butyl side chains are described in this article. Experimental solution NMR spectroscopy, X-ray crystallography, and molecular modeling were used to investigate the conformational preferences of these compounds. It was found that despite their higher flexibility, they still adopt preferred secondary structures including helical and ribbon-like conformations.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Zhao Gao, Fei Yan, Lulu Shi, Yifei Han, Shuai Qiu, Juan Zhang, Feng Wang, Si Wu, Wei Tian
Summary: Photoisomeric supramolecular assemblies have been a hot topic in recent years. In general, the photoisomerization process from irregular aggregates to regular assemblies leads to the destruction of assemblies. However, through the conversion from planar to nonplanar photoisomer, a converse sol-to-gel transition has been achieved. A well-designed acylhydrazone-linked monomer, with imine for trans-cis interconversion and amide for intermolecular hydrogen bonding, is used to drive the photoisomerization-induced self-assembly. The counterintuitive sol-to-gel transition is attributed to the partial trans->cis photoisomerization of acylhydrazone, which changes the stacking mode of monomers. This reversible phase transition also holds potential for miniature materials, as demonstrated in the formation of in situ valves in microfluidic devices.
Article
Chemistry, Multidisciplinary
Sudip Sau, Prasenjit Mal
Summary: The study presents a metal-free one-pot synthesis of 3-nitro-coumarins from aryl alkynoates using tert-butyl nitrite as the sole reagent. The reaction proceeds via radical triggered cyclization and nitration using a cascaded mechanism, showing high efficiency and environmental friendliness.
CHEMICAL COMMUNICATIONS
(2021)
Article
Biochemistry & Molecular Biology
Huan-Hua Xu, Liang Yang, Ming-Xia Tang, An-Ping Ye, Bo-Dan Tu, Zhen-Hong Jiang, Jian-Feng Yi
Summary: This study found that the degree of isomerization of lobeline has a significant impact on its respiratory excitatory effects. The respiratory excitatory effect was significantly reduced with the administration of trans-lobeline injections compared to cis-lobeline injections. The study also discovered that isomerization is a one-way reaction catalyzed by temperature, with pH as the key factor. Lobeline, as a nonselective antagonist with high affinity for nicotinic acetylcholine receptors, has shown potential in the treatment of addiction and nervous system disorders.
Article
Chemistry, Physical
Taposi Chatterjee, Ersad Hossain, Samim Khan, Sourav Roy, Saikh Mohammad Wabaidur, Md Ataul Islam, Seikh Mafiz Alam, Mohammad Hedayetullah Mir
Summary: A Zn(II) based two-dimensional metal-organic framework (MOF) 1 has been synthesized by a slow diffusion method. Compound 1 exhibits photoluminescence property and undergoes in situ cis,cis- to cis,trans-isomerization under visible light. Non-covalent interactions within compound 1 have been investigated using Hirshfeld surface analysis.
JOURNAL OF MOLECULAR STRUCTURE
(2023)
Article
Polymer Science
Zonghao Hong, Lukun Feng, Hiroshi Watanabe, Quan Chen, Hongxia Guo
Summary: The dynamic asymmetry between polyisoprene (PI3) and poly(4-tert-butyl)styrene (PtBS27) in a blend significantly affects its viscoelastic and dielectric properties. At low temperatures, PI3 showed a broad dielectric loss peak with a terminal relaxation frequency close to PtBS27, but this peak narrowed at higher temperatures. Molecular dynamics simulations confirmed the importance of dynamic concentration heterogeneity in PtBS27 for the relaxation of PI3.
Article
Chemistry, Multidisciplinary
Xia Yu, Yuzhang Meng, Hao Zhang, Junbo Guo, Shixian Wang, Hui Li, Jun Hu, Min-Hui Li
Summary: This study synthesized and characterized two pure stereoisomers, trans- and cis-TPE-2GA, which exhibited different aggregation-induced emission, self-assembly properties, and crystallinity. The cis-TPE-2GA showed mechano-chromic properties and a lower energy gap, higher quantum yield, and longer lifetime compared to trans-TPE-2GA, explaining their differences in fluorescence and mechano-chromic properties.
Article
Chemistry, Multidisciplinary
Leijing Chen, Zhen Wang, Hui Liu, Xinyue Li, Bin Wang
Summary: A metal-free radical cyclization/dehydrogenation cascade of alkenes with aldehydes has been developed for the synthesis of 3,5-disubstituted isoxazoles in a one-pot system. This protocol features excellent functional group tolerance and operational simplicity, and is easily scaled up.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Isabella C. D. Merritt, Denis Jacquemin, Morgane Vacher
Summary: This study revisits the cis -> trans photo-isomerisation mechanism of azobenzene using high-level ab initio surface hopping mixed quantum-classical dynamics. Results show a reduction of photoisomerisation quantum yield on exciting to the higher energy pi pi* state compared to the lower energy n pi* state. The explanation for the decrease in quantum yield is found to be different from that observed in the trans -> cis photoisomerisation scenario.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Biochemistry & Molecular Biology
Kritika Kumari, Marina Warepam, Aniket Kumar Bansal, Tanveer Ali Dar, Vladimir N. Uversky, Laishram Rajendrakumar Singh
Summary: TMAO is a significant metabolite derived from various organic compounds, with diverse biological functions in humans. Studies have shown its crucial impact on protein folding and cell cycle, potentially leading to protein misfolding and the development of related diseases.
