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1.	Andersson, Per Ola, et al. (author) Towards Fingermark Dating : A Raman Spectroscopy Proof-of-Concept Study 2017 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 6:6, s. 706-709 Journal article (peer-reviewed)abstract Fingermarks have, for a long time, been vital in the forensic community for the identification of individuals, and a possibility to non-destructively date the fingermarks would of course be beneficial. Raman spectroscopy is, herein, evaluated for the purpose of estimating the age of fingermarks deposits. Well-resolved spectra were non-destructively acquired to reveal spectral uniqueness, resembling those of epidermis, and several molecular markers were identified that showed different decay kinetics: carotenoids > squalene > unsaturated fatty acids > proteins. The degradation rates were accelerated, less pronounced for proteins, when samples were stored under ambient light conditions, likely owing to photo-oxidation. It is hypothesized that fibrous proteins are present and that oxidation of amino acid side chains can be observed both through Raman and fluorescence spectroscopy. Clearly, Raman spectroscopy is a useful technique to non-destructively study the aging processes of fingermarks.
2.	Arja, Katriann, et al. (author) Synthesis and Characterization of Novel Fluoro-glycosylated Porphyrins that can be Utilized as Theranostic Agents 2018 In: ChemistryOpen. - : Wiley-VCH Verlagsgesellschaft. - 2191-1363. ; 7:7, s. 495-503 Journal article (peer-reviewed)abstract Small molecules with modalities for a variety of imaging techniques as well as therapeutic activity are essential, as such molecules render opportunities to simultaneously conduct diagnosis and targeted therapy, so called theranostics. In this regard, glycoporphyrins have proven useful as theranostic agents towards cancer, as well as noncancerous conditions. Herein, the synthesis and characterization of heterobifunctional glycoconjugated porphyrins with two different sugar moieties, a common monosaccharide at three sites, and a 2-fluoro-2-deoxy glucose (FDG) moiety at the fourth site are presented. The fluoro-glycoconjugated porphyrins exhibit properties for multimodal imaging and photodynamic therapy, as well as specificity towards cancer cells. We foresee that our findings might aid in the chemical design of heterobifunctional glycoconjugated porphyrins that could be utilized as theranostic agents.
3.	Behrends, Malte, et al. (author) N-Aryl Isoleucine Derivatives as Angiotensin II AT(2) Receptor Ligands 2014 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 3:2, s. 65-75 Journal article (peer-reviewed)abstract A novel series of ligands for the recombinant human AT(2) receptor has been synthesized utilizing a fast and efficient palladium-catalyzed procedure for aminocarbonylation as the key reaction. Molybdenum hexacarbonyl [Mo(CO)(6)] was employed as the carbon monoxide source, and controlled microwave heating was applied. The prepared N-aryl isoleucine derivatives, encompassing a variety of amide groups attached to the aromatic system, exhibit binding affinities at best with K-i values in the low micromolar range versus the recombinant human AT(2) receptor. Some of the new nonpeptidic isoleucine derivatives may serve as starting points for further structural optimization. The presented data emphasize the importance of using human receptors in drug discovery programs.
4.	Bielawski, Marcin, et al. (author) One-Pot Synthesis and Applications of N-Heteroaryl Iodonium Salts 2014 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 3:1, s. 19-22 Journal article (peer-reviewed)abstract An efficient one-pot synthesis of N-heteroaryl iodonium triflates from the corresponding N-heteroaryl iodide and arene has been developed. The reaction conditions resemble our previous one-pot syntheses, with suitable modifications to allow N-heteroaryl groups. The reaction time is only 30min, and no anion exchange is required. The obtained iodonium salts were isolated in a protonated form, these salts can either be employed directly in applications or be deprotonated prior to use. The aryl groups were chosen to induce chemoselective transfer of the heteroaryl moiety to various nucleophiles. The reactivity and chemoselectivity of these iodonium salts were demonstrated by selectively introducing a pyridyl moiety onto both oxygen and carbon nucleophiles in good yields.
5.	Borhade, Sanjay R, et al. (author) Inhibition of Insulin-Regulated Aminopeptidase (IRAP) by Arylsulfonamides 2014 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 3:6, s. 256-263 Journal article (peer-reviewed)abstract The inhibition of insulin-regulated aminopeptidase (IRAP, EC 3.4.11.3) by angiotenesin IV is known to improve memory and learning in rats. Screening 10 500 low-molecular-weight compounds in an enzyme inhibition assay with IRAP from Chinese Hamster Ovary (CHO) cells provided an arylsulfonamide (N-(3-(1H-tetrazol-5-yl)phenyl)-4-bromo-5-chlorothiophene-2-sulfonamide), comprising a tetrazole in the meta position of the aromatic ring, as a hit. Analogues of this hit were synthesized, and their inhibitory capacities were determined. A small structure-activity relationship study revealed that the sulfonamide function and the tetrazole ring are crucial for IRAP inhibition. The inhibitors exhibited a moderate inhibitory potency with an IC50=1.1±0.5 μm for the best inhibitor in the series. Further optimization of this new class of IRAP inhibitors is required to make them attractive as research tools and as potential cognitive enhancers.
