5,364 results match your criteria Chemical science[Journal]


Solar water splitting over RhCrO-loaded AgTaO of a valence-band-controlled metal oxide photocatalyst.

Chem Sci 2020 Mar 28;11(9):2330-2334. Epub 2020 Jan 28.

Department of Applied Chemistry , Faculty of Science , Tokyo University of Science , 1-3 Kagurazaka , Shinjuku-ku , Tokyo 162-8601 , Japan . Email:

Improvement of water splitting performance of AgTaO (BG 3.4 eV) of a valence-band-controlled photocatalyst was examined. Survey of cocatalysts revealed that a RhCrO cocatalyst was much more effective than CrO, RuO, NiO and Pt for water splitting into H and O in a stoichiometric amount. Read More

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http://dx.doi.org/10.1039/c9sc05909aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069506PMC

Ligands as a universal molecular toolkit in synthesis and assembly of semiconductor nanocrystals.

Chem Sci 2020 Mar 10;11(9):2318-2329. Epub 2020 Feb 10.

Department of Chemical and Biomolecular Engineering , KAIST Institute for the Nanocentury , Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 34141 , Republic of Korea . Email:

Successful exploitation of semiconductor nanocrystals (NCs) in commercial products is due to the remarkable progress in the wet-chemical synthesis and controlled assembly of NCs. Central to the cadence of this progress is the ability to understand how NC growth and assembly can be controlled kinetically and thermodynamically. The arrested precipitation strategy offers a wide opportunity for materials selection, size uniformity, and morphology control. Read More

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http://dx.doi.org/10.1039/c9sc05200cDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069383PMC

Nanocluster growth "graft-onto": effects on geometric structures and optical properties.

Chem Sci 2020 Feb 27;11(6):1691-1697. Epub 2019 Dec 27.

Department of Chemistry and Centre for Atomic Engineering of Advanced Materials , Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials , Anhui University , Hefei , Anhui 230601 , P. R. China . Email: ; Email:

Atomically precise engineering on the nanocluster surface remains highly desirable for the fundamental understanding of how surface structures of a nanocluster contribute to its overall properties. In this paper, the concept of "graft-onto" has been exploited to facilitate nanocluster growth on surface structures. Specifically, the Ag(DPPM)Cl complex is used for re-constructing the surface structure of (SR)(PPh) ( , SR = 1-adamantanethiolate) and producing a size-growth nanocluster - (SR)(DPPM)Cl ( ). Read More

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http://dx.doi.org/10.1039/c9sc05700eDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069245PMC
February 2020

Concerted proton-electron transfer oxidation of phenols and hydrocarbons by a high-valent nickel complex.

Chem Sci 2020 Feb 6;11(6):1683-1690. Epub 2020 Jan 6.

Department of Chemistry , Yale University , New Haven , CT 06520 , USA . Email: ; Email:

The high-valent nickel(iii) complex Ni(pyalk) () was prepared by oxidation of a nickel(ii) complex, Ni(pyalk) () (pyalk = 2-pyridyl-2-propanoate). and derivatives were fully characterized by mass spectrometry and X-ray crystallography. Electron paramagnetic resonance spectroscopy and X-ray photoelectron spectroscopy confirm that the oxidation is metal-centered. Read More

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http://dx.doi.org/10.1039/c9sc05565gDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069233PMC
February 2020

Selenophosphoramide-catalyzed diamination and oxyamination of alkenes.

Chem Sci 2020 Feb 26;11(6):1677-1682. Epub 2019 Dec 26.

University of Washington , Department of Chemistry , Box 351700, Seattle , Washington 98195-1700 , USA . Email:

A new selenophosphoramide-catalyzed diamination of terminal- and -1,2-disubstituted olefins is presented. Key to the success of this transformation was the introduction of a fluoride scavenger, trimethylsilyl trifluoromethanesulfonate (TMSOTf), to prevent a competitive -elimination pathway, as was the use of a phosphoramide ligand on selenium to promote the desired substitution reaction. A screen of catalysts revealed that more electron-rich phosphine ligands resulted in higher yields of the desired product, with selenophosphoramides giving the optimal results. Read More

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http://dx.doi.org/10.1039/c9sc05335bDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069249PMC
February 2020

Direct cyclopropanation of activated N-heteroarenes site- and stereoselective dearomative reactions.

Chem Sci 2020 Feb 10;11(6):1672-1676. Epub 2020 Jan 10.

Department of Applied Chemistry , Kyung Hee University , Yongin , 17104 , Republic of Korea . Email:

A divergent cyclopropanation reaction has been accomplished the dearomative addition of sulfur ylides to activated N-heteroarenes. A series of biologically significant molecular skeletons was obtained by the direct cyclopropanation of quinolinium zwitterions. Furthermore, a straightforward synthetic route to optically enriched cyclopropane-fused heterocycles was developed using sulfur ylides as chiral nucleophiles in the 1,4-dearomative reaction. Read More

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http://dx.doi.org/10.1039/c9sc06369bDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069384PMC
February 2020

A localized molecular automaton for visualization of proteins with specific chemical modifications.

Chem Sci 2020 Feb 2;11(6):1665-1671. Epub 2020 Jan 2.

State Key Laboratory of Analytical Chemistry for Life Science , School of Chemistry and Chemical Engineering , Chemistry and Biomedicine Innovation Center (ChemBIC) , Nanjing University , Nanjing 210023 , China . Email:

Given the powerful regulation roles of chemical modification networks in protein structures and functions, it is of vital importance to acquire the spatiotemporal chemical modification pattern information in a protein-specific fashion, which is by far a highly challenging task. Herein, we design a localized DNA automaton, equipped with an - sequential propagation algorithm, for visualization of a given protein subtype with two chemical modifications of interest on the cell surface. The automaton is composed of three probes respectively for the protein and two types of modifications. Read More

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http://dx.doi.org/10.1039/c9sc04161cDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069371PMC
February 2020

Programmable adenine deamination in bacteria using a Cas9-adenine-deaminase fusion.

