A5027743970- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Molecular spectroscopy and chirality
- Crystallography and molecular interactions
- Machine Learning in Materials Science
- Computational Drug Discovery Methods
- Various Chemistry Research Topics
- Plant biochemistry and biosynthesis
- Spectroscopy and Quantum Chemical Studies
- Natural product bioactivities and synthesis
- Catalytic C–H Functionalization Methods
- Protein Structure and Dynamics
- Chemical Synthesis and Analysis
- Asymmetric Hydrogenation and Catalysis
- Microbial Natural Products and Biosynthesis
- History and advancements in chemistry
- Historical Studies and Socio-cultural Analysis
- Bacteriophages and microbial interactions
- Mosquito-borne diseases and control
- Chemical Reaction Mechanisms
- French Historical and Cultural Studies
- Cyclopropane Reaction Mechanisms
- Analytical Chemistry and Chromatography
- Virology and Viral Diseases
- Synthesis and Catalytic Reactions
Healthwise
2022-2024
University of California, Davis
2015-2022
University of Washington
2022
University of Bristol
2019-2020
Total (France)
2006
Clínica Sagrada Esperança
2006
Abstract The existence of post-transition state bifurcations on potential energy surfaces for organic and biological reaction mechanisms has been known decades, but recently, new reports have occurring at a much higher rate. Beyond simply discovering bifurcations, computational chemists are developing techniques to understand what aspects molecular structure vibrations control the product selectivity in systems containing bifurcations. For example, distribution products seen simulations...
High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand libraries can access far greater space, provided that the predictive accuracy sufficient useful Through largest and most diverse virtual HTS campaign reported date, comprising 318 individual projects, we demonstrate our AtomNet® convolutional neural network...
Post-transition state bifurcations are described that lead to unexpected byproducts in Rh-promoted C–H insertion reactions.
Principal Component Analysis on a series of molecular geometries (<italic>e.g.</italic>, reaction coordinate or trajectory) provides maximum structural variance in the fewest dimensions, and so can offer an objective, comprehensible depiction transformation.
A post-transition state bifurcation (PTSB) involved in a Pummerer-type rearrangement is characterized using density functional theory (DFT) calculations on potential energy stationary points and direct dynamics simulations.
Dynamics calculations are described for carbocation rearrangements involving product-forming pathways with post-transition-state bifurcations. We show that noncovalent interactions associated benzene rings (a simple model of aromatic amino acid side chains) can switch inherent dynamical tendencies competing modes disrotation, establishing meaningful changes in dynamically controlled product selectivity be achieved few weak interactions.
Simulating drug binding and unbinding is a challenge, as the rugged energy landscapes that separate bound unbound states require extensive sampling consumes significant computational resources. Here, we describe use of interactive molecular dynamics in virtual reality (iMD-VR) an accurate low-cost strategy for flexible protein-ligand docking. We outline experimental protocol which enables expert iMD-VR users to guide ligands into out pockets trypsin, neuraminidase, HIV-1 protease, recreate...
Rh-catalyzed C-H insertion reactions to form β-lactones suffer from post-transition state bifurcations, with the same transition states leading ketones and ketenes via fragmentation in addition β-lactones. In such a circumstance, traditional theory cannot predict product selectivity, so we employed ab initio molecular dynamics simulations do provide framework for rationalizing origins of said selectivity. Weak interactions between catalyst substrate were studied using energy decomposition...
An efficient synthesis of stereodefined tetrasubstituted acyclic all-carbon olefins has been developed via a bis(2,6-xylyl)phosphate formation stereoenriched tertiary alcohols, followed by in situ syn-elimination the corresponding phosphates under mild conditions. This chemistry tolerates wide variety electronically and sterically diverse substrates generates desired high yields stereoselectivities (>95:5) most cases. stereocontrolled olefin applied to anticancer drug tamoxifen three steps...
An acid-catalyzed Prins/semipinacol rearrangement cascade reaction of hydroxylated pinene derivatives that leads to tricyclic fenchone-type scaffolds in very high yields and diastereoselectivity has been developed. Quantum chemical analysis the selectivity-determining step provides support for existence an extremely flat potential energy surface around transition state structure. This structure appears be ambimodal, i.e., are formed preference competing formation a bornyl (camphor-type)...
A series of computational laboratory experiments aimed at teaching students principles rational drug design are described and evaluated. These range from an introduction to viewing protein–ligand complexes optimizing geometries potential drugs with quantum chemistry automated docking. Student feedback indicates that such a course increased their appreciation for the roles chemists in discovery–development process.
Cophotolysis of noradamantyldiazirine with the phenanthride precursor dichlorocarbene or phenylchlorodiazirine in pentane at room temperature produces noradamantylethylenes 11% yield slight diastereoselectivity. adamantyldiazirine generates adamantylethylenes 6% no (1)H NMR showed reaction + to be independent solvent, and rate consumption correlated ethylene formation. Laser flash photolysis that phenylchlorocarbene adamantene was concentration. The homoadamantene products k = 9.6 × 10(5)...
When new concepts, models, or theories are introduced in a course, their presentation should be accurate, even if depth is not the goal. In recent publication this Journal, Woodward–Hoffmann rules were invoked context of laboratory experiment, but associated description was inaccurate. Here we aim to clarify theoretical background relevant described and describe computational experiment that could used further illuminate concepts.
Understanding the detailed mechanism by which proteins of marine diatoms such as silaffins are able to control morphology silica oligomers has eluded synthetic chemists and materials scientists for decades. In this study, we use DFT calculations determine how individual amino acid residues silaffin catalyze dimerization. The reaction network formation a dimer was explored using several different small molecules, including water, guanidinium ions, methylammonium latter two molecules...
Low dimensional representations along reaction pathways were produced using newly created Python software that utilises Principal Component Analysis (PCA) to do dimensionality reduction. Plots of these in reduced space, as well the physical meaning axes, are discussed.
Abstract Flow assurance plans typically call for flushing subsea well/manifold jumpers with methanol to displace and inhibit any water accumulated in the jumper prevent formation of hydrate blockages during shutdown. This paper presents results experiments that were conducted evaluate effectiveness injection gas purging on removing inhibiting a jumper. Variables test program included different cuts volume fractions jumper, rate, purge flow rates, oil properties, inclination angle. The tests...
Low dimensional representations along reaction pathways were produced using newly created Python software that utilises Principal Component Analysis (PCA) to do dimensionality reduction. Plots of these in reduced space, as well the physical meaning axes, are discussed.
Review: [103 refs.