39 results match your criteria Chem[Journal]

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Developments in Photoredox/Nickel Dual-Catalyzed 1,2-Difunctionalizations.

Chem 2020 Jun;6(6):1327-1339

Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, United States.

Progress in Ni/photoredox dual catalysis has enabled the construction of C(sp)-hybridized centers under extremely mild reaction conditions in the presence of diverse functional groups. These strategies, however, are mainly restricted to the assembly of one C-C or C-heteroatom linkage because of the competitive two-component reactions and facile β-hydride elimination from alkylmetal complexes. Recently, photoinduced nickel-catalyzed 1,2-difunctionalizations of alkenes and alkynes have attracted extensive research efforts as they allow the construction of two sequential chemical bonds from inexpensive starting materials in one pot. Read More

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http://dx.doi.org/10.1016/j.chempr.2020.05.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7295134PMC

Chemistry and Biology of SARS-CoV-2.

Chem 2020 Jun 22;6(6):1283-1295. Epub 2020 May 22.

Department of Pharmacy, Drug Design Group, University of Groningen, A. Deusinglaan 1, 9713 Groningen, the Netherlands.

SARS-CoV-2 (previously 2019-nCoV or Wuhan coronavirus) caused an unprecedented fast-spreading worldwide pandemic. Although currently with a rather low mortality rate, the virus spread rapidly over the world using the modern world's traffic highways. The coronavirus (CoV) family members were responsible for several deadly outbreaks and epidemics during the last decade. Read More

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http://dx.doi.org/10.1016/j.chempr.2020.04.023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7243793PMC

A General Approach to Stereospecific Cross-Coupling Reactions of Nitrogen-Containing Stereocenters.

Chem 2020 Mar 2;6(3):781-791. Epub 2020 Mar 2.

Department of Chemistry & Biochemistry, The City College of New York, 160 Convent Ave., New York, NY 10031, USA.

A novel strategy employing cyclohexyl spectator ligands in Stille cross-coupling reactions has been developed as a general solution to the long-standing challenge of conducting stereospecific cross-coupling reactions at nitrogen-containing stereocenters. This method enables direct access to enantioenriched products that are difficult (or impossible) to obtain via alternative preparative methods. Selective and predictable transfer of a single secondary alkyl unit can be achieved under reaction conditions that exploit subtle electronic differences between activated and unactivated alkyl units. Read More

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http://dx.doi.org/10.1016/j.chempr.2020.02.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7241476PMC

Regio- and Stereoselective Rhodium(II)-Catalyzed C-H Functionalization of Cyclobutanes.

Chem 2020 Jan;6(1):304-313

Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, GA 30322.

Recent developments in controlled C-H functionalization transformations continue to inspire new retrosynthetic disconnections. One tactic in C-H functionalization is the intermolecular C-H insertion reaction of rhodium bound carbenes. These intermediates can undergo highly selective transformations through the modulation of the ligand framework of the rhodium catalyst. Read More

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http://dx.doi.org/10.1016/j.chempr.2019.12.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7233328PMC
January 2020

Synthesis of a Mechanically Planar Chiral Rotaxane Ligand for Enantioselective Catalysis.

Chem 2020 Apr 9;6(4):994-1006. Epub 2020 Apr 9.

School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, UK.

Rotaxanes are interlocked molecules in which a molecular ring is trapped on a dumbbell-shaped axle because of its inability to escape over the bulky end groups, resulting in a so-called mechanical bond. Interlocked molecules have mainly been studied as components of molecular machines, but the crowded, flexible environment created by threading one molecule through another has also been explored in catalysis and sensing. However, so far, the applications of one of the most intriguing properties of interlocked molecules, their ability to display stereogenic units that do not rely on the stereochemistry of their covalent subunits, termed "mechanical chirality," have yet to be properly explored, and prototypical demonstration of the applications of mechanically chiral rotaxanes remain scarce. Read More

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http://dx.doi.org/10.1016/j.chempr.2020.02.006DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7153771PMC

Chiral piperidines from acyclic amines via enantioselective, radical-mediated δ C-H cyanation.

Chem 2019 Dec 17;5(12):3127-3134. Epub 2019 Oct 17.

Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, United States.