Chem Sci 2020 Feb 6;11(6):1657-1664. Epub 2020 Jan 6.

School of Physical Science and Technology , ShanghaiTech University , Shanghai 201210 , China . Email: ; Email:

Precise genetic manipulation is vital to studying bacterial physiology, but is difficult to achieve in some bacterial species due to the weak intrinsic homologous recombination (HR) capacity and lack of a compatible exogenous HR system. Here we report the establishment of a rapid and efficient method for directly converting adenine to guanine in bacterial genomes using the fusion of an adenine deaminase and a Cas9 nickase. The method achieves the conversion of adenine to guanine an enzymatic deamination reaction and a subsequent DNA replication process rather than HR, which is utilized in conventional bacterial genetic manipulation methods, thereby substantially simplifying the genome editing process. Read More

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http://dx.doi.org/10.1039/c9sc03784eDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069399PMC
February 2020

An intelligent ZIF-8-gated polydopamine nanoplatform for cooperatively enhanced combination phototherapy.

Chem Sci 2020 Feb 10;11(6):1649-1656. Epub 2020 Jan 10.

Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education) , College of Chemistry and Molecular Sciences , Wuhan University , Wuhan 430072 , P. R. China . Email:

The extreme complexity and heterogeneity of fatal tumors requires the development of combination phototherapy considering the limited therapeutic efficiency of conventional monomodal photodynamic therapy (PDT) or photothermal therapy (PTT). However, tumor-specific drug administration and the accompanying hypoxia-restrained PDT present the main obstacles for executing an efficient combination phototherapy. Developing a highly biocompatible, tumor-specific, near infrared absorbing, and oxygen (O)-evolving multifunctional nanoplatform is thus crucial for an effective PDT-based combination therapy. Read More

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http://dx.doi.org/10.1039/c9sc06337dDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069382PMC
February 2020

Seed-mediated evolution of hierarchical metal-organic framework quaternary superstructures.

Chem Sci 2020 Feb 3;11(6):1643-1648. Epub 2020 Jan 3.

Department of Chemistry , Texas A&M University College Station , TX 77843 , USA . Email:

The idea of hierarchy, widely observed in natural and artificial worlds, has been extensively explored in chemistry and materials science. Similar to proteins which contain primary, secondary, tertiary and quaternary structures, varying levels of hierarchy in metal-organic framework (MOF) superstructures can also be achieved. In this work, we initiate a systematic study on the morphological evolution of hierarchical superstructures with the assistance of seeded growth and explore the assembly of multiple modular MOFs into superstructures with enhanced hierarchy and diversity. Read More

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http://dx.doi.org/10.1039/c9sc06064bDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069373PMC
February 2020

Readily accessible sp-rich cyclic hydrazine frameworks exploiting nitrogen fluxionality.

Chem Sci 2020 Feb 2;11(6):1636-1642. Epub 2020 Jan 2.

Department of Chemistry , University of Warwick , Gibbet Hill Road , Coventry , CV4 7AL , UK . Email:

Increased molecular complexity correlates with improved chances of success in the drug development process. Here, a strategy for the creation of sp-rich, non-planar heterocyclic scaffolds suitable for drug discovery is described that obviates the need to generate multiple stereogenic centers with independent control. Asymmetric transfer hydrogenation using a tethered Ru-catalyst is used to efficiently produce a range of enantiopure cyclic hydrazine building blocks (up to 99% ee). Read More

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http://dx.doi.org/10.1039/c9sc04849aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069508PMC
February 2020

Development of copper-catalyzed enantioselective decarboxylative aldolization for the preparation of perfluorinated 1,3,5-triols featuring supramolecular recognition properties.

Chem Sci 2020 Feb 27;11(6):1629-1635. Epub 2019 Dec 27.

Aix Marseille Univ , CNRS , Centrale Marseille , iSm2 , Marseille , France . Email: ; http://ism2.univ-amu.fr/fr/annuaire/stereo/quintardadrien.

Fluorine is able to confer unique properties to organic molecules but the scarcity of natural organofluorine sources renders the development of new synthetic methods highly desirable. Using a chiral BOX/Cu combination, enantioselective decarboxylative aldolization of perfluorinated aldehydes has been developed. Most notably, the reaction occurring under mild conditions and with high enantiocontrol can create ketodiols in one single synthetic operation, which are precursors of crucial perfluorinated 1,3,5-triols. Read More

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http://dx.doi.org/10.1039/c9sc05196aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069514PMC
February 2020

Copper-catalyzed enantioselective arylalkynylation of alkenes.

Chem Sci 2020 Feb 8;11(6):1623-1628. Epub 2020 Jan 8.

State Key Laboratory of Organometallic Chemistry , Shanghai Institute of Organic Chemistry , Center for Excellence in Molecular Synthesis , University of Chinese Academy of Sciences , Chinese Academy of Sciences , 345 Lingling Road , Shanghai 200032 , P. R. China . Email:

A copper-catalyzed enantioselective arylalkynylation of alkenes with diaryliodonium salt and a monosubstituted alkyne is reported. The three-component coupling reactions proceed under mild reaction conditions with a broad substrate scope, leading to synthetically valuable 1,2-diaryl-3-butynes. The key to the success of this chemistry is the employment of the chiral bisoxazoline-phenylaniline (BOPA) ligand. Read More

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http://dx.doi.org/10.1039/c9sc04029cDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069229PMC
February 2020

Isomerism and dynamic behavior of bridging phosphaalkynes bound to a dicopper complex.

Chem Sci 2020 Feb 19;11(6):1607-1616. Epub 2019 Dec 19.

