A5070593331- Catalytic Alkyne Reactions
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Cyclopropane Reaction Mechanisms
- Catalytic C–H Functionalization Methods
- Asymmetric Hydrogenation and Catalysis
- Molecular Junctions and Nanostructures
- Synthetic Organic Chemistry Methods
- Oxidative Organic Chemistry Reactions
- Quantum Dots Synthesis And Properties
- Advanced biosensing and bioanalysis techniques
- Enzyme function and inhibition
- Microfluidic and Capillary Electrophoresis Applications
- Semiconductor materials and devices
- Nanomaterials for catalytic reactions
- Ga2O3 and related materials
- Hepatitis C virus research
- Hepatitis B Virus Studies
- Spectroscopy and Quantum Chemical Studies
- Enzyme Catalysis and Immobilization
- Ionic liquids properties and applications
- Liver Disease Diagnosis and Treatment
- Sulfur-Based Synthesis Techniques
- Microfluidic and Bio-sensing Technologies
- Asymmetric Synthesis and Catalysis
Gilead Sciences (United States)
2024
University of California, Berkeley
2007-2015
Mallinckrodt (United States)
2014
Harvard University
2011-2014
Harvard University Press
2014
A series of gold(I)-catalyzed rearrangement reactions alkynyl sulfoxides are reported. Homopropargylsulfoxides rearranged to benzothiepinones or benzothiopines, while α-thioenones formed in the reaction propargylsulfoxides. The proposed mechanism proceeds via an α-carbonyl gold−carbenoid intermediate through gold-promoted oxygen atom transfer from sulfoxide alkyne.
A series of gold(I)-catalyzed oxidative rearrangement reactions alkynes using sulfoxides as stoichiometric oxidants are reported. The postulated to proceed through intermolecular oxygen atom transfer from the sulfoxide gold(I)−carbenoid intermediates. Under conditions for rearrangement, 1,6-enynes isomerized cyclopropyl aldehydes, homopropargyl azides produce pyrrolones, acetylenic α-diazoketones form cyclic en-1,4-diones, and propargylesters 2-acyloxyenals.
A convenient gold(III)-catalyzed synthesis of azepines from the intermolecular annulation propargyl esters and α,β-unsaturated imines is reported (19 examples, 55−95% yield). This formal [4 + 3]-cycloaddition reaction proposed to proceed via a stepwise process involving intramolecular trapping an allyl−gold intermediate.
The gold-catalyzed [3+3]-cycloaddition reaction of propargyl esters and azomethine imines has been developed. provides a rapid entry into wide range substituted tetrahydropyridazine derivatives from simple starting materials. A stepwise mechanism involving addition the 1,3-dipole to gold-carbenoid intermediate is proposed.
The chemical community has recently witnessed a dramatic increase in the application of cationic gold(I)-phosphine complexes as homogeneous catalysts for organic synthesis. majority gold(I)-catalyzed reactions rely on nucleophilic additions to carbon–carbon multiple bonds, which have been activated by coordination gold(I) catalyst. However, structural evidence alkynes limited. Here, we report crystal structure η 2 -coordinated alkyne. Related Ag(I) and Cu(I) synthesized comparison....
Approaches to research in organic chemistry are as numerous the reactions they describe. In this account, we describe our reactivity-based approach. Using work area of gold catalysis a background, discuss how focus on reaction mechanism and reactivity paradigms can lead rapid discovery new synthetic tools.
The liquid–metal eutectic of gallium and indium (EGaIn) is a useful electrode for making soft electrical contacts to self-assembled monolayers (SAMs). This has, however, one feature whose effect on charge transport has been incompletely understood: thin (approximately 0.7 nm) film—consisting primarily Ga2O3—that covers its surface when in contact with air. SAMs that rectify current have measured using this AgTS-SAM//Ga2O3/EGaIn (where AgTS = template-stripped Ag surface) junctions. paper...
This Communication demonstrates the generation of over 300 phase-separated systems-ranging from two to six phases-from mixtures aqueous solutions polymers and surfactants. These multiphase systems (MuPSs) form self-assembling, thermodynamically stable step-gradients in density using a common solvent, water. The steps between phases MuPS can be very small (Δρ ≈ 0.001 g/cm(3)), do not change time, tuned by addition co-solutes. We use sets similar objects, glass beads pellets different...