Piperidines are the most prevalent heterocycle found in medicines. Yet, while they are often chiral, there remain no robust methods for their asymmetric syntheses. To solve this challenge, we have interrupted the century-old Hofmann-Löffler-Freytag (HLF) reaction to afford this privileged heterocycle. Read More

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http://dx.doi.org/10.1016/j.chempr.2019.09.010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7158869PMC
December 2019

Sterically Unprotected Nucleophilic Boron Cluster Reagents.

Chem 2019 Sep 22;5(9):2461-2469. Epub 2019 Aug 22.

Department of Chemistry and Biochemistry, University of California, Los Angeles, 609 Charles E. Young Drive East, Los Angeles, CA 90095, USA.

A cornerstone of modern synthetic chemistry rests on the ability to manipulate the reactivity of a carbon center by rendering it either electrophilic or nucleophilic. However, accessing a similar reactivity spectrum with boron-based reagents has been significantly more challenging. While classical nucleophilic carbon-based reagents normally do not require steric protection, readily accessible, unprotected boron-based nucleophiles have not yet been realized. Read More

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http://dx.doi.org/10.1016/j.chempr.2019.07.018DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7156033PMC
September 2019

Architectural Stabilization of a Gold(III) Catalyst in Metal-Organic Frameworks.

Chem 2020 Jan 25;6(1):142-152. Epub 2019 Nov 25.

Department of Chemistry, University of California, Berkeley, CA, USA.

Unimolecular decomposition pathways are challenging to address in transition-metal catalysis and have previously not been suppressed incorporation into a solid support. Two robust metal-organic frameworks (IRMOF-10 and bio-MOF-100) are used for the architectural stabilization of a structurally well-defined gold(III) catalyst. The inherent rigidity of these materials is utilized to preclude a unimolecular decomposition pathway - reductive elimination. Read More

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http://dx.doi.org/10.1016/j.chempr.2019.10.022DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7153757PMC
January 2020

Metallotexaphyrins as MRI-Active Catalytic Antioxidants for Neurodegenerative Disease: A Study on Alzheimer's Disease.

Chem 2020 Mar 12;6(3):703-724. Epub 2020 Mar 12.

Department of Chemistry, the University of Texas at Austin, Austin, TX 78712-1224, USA.

The complex etiology of neurodegeneration continues to stifle efforts to develop effective therapeutics. New agents elucidating key pathways causing neurodegeneration might serve to increase our understanding and potentially lead to improved treatments. Here, we demonstrate that a water-soluble manganese(II) texaphyrin (MMn) is a suitable magnetic resonance imaging (MRI) contrast agent for detecting larger amyloid beta constructs. Read More

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http://dx.doi.org/10.1016/j.chempr.2019.12.016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7074011PMC

Expanding the materials space of DNA via organic-phase ring-opening metathesis polymerization.

Chem 2019 Jun 22;5(6):1584-1596. Epub 2019 Apr 22.

Department of Chemistry and Chemical Biology, Northeastern University, Boston, MA 02115, United States.

Herein, we develop a facile route to bring DNA to the organic phase, which greatly expands the types of structures accessible using DNA macromonomers. Phosphotriester- and exocyclic amine-protected DNA was synthesized and further modified with a norbornene moiety, which enables homopolymerization via ring-opening metathesis to produce brush-type DNA graft polymers in high yields. Subsequent deprotection cleanly reveals the natural phosphodiester DNA. Read More

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http://dx.doi.org/10.1016/j.chempr.2019.03.023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6941852PMC

Redox-Neutral Functionalization of Aryl Boroxines via Palladium/Norbornene Cooperative Catalysis.

Chem 2019 Apr 7;5(4):929-939. Epub 2019 Mar 7.

Department of Chemistry, University of Chicago, Chicago, Illinois 60637, United States.

Palladium/norbornene (Pd/NBE) cooperative catalysis, also known as the Catellani reaction, has become an increasingly useful method for site-selective arene functionalization; however, certain constraints still exist due to its intrinsic mechanistic pathway. Herein we report a redox-neutral functionalization of aryl boroxines via Pd/NBE catalysis. An electrophile, such as carboxylic acid anhydrides or -benzoyl hydroxylamines, is coupled at the boroxine position, and a proton as the second electrophile is introduced at the position. Read More

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http://dx.doi.org/10.1016/j.chempr.2019.02.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6879102PMC

Enzyme-Instructed Peptide Assemblies Selectively Inhibit Bone Tumors.