Department of Chemistry , University of California, Berkeley , Berkeley , CA 94720-1460 , USA . Email:

A dicopper complex featuring a symmetrically bridging nitrile ligand and supported by a binucleating naphthyridine-based ligand, [Cu( : -MeCN)DPFN](NTf), was treated with phosphaalkynes (RC[triple bond, length as m-dash]P, isoelectronic analogues of nitriles) to yield dicopper complexes that exhibit phosphaalkynes in rare : binding coordination modes. X-ray crystallography revealed that these unusual "tilted" structures exist in two isomeric forms (R "up" R "sideways"), depending on the steric profile of the phosphaalkyne's alkyl group (R = Me, Ad, or Bu). Only one isomer is observed in both solution and the solid state for R = Me (sideways) and Bu (up). Read More

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http://dx.doi.org/10.1039/c9sc05835dDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069238PMC
February 2020

Targeted cell imaging properties of a deep red luminescent iridium(iii) complex conjugated with a c-Myc signal peptide.

Chem Sci 2020 Feb 8;11(6):1599-1606. Epub 2020 Jan 8.

School of Chemistry , Cardiff University , Main Building , Cardiff , CF10 3AT , UK . Email:

A nuclear localisation sequence (NLS) peptide, PAAKRVKLD, derived from the human c-Myc regulator gene, has been functionalised with a long wavelength ( = 550 nm; = 677 nm) cyclometalated organometallic iridium(iii) complex to give the conjugate . Confocal fluorescence microscopy studies on human fibroblast cells imaged after 18-24 h incubation show that concentrations of 80-100 μM promote good cell uptake and nuclear localisation, which was confirmed though co-localisation studies using Hoechst 33342. In comparison, a structurally related, photophysically analogous iridium(iii) complex lacking the peptide sequence, , showed very different biological behaviour, with no evidence of nuclear, lysosomal or autophagic vesicle localisation and significantly increased toxicity to the cells at concentrations >10 μM that induced mitochondrial dysfunction. Read More

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http://dx.doi.org/10.1039/c9sc05568aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069228PMC
February 2020

Efficient trinuclear Ru(ii)-Re(i) supramolecular photocatalysts for CO reduction based on a new tris-chelating bridging ligand built around a central aromatic ring.

Chem Sci 2020 Feb 14;11(6):1556-1563. Epub 2019 Dec 14.

Department of Chemistry , School of Science , Tokyo Institute of Technology , 2-12-1-NE-1, O-okayama, Meguro-ku , Tokyo , 152-8550 , Japan . Email:

We have designed and synthesized a new tris-chelating polypyridine ligand () suitable to be used as a bridging ligand (BL) for constructing various supramolecular photocatalysts. This BL is a phenylene ring with three ethylene chains at 1, 3, and 5 positions, of which the other terminals are connected to 2,2'-bipyridine moieties. The ligand has been used to prepare, according to a multi-step synthetic protocol, trinuclear supramolecular photocatalysts containing different metal subunits. Read More

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http://dx.doi.org/10.1039/c9sc04532eDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069366PMC
February 2020

Combining hydrophilic and hydrophobic environment sensitive dyes to detect a wide range of cellular polarity.

Chem Sci 2020 Jan 25;11(2):596-601. Epub 2019 Nov 25.

Department of Chemistry , Department of Energy Systems Research , Ajou University , Suwon 443-749 , Korea . Email:

Intracellular polarity is an important parameter of pathological and biological phenomena of cells; abnormal polarities are associated with diabetes, neurological diseases, and cancer. However, previously reported polarity probes have issues with quantitatively detecting intracellular polarities, can measure only a limited range of polarities, and can only detect specific intracellular regions. Here, we developed a novel two-dye system, , that contains a new "turn-on" polarity probe () based on a spiropyran intramolecular ring closing-opening system activated in polar protic solvents, and a benzothiadiazole containing dye (), which emits only in non-polar solvents with a large stoke shift. Read More

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http://dx.doi.org/10.1039/c9sc04859fDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069515PMC
January 2020

Construction of a self-directed replication system for label-free and real-time sensing of repair glycosylases with zero background.

Chem Sci 2020 Jan 26;11(2):587-595. Epub 2019 Nov 26.

College of Chemistry , Chemical Engineering and Materials Science , Collaborative Innovation Center of Functionalized Probes for Chemical Imaging in Universities of Shandong , Key Laboratory of Molecular and Nano Probes , Ministry of Education , Shandong Provincial Key Laboratory of Clean Production of Fine Chemicals , Shandong Normal University , Jinan 250014 , China . Email: ; ; Tel: +86-531-86186033.

Genomic DNA damage and repair are involved in multiple fundamental biological processes, including metabolism, disease, and aging. Inspired by the natural repair mechanism , we demonstrate for the first time the construction of a self-directed replication system for label-free and real-time sensing of repair glycosylases with zero background. The presence of DNA glycosylase can catalyze the excision repair of the damaged base, successively autostarting the self-directed replication through recycling polymerization extension and strand-displacement DNA synthesis for the generation of exponentially amplified dsDNAs. Read More

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http://dx.doi.org/10.1039/c9sc04738gDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069502PMC
January 2020

Modulation of circularly polarized luminescence through excited-state symmetry breaking and interbranched exciton coupling in helical push-pull organic systems.

Chem Sci 2020 Jan 20;11(2):567-576. Epub 2019 Nov 20.

Univ Rennes , CNRS , ISCR - UMR 6226 , ScanMAT - UMS 2001 , F-35000 Rennes , France . Email: ; Email:

π-Helical push-pull dyes were prepared and their (chir)optical properties were investigated both experimentally and computationally. Specific fluorescent behaviour of bis-substituted system was observed with unprecedented solvent effect on the intensity of circularly polarized luminescence (CPL, dissymmetry factor decreasing from 10 to 10 with an increase in solvent polarity) that was linked to a change in symmetry of chiral excited state and suppression of interbranched exciton coupling. The results highlight the potential of CPL spectroscopy to study and provide a deeper understanding of electronic photophysical processes in chiral π-conjugated molecules. Read More

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http://dx.doi.org/10.1039/c9sc05231cDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069512PMC
January 2020
9.211 Impact Factor

Two-component assembly of recognition-encoded oligomers that form stable H-bonded duplexes.

