Article
Chemistry, Multidisciplinary
Louis Monsigny, Anna Kajetanowicz, Karol Grela
Summary: This review discusses a distinct class of ruthenium olefin metathesis catalysts with unsymmetrical N-heterocyclic carbene (uNHC) ligands, highlighting their advantages such as thermodynamic stability, chemical latency, selectivity, and compatibility with green solvents in specialized metathesis transformations. Despite being niche, uNHC complexes have the potential to be implemented in various industrial processes like valorization of Fischer-Tropsch olefin fractions, ethenolysis of renewable products, and modern pharmaceutical production.
Article
Chemistry, Physical
Antonio Del Vecchio, Jakub Talcik, Sophie Colombel-Rouen, Jan Lorkowski, Melinda R. Serrato, Thierry Roisnel, Nicolas Vanthuyne, Guy Bertrand, Rodolphe Jazzar, Marc Mauduit
Summary: New Blechert-type ruthenium complexes with cyclic(alkyl)(amino)carbene (CAAC) ligands show remarkable thermal stability in solution and excellent catalytic performances in various metathesis reactions. They exhibit high catalytic activity at low loading and can achieve high enantiomeric excess in asymmetric metathesis reactions.
Article
Chemistry, Physical
Renat Kadyrov
Summary: An efficient and simple catalytic system has been developed for the hydrogenation of carboxylic esters using commercially available Ru-salts and imidazolium salts. This combination enables the reduction of esters to alcohols at moderate temperature and pressure, offering a practical method for alcohol synthesis.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Physical
Haoyu Wang, Haitao Yu, Dong Bai, Dan Yao, Yongjun Han, Yichao Shi, Zhiqun Wang
Summary: A ruthenium olefin metathesis catalyst (C1-H) with a novel NHC ligand tethered by an ethoxy-pyridyl arm was synthesized and compared with its methylated derivative (C1-Me). The study showed profound variations in initiation rate, kinetics, metathesis activity, and decomposition behavior between these two catalysts. The remote torsional strain was found to have a considerable influence on the catalytic activity and decomposition behavior of this ligand class.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Applied
Eva Pump, Albert Poater, Naeimeh Bahri-Laleh, Raffaele Credendino, Luigi Serra, Vittorio Scarano, Luigi Cavallo
Summary: This study computationally investigates the origin of chemo-, regio- and stereoselectivity in cross metathesis reactions leading to the desired product. By comparing the relative stabilities of intermediates and products, as well as transition states, the probability for each pathway is linked. The transition states in each reaction play a crucial role in tuning the regio- and stereoselectivity by defining the energy barriers needed to form the final product. The research findings provide valuable insights for understanding the selectivity in new olefin metathesis reactions and a web-server is developed to support future predictive catalysis.
Article
Chemistry, Applied
Louis Monsigny, Jakub Piatkowski, Damian Trzybinski, Krzysztof Wozniak, Tomasz Nienaltowski, Anna Kajetanowicz, Karol Grela
Summary: Two new ruthenium complexes, Sil-II and Sil-II', were synthesized and characterized as catalysts for olefin metathesis reactions. Sil-II' showed better stability and productivity compared to Sil-II, and kinetic experiments revealed differences in initiation mechanisms between the two catalysts.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Applied
Augustin Nouaille, Xavier Pannecoucke, Thomas Poisson, Samuel Couve-Bonnaire
Summary: This study presents an efficient ruthenium-catalyzed CM reaction method, successfully allowing various alkenes to react with methyl 2-fluoroacrylate to obtain trisubstituted fluoroalkenes for the first time. Additionally, an unprecedented TON value for the CM reaction involving fluoroalkenes was achieved, demonstrating good tolerance and effectiveness with a wide range of olefin partners.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Inorganic & Nuclear
Javier Ruiz, Maria A. Mateo
Summary: An isocyanide-functionalized imidazole was synthesized from 4-(1H-imidazol-1-yl)aniline using the Ugi method, and subsequently converted into the corresponding imidazolium salt. Coordination of the isocyanide residue allowed the synthesis of several transition metal complexes containing a peripheral imidazolium cation, which serve as suitable starting materials for the formation of mixed ligand isocyanide-NHC heterometallic complexes.
