17,765 results match your criteria structurally compounds

The β-hairpin from the Thermus thermophilus HB27 laccase works as a pH-dependent switch to regulate laccase activity.

J Struct Biol 2021 May 4:107740. Epub 2021 May 4.

Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, 2001 Universidad Av., Cuernavaca, Morelos 62210, México. Electronic address:

The multi-copper oxidase from the hyper-thermophilic bacteria Thermus thermophilus (Tth-MCO), has been previously characterized and described as an example of a laccase with low catalytic properties, especially when it is compared with the activity of fungal laccases, but it is active at high temperatures. Structurally, Tth-MCO has a unique feature: a β-hairpin near the T1Cu site, which is not present in any other laccases deposited at the PDB. This β-hairpin has an expected crystallographic behavior in solvent-exposed areas of a crystallized protein: lack of electron density, high B-values and several crystalline contacts with neighboring crystallographic copies; however, its dynamical behavior in solution and its biological implications have not been described. Read More

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Network pharmacology-based identification of the key mechanism of quercetin acting on hemochromatosis.

Metallomics 2021 May 7. Epub 2021 May 7.

College of Animal Sciences, Zhejiang University, Key Laboratory of Animal Feed and Nutrition of Zhejiang Province, Hangzhou, 310058, China.

Hemochromatosis is an iron overload disease, which lacks nutritional intervention strategies. This study explored the protective effect of quercetin on hemochromatosis and its possible mechanism through network pharmacology. We used Online Mendelian Inheritance in Man (OMIM) to screen the disease targets of hemochromatosis, and further constructed a potential protein interaction network through STITCH. Read More

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Structure driven magnetic correlations and magnetodielectric coupling in 6H - perovskite BaDyRuO.

J Phys Condens Matter 2021 May 6. Epub 2021 May 6.

School of Basic Sciences, Indian Institute of Technology Mandi, School of Basic Sciences, Indian Institute of Technology Mandi, Himachal Pradesh, Mandi, Himachal Pradesh, 175075, INDIA.

The 6H-perovskites Ba(R/M)RuO(R = rare earth, M = transition metal) exhibit complex magnetism and have been extensively studied recently for their magnetodielectric (MD) properties. Here, we present a detailed study of structural, magnetic, thermodynamic and MD properties of a 6H-perovskite BaDyRuO. This compound is found to undergo long range antiferromagnetic (AFM) ordering below ∽ 5. Read More

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Crystal structure of 2-[()-2-(4-bromo-phen-yl)diazen-1-yl]-4,5-bis-(4-meth-oxy-phen-yl)-1-imidazole: the first example of a structurally characterized tri-aryl-azo-imid-azole.

Acta Crystallogr E Crystallogr Commun 2021 Mar 26;77(Pt 3):305-308. Epub 2021 Feb 26.

Peoples' Friendship University of Russia, 6 Miklukho-Maklaya Street, Moscow, 117198, Russian Federation.

The title compound, CHBrNO, is a product of an azo coupling reaction between 3,4-bis-(4-meth-oxy-phen-yl)imidazole and 4-bromo-phenyl-diazo-nium tetra-fluoro-borate. Its crystal structure was determined using data collected at 120 K. The mol-ecule adopts a configuration with respect to the N=N double bond. Read More

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Clinically-Relevant ABC Transporter for Anti-Cancer Drug Resistance.

Front Pharmacol 2021 19;12:648407. Epub 2021 Apr 19.

State Key Laboratory of Biotherapy, Cancer Center, West China Hospital, Sichuan University and Collaborative Innovation Center for Biotherapy, Chengdu, China.

Multiple drug resistance (MDR), referring to the resistance of cancer cells to a broad spectrum of structurally and mechanistically unrelated drugs across membranes, severely impairs the response to chemotherapy and leads to chemotherapy failure. Overexpression of ATP binding cassette (ABC) transporters is a major contributing factor resulting in MDR, which can recognize and mediate the efflux of diverse drugs from cancer cells, thereby decreasing intracellular drug concentration. Therefore, modulators of ABC transporter could be used in combination with standard chemotherapeutic anticancer drugs to augment the therapeutic efficacy. Read More

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Novel Cyclohexyl Meroterpenes Produced by Combinatorial Biosynthesis.

