Review
Chemistry, Multidisciplinary
Harri Lonnberg
Summary: The cleavage of RNA phosphodiester bonds by RNase A and hammerhead ribozyme at neutral pH differs from spontaneous reactions. Comparative kinetic measurements, heavy atom isotope effects, and theoretical calculations help clarify the mechanistic details and provide a basis for more complex catalytic mechanisms.
Article
Engineering, Environmental
Pierre Albrand, Carine Julcour, Florian Veyrine, Anne-Marie Billet
Summary: In this study, a kinetic model for sunflower oil hydrogenation on a palladium catalyst was proposed based on Horiuty-Polanyi type mechanism, considering either dissociative or associative adsorption of hydrogen. The kinetic parameters were identified through batch slurry hydrogenations, and statistical analysis was used to select the most suitable adsorption mechanism for H-2. The evaluation of the Weisz-Prater modulus indicated limitations to intraparticle diffusion despite the particle diameter not exceeding 40 μm.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Multidisciplinary Sciences
Mario P. Wiesenfeldt, James A. Rossi-Ashton, Ian B. Perry, Johannes Diesel, Olivia L. Garry, Florian Bartels, Susannah C. Coote, Xiaoshen Ma, Charles S. Yeung, David J. Bennett, David W. C. MacMillan
Summary: The replacement of benzene rings with sp(3)-hybridized bioisosteres in drug candidates generally improves pharmacokinetic properties while retaining biological activity. Rigid, strained frameworks such as bicyclo[1.1.1]pentane and cubane are particularly well suited as the ring strain imparts high bond strength and thus metabolic stability on their C-H bonds. We report expedient routes to 1,3- and 1,2-disubstituted cubane building blocks using a convenient cyclobutadiene precursor and a photolytic C-H carboxylation reaction, respectively, and develop cross-coupling protocols using copper as a catalyst. Our research enables facile elaboration of all cubane isomers into drug candidates, thus enabling ideal bioisosteric replacement of ortho-, meta-, and para-substituted benzenes.
Article
Engineering, Environmental
Emil Bein, Millaray Sierra Olea, Sophie Petersen, Joerg E. Drewes, Uwe Huebner
Summary: This study investigates the reaction kinetics and pathways of gabapentin (GBP) during ozone treatment. The results show that the direct reaction between GBP and ozone is slow and pH-dependent, while the deprotonated species shows a comparable rate constant to other amine compounds. LC-MS/MS measurements reveal that ozonation of GBP leads to the formation of a carboxylic acid group and simultaneous nitrate formation. Experiments with isotopically labeled ozone suggest that the intermediate aldehyde does not include any oxygen from ozone. Overall, this study provides insights into the reaction mechanisms of aliphatic primary amines during wastewater ozonation.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Engineering, Chemical
Helei Liu, Xiaotong Jiang, Raphael Idem, Shoulong Dong, Paitoon Tontiwachwuthikul
Summary: In this study, the kinetics of CO2 absorption in 1DMA2P solution were experimentally measured and a numerical kinetics model was developed. The model was validated by comparing with experimental data and showed a good agreement. The study provides an effective criterion for solvent screening.
Article
Thermodynamics
Huanhuan Wang, Lili Xing, Cheng Xie, Bingzhi Liu, Hong Wang, Zhandong Wang
Summary: This work investigates the H-abstraction reaction, isomerization, and α-dissociation of isopentanol using quantum chemical theory and kinetic methods. The study finds that H-abstraction by H atoms follows the Evans-Polanyi principle, and isomerization dominates at low temperatures while α-C-C bond dissociation dominates at high temperatures.
