Article
Chemistry, Multidisciplinary
Georgia Zahariou, Nikolaos Ioannidis, Yiannis Sanakis, Dimitrios A. Pantazis
Summary: The study reveals the importance of the S-3 state in the water-oxidizing Mn4CaO5 cluster of PSII, as it binds a substrate and precedes O-2 evolution. Methanol-treated PSII shows a previously uncharacterized high-spin species, coexisting with the known intermediate-spin conformation. These results provide insights into the structural heterogeneity of the S-3 state and offer constraints on the S-3 to S-4 transition and the mechanism of O-O bond formation.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Review
Chemistry, Multidisciplinary
Catriona C. James, Bas de Bruin, Joost N. H. Reek
Summary: The importance of transition metal catalysis lies in its wide range of applications, including the synthesis of chemicals, natural products, and pharmaceuticals. However, a relatively new application is the catalysis of new-to-nature reactions inside living cells. The complex environment of living cells poses challenges to transition metal catalysts due to the potential inhibition or deactivation by various biological components. In this review, we summarize the current progress in the field of transition metal catalysis, focusing on the evaluation of catalysis efficiency under living cell and biological conditions. Catalyst poisoning is a common issue in this field, and we suggest that future research should explore physical and kinetic protection strategies to enhance the reactivity of catalysts in cells.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Review
Chemistry, Multidisciplinary
Mikel Oiarbide, Claudio Palomo
Summary: The catalyst-controlled functionalization of unmodified carbonyl compounds is an important operation in organic synthesis, especially when high levels of site- and stereo-selectivity can be achieved. Recent contributions in this field have shown that some subsets of enolizable substrates can now be functionalized through various types of activation mechanisms.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Multidisciplinary
Soohyung Kim, Ha Young Jeong, Seonghan Kim, Hongsik Kim, Sojeong Lee, Jaeheung Cho, Cheal Kim, Dongwhan Lee
Summary: High-valent metal-oxo species play a crucial role in oxygen atom transfer in the catalytic cycles of metalloenzymes. A newly synthesized nickel(II) complex with an amido multidentate ligand demonstrates the feasibility of using peptide backbones as strong electron-donating ligands to stabilize high oxidation states. Protonation in the secondary coordination sphere serves as the entry point to the catalytic cycle, leading to the formation of high-valent nickel species for oxo-transfer reactions.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Chemistry, Physical
Catriona C. James, Petrus C. M. Laan, Bas de Bruin, Joost N. H. Reek
Summary: Olefin metathesis catalysts, such as AquaMet, are susceptible to decomposition under biologically relevant conditions. Current stabilizing strategies have limited applicability under these conditions. Encapsulation of AquaMet within a supramolecular metallocage, with nitrate counterions, enhances the catalyst activity. Replacement of AquaMet's chloride ligands with nitrates through simple anion-exchange leads to higher yields of ring-closed product under aqueous and biological conditions. This kinetic protection strategy of transition metal catalysts may find applications in other in vivo catalytic reactions.
Article
Chemistry, Multidisciplinary
Laia Vicens, Giorgio Olivo, Miquel Costas
Summary: This study presents a supramolecular strategy for enzyme-like H2O2 activation at a biologically inspired manganese catalyst, allowing for catalytic asymmetric epoxidation. Modulation of both amino acid and catalyst structure can tune the efficiency and enantioselectivity of the reaction, and an investigation on the oxidative degradation pathway of the system is provided.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Multidisciplinary
Zhi-Hui Zhang, Qi Zhou, Zhiming Li, Ningjin Zhang, Liang Zhang
Summary: In this study, a two-step, completely stereospecific preparation of a molecular cinquefoil (51) knot with a yield of 86% was reported. The knotted product was obtained through the covalent capture of a pentameric circular helicate. The helical chirality, handedness, and topological writhe of the knot were determined by the absolute configuration of the amino acid ester within the ligand strand. The open helicate exhibited layered packing in the solid state, providing a scaffold for molecularly woven polymers. The transfer of chirality in knot synthesis opens up opportunities for the assembly of other chiral nanotopologies and exploring the consequences of topological stereochemistry in chemistry, materials, and biology.
Article
Biochemistry & Molecular Biology
Dora Lakk-Bogath, Miklos Istvan Szavuly, Patrik Torok, Jozsef Kaizer
Summary: In this paper, a detailed mechanistic study on the Baeyer-Villiger oxidation of cycloketones catalyzed by three iron complexes is described. The study includes the investigation of reaction mechanism and kinetics of key intermediates. These findings contribute to a better understanding of the catalytic mechanism of cycloketone oxidation.