6.	Bäck, Marcus, et al. (author) Tyrosine Side-Chain Functionalities at Distinct Positions Determine the Chirooptical Properties and Supramolecular Structures of Pentameric Oligothiophenes 2020 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 9:11, s. 1100-1108 Journal article (peer-reviewed)abstract Control over the photophysical properties and molecular organization of pi-conjugated oligothiophenes is essential to their use in organic electronics. Herein we synthesized and characterized a variety of anionic pentameric oligothiophenes with different substitution patterns of L- or D-tyrosine at distinct positions along the thiophene backbone. Spectroscopic, microscopic, and theoretical studies of L- or D-tyrosine substituted pentameric oligothiophene conjugates revealed the formation of optically active pi-stacked self-assembled aggregates under acid conditions. The distinct photophysical characteristics, as well as the supramolecular structures of the assemblies, were highly influenced by the positioning of the L- or D-tyrosine moieties along the thiophene backbone. Overall, the obtained results clearly demonstrate how fundamental changes in the position of the enantiomeric side-chain functionalities greatly affect the optical properties as well as the architecture of the self-assembled supramolecular structures.
7.	Chen, Shujing, et al. (author) Manufacturing Graphene-Encapsulated Copper Particles by Chemical Vapor Deposition in a Cold Wall Reactor 2019 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 8:1, s. 58-63 Journal article (peer-reviewed)abstract Functional fillers, such as Ag, are commonly employed for effectively improving the thermal or electrical conductivity in polymer composites. However, a disadvantage of such a strategy is that the cost and performance cannot be balanced simultaneously. Therefore, the drive to find a material with both a cost efficient fabrication process and excellent performance attracts intense research interest. In this work, inspired by the core-shell structure, we developed a facile manufacturing method to prepare graphene-encapsulated Cu nanoparticles (GCPs) through utilizing an improved chemical vapor deposition (CVD) system with a cold wall reactor. The obtained GCPs could retain their spherical shape and exhibited an outstanding thermal stability up to 179 degrees C. Owing to the superior thermal conductivity of graphene and excellent oxidation resistance of GCPs, the produced GCPs are practically used in a thermally conductive adhesive (TCA), which commonly consists of Ag as the functional filler. Measurement shows a substantial 74.6 % improvement by partial replacement of Ag with GCPs.
8.	Chien, Yu-Chuan, 1990-, et al. (author) Poly(Ethylene Glycol-block-2-Ethyl-2-Oxazoline) as Cathode Binder in Lithium-Sulfur Batteries 2021 In: ChemistryOpen. - : John Wiley & Sons. - 2191-1363. ; 10:10, s. 960-965 Journal article (peer-reviewed)abstract Functional binders constitute a strategy to overcome several challenges that lithium-sulfur (Li-S) batteries are facing due to soluble reaction intermediates in the positive electrode. Poly (ethylene oxide) (PEO) and poly (vinylpyrrolidone) (PVP) are in this context a previously well-explored binder mixture. Their ether and amide groups possess affinity to the dissolved sulfur species, which enhances the sulfur utilization and mitigates the parasitic redox shuttle. However, the immiscibility of PEO and PVP is a concern for electrode stability. Copolymers comprising ether and amide groups are thus promising candidates to improve the stability the system. Here, a series of poly (ethylene glycol-block-2-ethyl-2-oxazoline) with various block lengths is synthesized and explored as binders in S/C composite electrodes in Li-S cells. While the electrochemical analyses show that although the sulfur utilization and capacity retention of the tested electrodes are similar, the integrity of the as-cast electrodes can play a key role for power capability.
9.	Deiana, Luca, 1982-, et al. (author) Direct Catalytic Asymmetric Synthesis of Pyrazolidine Derivatives 2012 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 1:3, s. 134-139 Journal article (peer-reviewed)abstract A highly enantioselective, metal-free cascade reaction between di-1,2-N-protected hydrazine and α,β-unsaturated aldehydes is disclosed. The catalytic, asymmetric cascade transformation is a direct entry to 3-hydroxypyrazolidine and 3-allylpyrazolidine derivatives in one step and two steps, respectively, with >19:1 d.r. and 98–99 % ee using simple chiral pyrrolidines as catalysts.
10.	Engen, Karin, et al. (author) Synthesis, Evaluation and Proposed Binding Pose of Substituted Spiro-Oxindole Dihydroquinazolinones as IRAP Inhibitors 2020 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 9:3, s. 325-337 Journal article (peer-reviewed)abstract Insulin‐regulated aminopeptidase (IRAP) is a new potential macromolecular target for drugs aimed for treatment of cognitive disorders. Inhibition of IRAP by angiotensin IV (Ang IV) improves the memory and learning in rats. The majority of the known IRAP inhibitors are peptidic in character and suffer from poor pharmacokinetic properties. Herein, we present a series of small non‐peptide IRAP inhibitors derived from a spiro‐oxindole dihydroquinazolinone screening hit (pIC50 5.8). The compounds were synthesized either by a simple microwave (MW)‐promoted three‐component reaction, or by a two‐step one‐pot procedure. For decoration of the oxindole ring system, rapid MW‐assisted Suzuki‐Miyaura cross‐couplings (1 min) were performed. A small improvement of potency (pIC50 6.6 for the most potent compound) and an increased solubility could be achieved. As deduced from computational modelling and MD simulations it is proposed that the S‐configuration of the spiro‐oxindole dihydroquinazolinones accounts for the inhibition of IRAP.