COMBUSTION AND FLAME
(2022)
Article
Chemistry, Physical
Yuqing Xu, Michael E. Harris, Darrin M. York, Kin-Yiu Wong
Summary: RNA strand cleavage can be catalyzed by both ribozymes and hydroxide or hydronium ions. Experiments showed that cleavage of the 5'-linked nucleoside and isomerization between 3',5'- and 2',5'-phosphodiesters occur under acidic conditions, while only cleavage reaction is observed under basic conditions. A path-integral approach was used to reveal the reaction mechanisms under acidic conditions, and the proposed mechanisms can also be supported by experimental pH-rate profiles.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2023)
Article
Agricultural Engineering
Misa Mojca Cajnko, Jost Oblak, Miha Grilc, Blaz Likozar
Summary: Enzymes play a crucial role in lignin valorization, with different enzymes involved in various elementary reaction mechanisms. Degradation of lignin depends on enzyme activity and the interaction with proteins in ways that target specific covalent bonds in lignin. Various factors influence enzymatic activity, which must be taken into consideration for optimal functionality and synthesis yields.
BIORESOURCE TECHNOLOGY
(2021)
Article
Chemistry, Inorganic & Nuclear
Jun Shu, Jian Yue, Xin Qiu, Xiaoqiang Liu, Wang Ren, Qianli Li, Yulong Li, Bin Xu, Kaiming Zhang, Weidong Jiang
Summary: In this study, three transition metal binuclear complexes were synthesized and tested for their ability to cleave phosphate diesters, c-Myc oligonucleotides, and plasmid DNA. However, the tested complexes displayed low activity, mainly attributed to the lack of bimetallic cooperation due to a relatively larger metal-metal distance. Among the complexes, Co2LCl4 showed the highest activity in the hydrolysis reaction according to density function theory calculation. Only Cu2LCl4 exhibited catalytic activity for oxidative cleavage of substrates in this work, and the Cu2LCl4-mediated oxidative cleavage was significantly more efficient compared to hydrolytic cleavage.
INORGANIC CHEMISTRY FRONTIERS
(2021)
Article
Chemistry, Physical
Meng Yang, Caiyue Liao, Chenglong Tang, Peng Zhang, Zuohua Huang, Jianling Li
Summary: The potential energy surfaces of three nitrotoluene isomers were theoretically constructed, revealing differences in the isomerization pathways and high energy barriers for the reactions. Reactions involving -NO2 isomerizing to ONO and C-NO2 bond dissociation were found to play important roles among the initial channels for p-nitrotoluene and m-nitrotoluene, while H atom migration and C-NO2 bond dissociation were dominant for o-nitrotoluene. Rate constant calculations showed that O transfer isomerization reactions are prominent at low to intermediate temperatures, with direct C-NO2 bond dissociation prevailing at high temperatures for p-nitrotoluene and m-nitrotoluene, and H atom migration being predominant for o-nitrotoluene.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Srinivas Kolluru, Manvendra Singh, Bryce Gaskins, Zarko Boskovic
Summary: The study reports a nickel-catalyzed annulation reaction between o-haloarylimines and electron-poor olefins, leading to the formation of two adjacent anti stereocenters and a free secondary amine. The research characterized the key oxidative addition intermediate, identified a major path to competing products, and determined the activation energy and rate of oxidative addition complex isomerization. The sensitivity of the reaction to reaction conditions was quantitatively established, and both the scope and limitations of the method were presented.
Article
Chemistry, Multidisciplinary
Haibo Wu, Cristiana Margarita, Jira Jongcharoenkamol, Mark D. Nolan, Thishana Singh, Pher G. Andersson
Summary: In this study, the first iridium-catalyzed kinetic resolution of a wide range of trisubstituted secondary and tertiary allylic alcohols was described, showing large selectivity factors and high levels of enantiopurity. The utility of this method was demonstrated in the enantioselective formal synthesis of some bioactive natural products, highlighting its potential application value in organic compound synthesis.