Article
Chemistry, Physical
Catriona C. James, Dinghao Wu, Eduard O. Bobylev, Alexander Kros, Bas de Bruin, Joost N. H. Reek
Summary: This study demonstrates that encapsulating a gold catalyst within a supramolecular cage enhances its reactivity under biological conditions. The encapsulated gold catalyst exhibits higher yields in producing a fluorescent dye compared to the free gold catalyst in aqueous aerobic conditions and in the presence of biological additives. However, the high cytotoxicity of the substrate hinders its transformation inside living cells, limiting the application of this specific reaction. Nevertheless, this research presents a viable strategy to improve the reactivity of gold catalysts in vivo.
Article
Chemistry, Multidisciplinary
Marta Lovisari, Oscar Reid Kelly, Aidan R. McDonald
Summary: By preparing a Ni-II-porphyrin-pi-cation complex ([Ni-II(P center dot+)]), we discovered its capability to oxidize various simple hydrocarbon substrates, and interestingly, some of the products were hydroxylated with the involvement of atmospheric O-2. The kinetic data suggested that the porphyrin-pi-cation radical species utilized a concerted PCET mechanism to oxidize substrates. This finding highlights the potential role of pi-cation radicals as hydrocarbon activators and emphasizes the use of porphyrin ligand non-innocence in oxidation catalyst development.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Princess R. Cabotaje, Kaija Walter, Afridi Zamader, Ping Huang, Felix Ho, Henrik Land, Moritz Senger, Gustav Berggren
Summary: [FeFe] hydrogenases, a type of metalloenzymes, have remarkable catalytic properties and (bio-)technological potential. This study focuses on the Group D hydrogenases, which exhibit relatively low catalytic activity and may have an alternative proton transfer pathway. By analyzing the amino acid residues in Group D hydrogenases, the study provides initial evidence for the existence of this alternative pathway.
Review
Chemistry, Organic
Rajan Archana, Thaipparambil Aneeja, Gopinathan Anilkumar
Summary: This review provides an overview of the research progress in ruthenium-catalyzed allylic amination reactions, including a summary and analysis of the literature up to 2021.
CURRENT ORGANIC CHEMISTRY
(2022)
Review
Chemistry, Applied
Sheng Zhang, Yoshinori Yamamoto, Ming Bao
Summary: Utilizing palladium intermediates for aromatic functionalization reactions is a challenging and significant research topic, as it enables selective functionalization reactions on aromatic rings while inhibiting the formation of traditional products.
ADVANCED SYNTHESIS & CATALYSIS
(2021)
Article
Chemistry, Organic
Kim Greis, Caleb E. Griesbach, Carla Kirschbaum, Gerard Meijer, Gert von Helden, Kevin Pagel, Mark W. Peczuh
Summary: Ferrier reactions involve Lewis acid activation of a cyclic enol ether to generate a glycosyl Ferrier cation through the departure of an allylic leaving group. The resulting cation undergoes attack and transposition, forming a new acetal linkage. This study focuses on the septanosyl Ferrier cation derived from a seven-membered ring carbohydrate-based oxepine. Experimental characterization of the ion, including gas-phase cryogenic IR spectroscopy and solution-phase Ferrier reactions, reveals a preference for contraction to five-membered ring structures in the cation.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Pritam Mondal, Izumi Ishigami, Syun-Ru Yeh, Gayan B. Wijeratne
Summary: This study investigates the mechanism of action of mammalian nitric oxide synthase (NOS) through a NOS model system. The findings provide evidence that heme peroxo intermediates play a crucial role in the oxidation of oximes, leading to the formation of ketones and nitroxyl anions. The results are consistent with previous studies and are supported by recent enzymatic research.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Clinical Neurology
J. L. Guerrero Camacho, T. Corona Vazquez, J. J. Flores Rivera, A. Ochoa Morales, L. Martinez Ruanoa, I. Torres Ramirez de Arellano, D. J. Davila Ortiz de Montellano, A. Jara Prado
Summary: This study aimed to determine the association between the ABCB1 gene variants (C1236T, G2677T/A, and C3435T) and demyelinating disease. The study found that the GG2677/CC3435 genotype combination was associated with demyelinating disease, particularly in men. This study revealed the significant role of the ABCB1 gene in demyelinating disease.