11.	Fontana, Carolina, et al. (author) Structural Elucidation of the O-Antigen Polysaccharide from Escherichia coli O181 2015 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 4:1, s. 47-55 Journal article (peer-reviewed)abstract Shiga-toxin-producing Escherichia coli (STEC) is an important pathogen associated to food-borne infection in humans; strains of E.coli O181, isolated from human cases of diarrhea, have been classified as belonging to this pathotype. Herein, the structure of the O-antigen polysaccharide (PS) from E.coli O181 has been investigated. The sugar analysis showed quinovosamine (QuiN), glucosamine (GlcN), galactosamine (GalN), and glucose (Glc) as major components. Analysis of the high-resolution mass spectrum of the oligosaccharide (OS), obtained by dephosphorylation of the O-deacetylated PS with aqueous 48% hydrofluoric acid, revealed a pentasaccharide composed of two QuiNAc, one GlcNAc, one GalNAc, and one Glc residue. The H-1 and (CNMR)-C-13 chemical shift assignments of the OS were carried out using 1D and 2D NMR experiments, and the OS was sequenced using a combination of tandem mass spectrometry (MS/MS) data and NMR (CNMR)-C-13 glycosylation shifts. The structure of the native PS was determined using NMR spectroscopy, and it consists of branched pentasaccharide repeating units joined by phosphodiester linkages: -> 4)[alpha-L-QuipNAc-(1 -> 3)]-alpha-D-GalpNAc6Ac-(1 -> 6)-alpha-D-Glcp-(1 -> P-4)-alpha-L-QuipNAc-(1 -> 3)-beta-D-GlcpNAc-(1 ->; the O-acetyl groups represent 0.4 equivalents per repeating unit. Both the OS and PSs exhibit rare conformational behavior since two of the five anomeric proton resonances could only be observed at an elevated temperature.
12.	Ghosh, Raju, et al. (author) Room Temperature, Metal-Free Arylation of Aliphatic Alcohols 2014 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 3:2, s. 54-57 Journal article (peer-reviewed)abstract Diaryliodonium salts are demonstrated as efficient arylating agents of aliphatic alcohols under metal-free conditions. The reaction proceeds at room temperature within 90min to give alkyl aryl ethers in good to excellent yields. Aryl groups with electron-withdrawing substituents are transferred most efficiently, and unsymmetric iodonium salts give chemoselective arylations. The methodology has been applied to the formal synthesis of butoxycaine.
13.	Gunnarsson, Anders, 1981, et al. (author) Affinity Capturing and Surface Enrichment of a Membrane Protein Embedded in a Continuous Supported Lipid Bilayer 2016 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 5:5, s. 445-449 Journal article (peer-reviewed)abstract Investigations of ligand-binding kinetics to membrane proteins are hampered by their poor stability and low expression levels, which often translates into sensitivity-related limitations impaired by low signal-to-noise ratios. Inspired by affinity capturing of water-soluble proteins, which utilizes water as the mobile phase, we demonstrate affinity capturing and local enrichment of membrane proteins by using a fluid lipid bilayer as the mobile phase. Specific membrane-protein capturing and enrichment in a microfluidic channel was accomplished by immobilizing a synthesized trivalent nitrilotriacetic acid (tris-NTA)-biotin conjugate. A polymer-supported lipid bilayer containing His(6)-tagged b-secretase (BACE) was subsequently laterally moved over the capture region by using a hydrodynamic flow. Specific enrichment of His(6)-BACE in the Ni2+-NTA-modified region of the substrate resulted in a stationary three-fold increase in surface coverage, and an accompanied increase in ligand-binding response.
14.	Isaksson, Rebecka, et al. (author) A Series of Analogues to the AT2R Prototype Antagonist C38 Allow Fine Tuning of the Previously Reported Antagonist Binding Mode 2019 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 8:1, s. 114-125 Journal article (peer-reviewed)abstract We here report on our continued studies of ligands binding tothe promising drug target angiotensin II type 2 receptor (AT2R). Two series of compounds were synthesized and investigated. The first series explored the effects of adding small substituents to the phenyl ring of the known selective nonpeptide AT2R antagonist C38, generating small but significant shifts in AT2R affinity. One compound in the first series was equipotent to C38 and showed similar kinetic solubility, and stability in both human and mouse liver microsomes. The second series was comprised of new bicyclic derivatives, amongst which one ligand exhibited a five-fold improved affinity to AT2R ascompared to C38. The majority of the compounds in the second series, including the most potent ligand, were inferior to C38 with regard to stability in both human and mouse microsomes. In contrast to our previously reported findings, ligands with shorter carbamate alkyl chains only demonstrated slightly improved stability in microsomes. Based on data presented herein, a more adequate, tentative model of the binding modes of ligand analogues to the prototype AT2R antagonist C38 is proposed, as deduced from docking redefined by molecular dynamic simulations.
