jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Naresh C. Osti | Eugene Mamontov
Source: Sustainable Energy & Fuels (article, 2020-01-01)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Microscopic dynamics in room-temperature ionic liquids confined in materials for supercapacitor applications Quasielastic neutron scattering uniquely explores the mechanisms to achieve higher capacitance and rate handling in ionic liquid-based supercapacitor materials. Ionic liquid ; Supercapacitor ; Materials science ; Chemical physics ; Ionic bonding ; Dynamics (music) ; Nanotechnology ; Chemical engineering ; Engineering physics ; Chemistry ; Ion ; Physical chemistry ; Electrochemistry ; Electrode ; Physics ; Organic chemistry ; Engineering ; Acoustics Supercapacitor Materials and Fabrication ; Ionic liquids properties and applications ; Advanced battery technologies research
Authors: Aamer Saeed | Asma Khurshid | Ülrich Flörke | Gustavo A. Echeverría | Oscar E. Piro | Diego M. Gil | Mariana Rocha | Antonio Frontera | Hesham R. El‐Seedi | Amara Mumtaz | Mauricio F. Erben
Source: New Journal of Chemistry (article, 2020-01-01)
Field: Chemistry — Organic Chemistry

Intermolecular interactions in antipyrine-like derivatives 2-halo-<i>N</i>-(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1<i>H</i>-pyrazol-4-yl)benzamides: X-ray structure, Hirshfeld surface analysis and DFT calculations Based on experimental and computational data, a complex network of intermolecular interactions has been rationalized for antipyrine compounds. Chemistry ; Intermolecular force ; Halo ; Stereochemistry ; Computational chemistry ; Medicinal chemistry ; Molecule ; Organic chemistry Synthesis of heterocyclic compounds ; Phenothiazines and Benzothiazines Synthesis and Activities ; Synthesis and Characterization of Heterocyclic Compounds
Authors: Emily M. Christensen | Alexandra Bogner | Anke Vandekeere | Gabriela S. Tam | Sagar M. Patel | Donald Becker | Sarah‐Maria Fendt | John J. Tanner
Source: Journal of Biological Chemistry (article, 2020-10-28)
Field: Materials Science — Materials Chemistry

In crystallo screening for proline analog inhibitors of the proline cycle enzyme PYCR1 Pyrroline-5-carboxylate reductase 1 (PYCR1) catalyzes the biosynthetic half-reaction of the proline cycle by reducing Δ<sup>1</sup>-pyrroline-5-carboxylate (P5C) to proline through the oxidation of NAD(P)H. Many cancers alter their proline metabolism by up-regulating the proline cycle and proline biosynthesis, and knockdowns of PYCR1 lead to decreased cell proliferation. Thus, evidence is growing for PYCR1 as a potential cancer therapy target. Inhibitors of cancer targets are useful as chemical probes for studying cancer mechanisms and starting compounds for drug discovery; however, there is a notable lack of validated inhibitors for PYCR1. To fill this gap, we performed a small-scale focused screen of proline analogs using X-ray crystallography. Five inhibitors of human PYCR1 were discovered: l-tetrahydro-2-furoic acid, cyclopentanecarboxylate, l-thiazolidine-4-carboxylate, l-thiazolidine-2-carboxylate, and <i>N</i>-formyl l-proline (NFLP). The most potent inhibitor was NFLP, which had a competitive (with P5C) inhibition constant of 100 μm The structure of PYCR1 complexed with NFLP shows that inhibitor binding is accompanied by conformational changes in the active site, including the translation of an α-helix by 1 Å. These changes are unique to NFLP and enable additional hydrogen bonds with the enzyme. NFLP was also shown to phenocopy the <i>PYCR1</i> knockdown in MCF10A H-RAS<sup>V12</sup> breast cancer cells by inhibiting <i>de novo</i> proline biosynthesis and impairing spheroidal growth. In summary, we generated the first validated chemical probe of PYCR1 and demonstrated proof-of-concept for screening proline analogs to discover inhibitors of the proline cycle. Proline ; Enzyme ; Chemistry ; Biochemistry ; Amino acid Enzyme Structure and Function ; ATP Synthase and ATPases Research ; Biochemical and Molecular Research
Authors: Ruben A.G. van Eerden | Ron H.J. Mathijssen | Stijn L.W. Koolen
Source: International Journal of Nanomedicine (review, 2020-10-01)
Field: Materials Science — Biomaterials