Article
Chemistry, Multidisciplinary
Charafa Souilah, Sergio A. Jannuzzi, Derya Demirbas, Sergei Ivlev, Marcel Swart, Serena DeBeer, Alicia Casitas
Summary: This study discloses a new reactivity mode for electrophilic cyano lambda(3)-iodanes as group transfer one-electron oxidants, which can be used to synthesize Fe-III and Fe-IV cyanide complexes. The synthesis of these complexes was achieved through consecutive single electron transfer processes or oxidation reactions.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Analytical
Rohit Jain, Nanak S. Dhillon, Erik R. Farquhar, Benlian Wang, Xiaolin Li, Janna Kiselar, Mark R. Chance
Summary: Protein footprinting with mass spectrometry is a technique used to study protein structure and interactions. Hydroxyl radical protein footprinting uses OH radicals to label protein side chains. The use of trifluoromethyl chemistry for labeling can improve the resolution of protein side chain labeling in this technique.
ANALYTICAL CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Tong Wu, Khashayar Rajabimoghadam, Ankita Puri, David D. Hebert, Yi Lin Qiu, Sidney Eichelberger, Maxime A. Siegler, Marcel Swart, Michael P. Hendrich, Isaac Garcia-Bosch
Summary: In this research article, a 4H(+)/4e(-) electron-coupled-proton buffer (ECPB) based on Cu and a redox-active ligand is described. The ECPB system catalyzes both the reduction of O-2 to H2O and the dehydrogenation of organic substrates. Mechanistic analysis reveals that fast disproportionation reactions maintain the ECPB equilibrium.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Multidisciplinary
Philipp Heim, Giuseppe Spedalotto, Marta Lovisari, Robert Gericke, John O'Brien, Erik R. Farquhar, Aidan R. McDonald
Summary: In this study, the synthesis of pseudo-trigonal bipyramidal Ni(II) complexes was reported and characterized using various spectroscopic techniques. The reaction of one of the complexes with peroxyphenyl acetic acid (PPAA) resulted in the formation of a terminal Ni=O species. This species showed exceptional reactivity in hydroxylation, epoxidation, and oxygen atom transfer reactions.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Oncology
Jose Alberto Carlos-Escalante, Sonia Iliana Mejia-Perez, Ernesto Soto-Reyes, Lissania Guerra-Calderas, Bernardo Cacho-Diaz, Karla Torres-Arciga, Michel Montalvo-Casimiro, Rodrigo Gonzalez-Barrios, Nancy Reynoso-Noveron, Miguel Ruiz-de la Cruz, Clara Estela Diaz-Velasquez, Silvia Vidal-Millan, Rosa Maria Alvarez-Gomez, Thalia Estefania Sanchez-Correa, Claudio Hiram Pech-Cervantes, Jose Antonio Soria-Lucio, Areli Perez-Castillo, Ana Maria Salazar, Cristian Arriaga-Canon, Felipe Vaca-Paniagua, Aliesha Gonzalez-Arenas, Patricia Ostrosky-Wegman, Alejandro Mohar-Betancourt, Luis A. Herrera, Teresa Corona, Talia Wegman-Ostrosky
Summary: This study investigates the molecular characteristics of astrocytomas in Mexican patients, focusing on AGT, MGMT, and TP53 somatic variants. The presence of AGT and MGMT variants, as well as MGMT promoter methylation, is associated with improved survival and response to chemotherapy. Notably, AGT variants are found exclusively in women, revealing molecular differences between genders in astrocytoma. Further research is needed to validate these findings.
JOURNAL OF NEURO-ONCOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Mayukh Bhadra, Therese Albert, Alicja Franke, Verena Josef, Ivana Ivanovic-Burmazovic, Marcel Swart, Pierre Moenne-Loccoz, Kenneth D. Karlin
Summary: Transition-metal-mediated reductive coupling of nitric oxide (NO(g)) to nitrous oxide (N2O(g)) is significant in various fields. In this study, a detailed mechanism of NO(g) reductive coupling at a copper-ion center was elucidated using density functional theory (DFT). The reaction pathway and intermediates were studied in different solvents, and metastable species were characterized using spectroscopic techniques. The findings provide a comprehensive understanding of NO(g) activation at a reduced Cu site and its implications in different environments.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Clinical Neurology
Yaneth Rodriguez-Agudelo, Jaqueline Nava-Adan, Francisco Paz-Rodriguez, Arturo Abundes-Corona, Jose Flores-Rivera, Teresa Corona
Summary: The COVID-19 pandemic has had a significant impact on the mental health and quality of life of people with Multiple Sclerosis (PwMS). This study found that the unemployment rate increased during the pandemic, and limitations in daily activities had a predominant effect on quality of life. Additionally, the majority of PwMS reported experiencing at least one neuropsychiatric symptom.