15.	Jha, Vibhu, et al. (author) Binding Modes of Xanthine-Derived Selective Allosteric Site Inhibitors of MTHFD2 2023 In: Chemistryopen. - 2191-1363. ; 12:5 Journal article (peer-reviewed)abstract Methylenetetrahydrofolate dehydrogenase (MTHFD2) is a mitochondrial enzyme involved in 1 C metabolism that is upregulated in various cancer cells, but absent in normal proliferating cells. Xanthine derivatives are the first selective inhibitors of MTHFD2 which bind to its allosteric site. Xanthine derivatives (including the co-crystallized inhibitors) were herein interrogated by molecular/induced-fit docking, MM-GBSA binding free energy calculations and molecular dynamics simulations in both MTHFD2 and MTHFD1 (a close homolog expressed in healthy cells). The gained insights from our in silico protocol allowed us to study binding mode, key protein-ligand interactions and dynamic movement of the allosteric inhibitors, correlating with their experimental binding affinities, biological activities and selectivity for MTHFD2. The reported conformational changes with MTHFD2 upon binding of xanthine derivatives were furthermore evaluated and confirmed by RMSF analyses of the MD simulation trajectories. The results reported herein are expected to benefit in the rational design of selective MTHFD2 allosteric inhibitors.
16.	Kirchgeorg, Robin, et al. (author) Through-Hole, Self-Ordered Nanoporous Oxide Layers on Titanium, Niobium and Titanium–Niobium Alloys in Aqueous and Organic Nitrate Electrolytes 2012 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 1:1, s. 21-25 Journal article (peer-reviewed)
17.	Kumar, Arvind, et al. (author) Cyclopropylmethyl Protection of Phenols : Total Synthesis of the Resveratrol Dimers Anigopreissin A and Resveratrol-Piceatannol Hybrid 2018 In: ChemistryOpen. - : Wiley-VCH Verlagsgesellschaft. - 2191-1363. ; 7:12, s. 953-956 Journal article (peer-reviewed)abstract We demonstrate the versatile use of the cyclopropylmethyl group to protect phenols through the total synthesis of two benzofuran-based natural products, that is, anigopreissin A and the resveratrol-piceatannol hybrid. This protecting group is a good alternative to the conventional methyl group, owing to the feasibility of introduction, stability under a variety of conditions, and its relative ease of removal under different acidic conditions.
18.	Kumar, Saroj, et al. (author) Insights into Biochemical Alteration in Cancer-Associated Fibroblasts by using Novel Correlative Spectroscopy 2017 In: ChemistryOpen. - : WILEY-V C H VERLAG GMBH. - 2191-1363. ; 6:1, s. 149-157 Journal article (peer-reviewed)abstract The microenvironment of a tumor changes chemically and morphologically during cancer progression. Cancer-stimulated fibroblasts promote tumor growth, however, the mechanism of the transition to a cancer-stimulated fibroblast remains elusive. Here, the multi-modal spectroscopic methods Fourier transform infrared imaging (FTIRI), X-ray absorption spectroscopy (XAS) and X-ray fluorescence imaging (XFI) are used to characterize molecular and atomic alterations that occur in cancerstimulated fibroblasts. In addition to chemical changes in lipids (olefinic and acyl chain) and protein aggregation observed with FTIRI, a new infrared biomarker for oxidative stress in stimulated fibroblasts is reported. Oxidative stress is observed to cause lipid peroxidation, which leads to the appearance of a new band at 1721 cm(-1), assigned to 4-hydroxynonenal. Complementary to FTIRI, XFI is well suited to determining atom concentrations and XAS can reveal the speciation of individual elements. XFI reveals increased concentrations of P, S, K, Ca within stimulated fibroblasts. Furthermore, XAS studies reveal alterations in the speciation of S and Ca in stimulated fibroblasts, which might provide insight into the mechanisms of cancer progression. Using XFI, not only is the concentration change of individual elements observed, but also the subcellular localization. This study demonstrates the wealth of biochemical information provided by a multi-modal imaging approach and highlights new avenues for future research into the microenvironment of breast tumors.
19.	Liu, Ya, 1991, et al. (author) A Novel Graphene Quantum Dot-Based mRNA Delivery Platform 2021 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 10:7, s. 666-671 Journal article (peer-reviewed)abstract During the last decades, there has been growing interest in using therapeutic messager RNA (mRNA) together with drug delivery systems. Naked, unformulated mRNA is, however, unable to cross the cell membrane and is susceptible to degradation. Here we use graphene quantum dots (GQDs) functionalized with polyethyleneimine (PEI) as a novel mRNA delivery system. Our results show that these modified GQDs can be used to deliver intact and functional mRNA to Huh-7 hepatocarcinoma cells at low doses and, that the GQDs are not toxic, although cellular toxicity is a problem for these first-generation modified particles. Functionalized GQDs represent a potentially interesting delivery system that is easy to manufacture, stable and effective.
20.	Manojveer, Seetharaman, et al. (author) Ligand-Promoted [Pd]-Catalyzed α-Alkylation of Ketones through a Borrowing-Hydrogen Approach 2023 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 12:1 Journal article (peer-reviewed)abstract A new class of palladium complexes bearing bidentate 2-hydroxypyridine based ligands have been prepared and fully characterized. The applications of these new complexes towards ketone alkylation reactions with alcohols through a metal-ligand cooperative borrowing-hydrogen (BH) process were demonstrated.