Chem Sci 2020 Jan 29;11(2):561-566. Epub 2019 Nov 29.

Department of Chemistry , University of Cambridge , Lensfield Road , Cambridge CB2 1EW , UK . Email:

A new family of recognition-encoded oligomers that form stable duplexes in chloroform have been prepared. Monomer building blocks composed of dialdehydes functionalised with either a trifluoromethylphenol or phosphine oxide H-bond recognition unit were prepared. The dialdehydes were coupled with diamines by imine formation and then reduction to give homo-oligomers between one and three recognition units in length. Read More

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http://dx.doi.org/10.1039/c9sc04250dDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069511PMC
January 2020

Reduction of a dihydroboryl cation to a boryl anion and its air-stable, neutral hydroboryl radical through hydrogen shuttling.

Chem Sci 2020 Jan 25;11(2):551-555. Epub 2019 Nov 25.

Institut für Anorganische Chemie , Julius-Maximilians-Universität Würzburg , Am Hubland , 97074 Würzburg , Germany . Email:

The addition of Lewis bases to a cyclic (alkyl)(amino)carbene (CAAC)-supported dihydroboron triflate yields the mixed doubly base-stabilised dihydroboryl cations [(CAAC)BHL]. Of these, [(CAAC)BH]OTf (OTf = triflate) underwent facile two-electron reduction with KC owing to a 1,2-hydride migration from boron to the carbene carbon to yield a stable hydroboryl anion. One-electron oxidation of the latter yielded the first neutral hydroboryl radical, which is bench-stable in the solid state. Read More

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http://dx.doi.org/10.1039/c9sc05026dDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069503PMC
January 2020

A stable covalent organic framework for photocatalytic carbon dioxide reduction.

Chem Sci 2020 Jan 21;11(2):543-550. Epub 2019 Nov 21.

Department of Chemistry and Materials Innovation Factory , University of Liverpool , 51 Oxford Street , Liverpool L7 3NY , UK . Email: ; Email: ; Email:

Photocatalytic conversion of CO into fuels is an important challenge for clean energy research and has attracted considerable interest. Here we show that tethering molecular catalysts-a rhenium complex, [Re(bpy)(CO)Cl]-together in the form of a crystalline covalent organic framework (COF) affords a heterogeneous photocatalyst with a strong visible light absorption, a high CO binding affinity, and ultimately an improved catalytic performance over its homogeneous Re counterpart. The COF incorporates bipyridine sites, allowing for ligation of the Re complex, into a fully π-conjugated backbone that is chemically robust and promotes light-harvesting. Read More

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http://dx.doi.org/10.1039/c9sc03800kDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069507PMC
January 2020

Rh(ii)-catalyzed branch-selective C-H alkylation of aryl sulfonamides with vinylsilanes.

Chem Sci 2020 Jan 11;11(2):389-395. Epub 2019 Nov 11.

Department of Applied Chemistry , Faculty of Engineering , Osaka University , Suita , Osaka 565-0871 , Japan . Email:

Rhodium(ii)-catalyzed unusual branch-selective -C-H alkylation of aryl sulfonamides with vinylsilanes was achieved using an 8-aminoquinoline directing group. Notably, the -substituted aryl sulfonamides gave mono-(branched)alkylated products exclusively without the formation of any double C-H alkylated byproducts. The results of deuterium labeling experiments suggest that both hydrometalation and carbometalation pathways are involved in this conversion. Read More

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http://dx.doi.org/10.1039/c9sc04308jDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069504PMC
January 2020
9.211 Impact Factor

Shapeshifting molecules: the story so far and the shape of things to come.

Chem Sci 2020 Jan 5;11(2):324-332. Epub 2019 Dec 5.

Department of Chemistry , Durham University , Lower Mountjoy, Stockton Road , Durham , DH1 3LE , UK . Email:

Shapeshifting molecules exhibit rapid constitutional dynamics while remaining stable, isolable molecules, making them promising artificial scaffolds from which to explore complex biological systems and create new functional materials. However, their structural complexity presents challenges for designing their syntheses and understanding their equilibria. This minireview showcases (1) recent applications of highly dynamic shapeshifting molecules in sensing and distinguishing complex small molecules and (2) detailed insights into the adaptation of tractable bistable systems to changes in their local environment. Read More

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http://dx.doi.org/10.1039/c9sc05482kDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069523PMC
January 2020

Not all therapeutic antibody isotypes are equal: the case of IgM IgG in Pertuzumab and Trastuzumab.

Chem Sci 2020 Mar 12;11(10):2843-2854. Epub 2020 Feb 12.

Bioinformatics Institute (ASTAR) , 30 Biopolis Street, #07-01 Matrix , Singapore 138671 , Singapore . Email: ; Email:

The therapeutic potential of immunoglobulin M (IgM) is of considerable interest in immunotherapy due to its complement-activating and cell-agglutinating abilities. Pertuzumab and Trastuzumab are monoclonal antibodies used to treat human epidermal growth factor receptor 2 (HER2)-positive breast cancer but exhibit significantly different binding affinities as IgM when compared to its IgG isotype. Using integrative multiscale modelling and simulations of complete antibody assemblies, we show that Pertuzumab IgM is able to utilize all of its V-regions to bind multiple HER2 receptors simultaneously, while similar binding in Trastuzumab IgM is prohibited by steric clashes caused by the large globular domain of HER2. Read More

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http://dx.doi.org/10.1039/c9sc04722kDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069520PMC

Wavelength-gated photoreversible polymerization and topology control.