Recent Clinical Developments of Nanomediated Drug Delivery Systems of Taxanes for the Treatment of Cancer Conventional taxanes are used as cornerstone of the chemotherapeutical treatment for a variety of malignancies. Nevertheless, a large proportion of patients do not benefit from their treatment while they do suffer from severe adverse events related to the solvent or to the active compound. Cremophor EL and polysorbate 80 free formulations, conjugates, oral formulations and different types of drug delivery systems are some examples of the several attempts to improve the treatment with taxanes. In this review article, we discuss recent clinical developments of nanomediated drug delivery systems of taxanes for the treatment of cancer. Targeting mechanisms of drug delivery systems and characteristics of the most commonly used taxane-containing drug delivery systems in the clinical setting will be discussed in this review. Drug ; Drug delivery ; Cancer ; Cancer drugs ; Medicine ; Pharmacology ; Paclitaxel ; Cancer treatment ; Nanotechnology ; Materials science ; Internal medicine Nanoparticle-Based Drug Delivery ; Nanoplatforms for cancer theranostics ; Cancer Treatment and Pharmacology
Authors: Yuriy S. Marfin | Elizaveta A. Banakova | Dmitry A. Merkushev | Sergey D. Usoltsev | Andrei V. Churakov
Source: Journal of Fluorescence (article, 2020-09-23)
Field: Materials Science — Materials Chemistry

Effects of Concentration on Aggregation of BODIPY-Based Fluorescent Dyes Solution Chemistry ; Fluorescence ; BODIPY ; Solvent polarity ; Polarity (international relations) ; Aggregation-induced emission ; Photochemistry ; Solvent ; Spectral properties ; J-aggregate ; Molecule ; Computational chemistry ; Organic chemistry ; Optics Luminescence and Fluorescent Materials ; Molecular Sensors and Ion Detection ; Porphyrin and Phthalocyanine Chemistry
Authors: Naila Al Hasan | Huilong Hou | Suchismita Sarkar | Sigurd Thienhaus | Apurva Mehta | Alfred Ludwig | Ichiro Takeuchi
Source: Engineering (article, 2020-05-15)
Field: Materials Science — Materials Chemistry

Combinatorial Synthesis and High-Throughput Characterization of Microstructure and Phase Transformation in Ni–Ti–Cu–V Quaternary Thin-Film Library Ni–Ti–based shape memory alloys (SMAs) have found widespread use in the last 70 years, but improving their functional stability remains a key quest for more robust and advanced applications. Named for their ability to retain their processed shape as a result of a reversible martensitic transformation, SMAs are highly sensitive to compositional variations. Alloying with ternary and quaternary elements to fine-tune the lattice parameters and the thermal hysteresis of an SMA, therefore, becomes a challenge in materials exploration. Combinatorial materials science allows streamlining of the synthesis process and data management from multiple characterization techniques. In this study, a composition spread of Ni–Ti–Cu–V thin-film library was synthesized by magnetron co-sputtering on a thermally oxidized Si wafer. Composition-dependent phase transformation temperature and microstructure were investigated and determined using high-throughput wavelength dispersive spectroscopy, synchrotron X-ray diffraction, and temperature-dependent resistance measurements. Of the 177 compositions in the materials library, 32 were observed to have shape memory effect, of which five had zero or near-zero thermal hysteresis. These compositions provide flexibility in the operating temperature regimes that they can be used in. A phase map for the quaternary system and correlations of functional properties are discussed with respect to the local microstructure and composition of the thin-film library. Microstructure ; Materials science ; Shape-memory alloy ; Sputter deposition ; Diffusionless transformation ; Thin film ; Ternary operation ; Thermal stability ; Characterization (materials science) ; Temperature cycling ; Hysteresis ; Wafer ; Sputtering ; Chemical engineering ; Martensite ; Thermal ; Composite material ; Nanotechnology ; Computer science ; Thermodynamics ; Condensed matter physics Shape Memory Alloy Transformations ; Transition Metal Oxide Nanomaterials
Authors: Rajendra Prasad Nandi | Pagidi Sudhakar | Kalluvettukuzhy K. Neena | Pakkirisamy Thilagar
Source: Chemistry - A European Journal (article, 2020-06-24)
Field: Materials Science — Materials Chemistry