21.	Neranon, Kitjanit, 1985-, et al. (author) Design, Synthesis and Self-Assembly of Functional Amphiphilic Metallodendrimers 2020 In: ChemistryOpen. - : John Wiley & Sons. - 2191-1363. ; 9:1, s. 45-52 Journal article (peer-reviewed)abstract A new family of alkynylated, amphiphilic dendrimers consisting of amidoamine linkers connected to 5,5 '-functionalized 2,2 '-bipyridine cores has been developed and evaluated in the formation of metallodendrimers of different generations and in self-assembly protocols. A convergent synthetic strategy was applied to provide dumbbell-shaped amphiphilic dendrimers, where the 2,2 '-bipyridine cores could be coordinated to Fe-II centers to afford corresponding metallodendrimers. The ability of the metallic- and non-metallic dendritic structures to self-assemble into functional supramolecular aggregates were furthermore evaluated in aqueous solution. Spherical aggregates with sizes of a few hundred nanometers were generally produced, where controlled disassembly of the metallodendrimers through decomplexation could be achieved.
22.	Nermark, Fiona M., et al. (author) Desulfurization of Morupule Coal with Subcritical Aqueous Ethanol Extraction 2022 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 11:11 Journal article (peer-reviewed)abstract Coal combustion greatly contributes to global emissions of toxic gases into the atmosphere, with sulfur emissions as one of the prominent pollutants in addition to carbon dioxide. Nevertheless, Botswana utilizes Morupule's sub-bituminous coal with average sulfur and ash contents, as determined in this study being 1.9 and 24.4 % by weight with an average calorific value of 22 MJ Kg−1 to generate electricity. We report an optimized extraction method for reducing total sulfur in Morupule coal from 1.9±0.2 to 0.43±0.02 wt.% at optimum conditions of ethanol/water (90/10, v/v %) at 129 °C (105 bars) in 10 minutes. A Box–Behnken experimental design was employed to select the optimal conditions of temperature (100–180 °C), water proportion in ethanol (10–90, v/v %) and extraction time (10–30 minutes), thus reducing the total sulfur under these mild conditions compared to conventional extraction. The optimized conditions were however not efficient in removing ash.
23.	Perez, Oswaldo, et al. (author) Crystal Modifications of a Cyclic Guanosine Phosphorothioate Analogue, a Drug Candidate for Retinal Neurodegenerations 2023 In: ChemistryOpen. - : John Wiley and Sons Inc. - 2191-1363. ; 12:12 Journal article (peer-reviewed)abstract In contribution to the pharmaceutical development of cyclic guanosine monophosphorothioate analogue cGMPSA as a potential active pharmaceutical ingredient (API) for the treatment of inherited retinal degenerations (IRDs), its neutral form (cGMPSA-H) and salts of sodium (-Na), calcium (-Ca), ammonium (-NH4), triethylammonium (-TEA), tris(hydroxymethyl)aminomethane (-Tris), benethamine (-Bnet), and benzathine (-BZ) were prepared. Their solid-state properties were studied with differential scanning calorimetry, thermogravimetric analysis, hot-stage microscopy, and dynamic vapor sorption, and their solubilities were measured in deionized H2O as well as aqueous HCl and NaOH buffers. A total of 21 crystal modifications of cGMPSA were found and characterized by X-ray powder diffraction. Despite their crystalline character, no API forms featured any observable melting points during thermal analyses and instead underwent exothermic decomposition at ≥163 °C. Both the vapor sorption behavior and solubility were found to differ significantly across the API forms. cGMPSA-BZ featured the lowest aqueous solubility and hygroscopicity, with 50 μg/mL and 5 % mass gain at maximum relative humidity. The synthesis and crystallization of some crystal modifications were upscaled to >10 g. Single crystal X-ray diffraction was performed which resulted in the first crystal structure determination and absolute configuration of a cyclic guanosine monophosphorothioate, confirming the RP- conformation at the phosphorus atom.
24.	Perez, Oswaldo, et al. (author) Crystal Modifications of a Cyclic Guanosine Phosphorothioate Analogue, a Drug Candidate for Retinal Neurodegenerations 2023 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 12:12 Journal article (peer-reviewed)abstract In contribution to the pharmaceutical development of cyclic guanosine monophosphorothioate analogue cGMPSA as a potential active pharmaceutical ingredient (API) for the treatment of inherited retinal degenerations (IRDs), its neutral form (cGMPSA-H) and salts of sodium (-Na), calcium (-Ca), ammonium (-NH4), triethylammonium (-TEA), tris(hydroxymethyl)aminomethane (-Tris), benethamine (-Bnet), and benzathine (-BZ) were prepared. Their solid-state properties were studied with differential scanning calorimetry, thermogravimetric analysis, hot-stage microscopy, and dynamic vapor sorption, and their solubilities were measured in deionized H2O as well as aqueous HCl and NaOH buffers. A total of 21 crystal modifications of cGMPSA were found and characterized by X-ray powder diffraction. Despite their crystalline character, no API forms featured any observable melting points during thermal analyses and instead underwent exothermic decomposition at ≥163 °C. Both the vapor sorption behavior and solubility were found to differ significantly across the API forms. cGMPSA-BZ featured the lowest aqueous solubility and hygroscopicity, with 50 μg/mL and 5 % mass gain at maximum relative humidity. The synthesis and crystallization of some crystal modifications were upscaled to >10 g. Single crystal X-ray diffraction was performed which resulted in the first crystal structure determination and absolute configuration of a cyclic guanosine monophosphorothioate, confirming the RP- conformation at the phosphorus atom.