Chem Sci 2020 Mar 12;11(10):2834-2842. Epub 2020 Feb 12.

Centre for Materials Science , School of Chemistry and Physics , Queensland University of Technology (QUT) , 2 George Street , Brisbane , QLD 4000 , Australia . Email:

We exploit the wavelength dependence of [2 + 2] photocycloadditions and -reversions of styrylpyrene to exert unprecedented control over the photoreversible polymerization and topology of telechelic building blocks. Blue light ( = 460 nm) initiates a catalyst-free polymerization yielding high molar mass polymers ( = 60 000 g mol), which are stable at wavelengths exceeding 430 nm, yet highly responsive to shorter wavelengths. UVB irradiation ( = 330 nm) induces a rapid depolymerization affording linear oligomers, whereas violet light ( = 410 nm) generates cyclic entities. Read More

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http://dx.doi.org/10.1039/c9sc05381fDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069517PMC

Metal complexes as a promising source for new antibiotics.

Chem Sci 2020 Mar 12;11(10):2627-2639. Epub 2020 Feb 12.

Centre for Superbug Solutions , Institute for Molecular Bioscience , The University of Queensland , St. Lucia , Queensland 4072 , Australia . Email: ; Email:

There is a dire need for new antimicrobial compounds to combat the growing threat of widespread antibiotic resistance. With a currently very scarce drug pipeline, consisting mostly of derivatives of known antibiotics, new classes of antibiotics are urgently required. Metal complexes are currently in clinical development for the treatment of cancer, malaria and neurodegenerative diseases. Read More

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http://dx.doi.org/10.1039/c9sc06460eDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069370PMC
March 2020
9.211 Impact Factor

Nanomolecular singlet oxygen photosensitizers based on hemiquinonoid-resorcinarenes, the fuchsonarenes.

Chem Sci 2020 Mar 18;11(10):2614-2620. Epub 2020 Feb 18.

International Center for Materials Nanoarchitectonics , National Institute for Materials Science , Namiki 1-1 , Tsukuba , Ibaraki 305-0044 , Japan . Email:

Singlet oxygen sensitization involving a class of hemiquinonoid-substituted resorcinarenes prepared from the corresponding 3,5-di--butyl-4-hydroxyphenyl-substituted resorcinarenes is reported. Based on variation in the molecular structures, quantum yields comparable with that of the well-known photosensitizing compound -tetraphenylporphyrin were obtained for the octabenzyloxy-substituted double hemiquinonoid resorcinarene reported herein. The following classes of compounds were studied: benzyloxy-substituted resorcinarenes, acetyloxy-substituted resorcinarenes and acetyloxy-substituted pyrogallarenes. Read More

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http://dx.doi.org/10.1039/d0sc00651cDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069522PMC
March 2020
9.211 Impact Factor

The Hitchhiker's guide to biocatalysis: recent advances in the use of enzymes in organic synthesis.

Chem Sci 2020 Mar 13;11(10):2587-2605. Epub 2020 Feb 13.

Molecular Sciences Institute , School of Chemistry , University of the Witwatersrand , Johannesburg , South Africa . Email:

Enzymes are excellent catalysts that are increasingly being used in industry and academia. This perspective is primarily aimed at synthetic organic chemists with limited experience using enzymes and provides a general and practical guide to enzymes and their synthetic potential, with particular focus on recent applications. Read More

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http://dx.doi.org/10.1039/c9sc05746cDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069372PMC

Multigram-scale flow synthesis of the chiral key intermediate of (-)-paroxetine enabled by solvent-free heterogeneous organocatalysis.

Chem Sci 2019 Dec 18;10(48):11141-11146. Epub 2019 Oct 18.

Institute of Chemistry , University of Graz , NAWI Graz , Heinrichstrasse 28 , A-8010 Graz , Austria . Email:

The catalytic enantioselective synthesis of the chiral key intermediate of the antidepressant (-)-paroxetine is demonstrated as a continuous flow process on multi-gram scale. The critical step is a solvent-free organocatalytic conjugate addition followed by a telescoped reductive amination-lactamization-amide/ester reduction sequence. Due to the efficient heterogeneous catalysts and the solvent-free or highly concentrated conditions applied, the flow method offers key advances in terms of productivity and sustainability compared to earlier batch approaches. Read More

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http://dx.doi.org/10.1039/c9sc04752bDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069365PMC
December 2019

Influence of the heavy-atom effect on singlet fission: a study of platinum-bridged pentacene dimers.

Chem Sci 2019 Dec 21;10(48):11130-11140. Epub 2019 Oct 21.

Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM) , Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) , Egerlandstrasse 3 , 91058 Erlangen , Germany . Email:

The process of singlet fission (SF) produces two triplet excited states (T + T) from one singlet excited exciton (S) and a molecule in its ground state (S). It, thus, possesses the potential to boost the solar cell efficiency above the thermodynamic Shockley-Queisser limit of 33%. A key intermediate in the SF mechanism is the singlet correlated triplet pair state (TT). Read More

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http://dx.doi.org/10.1039/c9sc04410hDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069226PMC
December 2019

Pentacene derivative/DTTCNQ cocrystals: alkyl-confined mixed heterojunctions with molecular alignment and transport property tuning.

Chem Sci 2019 Dec 14;10(48):11125-11129. Epub 2019 Oct 14.

Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors , Institute of Advanced Materials (IAM) , Jiangsu National Synergetic Innovation Center for Advanced Materials , Nanjing University of Posts & Telecommunications , 9 Wenyuan Road , Nanjing 210023 , China . Email: ; Email:

Organic cocrystals are formed the self-assembly of donor and acceptor constituents, which are mixed together through weak noncovalent interactions. Although they reveal unique physical features, their synthesis still faces major drawbacks for the introduction of more potential semiconductors. Herein, we first report soluble pentacene derivative (TMTES-P) based complexes, with suitable alkyl terminal groups, enabling the location of 4,8-bis(dicyanomethylene)-4,8-dihydrobenzo[1,2-:4,5-']-dithiophene (DTTCNQ) in the crystal lattice, thereby allowing the cocrystallization of a binary system on demand. Read More

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http://dx.doi.org/10.1039/c9sc04807cDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069240PMC
December 2019
9.211 Impact Factor

A model for dinitrogen binding in the E state of nitrogenase.

Chem Sci 2019 Dec 15;10(48):11110-11124. Epub 2019 Oct 15.

Science Institute , University of Iceland , Dunhagi 3 , 107 Reykjavik , Iceland.

Molybdenum nitrogenase is one of the most intriguing metalloenzymes in nature, featuring an exotic iron-molybdenum-sulfur cofactor, FeMoco, whose mode of action remains elusive. In particular, the molecular and electronic structure of the N-binding E state is not known. In this study we present theoretical QM/MM calculations of new structural models of the E state of molybdenum-dependent nitrogenase and compare to previously suggested models for this enigmatic redox state. Read More

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http://dx.doi.org/10.1039/c9sc03610eDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069239PMC
December 2019

Strong dual emission in covalent organic frameworks induced by ESIPT.

Chem Sci 2019 Dec 16;10(48):11103-11109. Epub 2019 Oct 16.

State Key Laboratory of Medicinal Chemical Biology , Tianjin Key Laboratory of Biosensing and Molecular Recognition , College of Chemistry , Nankai University , Tianjin 300071 , P. R. China.

Here we reveal the effects of hydrogen bonds and alkyl groups on the structure and emission of covalent organic frameworks (COFs). Hydrogen bonds improve molecular rigidity leading to high crystallinity and restrict intramolecular rotation to enhance the emission of COFs. An excited-state intramolecular proton transfer (ESIPT) effect for dual emission is achieved the intramolecular hydrogen bonds between hydroxyl groups and imine bonds. Read More

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http://dx.doi.org/10.1039/c9sc03040aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069231PMC
December 2019

Structural analysis and cellular visualization of APP RNA G-quadruplex.

Chem Sci 2019 Dec 29;10(48):11095-11102. Epub 2019 Oct 29.

Department of Chemistry , City University of Hong Kong , Kowloon Tong , Hong Kong SAR , China . Email:

RNA G-quadruplexes (rG4s) are emerging structural motifs that are of pivotal importance in chemistry and biology; however, the current structural information of rG4s is limited, with their folding status and functions in cells remaining elusive. Here, we develop and employ a multi-disciplinary approach to characterize the structure, formation and function of an individual rG4 of interest and in cells. We apply this strategy to a biologically important rG4 in amyloid precursor protein (APP) transcript and reveal distinct structural features of rG4. Read More

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http://dx.doi.org/10.1039/c9sc02768hDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069244PMC
December 2019

Temperature induced valence phase transition in intermediate-valent YbPdAl.

Chem Sci 2019 Dec 29;10(48):11086-11094. Epub 2019 Oct 29.

Institut für Anorganische und Analytische Chemie , Westfälische Wilhelms-Universität Münster , Corrensstraße 30 , D-48149 Münster , Germany . Email:

A temperature induced valence phase transition from Yb at higher temperatures to Yb at lower temperatures was observed at = 110(1) K for intermetallic YbPdAl. The title compound has been prepared from the elements in sealed tantalum ampoules. The structure was refined from single-crystal data and the title compound was found to crystallize in the hexagonal YNiAl type structure with space group 6/ and lattice parameters of = 929. Read More

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http://dx.doi.org/10.1039/c9sc04437jDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069237PMC
December 2019

Direct functionalization of white phosphorus with anionic dicarbenes and mesoionic carbenes: facile access to 1,2,3-triphosphol-2-ides.

Chem Sci 2019 Dec 18;10(48):11078-11085. Epub 2019 Oct 18.

Molecular Inorganic Chemistry and Catalysis , Inorganic and Structural Chemistry , Center for Molecular Materials , Faculty of Chemistry , Universität Bielefeld , Universitätsstr. 25 , Bielefeld , D-33615 , Germany . Email: ; https://www.ghadwalgroup.de.

A series of unique CP-ring compounds [(ADC)P] (ADC = ArC{(DippN)C}; Dipp = 2,6-iPrCH; Ar = Ph , 3-MeCH, 4-MeCH, and 4-MeNCH) are readily accessible in an almost quantitative yield by the direct functionalization of white phosphorus (P) with appropriate anionic dicarbenes [Li(ADC)]. The formation of 1,2,3-triphosphol-2-ides () suggests unprecedented [3 + 1] fragmentation of P into P and P. The P cation is trapped by the (ADC) to give , while the putative P anion reacts with additional P to yield the LiP species, a useful reagent in the synthesis of organophosphorus compounds. Read More

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http://dx.doi.org/10.1039/c9sc04441hDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069227PMC
December 2019

Synthesis of montbretin A analogues yields potent competitive inhibitors of human pancreatic α-amylase.

Chem Sci 2019 Dec 18;10(48):11073-11077. Epub 2019 Oct 18.

Department of Chemistry , University of British Columbia , 2036 Main Mall , Vancouver BC , Canada V6T 1Z1 . Email:

Simplified analogues of the potent human amylase inhibitor montbretin A were synthesised and shown to bind tightly, = 60 and 70 nM, with improved specificity over medically relevant glycosidases, making them promising candidates for controlling blood glucose. Crystallographic analysis confirmed similar binding modes and identified new active site interactions. Read More

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http://dx.doi.org/10.1039/c9sc02610jDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069248PMC
December 2019

Reactivity control of a photocatalytic system by changing the light intensity.