Article
Biochemistry & Molecular Biology
Aida Montserrat Pages, Maarten Hertog, Bart Nicolai, Dragana Spasic, Jeroen Lammertyn
Summary: A mathematical model describing and predicting the reaction of a 10-23 RNA-cleaving DNAzyme is presented for the first time, expanding the range of conditions in which the model can be used.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Review
Chemistry, Multidisciplinary
Radoslaw Michalski, Renata Smulik-Izydorczyk, Jakub Pieta, Monika Rola, Angelika Artelska, Karolina Pierzchala, Jacek Zielonka, Balaraman Kalyanaraman, Adam Bartlomiej Sikora
Summary: This review focuses on the chemistry of HNO, particularly on reaction kinetics and mechanisms in aqueous solutions. The increasing interest in the biological chemistry of HNO is due to the numerous pharmacological benefits of its donors.
FRONTIERS IN CHEMISTRY
(2022)
Article
Environmental Sciences
Afzal Ahmed Dar, Bao Pan, Jiani Qin, Qiuhui Zhu, Eric Lichtfouse, Muhammad Usman, Chuanyi Wang
Summary: This review evaluates the application of ferrate (Fe(VI)) as a green coagulant and reactive oxidant for removing micro pollutants, particularly pharmaceutical pollutants in contaminated water. The study summarizes the nature, reactivity, and chemistry of Fe(VI) oxidation, as well as different mechanisms and reactive agents involved in contaminant degradation. Various Fe(VI) application methods and activating agents are discussed, along with innovative aspects to improve stability and effectiveness in degrading micro pollutants in water.
ENVIRONMENTAL POLLUTION
(2021)
Article
Chemistry, Multidisciplinary
Dattatraya Uttam Ukale, Petri Tahtinen, Tuomas Lonnberg
CHEMISTRY-A EUROPEAN JOURNAL
(2020)
Article
Chemistry, Physical
Lange Yakubu Saleh, Mikko Ora, Tuomas Lonnberg
Article
Biochemistry & Molecular Biology
Sajal Maity, Madhuri Hande, Tuomas Lonnberg
Article
Biochemistry & Molecular Biology
Asmo Aro-Heinila, Tuomas Lonnberg, Pasi Virta
Summary: By incorporating a highly nucleobase-discriminating metalated nucleoside analogue into an oligonucleotide molecular beacon, clear binding selectivity was achieved at room temperature, with a preference order of G>T>C>A. This method allows for robust discrimination between different nucleobases and is suitable for the detection of single nucleotide polymorphisms.
Article
Astronomy & Astrophysics
Esko Gardner, Harry J. Lehto, Kirsi Lehto, Nicolas Fray, Anais Bardyn, Tuomas Lonnberg, Sihane Merouane, Robin Isnard, Herve Cottin, Martin Hilchenbach
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2020)
Article
Biochemistry & Molecular Biology
Lange Yakubu Saleh, Mikko Ora, Tuomas Lonnberg
Summary: A water-soluble arylmercury complex has been synthesized and its ability to catalyze the cleavage of the phosphodiester linkage of the RNA model compound has been evaluated. The catalytic reaction is linearly dependent on catalyst concentration and shows relatively low affinity for the substrate.
Review
Biochemistry & Molecular Biology
Dattatraya Ukale, Tuomas Lonnberg
Summary: This review summarizes the synthetic efforts towards nucleosides, nucleotides, oligonucleotides, and nucleic acids covalently mercurated at their base moieties, as well as discusses the proposed, realized, and abandoned applications of such compounds. Emphasis is placed on ongoing research areas, particularly the use of Hg-II-mediated base pairing to enhance the hybridization properties of oligonucleotide probes. The review also aims to anticipate potential future applications of organomercury nucleic acids.
Article
Biochemistry & Molecular Biology
Madhuri Hande, Sajal Maity, Tuomas Lonnberg
Summary: The study investigated the effects of alkylpyridine C-nucleoside derivatives or respective palladacycles on short oligodeoxynucleotides, revealing a decrease in duplex stability upon palladation. Competition experiments showed a more pronounced impact at the 3' terminus compared to the 5' terminus. The dependence of UV melting temperature on the identity of canonical nucleobases opposite to modified nucleobases was more significant in the palladacyclic duplexes.