Chem Pharm Bull (Tokyo) 2021 ;69(5):444-446

Graduate School of Pharmaceutical Sciences, The University of Tokyo.

Structurally diverse fungal meroterpenoids are promising drug seed compounds. To obtain unnatural, novel meroterpene scaffolds, we tested combinatorial biosynthesis by co-expressing functionally distinct terpene cyclase (TPC) genes, pyr4, ascF, andB, or cdmG, with the biosynthetic genes for the production of a TPC substrate, (10'R)-epoxyfarnesyl-dimethylorsellinic acid-3,5-methyl ester, in Aspergillus oryzae NSAR1 as a heterologous host. As a result, all of the tested TPCs afforded the same two novel mono-cyclization products. Read More

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January 2021

Design and evaluation of 1,2,3-dithiazoles and fused 1,2,4-dithiazines as anti-cancer agents.

Bioorg Med Chem Lett 2021 May 2:128078. Epub 2021 May 2.

Department of Pharmacology, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. Electronic address:

Heteroatom rich 1,2,3-dithiazoles are relatively underexplored in medicinal chemistry. We now report screening data on thirty structurally diverse 1,2,3-dithiazole and electronically related 1,2,4-dithiazines with the aim of identifying interesting starting points for potential future optimisation. The dithiazoles, obtained via a number of different syntheses, were screened on a series of cancer cell lines. Read More

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Contemporary advancements in the semi-synthesis of bioactive terpenoids and steroids.

Org Biomol Chem 2021 May;19(17):3791-3812

Division of Life Science, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong 999077, China.

Many natural products have intriguing biological properties that arise from their fascinating chemical structures. However, the intrinsic complexity of the structural skeleton and the reactive functional groups on natural products pose tremendous challenges to chemical syntheses. Semi-synthesis uses chemical compounds isolated from natural sources as the starting materials to produce other novel compounds with distinct chemical and medicinal properties. Read More

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Computational Identification of Potential Anti-Inflammatory Natural Compounds Targeting the p38 Mitogen-Activated Protein Kinase (MAPK): Implications for COVID-19-Induced Cytokine Storm.

Biomolecules 2021 04 29;11(5). Epub 2021 Apr 29.

Department of Parasitology, Noguchi Memorial Institute for Medical Research, College of Health Sciences, University of Ghana, Legon, Accra P.O. Box LG 581, Ghana.

Severely ill coronavirus disease 2019 (COVID-19) patients show elevated concentrations of pro-inflammatory cytokines, a situation commonly known as a cytokine storm. The p38 MAPK receptor is considered a plausible therapeutic target because of its involvement in the platelet activation processes leading to inflammation. This study aimed to identify potential natural product-derived inhibitory molecules against the p38α MAPK receptor to mitigate the eliciting of pro-inflammatory cytokines using computational techniques. Read More

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Bacterial efflux transporters' polyspecificity - a gift and a curse?

Curr Opin Microbiol 2021 Apr 29;61:115-123. Epub 2021 Apr 29.

Department of Physics, University of Cagliari, 09042 Monserrato (Cagliari), Italy.

All mechanisms of clinical antibiotic resistance benefit from activities of polyspecific efflux pumps acting to reduce intracellular accumulation of toxins and antibiotics. In Gram-negative bacteria, the major polyspecific efflux transporters belong to the Resistance-Nodulation-cell Division (RND) superfamily of proteins, which are capable of expelling thousands of structurally diverse compounds. Recent structural and functional advances generated novel insights into mechanisms underlying the biochemical versatility of RND transporters. Read More

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Rational modification, synthesis and biological evaluation of N-substituted phthalazinone derivatives designed to target interleukine-15 protein.

Bioorg Med Chem 2021 Apr 20;39:116161. Epub 2021 Apr 20.