Chem 2019 Sep 22;5(9):2442-2449. Epub 2019 Jul 22.

Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States.

Alkaline phosphatases (ALP) contribute to immunosuppression in solid tumors, but they, unfortunately, are "undruggable". Here we report enzyme-instructed assembly of peptides for selectively inhibiting the tumors that overexpress ALP. We developed a precursor with two parts; an amphiphilic, self-assembling peptides joined to a hydrophilic block (i. Read More

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http://dx.doi.org/10.1016/j.chempr.2019.06.020DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6758912PMC
September 2019

Heavy Pnictogenium Cations as Transmembrane Anion Transporters in Vesicles and Erythrocytes.

Chem 2019 Aug 15;5(8):2215-2227. Epub 2019 Jul 15.

Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States.

Our work on the complexation of fluoride anions using group 15 Lewis acids has led us to investigate the use of these main group compounds as anion transporters. In this paper, we report on the anion transport properties of tetraarylstibonium and tetraarylbismuthonium cations of the general formula [PhPnAr] with Pn = Sb or Bi and with Ar = phenyl, naphthyl, anthryl, or pyrenyl. Using EYPC-based large unilamellar vesicles, we show that these main group cations transport hydroxide, fluoride and chloride anions across phospholipid bilayers. Read More

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http://dx.doi.org/10.1016/j.chempr.2019.06.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6719792PMC

Nanoscale Metal-Organic Framework Mediates Radical Therapy to Enhance Cancer Immunotherapy.

Chem 2019 Jul 17;5(7):1892-1913. Epub 2019 Jun 17.

Department of Chemistry, The University of Chicago, Chicago, IL 60637, USA.

Checkpoint blockade immunotherapy (CBI) elicits durable therapeutic responses by blocking T cell inhibitory pathways of tumors with pre-infiltrated T cells and/or high mutational burden to activate antitumor immunity but is ineffective against poorly immunogenic tumors. Immunogenic radiotherapy, photodynamic therapy (PDT), and chemotherapy have thus been examined as immunomodulatory adjuvants to augment CBI. Dysregulated hormone production has long been linked to tumorigenesis and poor prognosis of various cancers. Read More

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http://dx.doi.org/10.1016/j.chempr.2019.05.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6681452PMC
July 2019
1 Read

An Auxiliary Approach for the Stereoselective Synthesis of Topologically Chiral Catenanes.

Chem 2019 Jun 13;5(6):1512-1520. Epub 2019 Jun 13.

School of Chemistry, University of Southampton, Highfield, Southampton SO17 1BJ, UK.

Catenanes, molecules in which two rings are threaded through one another like links in a chain, can form as two structures related like an object and its mirror image but otherwise identical if the individual rings lack bilateral symmetry. These structures are described as "topologically chiral" because, unlike most chiral molecules, it is not possible to convert one mirror-image form to the other under the rules of mathematical topology. Although intriguing and discussed as early as 1961, to date all methods of accessing molecules containing only this topological stereogenic element require the separation of the mirror-image forms via chiral stationary phase high-performance liquid chromatography, which has limited their investigation to date. Read More

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http://dx.doi.org/10.1016/j.chempr.2019.03.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6588264PMC
June 2019
1 Read

Merging Photoredox PCET with Nickel-Catalyzed Cross-Coupling: Cascade Amidoarylation of Unactivated Olefins.

Chem 2019 Feb 3;5(2):339-352. Epub 2019 Jan 3.

Roy and Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, Pennsylvania 19104-6323, United States.

The integration of amidyl radicals with cross-coupling chemistry opens new venues for reaction design. However, the lack of efficient methods for the generation of such radical species has prevented many such transformations from being brought to fruition. Herein, the amidoarylation of unactivated olefins by a cascade process from non-functionalized amides is reported by merging, for the first time, photoredox proton-coupled electron transfer (PCET) with nickel catalysis. Read More

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http://dx.doi.org/10.1016/j.chempr.2018.11.014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6508594PMC
February 2019

Site-Selective C-H Functionalization of (Hetero)Arenes via Transient, Non-Symmetric Iodanes.

