A5015535171- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Metal-Catalyzed Oxygenation Mechanisms
- Metal complexes synthesis and properties
- Oxidative Organic Chemistry Reactions
- Porphyrin and Phthalocyanine Chemistry
- Photosynthetic Processes and Mechanisms
- Enzyme-mediated dye degradation
- Lanthanide and Transition Metal Complexes
- Pesticide Exposure and Toxicity
- Market Dynamics and Volatility
- Ocular Infections and Treatments
- Synthetic Organic Chemistry Methods
- CO2 Reduction Techniques and Catalysts
- Global Financial Crisis and Policies
- Metal-Organic Frameworks: Synthesis and Applications
- Advanced Nanomaterials in Catalysis
- Microbial metabolism and enzyme function
- Ferrocene Chemistry and Applications
- Marine Sponges and Natural Products
- Chemical Synthesis and Analysis
- Porphyrin Metabolism and Disorders
- Carcinogens and Genotoxicity Assessment
- Magnetism in coordination complexes
- Synthesis and Catalytic Reactions
University of York
2022-2024
Universidad de Santiago de Chile
2018-2021
Johns Hopkins University
2016-2019
University of Baltimore
2019
Universidad Bernardo O'Higgins
2018
Banco de la República Colombia
2018
Universidad Juárez del Estado de Durango
2017
The use of copper in directed C–H oxidation has been relatively underexplored. In a seminal example, Schönecker showed that and O2 promoted the hydroxylation steroid-containing ligands. Recently, Baran (J. Am. Chem. Soc. 2015, 137, 13776) improved reaction conditions to oxidize similar substrates with excellent yields. both reports, involvement Cu2O2 intermediates was suggested. this collaborative article, we studied mechanism great detail, resulting overhaul previously accepted development...
Primary copper(I)-dioxygen (O2) adducts, cupric-superoxide complexes, have been proposed intermediates in copper-containing dioxygen-activating monooxygenase and oxidase enzymes. Here, mechanisms of C-H activation by reactive copper-(di)oxygen are discussed, with an emphasis on species. Over the past 25 years, many synthetically derived model complexes reported. Due to thermal instability these intermediates, early studies focused increasing their stability obtaining physical...
Copper-dependent metalloenzymes are widespread throughout metabolic pathways, coupling the reduction of O2 with oxidation organic substrates. Small-molecule synthetic analogs useful platforms to generate L/Cu/O2 species that reproduce structural, spectroscopic, and reactive properties some copper-/O2-dependent enzymes. Landmark studies have shown conversion between dicopper(II)-peroxo (L2CuII2(O22-) either side-on peroxo, SP, or end-on trans-peroxo, TP) dicopper(III)-bis(μ-oxo)...
The dioxygen reactivity of a series TMPA-based copper(I) complexes (TMPA=tris(2-pyridylmethyl)amine), with and without secondary-coordination-sphere hydrogen-bonding moieties, was studied at -135 °C in 2-methyltetrahydrofuran (MeTHF). Kinetic stabilization the H-bonded [( (X1)(X2) TMPA)CuII (O2.- )]+ cupric superoxide species achieved, they were characterized by resonance Raman (rR) spectroscopy. structures physical properties (N3- azido analogues compared, O2.- ligand-CuI when an H-bonding...
Structural/electronic influence of metalloenzyme-inspired synthetic heme–peroxo–copper models containing intramolecular hydrogen bonding interactions.
Oxygenase and peroxygenase enzymes generate intermediates at their active sites which bring about the controlled functionalization of inert C-H bonds in substrates, such as enzymatic conversion methane to methanol. To be viable catalysts, however, these must also prevent oxidative damage essential site residues, can occur during both coupled uncoupled turnover. Herein, we use a combination stopped-flow spectroscopy, targeted mutagenesis, TD-DFT calculations, high-energy resolution...
Abstract We report the Cu I /O 2 chemistry of complexes derived from macrocylic ligands 14‐TMC (1,4,8,11‐tetramethyl‐1,4,8,11‐tetraazacyclotetradecane) and 12‐TMC (1,4,7,10‐tetramethyl‐1,4,7,10‐tetraazacyclododecane). While [(14‐TMC)Cu ] + is unreactive towards dioxygen, smaller analog [(12‐TMC)Cu (CH 3 CN)] reacts with O to give a side‐on bound peroxo‐dicopper(II) species ( S P), confirmed by spectroscopic computational methods. Intriguingly, as N4 donor ligand generates P species, thus in...
Attack cancer cells by different mechanisms of action, improves the activity a compound as an anticancer drug.
Abstract A family of six homoleptic [Cu I (L n )] 2 (ClO 4 ) and heteroleptic )(PPh 3 ] bimetallic complexes, in which L are bis‐Schiff base ligands with alkyl spacers variable length ( =2–7 −CH −), were prepared to evaluate the role spacer on formation helicates or mesocates. In series, spectroscopic theoretical studies indicate that preferences for a conformation based energetic parameters, mainly, establishment noncovalent interactions. The odd–even nature preconditions superposition...
Because of concerns that natural aquifers in the region Todos Santos (Baja California Sur, Mexico) might be contaminated by organochlorine pesticides and heavy metals, a case–control study was conducted among consumers non‐consumers well‐ and/or tap‐water to determine risks human health. This based on genotoxic evaluation buccal cells using Comet assay technique. Levels DNA damage group were significantly higher than those control group. However, occupational exposure genotoxicants showed...
The reaction of p-cyano-N,N-dimethylaniline N-oxide, an O-atom donor, with different copper(I) complexes (at room temperature and in acetone) indicates the formation via transfer a high-valent copper oxyl species, CuII–O•, putative key intermediate catalytic cycle copper-containing monooxygenases. p-cyano-N-hydroxymethyl-N-methylaniline p-cyano-N-methylaniline as main products highlight capability this species to hydroxylate strong C–H bonds (bond dissociation energy ∼ 90 kcal/mol). A...
To evaluate a method for measuring the cylinder, sphere, and wavefront of progressive addition lenses (PALs) in eyeglass frames.We examine contour maps PAL assembled an frame using optical system based on Hartmann test. reduce data noise, particularly border frame, we implement Fourier analysis to extrapolate spots outside frame. The are extrapolated up circular pupil that circumscribes compared with obtained from uncut PAL.By can remove edge artifacts within its modal fit Zernike...
Abstract The dioxygen reactivity of a series TMPA‐based copper(I) complexes (TMPA=tris(2‐pyridylmethyl)amine), with and without secondary‐coordination‐sphere hydrogen‐bonding moieties, was studied at −135 °C in 2‐methyltetrahydrofuran (MeTHF). Kinetic stabilization the H‐bonded [( TMPA)Cu II (O 2 .− )] + cupric superoxide species achieved, they were characterized by resonance Raman (rR) spectroscopy. structures physical properties (N 3 − azido analogues compared, O ligand–Cu I when an...
Abstract Oxygenase enzymes generate reactive intermediates at their active sites to effect controlled functionalizations of inert C–H bonds in substrates, such as the enzymatic conversion methane methanol. To be viable catalysts, however, these must also prevent oxidative damage essential site residues, which can occur during turnover absence substrate. Herein we use a combination stopped-flow spectroscopy, targeted mutagenesis, DFT calculations, high-energy resolution fluorescence detection...