Université de Nantes, CNRS, Chimie et Interdisciplinarité: Synthèse, Analyse, Modélisation (CEISAM), UMR CNRS 6230, 2, rue de la Houssinière - BP 92208-44322, Nantes, France. Electronic address:

Interleukin (IL)-15 is a pleiotropic cytokine structurally close to IL-2 and sharing with the IL-2Rβ and γc receptor (R) subunits. IL-15 plays important roles in innate and adaptative immunity, supporting the activation and proliferation of NK, NK-T, and CD8 T cells. Over-expression of IL-15 has been shown to participate to the development of inflammatory and autoimmune diseases and diverse T cell malignancies. Read More

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Exploring multi-target inhibitors using approach targeting cell cycle dysregulator-CDK proteins.

J Biomol Struct Dyn 2021 Apr 30:1-15. Epub 2021 Apr 30.

Department of Bioinformatics, Hazara University, Mansehra, Pakistan.

Cyclin-dependent kinases (CDKs) belong to a family of multifunctional enzymes that control cell cycle modifications, transcription, and cell proliferation. Their dysfunctions result in different diseases like cancer making them an important drug target in oncology and beyond. The present study aims at identifying the selective inhibitors for ATP binding site in CDK proteins (CDK1, CDK2, CDK4, and CDK5) following a multi-target drug designing approach. Read More

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Design, synthesis and antitumor activity evaluation of pretubulysin analogs.

Chem Biol Drug Des 2021 Apr 30. Epub 2021 Apr 30.

School of Pharmacy, Key Laboratory of Molecular Pharmacology and Drug Evaluation (Yantai University), Ministry of Education, Collaborative Innovation Center of Advanced Drug Delivery System and Biotech Drugs, Universities of Shandong, Yantai University, Yantai, 264003, China.

Pretubulysin, a biosynthetic precursor of the tubulysins, shows potent biological activity in a variety of tumor cell lines. Although there are several total synthesis routes to tubulysin and pretubulysin reported, the commercialization still has been hampered due to the complexity of the structure. To find structurally simpler pretubulysin analogs, a series of 2-(3-(methylamino)propyl)thiazole-4-carboxamides are designed and synthesized, and their anticancer activities are screened using MCF-7 (breast cancer), and NCI-H157 (lung cancer) cell lines. Read More

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Highly Branched Polymers Based on Poly(amino acid)s for Biomedical Application.

Nanomaterials (Basel) 2021 Apr 26;11(5). Epub 2021 Apr 26.

Department of Chemistry, University of Alabama in Huntsville, 301 Sparkman Dr., Huntsville, AL 35899, USA.

Polymers consisting of amino acid building blocks continue to receive consideration for biomedical applications. Since poly(amino acid)s are built from natural amino acids, the same building blocks proteins are made of, they are biocompatible, biodegradable and their degradation products are metabolizable. Some amino acids display a unique asymmetrical AB2 structure, which facilitates their ability to form branched structures. Read More

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Discovery of New Small Molecule Hits as Hepatitis B Virus Capsid Assembly Modulators: Structure and Pharmacophore-Based Approaches.

Viruses 2021 04 27;13(5). Epub 2021 Apr 27.

Center for Drug Design, College of Pharmacy, University of Minnesota, Minneapolis, MN 55455, USA.

Hepatitis B virus (HBV) capsid assembly modulators (CpAMs) have shown promise as potent anti-HBV agents in both preclinical and clinical studies. Herein, we report our efforts in identifying novel CpAM hits via a structure-based virtual screening against a small molecule protein-protein interaction (PPI) library, and pharmacophore-guided compound design and synthesis. Curated compounds were first assessed in a thermal shift assay (TSA), and the TSA hits were further evaluated in an antiviral assay. Read More

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Phytochemical Analysis of the Fruits of Sea Buckthorn (): Identification of Organic Acid Derivatives.

Plants (Basel) 2021 Apr 24;10(5). Epub 2021 Apr 24.