DALTON TRANSACTIONS
(2022)
Article
Chemistry, Multidisciplinary
Bo Yang, Suqiong Yan, Chengbo Li, Hui Ma, Fanda Feng, Yuan Zhang, Wei Huang
Summary: This study presents Mn(III)-mediated C-P bond activation and intramolecular cyclization of diphosphines, generating phosphahelicene cations or phosphoniums with nice regioselectivity and substrate universality. The unusual radical mechanism and electron-deficient character of novel phosphahelicenes were revealed, leading to versatile fluorescence with good tunability and excellent efficiency. Enantiomerically enriched crystals of phosphahelicenes emitted intense circularly polarized luminescence, with racemic phosphahelicenes showing modulated CPL induced by chiral transmission in the cholesteric mesophase.
Article
Chemistry, Physical
Feng Han, Peter H. Choi, Chen-Xi Ye, Yvonne Grell, Xiulan Xie, Sergei I. Ivlev, Shuming Chen, Eric Meggers
Summary: A cyclometalated ruthenium complex with exclusively metal-centered chirality has been developed for the catalytic conversion of diazoketones to chiral flavanones. The reaction exhibits high yields (up to 99%) and high enantioselectivity (up to 96%). The unwanted C-O formation pathway was successfully suppressed in favor of a catalytic enantioselective ring-closing C(sp(3))-H carbene insertion, as supported by density functional theory calculations. This method provides access to a variety of chiral flavanones, which are privileged scaffolds with diverse biological activities.
Article
Chemistry, Multidisciplinary
Valentina Pelliccioli, Thierry Hartung, Martin Simon, Christopher Golz, Emanuela Licandro, Silvia Cauteruccio, Manuel Alcarazo
Summary: The study reports a highly enantioselective synthesis of 5,13-disubstituted dibenzo[d,d']benzo[1,2-b:4,3-b']dithiophenes, with the last two successive Au-catalyzed intra-molecular alkyne hydroarylation events being crucial for the successful assembly of these helical architectures.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Alexander Kravchenko, Brian J. J. Timmer, A. Ken Inge, Maurice Biedermann, Olof Ramstrom
Summary: A series of olefin metathesis catalysts bearing cyclic (alkyl)(amino)carbene (CAAC) ligands of varying size and steric demand have been synthesized and evaluated for their performance in ring-closing, self, and cross-metathesis reactions. These catalysts exhibit high stability and activity, making them potentially valuable in the screening of bioactive compounds.
Article
Chemistry, Inorganic & Nuclear
Lingyu Kong, Yajie Chou, Muriel Albalat, Marion Jean, Nicolas Vanthuyne, Stephane Humbel, Paola Nava, Herve Clavier
Summary: The concept of atropisomeric N-heterocyclic carbene (NHC)-metal complexes with C-2-symmetry was extended to palladium-based complexes. Through a comprehensive study of NHC precursors and screening of various NHC ligands, the formation of meso complexes was successfully circumvented. Eight atropisomeric NHC-palladium complexes were prepared and obtained with high enantiopurities through efficient chiral HPLC resolution. These complexes demonstrated good activity in the intramolecular alpha-arylation of amides, leading to the isolation of cyclic products with excellent enantioselectivities (up to 98% ee).
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Inorganic & Nuclear
Sangeeta Kumari, Charu Sharma, Avinash K. Srivastava, Naveen Satrawala, Kamal N. Sharma, Raj K. Joshi
Summary: A Ru(II) complex was synthesized for C-H bond activation alkenylation of arenes using thioether directing groups, achieving high yields under milder conditions compared to previous methods utilizing precious noble metal catalysts. Broad substrate scope was demonstrated with good tolerance towards benzyl thioethers and vinyl, making it the first report of its kind utilizing a Ru-based catalyst for thioether alkenylation.
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Adrian Sytniczuk, Filip Struzik, Vishal Purohit, Karol Grela, Anna Kajetanowicz
Summary: The synthesis of inexpensive 2-isopropyl-6-methylaniline analogues was achieved through the employment of aza-Claisen rearrangement and subsequent reduction of anilines, overcoming the issue of high price and low availability. The obtained aniline derivatives were utilized in the synthesis of lipophilic Hoveyda-Grubbs-type complexes, serving as efficient catalysts in ethenolysis reactions. The complexes with bulky sec-butyl substituent exhibited superior performance compared to the leading catalyst based on 2-isopropyl-6-methylaniline, making them valuable candidates for large-scale industrial production with a TON of up to 192,000.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Medicinal
Duy Dinh Do Pham, Viktor Mojr, Michaela Helusova, Gabriela Mikusova, Radek Pohl, Eva Davidova, Hana Sanderova, Dragana Vitovska, Katerina Bogdanova, Renata Vecerova, Miroslava Htoutou Sedlakova, Radovan Fiser, Petra Sudzinova, Jiri Pospisil, Oldrich Benada, Tomas Krizek, Adela Galandakova, Milan Kolar, Libor Krasny, Dominik Rejman
Summary: The novel antibacterial compounds LEGO-LPPOs were developed based on LPPOs, showing activity against various bacteria with low cytotoxicity and resistance development potential. This new class of compounds demonstrates efficacy against multiresistant strains and persisters, by depleting membrane potential and creating pores in the cytoplasmic membrane.