Chem Sci 2019 Dec 30;10(48):11023-11029. Epub 2019 Oct 30.

Department of Chemistry , University of Basel , St. Johanns-Ring 19 , 4056 Basel , Switzerland . Email: ; Email:

We report a novel light-intensity dependent reactivity approach allowing us to selectively switch between triplet energy transfer and electron transfer reactions, or to regulate the redox potential available for challenging reductions. Simply by adjusting the light power density with an inexpensive lens while keeping all other parameters constant, we achieved control over one- and two-photon mechanisms, and successfully exploited our approach for lab-scale photoreactions using three substrate classes with excellent selectivities and good product yields. Specifically, our proof-of-concept study demonstrates that the irradiation intensity can be used to control (i) the available photoredox reactivity for reductive dehalogenations to selectively target either bromo- or chloro-substituted arenes, (ii) the photochemical - isomerization of olefins their photoreduction, and (iii) the competition between hydrogen atom abstraction and radical dimerization processes. Read More

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http://dx.doi.org/10.1039/c9sc04584hDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069242PMC
December 2019

The origin of the solvent dependence of fluorescence quantum yields in dipolar merocyanine dyes.

Chem Sci 2019 Dec 4;10(48):11013-11022. Epub 2019 Dec 4.

Institut für Physikalische und Theoretische Chemie , Universität Würzburg , Am Hubland , 97074 Würzburg , Germany . Email: ; Email:

Fluorophores with high quantum yields are desired for a variety of applications. Optimization of promising chromophores requires an understanding of the non-radiative decay channels that compete with the emission of photons. We synthesized a new derivative of the famous laser dye 4-dicyanomethylen-2-methyl-6--dimethylaminostyryl-4-pyran (), , merocyanine 4-(dicyanomethylene)-2--butyl-6-[3-(3-butyl-benzothiazol-2-ylidene)1-propenyl]-4-pyran (). Read More

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http://dx.doi.org/10.1039/c9sc05012dDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069518PMC
December 2019

Interconversion and reactivity of manganese silyl, silylene, and silene complexes.

Chem Sci 2019 Dec 29;10(47):10853-10869. Epub 2019 Oct 29.

Department of Chemistry , McMaster University , 1280 Main Street West , Hamilton , Ontario L8S 4M1 , Canada . Email:

Manganese disilyl hydride complexes [(dmpe)MnH(SiHR)] ( : R = Ph, : R = Bu) reacted with ethylene to form silene hydride complexes [(dmpe)MnH(RHSi[double bond, length as m-dash]CHMe)] ( : R = Ph, : R = Bu). Compounds reacted with a second equivalent of ethylene to generate [(dmpe)MnH(REtSi[double bond, length as m-dash]CHMe)] ( : R = Ph, : R = Bu), resulting from apparent ethylene insertion into the silene Si-H bond. Furthermore, in the absence of ethylene, silene complex slowly isomerized to the silylene hydride complex [(dmpe)MnH([double bond, length as m-dash]SiEt Bu)] ( ). Read More

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http://dx.doi.org/10.1039/c9sc04513aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069235PMC
December 2019

Blue thermally activated delayed fluorescence emitters incorporating acridan analogues with heavy group 14 elements for high-efficiency doped and non-doped OLEDs.

Chem Sci 2019 Dec 29;10(46):10687-10697. Epub 2019 Oct 29.

INAMORI Frontier Research Center (IFRC) , Kyushu University , 744 Motooka, Nishi-ku , Fukuoka 819-0395 , Japan . Email:

Deep-blue thermally activated delayed fluorescence (TADF) emitters are promising alternatives for conventional fluorescence and phosphorescence materials for practical application in organic light-emitting diodes (OLEDs). However, as appropriate bipolar hosts for deep-blue TADF-OLEDs are scarce, the development of efficient deep-blue TADF emitters that are applicable to both doped and non-doped systems is an urgent task. In this study, we developed a new family of blue TADF emitters that demonstrated high photoluminescence (PL) and electroluminescence (EL) quantum efficiencies in both doped and non-doped (neat) systems. Read More

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http://dx.doi.org/10.1039/c9sc04492bDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069243PMC
December 2019

Thinking outside the "Blue Box": from molecular to supramolecular pH-responsiveness.

Chem Sci 2019 Dec 23;10(46):10680-10686. Epub 2019 Oct 23.

Departamento de Química , Centro de Investigacións Científicas Avanzadas (CICA) , Facultad de Ciencias , Universidade da Coruña , 15071 , A Coruña , Spain . Email: ; Email:

We present herein the development of a new polycationic cyclophane: the "red box", second in a series of hydrazone-based analogues of the well-known organic receptor cyclobis(paraquat--phenylene)cyclophane ("blue box"). The macrocycle has been prepared in an excellent yield in aqueous media, and shows both a remarkable pH-responsiveness and unusual hydrolytic stability of the two hydrazone C[double bond, length as m-dash]N bonds, associated with charge delocalization of the amine lone pair. Whilst in aqueous media the "red box" is able to complex a variety of aromatic substrates, both in its acidic and basic form, in organic media the cyclophane is only able to capture those in the acidic form, resulting in supramolecular pH-responsiveness. Read More

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http://dx.doi.org/10.1039/c9sc04489bDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069232PMC
December 2019

Correction: Enantioselective total synthesis of the unnatural enantiomer of quinine.

Chem Sci 2019 Nov 31;10(44):10445. Epub 2019 Oct 31.

Department of Chemistry , Graduate School of Science and Technology , Kumamoto University , 2-39-1, Kurokami, Chuo-ku , Kumamoto 860-8555 , Japan . Email:

[This corrects the article DOI: 10.1039/C9SC03879E.]. Read More

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http://dx.doi.org/10.1039/c9sc90226kDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069521PMC
November 2019

A photochromic upconversion nanoarchitecture: towards activatable bioimaging and dual NIR light-programmed singlet oxygen generation.