School of Pharmacy, Sungkyunkwan University, Suwon 16419, Korea.

L. (Elaeagnaceae), commonly known as "Sea buckthorn" and "Vitamin tree", is a spiny deciduous shrub whose fruit is known for its nutritional composition, such as vitamin C, and is consumed as a dietary supplement worldwide. As part of our ongoing efforts to identify structurally new and bioactive constituents from natural resources, the phytochemical investigation of the extract of fruits led to the isolation of one malate derivative (), five citrate derivatives (), and one quinate derivative (). Read More

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Design, Synthesis, and Antibacterial Screening of Some Novel Heteroaryl-Based Ciprofloxacin Derivatives as DNA Gyrase and Topoisomerase IV Inhibitors.

Pharmaceuticals (Basel) 2021 Apr 22;14(5). Epub 2021 Apr 22.

Department of Chemistry, Faculty of Science, Sohag University, Sohag 82524, Egypt.

A novel series of ciprofloxacin hybrids comprising various heterocycle derivatives has been synthesized and structurally elucidated using H NMR, C NMR, and elementary analyses. Using ciprofloxacin as a reference, compounds were screened in vitro against Gram-positive bacterial strains such as and and Gram-negative strains such as and . As a result, many of the compounds examined had antibacterial activity equivalent to ciprofloxacin against test bacteria. Read More

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Facile Synthesis and In Vitro Activity of -Substituted 1,2-Benzisothiazol-3(2)-ones against Dengue Virus NS2BNS3 Protease.

Pathogens 2021 Apr 12;10(4). Epub 2021 Apr 12.

Institut für Virologie und Immunbiologie, Versbacher Straße 7, 97078 Würzburg, Germany.

Several new -substituted 1,2-benzisothiazol-3(2)-ones (BITs) were synthesised through a facile synthetic route for testing their anti-dengue protease inhibition. Contrary to the conventional multistep synthesis, we achieved structurally diverse BITs with excellent yields using a two-step, one-pot reaction strategy. All the synthesised compounds were prescreened for drug-like properties using the online Swiss Absorption, Distribution, Metabolism and Elimination (SwissADME) model, indicating their favourable pharmaceutical properties. Read More

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Discovery of Potential, Dual-Active Histamine H Receptor Ligands with Combined Antioxidant Properties.

Molecules 2021 Apr 15;26(8). Epub 2021 Apr 15.

Department of Technology and Biotechnology of Drugs, Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna 9, 30-699 Kraków, Poland.

In an attempt to find new dual acting histamine H receptor (HR) ligands, we designed a series of compounds, structurally based on previously described in our group, a highly active and selective human histamine H receptor (hHR) ligand KSK63. As a result, 15 obtained compounds show moderate hHR affinity, the best being the compound (hHR = 518 nM). Docking to the histamine HR homology model revealed two possible binding modes, with key interactions retained in both cases. Read More

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In Silico Identification of Small Molecules as New Cdc25 Inhibitors through the Correlation between Chemosensitivity and Protein Expression Pattern.

Int J Mol Sci 2021 Apr 2;22(7). Epub 2021 Apr 2.

Dipartimento di Scienze e Tecnologie Biologiche Chimiche e Farmaceutiche "STEBICEF", University of Palermo, Viale delle Scienze Ed. 17, I-90128 Palermo, Italy.

The cell division cycle 25 (Cdc25) protein family plays a crucial role in controlling cell proliferation, making it an excellent target for cancer therapy. In this work, a set of small molecules were identified as Cdc25 modulators by applying a mixed ligand-structure-based approach and taking advantage of the correlation between the chemosensitivity of selected structures and the protein expression pattern of the proposed target. In the first step of the in silico protocol, a set of molecules acting as Cdc25 inhibitors were identified through a new ligand-based protocol and the evaluation of a large database of molecular structures. Read More

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Removing of the Sulfur Compounds by Impregnated Polypropylene Fibers with Silver Nanoparticles-Cellulose Derivatives for Air Odor Correction.

Membranes (Basel) 2021 Apr 1;11(4). Epub 2021 Apr 1.