JOURNAL OF INORGANIC BIOCHEMISTRY
(2021)
Article
Chemistry, Organic
Asmo Aro-Heinila, Assi Lepisto, Antti Aarela, Tuomas Antti Lonnberg, Pasi Virta
Summary: A novel organomercury nucleobase analogue was synthesized and incorporated into an oligonucleotide, followed by mercuration. The affinity of the organomercury nucleobase analogue towards complementary strands was studied using UV, CD, and F-19 NMR spectroscopy, revealing distinct affinities for different canonical nucleobases. Results showed that the F-19 resonance signal was sensitive to local environmental changes, providing valuable information on the binding of the mercurated oligonucleotide to complementary strands at varying temperatures.
JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Organic
Josefiina Wallin, Tuomas Lonnberg
Summary: The dependence of the hydrolysis rate of a series of N-methoxy-2-phenyl-1,3-oxazinanes on the Hammett substituent constant of the substituent of the phenyl ring was determined. Based on this information, 4-(benzoyloxy)benzaldehyde was selected as a protecting group for a new (2R,3S)-4-(methoxyamino)butane-1,2,3-triol phosphoramidite building block. The yield of the preparation of this building block as well as its coupling in automated oligonucleotide synthesis were greatly improved compared to the method reported previously.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Tharun K. Kotammagari, Petri Tahtinen, Tuomas Lonnberg
Summary: Short oligonucleotides containing organometallic moieties were synthesized and studied as hybridization probes for sequences containing thiopyrimidine nucleobases. They showed stable duplex formation with 4-thiothymine and were able to discriminate between 2- and 4-thiothymine based on the melting temperature. The DFT-optimized structures revealed the coordination and bonding patterns between Hg-II ions and sulfur or oxygen substituents.
CHEMISTRY-A EUROPEAN JOURNAL
(2022)
Article
Chemistry, Organic
Maaret Toiviala, Vesa Kleemola, Sajal Maity, Tuomas Lonnberg
Summary: Both alpha and beta anomers of an acetophenone C-nucleoside were synthesized and incorporated in the middle of short oligodeoxynucleotides. The ketone oligonucleotides were converted to N-15-labelled oxime oligonucleotides and cyclopalladated. Comparison of the UV melting profiles suggested formation of a stable Pd(II)-mediated base pair with adenine or thymine as the base pairing partner. The N-15 NMR spectra indicated successful labeling, but the signals diminished below detection limit when hybridized with a complementary strand in a specific configuration.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Lange Yakubu Saleh, Mikko Ora, Tuomas Lonnberg
Summary: Two oligonucleotide conjugates were synthesized with different 5'-terminal organometallic moieties through direct mercuration or oximation. These conjugates exhibited higher catalytic activity as artificial ribonucleases compared to metal-free counterparts and previously reported small molecule organomercury RNA cleaving agent. However, the activity was modest compared to state-of-the-art metal-dependent artificial ribonucleases.
JOURNAL OF INORGANIC BIOCHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Mark N. K. Afari, Kasper Nurmi, Pasi Virta, Tuomas Lonnberg
Summary: Hairpin oligodeoxynucleotides with a modified residue in the stem were synthesized and reacted with aromatic aldehydes to produce nucleoside analogues. The reaction equilibrium depends on the aldehyde and nucleobase. The modified residue showed the highest affinity and selectivity with 9-formyl-9-deazaadenine.
Article
Chemistry, Organic
Mark N. K. Afari, Pasi Virta, Tuomas Lonnberg
Summary: In this study, (2R,3S)-4-(methoxyamino)butane-1,2,3-triol was converted into a protected phosphoramidite building block and incorporated into short DNA oligonucleotides, replacing the furanose ring with an oxazinane ring through reaction with aldehydes. This approach demonstrated the feasibility of synthesizing base-modified oligonucleotides using aromatic and aliphatic aldehydes with various functional groups.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2022)