Chem 2019 Feb 13;5(2):417-428. Epub 2018 Dec 13.

The Ohio State University, Department of Chemistry and Biochemistry, Columbus, OH 43210, United States.

A strategy for C-H functionalization of arenes and heteroarenes has been developed to allow site-selective incorporation of various anions, including Cl, Br, OMs, OTs, and OTf. This approach is enabled by generation of reactive, non-symmetric iodanes by combining anions and bench-stable PhI(OAc). The utility of this mechanism is demonstrated via -selective chlorination of medicinally relevant arenes, as well as site-selective C-H chlorination of heteroarenes. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S24519294183052
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http://dx.doi.org/10.1016/j.chempr.2018.11.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6481961PMC
February 2019
23 Reads

Gold-Catalyzed Oxidative Coupling of Alkynes toward the Synthesis of Cyclic Conjugated Diynes.

Chem 2018 Aug 2;4(8):1983-1993. Epub 2018 Aug 2.

Department of Chemistry, University of South Florida, Tampa, FL33620, USA.

A gold-catalyzed oxidative coupling of alkynes was developed as an efficient approach for the synthesis of challenging cyclic conjugated diynes (CCD). Compared to the classical copper-promoted oxidative coupling reaction of alkynes, this gold-catalyzed process exhibits a faster reaction rate due to the rapid reductive elimination from the Au(III) intermediate. This unique reactivity thus allowed a challenging diyne macrocyclization to take place in high efficiency. Read More

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http://dx.doi.org/10.1016/j.chempr.2018.07.004DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6429935PMC
August 2018
4 Reads

Providing a New Aniline Bioisostere through the Photochemical Production of 1-Aminonorbornanes.

Chem 2019 Jan 21;5(1):215-226. Epub 2018 Nov 21.

Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA.

This report describes the photochemical conversion of aminocyclopropanes into 1-aminonorbornanes via formal [3+2] cycloadditions initiated by homolytic fragmentation of amine radical cation intermediates. Aligning with the modern movement toward -rich motifs in drug discovery, this strategy provides access to a diverse array of substitution patterns on this saturated carbocyclic framework while offering the robust functional group tolerance (e.g. Read More

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http://dx.doi.org/10.1016/j.chempr.2018.10.017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6411061PMC
January 2019
3 Reads

Molecular Control of Internal Crystallization and Photocatalytic Function in Supramolecular Nanostructures.

Chem 2018 Jul 3;4(7):1596-1608. Epub 2018 May 3.

Department of Chemistry, Northwestern University, Evanston, IL 60208, USA.

Supramolecular light-absorbing nanostructures are useful building blocks for the design of next-generation artificial photosynthetic systems. Development of such systems requires a detailed understanding of how molecular packing influences the material's optoelectronic properties. We describe a series of crystalline supramolecular nanostructures in which the substituents on their monomeric units strongly affects morphology, ordering kinetics, and exciton behavior. Read More

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http://dx.doi.org/10.1016/j.chempr.2018.04.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6366635PMC
July 2018
2 Reads

A Massively Parallel Selection of Small Molecule-RNA Motif Binding Partners Informs Design of an Antiviral from Sequence.

Chem 2018 Oct 13;4(10):2384-2404. Epub 2018 Sep 13.

Department of Chemistry, The Scripps Research Institute, Jupiter, FL 33458, USA.

Many RNAs cause disease; however, RNA is rarely exploited as a small-molecule drug target. Our programmatic focus is to define privileged RNA motif small-molecule interactions to enable the rational design of compounds that modulate RNA biology starting from only sequence. We completed a massive, library-versus-library screen that probed over 50 million binding events between RNA motifs and small molecules. Read More

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http://dx.doi.org/10.1016/j.chempr.2018.08.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6358276PMC
October 2018
1 Read

Charge Transfer between [4Fe4S] Proteins and DNA Is Unidirectional: Implications for Biomolecular Signaling.

Chem 2019 Jan 25;5(1):122-137. Epub 2018 Oct 25.