Department of Analytical Chemistry and Environmental Engineering, University Politehnica of Bucharest, 1-7 Gheorghe Polizu St., 011061 Bucharest, Romania.

The unpleasant odor that appears in the industrial and adjacent waste processing areas is a permanent concern for the protection of the environment and, especially, for the quality of life. Among the many variants for removing substance traces, which give an unpleasant smell to the air, membrane-based methods or techniques are viable options. Their advantages consist of installation simplicity and scaling possibility, selectivity; moreover, the flows of odorous substances are direct, automation is complete by accessible operating parameters (pH, temperature, ionic strength), and the operation costs are low. Read More

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Heparin: A simplistic repurposing to prevent SARS-CoV-2 transmission in light of its in-vitro nanomolar efficacy.

Int J Biol Macromol 2021 Apr 26;183:203-212. Epub 2021 Apr 26.

Infectious Diseases, Mayo Clinic, Jacksonville, FL, USA. Electronic address:

The world is currently facing a novel coronavirus (SARS-CoV-2) pandemic. The greatest threat that is disrupting the normal functioning of society is the exceptionally high species independent transmission. Drug repurposing is understood to be the best strategy to immediately deploy well-characterized agents against new pathogens. Read More

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Silylated Sulfuric Acid: Preparation of a Tris(trimethylsilyl)oxo-sulfonium [(Me3Si-O)3SO]+ Salt.

Angew Chem Int Ed Engl 2021 Apr 29. Epub 2021 Apr 29.

Universität Rostock: Universitat Rostock, Chemie, GERMANY.

The chemistry of silylated sulfuric acid, O 2 S(OSiMe 3 ) 2 (T 2 SO 4 , T = Me 3 Si; also known as bis(trimethylsilyl) sulfate), has been studied in detail with the aim of synthesizing the formal autosilylation products of silylated sulfuric acid, [T 3 SO 4 ] + and [TSO 4 ] - , in analogy to the known protonated species, [H 3 SO 4 ] + and [HSO 4 ] - . The synthesis of the [TSO 4 ] - ion only succeeds when a base, such as OPMe 3 that forms a weakly coordinating cation upon silylation, is reacted with T 2 SO 4 , resulting in the formation of [Me 3 POT] + [TSO 4 ] - . [T 3 SO 4 ] + salts could be isolated starting from T 2 SO 4 in the reaction with [T-H-T] + [B(C 6 F 5 ) 4 ] - or T + [CHB 11 Br 6 H 5 ] - when a weakly coordinating anion is used as counterion. Read More

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Molecular characterization of and gene in .

Saudi J Biol Sci 2021 Apr 23;28(4):2301-2315. Epub 2021 Jan 23.

Atta-ur-Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad 44000, Pakistan.

(peanut) is a potential source of bioactive compounds including flavonols and proanthocyanidins, which have gained particular interest of metabolic engineering owing to their significance in the growth, development and defense responses in plants. To gain insight of proanthocyanidins and flavonols production in , and enzymes responsible for their production, have been structurally, transcriptionally and functionally characterized. Structural and functional analysis of putative protein sequence of indicated two functional motifs 2OG-FeII_Oxy and DIOX_N while six functional motifs belonging to the families of NAD-dependent dehydratase, 3, and NmrA-like family were observed in case of Promoter sequence analysis unraveled several promoter elements related to the development regulation, environmental stress responses and hormonal signaling. Read More

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New oxindole alkaloids with selective osteoclast inhibitory activity from .

Nat Prod Res 2021 Apr 28:1-7. Epub 2021 Apr 28.

Guizhou University of Traditional Chinese Medicine, Guiyang, People's Republic of China.

A new alkaloid 14-hydroxygelseziridine (), along with four known oxindoles (), was isolated and characterized from the well-known toxic medicine . Their structures were elucidated by means of spectroscopic techniques and quantum chemistry calculations. Structurally, new compound has a three membered oxygen ring at -4/C-20. Read More

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Systematic evaluation of a panel of 30 synthetic cannabinoid receptor agonists structurally related to MMB-4en-PICA, MDMB-4en-PINACA, ADB-4en-PINACA and MMB-4CN-BUTINACA using a combination of binding and different CB1 receptor activation assays PART III: The G protein pathway and critical comparison of different assays.