JOURNAL OF MEDICINAL CHEMISTRY
(2022)
Article
Chemistry, Applied
Gaston Bravo-Arrepol, Jose Becerra, Leandro Ortiz, Jaime Cabrera-Pardo, Bernd Schmidt, Matthias Heydenreich, Alexandra Kelling, Eric Sperlich, Tomasz M. Karpinski, Cristian Paz
Summary: Furofuran lignanes, which are obtained from various plants, possess important biological activities for treating infectious diseases, inflammatory diseases, and metabolic disorders. In this study, eudesmin, a furofuran lignan, was easily isolated from Araucaria araucana knots using soxhlet extraction and cryo-crystallization. The bromination of eudesmin led to the formation of epieudesmin and its corresponding mono and di-brominated derivatives. The structures of these compounds were determined by NMR and X-ray diffraction. Furthermore, eudesmin exhibited moderate activity against Candida yeast strains, while epieudesmin and the bromine derivatives showed no activity.
NATURAL PRODUCT RESEARCH
(2023)
Article
Endocrinology & Metabolism
Josef Oeckl, Petra Janovska, Katerina Adamcova, Kristina Bardova, Sarah Brunner, Sebastian Dieckmann, Josef Ecker, Tobias Fromme, Jiri Funda, Thomas Gantert, Piero Giansanti, Maria Soledad Hidrobo, Ondrej Kuda, Bernhard Kuster, Yongguo Li, Radek Pohl, Sabine Schmitt, Sabine Schweizer, Hans Zischka, Petr Zouhar, Jan Kopecky, Martin Klingenspor
Summary: We explore different potential sources of UCP1-independent thermogenesis and identify a futile ATP-consuming triglyceride/fatty acid cycle as the main contributor to cellular heat production in brown adipocytes lacking UCP1. We uncover the mechanism on a molecular level and pinpoint the key enzymes involved using pharmacological and genetic interference.
MOLECULAR METABOLISM
(2022)
Article
Chemistry, Physical
Daisuke Sakamoto, Isabel Gay Sanchez, Jiri Rybacek, Jaroslav Vacek, Lucie Bednarova, Marketa Pazderkova, Radek Pohl, Ivana Cisarova, Irena G. Stara, Ivo Stary
Summary: This study describes an asymmetric synthesis method for the preparation of optically pure and conformationally locked oxabenzo[5]helicenes. These compounds can be transformed into cycloiridated organometallics and exhibit excellent catalytic performance in asymmetric transfer hydrogenation reactions.
Article
Chemistry, Multidisciplinary
Vaclav Houska, Egor Ukraintsev, Jaroslav Vacek, Jiri Rybacek, Lucie Bednarova, Radek Pohl, Irena G. Stara, Bohuslav Rezek, Ivo Stary
Summary: The synthesis of helically chiral macrocycles composed of dibenzo[5]helicene units and trans-stilbene-4,4'-diyl linkers is reported. Different stereoisomers of these macrocycles were obtained through chiral resolution. The self-assembly of these macrocycles into long 1D molecular stripes in ordered 2D nanocrystals was studied using AFM.
Article
Plant Sciences
Vaderament-Alexe Nchiozem-Ngnitedem, Eric Sperlich, Valaire Yemene Matieta, Jenifer Reine Ngnouzouba Kuete, Victor Kuete, Ejlal A. A. Omer, Thomas Efferth, Bernd Schmidt
Summary: FicucariconeD and its 4'-demethyl congener 2 are isoflavones obtained from Ficus carica fruits with a 5,7-dimethoxy-6-prenyl-substituted A-ring. They were synthesized for the first time in six steps from 2,4,6-trihydroxyacetophenone. The compounds showed no cytotoxicity against leukemia cell lines but exhibited antimicrobial activities, especially when combined with the efflux pump inhibitor PA beta N.