Department of Chemistry, Duke University, Durham, NC 27708, United States.

Recent experiments suggest that DNA-mediated charge transport might enable signaling between the [4Fe4S] clusters in the C-terminal domains of human DNA primase and polymerase α, as well as the signaling between other replication and repair high-potential [4Fe4S] proteins. Our theoretical study demonstrates that the redox signaling cannot be accomplished exclusively by DNA-mediated charge transport because part of the charge transfer chain has an unfavorable free energy profile. We show that hole or excess electron transfer between a [4Fe4S] cluster and a nucleic acid duplex through a protein medium can occur within microseconds in one direction, while it is kinetically hindered in the opposite direction. Read More

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http://dx.doi.org/10.1016/j.chempr.2018.09.026DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6350243PMC
January 2019
4 Reads

Mapping Structure-Property Relationships of Organic Color Centers.

Chem 2018 Sep 19;4(9):2180-2191. Epub 2018 Jul 19.

Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA.

Organic color centers are an emergent class of quantum emitters that hold vast potential for applications in bioimaging, chemical sensing, and quantum information processing. Here, we show that these synthetic color centers follow interesting structure-property relationships through comparative spectral studies of 14 purified single-walled carbon nanotube chiralities and 30 different functional groups that vary in electron-withdrawing capability and bonding configurations. The defect emission is tunable by as much as 400 meV in the near-infrared as a function of host structure and the chemical nature of the color centers. Read More

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http://dx.doi.org/10.1016/j.chempr.2018.06.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6874404PMC
September 2018

Supramolecular Chemistry of Anionic Dimers, Trimers, Tetramers and Clusters.

Chem 2018 Jan 14;4(1):46-93. Epub 2017 Dec 14.

Center for Supramolecular Chemistry and Catalysis, Shanghai University, Shanghai 200444, China.

Two or more anions constrained in close proximity within a single pocket are found in a number of natural systems but a less common motif in artificial systems. This review summarizes work on anion receptors capable of stabilizing anionic dimers, trimers, tetramers and clusters in a well-defined fashion. These systems may provide insights into the fundamental chemistry of anion-anion interactions and provide a guide for understanding in greater detail a number of biological and environmental processes, as well as key tenants of relevance to supramolecular chemistry, extraction, transport, crystal engineering, and the like. Read More

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http://dx.doi.org/10.1016/j.chempr.2017.10.015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5881900PMC
January 2018
3 Reads

A Water-Bridged Cysteine-Cysteine Redox Regulation Mechanism in Bacterial Protein Tyrosine Phosphatases.

Chem 2017 Oct 12;3(4):665-677. Epub 2017 Oct 12.

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

The emergence of multidrug-resistant () strains highlights the need to develop more efficacious and potent drugs. However, this goal is dependent on a comprehensive understanding of virulence protein effectors at the molecular level. Here, we used a post-expression cysteine (Cys)-to-dehydrolanine (Dha) chemical editing strategy to identify a water-mediated motif that modulates accessibility of the protein tyrosine phosphatase A (PtpA) catalytic pocket. Read More

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http://dx.doi.org/10.1016/j.chempr.2017.07.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5656095PMC
October 2017
51 Reads

Bright long-lived luminescence of silicon nanocrystals sensitized by two-photon absorbing antenna.

Chem 2017 Apr;2(4):550-560

Department of Chemistry "Giacomo Ciamician", University of Bologna, Via Selmi 2, 40126 Bologna, Italy.

Silicon nanocrystals of the average diameter of 5 nm, functionalized with 4,7-di(2-thienyl)-2,1,3-benzothiadiazole chromophores () and dodecyl chains, exhibit near-infrared emission upon one-photon (1P) excitation at 515 nm and two-photon (2P) excitation at 960 nm. By using chromophores as an antenna we were able to enhance both 1P and 2P absorption cross-sections of the silicon nanocrystals to more efficiently excite their long-lived luminescence. These results chart a path to two-photon-excitable imaging probes with long-lived oxygen-independent luminescence - a rare combination of properties that should allow for a substantial increase in imaging contrast. Read More

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http://dx.doi.org/10.1016/j.chempr.2017.02.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5619661PMC
April 2017
15 Reads

Calling all hosts: Bacterial communication .