Drug Test Anal 2021 Apr 27. Epub 2021 Apr 27.

Institute of Forensic Medicine, Forensic Toxicology, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany.

The present work is the last of a three-part study investigating a panel of 30 systematically designed synthetic cannabinoid receptor agonists (SCRAs) including features such as the 4-pentenyl tail and varying head groups including amides and esters of L-valine (MMB, AB), L-tert-leucine (ADB), and L-phenylalanine (APP), as well as adamantyl (A) and cumyl moieties (CUMYL). Here, we evaluated these SCRAs for their capacity to activate the human cannabinoid receptor 1 (CB ) via indirect measurement of G protein recruitment. Furthermore, we comparatively evaluated the results obtained from three in vitro assays, based on the recruitment of β-arrestin 2 (βarr2 assay) or Gα protein (mini-Gα assay), or binding of [ S]-GTPγS. Read More

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Tuning NO release of organelle-targeted furoxan derivatives and their cytotoxicity against lung cancer cells.

Bioorg Chem 2021 Apr 20;111:104911. Epub 2021 Apr 20.

Department of Drug Science and Technology, University of Torino, 10125 Torino, Italy.

We herein report a study on a set of hybrid compounds in which 3-R-substituted furoxan moieties (R = CH, CONH, CN, SOCH), endowed with varying NO-releasing capacities, are joined to a mitochondrial probe, rhodamine B. Each product has been investigated for its ability to release NO both in physiological solution, in the presence of cysteine, and in A549 lung adenocarcinoma cancer cells. The cytotoxicity of all the products against the aforementioned cancer cells has been assessed, including the structurally related compounds with no mitochondrial targeting, which were taken as a reference. Read More

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Thermally activated delayed fluorescence and phosphorescence quenching in iminophosphonamide copper and zinc complexes.

Chemistry 2021 Apr 26. Epub 2021 Apr 26.

KIT: Karlsruher Institut fur Technologie, Institute of Nanotechnology, GERMANY.

The synthesis of copper and zinc complexes of four variably substituted iminophosphonamide ligands is presented. While the copper complexes form ligand bridged dimers, the zinc compounds are monomeric. Due to different steric demand of the ligand the arrangement of the ligands within the dimeric complexes varies. Read More

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Phenoxazine nucleoside derivatives with a multiple activity against RNA and DNA viruses.

Eur J Med Chem 2021 Apr 15;220:113467. Epub 2021 Apr 15.

Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, 117997, Russia. Electronic address:

Emerging and re-emerging viruses periodically cause outbreaks and epidemics all over the world, eventually leading to global events such as the current pandemic of the novel SARS-CoV-2 coronavirus infection COVID-19. Therefore, an urgent need for novel antivirals is crystal clear. Here we present the synthesis and evaluation of an antiviral activity of phenoxazine-based nucleoside analogs divided into three groups: (1) 8-alkoxy-substituted, (2) acyclic, and (3) carbocyclic. Read More

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Discovery of selective fragment-sized immunoproteasome inhibitors.

Eur J Med Chem 2021 Apr 20;219:113455. Epub 2021 Apr 20.

University of Ljubljana, Faculty of Pharmacy, Aškerčeva cesta 7, SI-1000, Ljubljana, Slovenia. Electronic address:

Proteasomes contribute to maintaining protein homeostasis and their inhibition is beneficial in certain types of cancer and in autoimmune diseases. However, the inhibition of the proteasomes in healthy cells leads to unwanted side-effects and significant effort has been made to identify inhibitors specific for the immunoproteasome, especially to treat diseases which manifest increased levels and activity of this proteasome isoform. Here, we report our efforts to discover fragment-sized inhibitors of the human immunoproteasome. Read More

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