Triarylborane‐Appended Anils and Boranils: Solid‐State Emission, Mechanofluorochromism, and Phosphorescence Herein, the design, synthesis, optical properties, and mechanofluorochromism characteristics of a series of conjugates having covalently linked triarylborane (TAB) and anil/boranil units (TAB-anil: 1 a-3 a and TAB-boranil: 1-3) are reported. The electronic interactions between TAB and anil/boranil in 1 a-3 a and 1-3 were fine-tuned by changing the boryl moiety's position on the phenyl spacer connecting the BMes<sub>2</sub> (Mes=mesityl) and anil/boranil units. A boryl moiety at the meta position (1 a) of the phenyl spacer stabilizes the enolic form (E-OH), whereas a boryl moiety at the para position (2 a and 3 a) stabilizes the keto form (Z-NH) in the solid state. However, in solution 1 a, 2 a, and 3 a exhibit keto-enol tautomerism in both ground and excited states. Compounds 1 a-3 a and 1-3 show red-shifted absorption compared with 4 a and 4, which are devoid of TAB moieties, which indicate effective participation of an empty p orbital on the boron center in 1 a-3 a and 1-3. Compounds 1 and 2 showed fluorescence variations in response to external stimuli such as mechanical grinding. Long phosphorescence lifetimes of 18-46 ms were observed for compounds 1-3. The observed optical properties of 1 a-3 a and 1-3 are rationalized in the context of quantum mechanical calculations. Phosphorescence ; Solid-state ; Photochemistry ; State (computer science) ; Materials science ; Chemistry ; Computer science ; Physics ; Optics ; Fluorescence ; Physical chemistry Luminescence and Fluorescent Materials ; Organoboron and organosilicon chemistry ; Molecular Sensors and Ion Detection
Authors: Monica J. Mendoza‐Castro | Elena Serrano | Noemi Linares | Javier García‐Martínez
Source: Advanced Materials Interfaces (article, 2020-11-12)
Field: Chemistry — Inorganic Chemistry

Surfactant‐Templated Zeolites: From Thermodynamics to Direct Observation Abstract Surfactant‐templating is a versatile method to introduce tailored intracrystalline mesoporosity in zeolites. This method has been proven to be extremely effective to finely control both the amount of mesoporosity and the size of their mesopores, while maintaining the main features of the original zeolite, such as crystallinity, acidity, and hydrothermal stability. By building on the knowledge generated during the last 30 years in the field of amorphous mesoporous materials, the surfactant‐templating method has been successfully applied to develop intracrystalline mesoporosity into a variety of zeolite structures including FAU, BEA, MOR, LTL, and MFI. The improvement in both the textural and diffusional properties of the zeolite results in excellent catalytic performances in different industrially relevant processes, ranging from fluid catalytic cracking to the synthesis of active pharmaceutical ingredients. As a result of the excellent catalytic performances shown by the surfactant‐templated mesoporous Y zeolite, this is currently being used in several refineries, being the first industrial and large‐scale application of hierarchical zeolites. In this progress report, the literature regarding the surfactant‐templating method in zeolites is critically reviewed. Zeolite ; Mesoporous material ; Materials science ; Pulmonary surfactant ; Crystallinity ; Fluid catalytic cracking ; Chemical engineering ; Hydrothermal circulation ; Catalysis ; Amorphous solid ; Nanotechnology ; Cracking ; Organic chemistry ; Composite material ; Chemistry Zeolite Catalysis and Synthesis ; Mesoporous Materials and Catalysis ; Catalysis for Biomass Conversion
Authors: Yifan Wang | Mengmeng Pan | Xu Yu | Li Xu
Source: Current Medical Science (review, 2020-06-01)
Field: Chemistry — Analytical Chemistry

The Recent Advances of Fluorescent Sensors Based on Molecularly Imprinted Fluorescent Nanoparticles for Pharmaceutical Analysis Molecularly imprinted polymer ; Fluorescence ; Nanotechnology ; Nanoparticle ; Combinatorial chemistry ; Materials science ; Chemistry ; Selectivity ; Organic chemistry ; Physics Analytical chemistry methods development ; Carbon and Quantum Dots Applications ; Electrochemical sensors and biosensors
Authors: Chenfei Li | Robert Dickson | Nils Rockstroh | Jabor Rabeah | David B. Cordes | Alexandra M. Z. Slawin | Paul Hünemörder | Anke Spannenberg | Michæl Bühl | Esteban Mejía | Eli Zysman‐Colman | Paul C. J. Kamer
Source: Catalysis Science & Technology (article, 2020-01-01)
Field: Chemistry — Organic Chemistry