CELLULAR AND MOLECULAR LIFE SCIENCES
(2022)
Article
Food Science & Technology
Chongyun He, Likang Qin, Jianmei Yang, Yong Zhu
Summary: The regularity of cis-trans isomerization of unsaturated fatty acids in camellia oil under heating was explored through fatty acid profile evolution and reaction kinetics. The temperatures for generating mono-trans linoleic acids and linolelaidic acid were significantly higher than that of elaidic acid. The total trans fatty acids content increased with heating temperature. The study also calculated the activation energy of the cis-trans isomerization reactions, which provides valuable information for inhibiting trans fatty acid formation during camellia oil processing.
LWT-FOOD SCIENCE AND TECHNOLOGY
(2023)
Article
Multidisciplinary Sciences
Clemens Woywod, Franz X. Gruber, Richard A. Engh, Tor Fla
Article
Chemistry, Multidisciplinary
Dilip Narayanan, Osman A. B. S. M. Gani, Franz X. E. Gruber, Richard A. Engh
JOURNAL OF CHEMINFORMATICS
(2017)
Article
Chemistry, Multidisciplinary
Balmukund S. Thakkar, Richard A. Engh
Article
Chemistry, Medicinal
Anna Czarna, Jinhua Wang, Diana Zelencova, Yao Liu, Xianming Deng, Hwan Geun Choi, Tinghu Zhang, Wenjun Zhou, Jae Won Chang, Hanne Kildalsen, Ole Morten Seternes, Nathanael S. Gray, Richard A. Engh, Ulli Rothweiler
JOURNAL OF MEDICINAL CHEMISTRY
(2018)
Article
Plant Sciences
Krzysztof Tarnowski, Maria Klimecka, Arkadiusz Ciesielski, Grazyna Goch, Anna Kulik, Halina Fedak, Jaroslaw Poznanski, Malgorzata Lichocka, Marcin Pierechod, Richard A. Engh, Michal Dadlez, Grazyna Dobrowolska, Maria Bucholc
Correction
Chemistry, Multidisciplinary
Birgit S. Lauber, Leo A. Hardegger, Alam K. Asraful, Bjarte A. Lund, Oliver Dumele, Michael Harder, Bernd Kuhn, Richard A. Engh, Francois Diederich
CHEMISTRY-A EUROPEAN JOURNAL
(2020)
Article
Biochemistry & Molecular Biology
Kazi A. Alam, Osman A. S. B. M. Gani, Richard A. Engh
Summary: The conserved GxGxxG motif in protein kinases plays a crucial role in the binding of inhibitors, with different mutants showing varied binding strengths. Surprisingly, the pan-kinome inhibitor staurosporine exhibits strengthened binding in mutants due to increased binding rates.
JOURNAL OF MOLECULAR RECOGNITION
(2021)
Article
Biochemistry & Molecular Biology
Robin Lorenz, Jian Wu, Friedrich W. Herberg, Susan S. Taylor, Richard A. Engh
Summary: In 1984, Japanese researchers developed the first synthetic protein kinase inhibitors, leading to the approval of the inhibitor fasudil for medical use. These inhibitors competed against endogenous ATP, establishing the druggability of the ATP binding site. Since then, over 70 kinase inhibitors have been approved for clinical use, introducing new paradigms of data driven drug discovery.
Article
Chemistry, Medicinal
Wenche Stensen, Ulli Rothweiler, Richard Alan Engh, Melissa R. Stasko, Ilya Bederman, Alberto C. S. Costa, Anders Fugelli, John S. Mjoen Svendsen
Summary: Down syndrome is a complex genetic disorder with substantial physical, cognitive, and behavioral challenges. While treatment options for physical co-morbidities have improved, cognitive deficits in individuals with DS cannot be addressed pharmacologically, and all individuals with DS develop early onset Alzheimer's disease pathology by the age of 40. The study introduces a novel inhibitor for the protein kinase DYRK1A, which is a key controlling kinase associated with DS.
Article
Chemistry, Physical
Balmukund S. Thakkar, John-Sigurd M. Svendsen, Richard A. Engh
JOURNAL OF PHYSICAL CHEMISTRY A
(2017)
Article
Biochemistry & Molecular Biology
Balmukund Sureshkumar Thakkar, Marte Albrigtsen, John Sigurd Svendsen, Jeanette H. Andersen, Richard Alan Engh
CHEMICAL BIOLOGY & DRUG DESIGN
(2017)