MULTIPLE SCLEROSIS AND RELATED DISORDERS
(2023)
Article
Biochemistry & Molecular Biology
Erik R. Farquhar, Kanchustambham Vijayalakshmi, Rohit Jain, Benlian Wang, Janna Kiselar, Mark R. Chance
Summary: Hydroxyl radical protein footprinting is a method to assess protein structure in the solution state using synchrotron radiation. It involves generating hydroxyl radicals through X-ray radiolysis of water, which react with protein side chains and can be detected using mass spectrometry. The optimization of hydroxyl radical dose is typically done using a fluorescence assay, but a direct evaluation of labeling using intact mass spectrometry can provide more accurate and immediate feedback. This method allows for absolute and direct dosimetry for all types of protein footprinting.
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
(2023)
Article
Chemistry, Physical
Eduardo Jaimes-Romano, Hugo Valdes, Simon Hernandez-Ortega, Rosa Mollfulleda, Marcel Swart, David Morales-Morales
Summary: The catalytic activities of three Ni(II) complexes with fluorinated and non-fluorinated N-heterocyclic carbene (NHC) ligands were evaluated in the C-S cross-coupling reaction. The complexes with fluorinated-NHC ligands exhibited lower catalytic activities compared to the non-fluorinated derivative, attributed to the lower electron-donating character of the fluorinated ligands. Different substrates were tested using complex 3-Ni, achieving varying conversions due to differences in the stability of the intermediates formed.
JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Inorganic & Nuclear
Rakesh Kumar, Faiza Ahsan, Ayushi Awasthi, Marcel Swart, Apparao Draksharapu
Summary: The reaction of [(Me/BnTPEN)Ru-II(NCCH3)](2+) with mCPBA in the presence of chloride ions generated a novel (Me/BnTPEN)Ru-III-OCl species. This hypochlorite adduct can also be obtained by the direct reaction of (L)Ru-II complexes with NaOCl and HClO4. The ruthenium hypochlorite adduct catalyzes hydrogen atom abstraction reactions of phenols and their derivatives.
DALTON TRANSACTIONS
(2023)
Article
Chemistry, Physical
Erik Diaz-Cervantes, Juvencio Robles, Miquel Sola, Marcel Swart
Summary: The peptide bond rupture mechanism of the ovarian cancer-related enzyme KLK5 has been studied using three sequential scaled models. The results show that it is a stepwise process involving two proton transfer reactions. The second model with additional residues shows the same trends as the full system and can be considered an appropriate model for studying the peptide bond rupture mechanism.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Biochemistry & Molecular Biology
Priyanka Basak, Diane E. Cabelli, Peter T. Chivers, Erik R. Farquhar, Michael J. Maroney
Summary: This study reveals the involvement of L-histidine in the protease-mediated maturation of nickel-dependent superoxide dismutase (NiSOD), and demonstrates that L-histidine can serve as a metallochaperone to facilitate nickel incorporation.
Article
Chemistry, Multidisciplinary
Mayukh Bhadra, Therese Albert, Alicja Franke, Verena Josef, Ivana Ivanovic-Burmazovic, Marcel Swart, Pierre Moenne-Loccoz, Kenneth D. Karlin
Summary: Transition-metal-mediated reductive coupling of nitric oxide to nitrous oxide has significance in various fields. This study presents a detailed spectroscopic characterization of the reaction mechanism in different solvents.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2023)
Article
Clinical Neurology
Amin Cervantes-Arriaga, Cynthia Sarabia-Tapia, Oscar Esquivel-Zapata, Susana Lopez-Alamillo, Etienne Resendiz-Henriquez, Teresa Corona, Mayela Rodriguez-Violante
Summary: This study conducted a cross-sectional study to identify the factors contributing to diagnostic delay in Parkinson's disease (PD) patients. The results showed that both the individuals with PD and the physicians play important roles in the diagnosis process. Improving disease awareness and medical education on PD could lead to timely diagnosis.
REVISTA MEXICANA DE NEUROCIENCIA
(2022)