Ligand electronic fine-tuning and its repercussion on the photocatalytic activity and mechanistic pathways of the copper-photocatalysed aza-Henry reaction Subtle electronic ligand effects have a strong impact on the mechanistic pathway of a photocatalytic coupling reaction. Photocatalysis ; Ligand (biochemistry) ; Catalysis ; Copper ; Chemistry ; Coupling (piping) ; Photochemistry ; Combinatorial chemistry ; Materials science ; Organic chemistry ; Receptor ; Biochemistry ; Metallurgy Radical Photochemical Reactions ; Catalytic C–H Functionalization Methods ; CO2 Reduction Techniques and Catalysts
Authors: Chaoyue Chen | Xin Wang | Ting‐Hai Yang
Source: Frontiers in Chemistry (review, 2020-09-23)
Field: Chemistry — Organic Chemistry

Recent Synthetic Applications of the Hypervalent Iodine(III) Reagents in Visible-Light-Induced Photoredox Catalysis The synergistic combination of visible-light-induced photoredox catalysis with hypervalent iodine(III) reagents (HIRs) represents a particularly important achievement in the field of hypervalent iodine chemistry, and numerous notable organic transformations were achieved in a mild and environmentally benign fashion. This account intends to summarize recent synthetic applications of HIRs in visible-light-induced photoredox catalysis, and they are organized in terms of the photochemical roles of HIRs played in reactions. Hypervalent molecule ; Photoredox catalysis ; Iodine ; Reagent ; Visible spectrum ; Photochemistry ; Catalysis ; Chemistry ; Iodine compounds ; Combinatorial chemistry ; Organic chemistry ; Materials science ; Photocatalysis ; Optoelectronics Oxidative Organic Chemistry Reactions ; Radical Photochemical Reactions ; Synthesis and Catalytic Reactions
Authors: Grace Brennan | Silvia Bergamino | Martina Pescio | Syed A. M. Tofail | Christophe Silien
Source: Nanomaterials (article, 2020-12-04)
Field: Materials Science — Biomaterials

The Effects of a Varied Gold Shell Thickness on Iron Oxide Nanoparticle Cores in Magnetic Manipulation, T1 and T2 MRI Contrasting, and Magnetic Hyperthermia Fe<sub>3</sub>O<sub>4</sub>-Au core-shell magnetic-plasmonic nanoparticles are expected to combine both magnetic and light responsivity into a single nanosystem, facilitating combined optical and magnetic-based nanotheranostic (therapeutic and diagnostic) applications, for example, photothermal therapy in conjunction with magnetic resonance imaging (MRI) imaging. To date, the effects of a plasmonic gold shell on an iron oxide nanoparticle core in magnetic-based applications remains largely unexplored. For this study, we quantified the efficacy of magnetic iron oxide cores with various gold shell thicknesses in a number of popular magnetic-based nanotheranostic applications; these included magnetic sorting and targeting (quantifying magnetic manipulability and magnetophoresis), MRI contrasting (quantifying benchtop nuclear magnetic resonance (NMR)-based T<sub>1</sub> and T<sub>2</sub> relaxivity), and magnetic hyperthermia therapy (quantifying alternating magnetic-field heating). We observed a general decrease in magnetic response and efficacy with an increase of the gold shell thickness, and herein we discuss possible reasons for this reduction. The magnetophoresis speed of iron oxide nanoparticles coated with the thickest gold shell tested here (ca. 42 nm) was only ca. 1% of the non-coated bare magnetic nanoparticle, demonstrating reduced magnetic manipulability. The T<sub>1</sub> relaxivity, r<sub>1</sub>, of the thick gold-shelled magnetic particle was ca. 22% of the purely magnetic counterpart, whereas the T<sub>2</sub> relaxivity, r<sub>2</sub>, was 42%, indicating a reduced MRI contrasting. Lastly, the magnetic hyperthermia heating efficiency (intrinsic loss power parameter) was reduced to ca. 14% for the thickest gold shell. For all applications, the efficiency decayed exponentially with increased gold shell thickness; therefore, if the primary application of the nanostructure is magnetic-based, this work suggests that it is preferable to use a thinner gold shell or higher levels of stimuli to compensate for losses associated with the addition of the gold shell. Moreover, as thinner gold shells have better magnetic properties, have previously demonstrated superior optical properties, and are more economical than thick gold shells, it can be said that "less is more". Materials science ; Magnetic resonance imaging ; Magnetic nanoparticles ; Magnetic core ; Magnetic hyperthermia ; Nanoparticle ; Colloidal gold ; Iron oxide nanoparticles ; Nuclear magnetic resonance ; Iron oxide ; Photothermal therapy ; Nanotechnology ; Metallurgy ; Electromagnetic coil Nanoparticle-Based Drug Delivery ; Characterization and Applications of Magnetic Nanoparticles ; Gold and Silver Nanoparticles Synthesis and Applications
Authors: Alessandro Parodi | Magdalena Rudzińska | Stefano Leporatti | Yuri G. Anissimov | Andrey A. Zamyatnin
Source: Frontiers in Bioengineering and Biotechnology (review, 2020-05-25)
Field: Materials Science — Materials Chemistry