JOURNAL OF NATURAL PRODUCTS
(2023)
Article
Chemistry, Physical
Radwan M. M. Sarhan, Sergio Kogikoski Jr, Robin M. M. Schuermann, Yuhang Zhao, Andreas Krause, Bernd Schmidt, Ilko Bald, Yan Lu
Summary: This study presents a facile and environmentally friendly method to synthesize black gold nanoparticles via a one-step green synthesis at room temperature using commonly known precursors. The self-assembly of in situ-formed small nanoparticles followed by a fusion step creates extensive networks of nanowires, resulting in strong photothermal and surface-enhanced Raman scattering (SERS) effects. The black gold nanoparticles show potential for applications in solar energy conversion and photothermal therapy.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Plant Sciences
Benson Oloya, Jane Namukobe, Matthias Heydenreich, Willy Ssengooba, Johannes Martin, Heiko Michael Moeller, Bernd Schmidt, Robert Byamukama
Summary: Two new compounds with strong anti-mycobacterial activities were isolated from the root bark of Z. leprieurii, which could potentially serve as new and highly effective drugs for tuberculosis.
PHYTOCHEMISTRY LETTERS
(2023)
Article
Chemistry, Multidisciplinary
Vladimir Motornov, Radek Pohl, Blanka Klepetarova, Petr Beier
Summary: Elusive N-acyl-1,2,3-triazoles formed by direct acylation of NH-1,2,3-triazoles were isolated and characterized. Thermodynamic N2 isomers were found to be preferred. Direct evidence of interconversion between N1- and N2-acyltriazoles confirmed their usefulness in denitrogenative transformations. An efficient synthesis of enamido triflates from NH-triazoles via N2-acyl-1,2,3-triazole intermediates was developed.
CHEMICAL COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
David Kodr, Erika Kuzmova, Radek Pohl, Tomas Kraus, Michal Hocek
Summary: We designed and synthesized lipid-modified dNTPs, which served as substrates for DNA polymerase and could be incorporated simultaneously into the DNA strand. These lipid-ON probes showed enhanced membrane anchoring efficiency and better stability in the cell membrane compared to commonly studied ON analogues. The probes were detected at the cell surface even after 24 hours, indicating their long-lasting effect.
Article
Chemistry, Organic
George Kwesiga, Julia Greese, Alexandra Kelling, Eric Sperlich, Bernd Schmidt
Summary: Isoflavones were synthesized via Suzuki-Miyaura coupling using para-phenolboronic acid and para-methoxybenzene boronic acid as reactants. The optimized conditions led to higher yields of isoflavones.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Adrian Sytniczuk, Mariusz Milewski, Michal Dabrowski, Karol Grela, Anna Kajetanowicz
Summary: A set of macrocyclic unsaturated musk compounds were obtained through a high-concentration RCM process, achieved by forming oligomers and then undergoing backbiting metathesis reaction. The process exhibited high selectivity and yielded pure macrocyclic musk products. The reaction conditions were user-friendly and environmentally friendly, using commercially available catalyst and bio-sourced oleic acid substrates.
Article
Chemistry, Multidisciplinary
Anna Kovalova, Vit Prouza, Martin Zavrel, Miroslav Hajek, Rastislav Dzijak, Alzbeta Magdolenova, Radek Pohl, Zdenek Voburka, Kamil Parkan, Milan Vrabel
Summary: This study presents a method for identifying lectin-binding ligands with low micromolar affinity by screening synthetic click glycopeptide libraries. The selected glycopeptides showed enhanced binding potency to the target lectins compared to the starting sugar moieties. This approach offers a promising alternative means of discovering ligands for galectins and other carbohydrate-binding proteins.
Article
Biochemistry & Molecular Biology
Rebeca Perez, Claudia Figueredo, Viviana Burgos, Jaime R. Cabrera-Pardo, Bernd Schmidt, Matthias Heydenreich, Andreas Koch, Jennifer R. Deuis, Irina Vetter, Cristian Paz
Summary: Maqui, a tree native to Chile, is used by the Mapuche people as an anti-inflammatory agent for the treatment of digestive ailments, fever, and skin lesions. Maqui fruits are considered a superfruit with potential health benefits, including antioxidant, cardioprotective, and anti-inflammatory properties. The leaves of maqui contain alkaloids, polyphenols, and terpenes. The alkaloids, aristoteline and hobartine, were found to inhibit Na(V)1.8, a key Na-V isoform involved in pain sensation, suggesting a potential mechanism for the reported analgesic properties of maqui.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)