Chem 2017 Mar;2(3):334-358

Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago IL 60612, USA.

Bacteria are cosmopolitan organisms that in recent years have demonstrated many roles in maintaining host equilibrium. In this review, we discuss three roles bacteria can occupy in a host: pathogenic, symbiotic, and transient, with a specific focus on how bacterial small molecules contribute to homeostasis or dysbiosis. First, we will dissect how small molecules produced by pathogenic bacteria can be used as a source for communication during colonization and as protection against host immune responses. Read More

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http://dx.doi.org/10.1016/j.chempr.2017.02.001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5609483PMC
March 2017
2 Reads

Nanoparticle-Based Receptors Mimic Protein-Ligand Recognition.

Chem 2017 Jul 13;3(1):92-109. Epub 2017 Jul 13.

Laboratory of Molecular Modeling & Drug Discovery, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.

The self-assembly of a monolayer of ligands on the surface of noble-metal nanoparticles dictates the fundamental nanoparticle's behavior and its functionality. In this combined computational-experimental study, we analyze the structure, organization, and dynamics of functionalized coating thiols in monolayer-protected gold nanoparticles (AuNPs). We explain how functionalized coating thiols self-organize through a delicate and somehow counterintuitive balance of interactions within the monolayer itself and with the solvent. Read More

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http://dx.doi.org/10.1016/j.chempr.2017.05.016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5521955PMC
July 2017
3 Reads

Selective Surface PEGylation of UiO-66 Nanoparticles for Enhanced Stability, Cell Uptake, and pH-Responsive Drug Delivery.

Chem 2017 Apr 13;2(4):561-578. Epub 2017 Apr 13.

WestCHEM School of Chemistry, University of Glasgow, Joseph Black Building, University Avenue, Glasgow G12 8QQ, UK.

The high storage capacities and excellent biocompatibilities of metal-organic frameworks (MOFs) have made them emerging candidates as drug-delivery vectors. Incorporation of surface functionality is a route to enhanced properties, and here we report on a surface-modification procedure-click modulation-that controls their size and surface chemistry. The zirconium terephthalate MOF UiO-66 is (1) synthesized as ∼200 nm nanoparticles coated with functionalized modulators, (2) loaded with cargo, and (3) covalently surface modified with poly(ethylene glycol) (PEG) chains through mild bioconjugate reactions. Read More

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http://dx.doi.org/10.1016/j.chempr.2017.02.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5421152PMC
April 2017
58 Reads

Photochemical Perfluoroalkylation with Pyridine -Oxides: Mechanistic Insights and Performance on a Kilogram Scale.

Chem 2016 Sep;1(3):456-472

Department of Chemistry, University of Michigan, Ann Arbor, MI 48109, USA.

The direct trifluoromethylation of (hetero)arenes is a process of high importance to the pharmaceutical industry. Many reagents exist for this purpose and have found widespread use in discovery efforts; however, the step-intensive preparation of these reagents and their corresponding cost have resulted in minimal use of these methods in large-scale applications. For the ready transition of direct trifluoromethylation methodologies to large-scale application, the further development of processes utilizing inexpensive CF sources available on a metric ton scale is highly desirable. Read More

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https://linkinghub.elsevier.com/retrieve/pii/S24519294163010
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http://dx.doi.org/10.1016/j.chempr.2016.08.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5409161PMC
September 2016
29 Reads

Enzyme-Instructed Self-Assembly for Spatiotemporal Profiling of the Activities of Alkaline Phosphatases on Live Cells.

Chem 2016 Aug;1(2):246-263

Department of Chemistry, Brandeis University, Waltham, MA 02453, USA.

Alkaline phosphatase (ALP), an ectoenzyme, plays important roles in biology. But there is no activity probes for imaging ALPs in live cell environment due to the diffusion and cytotoxicity of current probes. Here we report the profiling of the activities of ALPs on live cells by enzyme-instructed self-assembly (EISA) of a D-peptidic derivative that forms fluorescent, non-diffusive nanofibrils. Read More

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http://dx.doi.org/10.1016/j.chempr.2016.07.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5380920PMC
August 2016
3 Reads

Hierarchical Self-Assembly of Halogen-Bonded Block Copolymer Complexes into Upright Cylindrical Domains.