Insensitivity: A series of molecules containing a common head group and body as well structurally varied tail groups (-R) has been used in junctions with the structure Ag/S(CH2)4CONH(CH2)2R//Ga2O3/EGaIn to study rates charge transport by tunneling. Changing R over range aliphatic, aromatic, heteroaromatic organic was found not significantly influence rate tunneling (see plots; dashed lines represent calibration standards).
Paramagnetic ionic liquids (PILs) provide new capabilities to measurements of density using magnetic levitation (MagLev). In a typical measurement, diamagnetic object unknown is placed in container containing PIL. The between two magnets (typically NdFeB, oriented with like poles facing). the can be determined by measuring its position field along vertical axis (levitation height, h), either as an absolute value or relative internal standards known density. For MagLev, PILs have three...
This paper describes the use of magnetic levitation (MagLev) to measure association proteins and ligands. The method starts with diamagnetic gel beads that are functionalized covalently small molecules (putative ligands). Binding protein ligands within bead causes a change in density bead. When these suspended paramagnetic aqueous buffer placed between poles two NbFeB magnets like facing, changes on binding result height can be used quantify amount bound. uses reaction–diffusion model...
This paper describes a method based on magnetic levitation (MagLev) that is capable of indirectly measuring the binding unlabeled ligands to protein. We demonstrate this by affinity bovine carbonic anhydrase (BCA) for variety (most which are benzene sulfonamide derivatives). utilizes porous gel beads functionalized with common aryl ligand. The incubated BCA and allowed reach an equilibrium state in majority immobilized bound BCA. Since less dense than protein, protein bead increases overall...
This paper reports the development of Metal-amplified Density Assays, or MADAs - a method conducting quantitative multiplexed assays, including immunoassays, by using Magnetic Levitation (MagLev) to measure metal-amplified changes in density beads labeled with biomolecules. The binding target analytes (i.e. proteins, antibodies, antigens) complementary ligands immobilized on surface beads, followed chemical amplification form that results change (achieved gold nanoparticle-labeled...
This paper describes a method for the selective precipitation and purification of monovalent protein (carbonic anhydrase is used as demonstration) from cellular lysate using ammonium sulfate oligovalent ligands. The ligands induce formation protein–ligand aggregates, at an appropriate concentration dissolved sulfate, these complexes precipitate. involves three steps: (i) removal high-molecular-weight impurities through addition to crude cell lysate; (ii) introduction ligand target aggregates...
Unempfindlich: Eine Serie von Molekülen mit gleicher Kopfgruppe und Kohlenstoffkette, aber unterschiedlichen Endgruppen R wurde in Kontakten vom Typ Ag/S(CH2)4CONH(CH2)2R//Ga2O3/EGaIn eingesetzt (siehe Bild), um die Geschwindigkeit des Ladungstransports durch Tunneln zu studieren. Ein Variieren zwischen aliphatischen, aromatischen heteroaromatischen hatte keinen signifikanten Einfluss auf Tunnelgeschwindigkeit. Detailed facts of importance to specialist readers are published as ”Supporting...
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at glance that was extracted from about 100 leading journals. To access of an article which published elsewhere, please select “Full Text” option. The original trackable via the “References”
ChemInform is a weekly Abstracting Service, delivering concise information at glance that was extracted from about 200 leading journals. To access Abstract, please click on HTML or PDF.
Chronic hepatitis B (CHB) virus infection afflicts hundreds of millions people and causes nearly one million deaths annually. The high levels circulating viral surface antigen (HBsAg) that characterize CHB may lead to T-cell exhaustion, resulting in an impaired antiviral immune response the host. Agents suppress HBsAg could help invigorate immunity toward infected hepatocytes facilitate a functional cure. A series dihydropyridoisoquinolizinone (DHQ) inhibitors human poly(A) polymerases...
Abstract A stepwise migration/fragmentation of acetals or ketals gives gold‐carbenoid intermediates which undergo asymmetric [3 + 2] cycloaddition with aldehydes to form 2,5‐dihydrofurans.