25.	Prejanò, Mario, et al. (author) Computational Study of Mechanism and Enantioselectivity of Imine Reductase from Amycolatopsis orientalis 2022 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 11:1 Journal article (peer-reviewed)abstract Imine reductases (IREDs) are NADPH-dependent enzymes (NADPH=nicotinamide adenine dinucleotide phosphate) that catalyze the reduction of imines to amines. They exhibit high enantioselectivity for a broad range of substrates, making them of interest for biocatalytic applications. In this work, we have employed density functional theory (DFT) calculations to elucidate the reaction mechanism and the origins of enantioselectivity of IRED from Amycolatopsis orientalis. Two substrates are considered, namely 1-methyl-3,4-dihydroisoquinoline and 2-propyl-piperideine. A model of the active site is built on the basis of the available crystal structure. For both substrates, different binding modes are first evaluated, followed by calculation of the hydride transfer transition states from each complex. We have also investigated the effect of mutations of certain important active site residues (Tyr179Ala and Asn241Ala) on the enantioselectivity. The calculated energies are consistent with the experimental observations and the analysis of transition states geometries provides insights into the origins of enantioselectivity of this enzyme.
26.	Russo, Francesco, et al. (author) Optimization and Evaluation of 5-Styryl-Oxathiazol-2-one Mycobacterium tuberculosis Proteasome Inhibitors as Potential Antitubercular Agents 2015 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 4:3, s. 342-362 Journal article (peer-reviewed)abstract This is the first report of 5-styryl-oxathiazol-2-ones as inhibitors of the Mycobacterium tuberculosis (Mtb) proteasome. As part of the study, the structure-activity relationship of oxathiazolones as Mtb proteasome inhibitors has been investigated. Furthermore, the prepared compounds displayed a good selectivity profile for Mtb compared to the human proteasome. The 5-styryl-oxathiazol-2-one inhibitors identified showed little activity against replicating Mtb, but were rapidly bactericidal against nonreplicating bacteria. (E)-5-(4-Chlorostyryl)-1,3,4-oxathiazol-2-one) was most effective, reducing the colony-forming units (CFU)/mL below the detection limit in only seven days at all concentrations tested. The results suggest that this new class of Mtb proteasome inhibitors has the potential to be further developed into novel antitubercular agents for synergistic combination therapies with existing drugs.
27.	Salian, Girish D., et al. (author) Investigation of Water-Soluble Binders for LiNi0.5Mn1.5O4-Based Full Cells 2022 In: ChemistryOpen. - : John Wiley & Sons. - 2191-1363. ; 11:6 Journal article (peer-reviewed)abstract Two water-soluble binders of carboxymethyl cellulose (CMC) and sodium alginate (SA) have been studied in comparison with N-methylpyrrolidone-soluble poly(vinylidene difluoride-co-hexafluoropropylene) (PVdF-HFP) to understand their effect on the electrochemical performance of a high-voltage lithium nickel manganese oxide (LNMO) cathode. The electrochemical performance has been investigated in full cells using a Li4Ti5O12 (LTO) anode. At room temperature, LNMO cathodes prepared with aqueous binders provided a similar electrochemical performance as those prepared with PVdF-HFP. However, at 55 degrees C, the full cells containing LNMO with the aqueous binders showed higher cycling stability. The results are supported by intermittent current interruption resistance measurements, wherein the electrodes with SA showed lower resistance. The surface layer formed on the electrodes after cycling has been characterized by X-ray photoelectron spectroscopy. The amount of transition metal dissolutions was comparable for all three cells. However, the amount of hydrogen fluoride (HF) content in the electrolyte cycled at 55 degrees C is lower in the cell with the SA binder. These results suggest that use of water-soluble binders could provide a practical and more sustainable alternative to PVdF-based binders for the fabrication of LNMO electrodes.
28.	Sheng, Xiang, et al. (author) Computational Study of the Fries Rearrangement Catalyzed by Acyltransferase from Pseudomonas protegens 2024 In: ChemistryOpen. - 2191-1363. Journal article (peer-reviewed)abstract The acyltransferase from Pseudomonas protegens (PpATase) catalyzes in nature the reversible transformation of monoacetylphloroglucinol to diacetylphloroglucinol and phloroglucinol. Interestingly, this enzyme has been shown to catalyze the promiscuous transformation of 3-hydroxyphenyl acetate to 2′,4′-dihydroxyacetophenone, representing a biological version of the Fries rearrangement. In the present study, we report a mechanistic investigation of this activity of PpATase using quantum chemical calculations. A detailed mechanism is proposed, and the energy profile for the reaction is presented. The calculations show that the acylation of the enzyme is highly exothermic, while the acetyl transfer back to the substrate is only slightly exothermic. The deprotonation of the C6−H of the substrate is rate-limiting, and a remote aspartate residue (Asp137) is proposed to be the general base group in this step. Analysis of the binding energies of various acetyl acceptors shows that PpATase can promote both intramolecular and intermolecular Fries rearrangement towards diverse compounds.