Chem 2017 Mar 9;2(3):417-426. Epub 2017 Mar 9.

Department of Applied Physics, HYBER Centre of Excellence, Aalto University, 02150 Espoo, Finland.

Self-assembly of block copolymers into well-defined, ordered arrangements of chemically distinct domains is a reliable strategy for preparing tailored nanostructures. Microphase separation results from the system, minimizing repulsive interactions between dissimilar blocks and maximizing attractive interactions between similar blocks. Supramolecular methods have also achieved this separation by introducing small-molecule additives binding specifically to one block by noncovalent interactions. Read More

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http://dx.doi.org/10.1016/j.chempr.2017.02.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5362156PMC
March 2017
22 Reads

Beyond Media Composition: Cell Plasma Membrane Disruptions by Graphene Oxide.

Chem 2017 Mar;2(3):324-325

Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, United States.

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http://dx.doi.org/10.1016/j.chempr.2017.01.016DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6754104PMC

Synthesis of Hetero-bifunctional, End-Capped Oligo-EDOT Derivatives.

Chem 2017 Jan 12;2(1):125-138. Epub 2017 Jan 12.

Departments of Materials and Bioengineering, Institute of Biomedical Engineering, Imperial College London, London SW7 2AZ, UK.

Conjugated oligomers of 3,4-ethylenedioxythiophene (EDOT) are attractive materials for tissue engineering applications and as model systems for studying the properties of the widely used polymer poly(3,4-ethylenedioxythiophene). We report here the facile synthesis of a series of keto-acid end-capped oligo-EDOT derivatives (n = 2-7) through a combination of a glyoxylation end-capping strategy and iterative direct arylation chain extension. Importantly, these structures not only represent the longest oligo-EDOTs reported but are also bench stable, in contrast to previous reports on such oligomers. Read More

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http://dx.doi.org/10.1016/j.chempr.2016.12.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5268340PMC
January 2017
26 Reads

Graphene Oxide Nanosheets Stimulate Ruffling and Shedding of Mammalian Cell Plasma Membranes.

Chem 2016 Aug;1(2):273-286

Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, New York, 14853-1301 USA.

Graphene oxide (GO) has attracted intense interest for use in living systems and environmental applications. GO's compatibility with mammalian cells is sometimes inferred from its low cytotoxicity, but such conclusions ignore non-lethal effects that will influence GO's utility. Here we demonstrate, with rat basophilic leukemia (RBL) cells, profound plasma membrane (PM) ruffling and shedding induced by GO using confocal and live cell fluorescence microscopy, as well as scanning electron microscopy. Read More

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http://dx.doi.org/10.1016/j.chempr.2016.06.019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5120764PMC
August 2016
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Computational Screening of All Stoichiometric Inorganic Materials.

Chem 2016 Oct 13;1(4):617-627. Epub 2016 Oct 13.

Department of Chemistry, Centre for Sustainable Chemical Technologies, University of Bath, Claverton Down, Bath BA2 7AY, UK; Department of Materials Science and Engineering, Global E Institute, Yonsei University, Seoul 120-749, Korea; Department of Materials, Imperial College London, Exhibition Road, London SW7 2AZ, UK.

Forming a four-component compound from the first 103 elements of the periodic table results in more than 10 combinations. Such a materials space is intractable to high-throughput experiment or first-principle computation. We introduce a framework to address this problem and quantify how many materials can exist. Read More

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http://dx.doi.org/10.1016/j.chempr.2016.09.010DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5074417PMC
October 2016
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Immunomodulatory effects of coated gold nanoparticles in LPS-stimulated and murine model systems.

Chem 2016 11;1(2):320-327. Epub 2016 Aug 11.

Department of Chemistry, University of Massachusetts Amherst, 710 North Pleasant Street, Amherst, Massachusetts, 01003, USA.

The ability of nanoparticle surface functionalities to regulate immune responses during an immunological challenge (i. e. inflammation) would open new doors for their use in non-prophylactic therapeutics. Read More

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http://dx.doi.org/10.1016/j.chempr.2016.07.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5328597PMC
August 2016
2 Reads
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