Chem Sci 2019 Nov 18;10(44):10231-10239. Epub 2019 Oct 18.

CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety , CAS Center for Excellence in Nanoscience , National Center for Nanoscience and Technology , Beijing 100190 , China . Email: ; Email:

The precise control of singlet oxygen (O) generation is in great demand for biological studies and precision medicine. Here, a nanoarchitecture is designed and synthesized for generating O in a dual NIR light-programmable manner, while shifting to the therapeutic window. The nanoarchitecture is constructed by controlled synthesis of mesoporous silica-coated upconversion nanoparticles (UCNPs), wherein the porphyrin photosensitizers (PSs) are covalently embedded inside the silica walls while NIR (808 nm)-responsive diarylethene (DAE) photochromic switches are loaded in the nanopores. Read More

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http://dx.doi.org/10.1039/c9sc03524aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069247PMC
November 2019

Improving MOF stability: approaches and applications.

Chem Sci 2019 Nov 2;10(44):10209-10230. Epub 2019 Oct 2.

Hefei National Laboratory for Physical Sciences at the Microscale , CAS Key Laboratory of Soft Matter Chemistry , Collaborative Innovation Center of Suzhou Nano Science and Technology , Department of Chemistry , University of Science and Technology of China , Hefei , Anhui 230026 , P. R. China . Email:

Metal-organic frameworks (MOFs) have been recognized as one of the most important classes of porous materials due to their unique attributes and chemical versatility. Unfortunately, some MOFs suffer from the drawback of relatively poor stability, which would limit their practical applications. In the recent past, great efforts have been invested in developing strategies to improve the stability of MOFs. Read More

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http://dx.doi.org/10.1039/c9sc03916cDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7069376PMC
November 2019

Identification and structural insight of an effective PPARγ modulator with improved therapeutic index for anti-diabetic drug discovery.

Chem Sci 2020 Feb 21;11(8):2260-2268. Epub 2020 Jan 21.

Guangzhou Municipal and Guangdong Provincial Key Laboratory of Protein Modification and Degradation & Molecular Target and Clinical Pharmacology , State Key Laboratory of Respiratory Disease , School of Pharmaceutical Sciences & the Fifth Affiliated Hospital , Guangzhou Medical University , Guangzhou , Guangdong 511436 , China . Email:

Peroxisome proliferator-activated receptor γ (PPARγ) is a key regulator of glucose homeostasis and lipid metabolism, and an important target for the development of modern anti-diabetic drugs. However, current PPARγ-targeting anti-diabetic drugs such as classical thiazolidinediones (TZDs) are associated with undesirable side effects. To address this concern, we here describe the structure-based design, synthesis, identification and detailed and characterization of a novel, decanoic acid (DA)-based and selective PPARγ modulator (SPPARγM), VSP-77, especially (S)-VSP-77, as the potential "hit" for the development of improved and safer anti-diabetic therapeutics. Read More

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http://dx.doi.org/10.1039/c9sc05487aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7059199PMC
February 2020

Tipping the balance: theoretical interrogation of divergent extended heterolytic fragmentations.

Chem Sci 2020 Feb 9;11(8):2231-2242. Epub 2020 Jan 9.

Department of Chemistry , University of California , Davis , CA 95616 , USA . Email:

Herein we interrogate a type of heterolytic fragmentation reaction called a 'divergent fragmentation' using density functional theory (DFT), natural bond orbital (NBO) analysis, molecular dynamics (AIMD), and external electric field (EEF) calculations. We demonstrate that substituents, electrostatic environment and non-statistical dynamic effects all influence product selectivity in reactions that involve divergent fragmentation pathways. Direct dynamics simulations reveal an unexpected post-transition state bifurcation (PTSB), and EEF calculations suggest that some transition states for divergent pathways can, in principle, be selectively stabilized if an electric field of the correct magnitude is oriented appropriately. Read More

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http://dx.doi.org/10.1039/c9sc05161aDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7059201PMC
February 2020

Rational selection of co-catalysts for the deaminative hydrogenation of amides.

Chem Sci 2020 Feb 20;11(8):2225-2230. Epub 2020 Jan 20.

Hylleraas Centre for Quantum Molecular Sciences , Department of Chemistry , University of Oslo , P. O. Box 1033, Blindern , N-0315 Oslo , Norway . Email:

The catalytic hydrogenation of amides is an atom economical method to synthesize amines. Previously, it was serendipitously discovered that the combination of a secondary amide co-catalyst with (PNP)Fe(H)(CO) (PNP = N[CHCH(PPr)]), results in a highly active base metal system for deaminative amide hydrogenation. Here, we use DFT to develop an improved co-catalyst for amide hydrogenation. Read More

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http://dx.doi.org/10.1039/c9sc03812dDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7059200PMC
February 2020

Overcoming the difficulties of predicting conformational polymorph energetics in molecular crystals correlated wavefunction methods.

Chem Sci 2020 Feb 14;11(8):2200-2214. Epub 2020 Jan 14.

Department of Chemistry , University of California , Riverside , California 92521 , USA . Email: ; Tel: +1-951-827-7869.

Molecular crystal structure prediction is increasingly being applied to study the solid form landscapes of larger, more flexible pharmaceutical molecules. Despite many successes in crystal structure prediction, van der Waals-inclusive density functional theory (DFT) methods exhibit serious failures predicting the polymorph stabilities for a number of systems exhibiting conformational polymorphism, where changes in intramolecular conformation lead to different intermolecular crystal packings. Here, the stabilities of the conformational polymorphs of -acetamidobenzamide, ROY, and oxalyl dihydrazide are examined in detail. Read More

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http://dx.doi.org/10.1039/c9sc05689kDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7059316PMC
February 2020