29.	Stevens, Marc, 1984-, et al. (author) Synthesis of 11C-labelled Sulfonyl Carbamates via a Multicomponent Reaction Employing Sulfonyl Azides, Alcohols and [11C]CO 2016 In: ChemistryOpen. - : John Wiley & Sons. - 2191-1363. ; 5:6, s. 566-573 Journal article (peer-reviewed)abstract Herein we describe the development of new methodologyfocusing on 11C-labelling of sulfonyl carbamates in a multicomponentreaction comprising a sulfonyl azide, an alkyl alcohol and [11C]CO. Anumber of 11C-labelled sulfonyl carbamates were synthesised andisolated, and the developed methodology was then applied in thepreparation of a biologically active molecule. The target compoundwas obtained in 18±8% isolated radiochemical yield and wasevaluated for binding properties in a tumor cell assay, as well asundergoing in vivo biodistribution and imaging studies. Thisrepresents the first successful radiolabelling of C21, a non-peptideangiotensin II receptor subtype 2 agonist currently in clinical trials.
30.	Stevens, Marc Y., et al. (author) Synthesis of C-11-labeled Sulfonyl Carbamates through a Multicomponent Reaction Employing Sulfonyl Azides, Alcohols, and [C-11]CO 2016 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 5:6, s. 566-573 Journal article (peer-reviewed)abstract We describe the development of a new methodology focusing on C-11-labeling of sulfonyl carbamates in a multicomponent reaction comprised of a sulfonyl azide, an alkyl alcohol, and [C-11] CO. A number of C-11-labeled sulfonyl carbamates were synthesized and isolated, and the developed methodology was then applied in the preparation of a biologically active molecule. The target compound was obtained in 24 +/- 10% isolated radiochemical yield and was evaluated for binding properties in a tumor cell assay; in vivo biodistribution and imaging studies were also performed. This represents the first successful radiolabeling of a non-peptide angiotensin II receptor subtype 2 agonist, C21, currently in clinical trials for the treatment of idiopathic pulmonary fibrosis.
31.	Strand, Joanna, et al. (author) Site-Specific Radioiodination of HER2-Targeting Affibody Molecules using 4-Iodophenethylmaleimide Decreases Renal Uptake of Radioactivity 2015 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 4:2, s. 174-182 Journal article (peer-reviewed)abstract Affibody molecules are small scaffold-based affinity proteins with promising properties as probes for radionuclide-based molecular imaging. However, a high reabsorption of radiolabeled Affibody molecules in kidneys is an issue. We have shown that the use of I-125-3-iodo-((4-hydroxyphenyl)ethyl)maleimide (IHPEM) for site-specific labeling of cysteine-containing Affibody molecules provides high tumor uptake but low radioactivity retention in kidneys. We hypothesized that the use of 4-iodophenethylmaleimide (IPEM) would further reduce renal retention of radioactivity because of higher lipophilicity of radiometabolites. An anti-human epidermal growth factor receptor type2 (HER2) Affibody molecule (Z(HER2:2395)) was labeled using I-125-IPEM with an overall yield of 45 +/- 3%. I-125-IPEM-Z(HER2:2395) bound specifically to HER2-expressing human ovarian carcinoma cells (SKOV-3 cell line). In NMRI mice, the renal uptake of I-125-IPEM-Z(HER2:2395) (24 +/- 2 and 5.7 +/- 0.3%IAg(-1)at 1 and 4 h after injection, respectively) was significantly lower than uptake of I-125-IHPEM-Z(HER2:2395) (50 +/- 8 and 12 +/- 2%IAg(-1)at 1 and 4 h after injection, respectively). In conclusion, the use of a more lipophilic linker for the radioiodination of Affibody molecules reduces renal radioactivity.
32.	Szego, Anthony E., et al. (author) Precapture of CO2 and Hydrogenation into Methanol on Heterogenized Ruthenium and Amine-Rich Catalytic Systems 2023 In: ChemistryOpen. - 2191-1363. ; 12:6 Journal article (peer-reviewed)abstract A heterogenized alternative to the homogeneous precapture of CO2 with amines and subsequent hydrogenation to MeOH was developed using aminated silica and a Ru-MACHOTM catalyst. Commercial mesoporous silica was modified with three different amino-silane monomers and used as support for the Ru catalyst. These composites were studied by TEM and solid-state NMR spectroscopy before and after the catalytic reaction. These catalytic reactions were conducted at 155 degrees C at a H-2 and CO2 pressures of 75 and 2 bar, respectively, with the heterogeneous system (gas-solid) being probed with gas-phase infrared spectroscopy used to quantify the resulting products. High turnover number (TON) values were observed for the samples aminated with secondary amines.