Smart Nanotheranostics Responsive to Pathological Stimuli The development of nanotheranostics represents one of the most dynamic technological frontiers in the treatment of different pathological conditions. With the goal in mind to generate nanocarriers with both therapeutic and diagnostic properties, current research aims at implementing these technologies with multiple functions, including targeting, multimodal imaging, and synergistic therapies. The working mechanism of some nanotheranostics relies on physical, chemical, and biological triggers allowing for the activation of the therapeutic and/or the diagnostic properties only at the diseased site. In this review, we explored new advances in the development of smart nanotheranostics responsive to pathological stimuli, including altered pH, oxidative stress, enzymatic expression, and reactive biological molecules with a deep focus on the material used in the field to generate the particles in the context of the analyzed disease. Mechanism (biology) ; Nanocarriers ; Neuroscience ; Computer science ; Nanotechnology ; Psychology ; Materials science ; Drug delivery Nanoparticles: synthesis and applications ; Nanoplatforms for cancer theranostics ; Graphene and Nanomaterials Applications
Authors: Vera A. Vil’ | Yana A. Barsegyan | Leah Kuhn | Maria V. Ekimova | Egor A. Semenov | Аlexander А. Korlyukov | Alexander O. Terent’ev | Igor V. Alabugin
Source: Chemical Science (article, 2020-01-01)
Field: Chemistry — Organic Chemistry

Synthesis of unstrained Criegee intermediates: inverse α-effect and other protective stereoelectronic forces can stop Baeyer–Villiger rearrangement of γ-hydroperoxy-γ-peroxylactones <i>How far can we push the limits in removing stereoelectronic protection from an unstable intermediate?</i> We address this question by exploring the interplay between the primary and secondary stereoelectronic effects in the Baeyer-Villiger (BV) rearrangement by experimental and computational studies of γ-OR-substituted γ-peroxylactones, the previously elusive non-strained Criegee intermediates (CI). These new cyclic peroxides were synthesized by the peroxidation of γ-ketoesters followed by <i>in situ</i> cyclization using a BF<sub>3</sub>·Et<sub>2</sub>O/H<sub>2</sub>O<sub>2</sub> system. Although the primary effect (alignment of the migrating C-R<sub>m</sub> bond with the breaking O-O bond) is active in the 6-membered ring, weakening of the secondary effect (donation from the OR lone pair to the breaking C-R<sub>m</sub> bond) provides sufficient kinetic stabilization to allow the formation and isolation of stable γ-hydroperoxy-γ-peroxylactones with a methyl-substituent in the C6-position. Furthermore, supplementary protection is also provided by reactant stabilization originating from two new stereoelectronic factors, both identified and quantified for the first time in the present work. First, an unexpected boat preference in the γ-hydroperoxy-γ-peroxylactones weakens the primary stereoelectronic effects and introduces a ∼2 kcal mol<sup>-1</sup> Curtin-Hammett penalty for reacquiring the more reactive chair conformation. Second, activation of the secondary stereoelectronic effect in the TS comes with a ∼2-3 kcal mol<sup>-1</sup> penalty for giving up the exo-anomeric stabilization in the 6-membered Criegee intermediate. Together, the three new stereoelectronic factors (inverse α-effect, misalignment of reacting bonds in the boat conformation, and the exo-anomeric effect) illustrate the richness of stereoelectronic patterns in peroxide chemistry and provide experimentally significant kinetic stabilization to this new class of bisperoxides. Furthermore, mild reduction of γ-hydroperoxy-γ-peroxylactone with Ph<sub>3</sub>P produced an isolable γ-hydroxy-γ-peroxylactone, the first example of a structurally unencumbered CI where neither the primary nor the secondary stereoelectronic effect are impeded. Although this compound is relatively unstable, <i>it does not undergo the BV reaction</i> and instead follows a new mode of reactivity for the CI - a ring-opening process. Chemistry ; Inverse ; Computational chemistry ; Medicinal chemistry ; Stereochemistry ; Photochemistry ; Mathematics Chemical synthesis and alkaloids ; Marine Sponges and Natural Products ; Synthetic Organic Chemistry Methods