33.	Sävmarker, Jonas, 1979-, et al. (author) Oxidative Heck Reactions Using Aryltrifluoroborates and Aryl N-Methyliminodiacetic Acid (MIDA) Boronates 2012 In: ChemistryOpen. - Weinheim : Wiley-VCH Verlagsgesellschaft. - 2191-1363. ; 1:3, s. 140-146 Journal article (peer-reviewed)
34.	Trejos, Alejandro, et al. (author) Development of Stereocontrolled Palladium(II)-Catalyzed Domino Heck/Suzuki β, α-Diarylation Reactions with Chelating Vinyl Ethers and Arylboronic Acids 2012 In: ChemistryOpen. - : Wiley-VCH Verlagsgesellschaft. - 2191-1363. ; 1:1, s. 49-56 Journal article (peer-reviewed)abstract A stereoselective and 1,4-benzoquinone-mediated palladium(II)-catalyzed Heck/Suzuki domino reaction involving metal coordinating cyclic methylamino vinyl ethers and a number of electronically diverse arylboronic acids has been developed and studied. Diastereomeric ratios up to 39:1 and 78% isolated yields were obtained. The stereoselectivity of the reaction was found to be highly dependent on the nature of the arylboronic acid and the amount of water present in the reaction mixture. Thus, a domino b,a-diarylation–reduction of chelating vinyl ethers can now be accomplished and stereochemically controlled, given that optimized conditions and an appropriate chiral auxiliary are used. To the best of our knowledge, this represents the first example of a stereoselective, oxidative Heck/Suzuki domino reaction in the literature.
35.	Trillo, Paz, et al. (author) Mild Reductive Functionalization of Amides into N-Sulfonylformamidines 2017 In: ChemistryOpen. - : WILEY-V C H VERLAG GMBH. - 2191-1363. ; 6:4, s. 484-487 Journal article (peer-reviewed)abstract The development of a protocol for the reductive functionalization of amides into N-sulfonylformamidines is reported. The one-pot procedure is based on a mild catalytic reduction of tertiary amides into the corresponding enamines by the use of Mo(CO)(6) (molybdenum hexacarbonyl) and TMDS (1,1,3,3-tetramethyldisiloxane). The formed enamines were allowed to react with sulfonyl azides to give the target compounds in moderate to good yields.
36.	Wang, Jun, 1983-, et al. (author) Toward Fast and Efficient Visible-Light-Driven Molecular Motors: A Minimal Design 2018 In: ChemistryOpen. - Weinheim, Germany : Wiley-VCH Verlagsgesellschaft. - 2191-1363. ; 7:8, s. 583-589 Journal article (peer-reviewed)abstract A key goal in the development of light-driven rotary molecular motors is to facilitate their usage in biology and medicine by shifting the required irradiation wavelengths from the UV regime to the nondestructive visible regime. Although some progress has been made toward this goal, most available visible-light-driven motors either have relatively low quantum yields or require that thermal steps follow the photoisomerizations that underlie the rotary motion. Here, a minimal design for visible-light-driven motors without these drawbacks is presented and evaluated on the basis of state-of-the-art quantum chemical calculations and molecular dynamics simulations. The design, featuring dihydropyridinium and cyclohexenylidene motifs and comprising only five conjugated double bonds, is found to produce a full 360° rotation through fast photoisomerizations (excited-state lifetimes of ≈ 170-250 fs) powered by photons with energies well below 3 eV.
37.	Yu, Mingjia, et al. (author) Elucidating the Binding Mode between Heparin and Inflammatory Cytokines by Molecular Modeling 2021 In: ChemistryOpen. - : John Wiley & Sons. - 2191-1363. ; 10:10, s. 966-975 Journal article (peer-reviewed)abstract Heparan sulfate (HS) interacts with a broad spectrum of inflammatory cytokines, thereby modulating their biological activities. It is believed that there is a structural-functional correlation between each protein and sugar sequences in the HS polysaccharides, however, the information in this regard is limited. In this study, we compared the binding of four inflammatory cytokines (CCL8, IL-1beta, IL-2 and IL-6) to immobilized heparin by an SPR analysis. To define the molecular base of the binding, we used a heparin pentasaccharide as representative structure to dock into the 3D-molecular structure of the cytokines. The results show a discrepancy in KD values obtained by SPR analysis and theoretical calculation, pointing to the importance to apply more than one method when describing affinity between proteins and HS. By cluster analysis of the complex formed between the pentasaccharide and cytokines, we have identified several groups in heparin forming strong hydrogen bonds with all four cytokines, which is a significant finding. This molecular and conformational information should be valuable for rational design of HS/heparin-mimetics to interfere cytokine-HS interactions.
38.	Åkerbladh, Linda, et al. (author) Synthesis of 4H-Benzo[e][1,3]oxazin-4-ones by a Carbonylation-Cyclization Domino Reaction of ortho-Halophenols and Cyanamide 2017 In: ChemistryOpen. - : Wiley. - 2191-1363. ; 6:5, s. 620-628 Journal article (peer-reviewed)abstract A mild and convenient one-step preparation of 4H-1,3-benzoxazin-4-ones by a domino carbonylation-cyclization process is developed. Readily available ortho-iodophenols are subjected to palladium-catalyzed carbonylative coupling with Mo(CO)(6) and cyanamide, followed by a spontaneous, intramolecular cyclization to afford 4H-1,3-benzaxazin-4-ones in moderate to excellent yields. Furthermore, the scope of the reaction is ex tended to include challenging orthobromophenols. Finally, to highlight the versatility of the developed method, Mo(CO), is successfully replaced with a wide array of CO-releasing reagents, such as oxalyl chloride, phenyl formate, 9-methylfluorene-9-carbonyl chloride, and formic acid, making this an appealing strategy for the synthesis of 4H-benzo[e][1,3]oxazin-4-ones.

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