A5059773208- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Metal complexes synthesis and properties
- Lanthanide and Transition Metal Complexes
- Magnetism in coordination complexes
- Metal-Catalyzed Oxygenation Mechanisms
- Electrochemical Analysis and Applications
- Infrared Target Detection Methodologies
- Crystallography and molecular interactions
- Enzyme-mediated dye degradation
- Oxidative Organic Chemistry Reactions
- Coenzyme Q10 studies and effects
- Ferrocene Chemistry and Applications
- Food Supply Chain Traceability
- Electrochemical sensors and biosensors
- Remote-Sensing Image Classification
- Diagnosis and Treatment of Venous Diseases
- Erosion and Abrasive Machining
- Chromium effects and bioremediation
- Metalloenzymes and iron-sulfur proteins
- Sulfur-Based Synthesis Techniques
- Asymmetric Hydrogenation and Catalysis
- Radical Photochemical Reactions
- Image and Signal Denoising Methods
- Microbial Metabolism and Applications
Universidad Nacional Autónoma de México
1993-2025
Federico Santa María Technical University
2024
Universitat Autònoma de Barcelona
2017
Rede de Química e Tecnologia
2010
Consejo Superior de Investigaciones Científicas
2007
New Jersey Institute of Technology
2005
Hydrogenation and dehydrogenation reactions are fundamental in chemistry essential for all living organisms. We employ density functional theory (DFT) to understand the reaction mechanism of oxidative (ODH) pyridyl-amine complex [FeIIIL3]3+ (L3, 1,9-bis(2′-pyridyl)-5-[(ethoxy-2″-pyridyl)methyl]-2,5,8-triazanonane) mono-imine [FeIIL4]2+ (L4, 1,9-bis(2′-pyridyl)-5-[(ethoxy-2″-pyridyl)methyl]-2,5,8-triazanon-1-ene) presence dioxygen. The nitrogen radical [FeIIL3N8•]2+, formed by deprotonation...
Thermus thermophilus HB27 laccase (Tth-Lac) is a thermostable enzyme that contains β-hairpin (Ala292-Gln307) covering the substrate entrance. We analyzed role of this in enzymatic activity Tth-Lac through three mutants: two variants without (C1Tth-Lac and C2Tth-Lac) one with partially modified (P1Tth-Lac). Enzymatic was assayed different substrates copper. C1Tth-Lac showed higher dependency on copper, increasing its by 1600-fold for syringaldazine (SGZ). All mutants presented than phenolic...
During the last 20 years multiple roles of nitric oxide gas (•NO) have been uncovered in plant growth, development and many physiological processes. In seed plants enzymatic synthesis •NO is mediated by a synthase (NOS)-like activity performed still unknown enzyme(s) nitrate reductase (NR). green algae production has linked only to NR activity, although NOS gene was reported for Ostreococcus tauri O. lucimarinus, no other Viridiplantae species such gene. As there information about neither...
Temperature-dependent magnetic susceptibility and multi-frequency EPR (9.4, 34.5, 94 188 GHz) spectroscopic measurements have been carried out together with an X-ray study at 100 K to [Fe(DMSO)6](NO3)3. The iron(III) ion remains high-spin (S = 5/2) in the temperature range studied, therefore, data were interpreted using conventional S 5/2 spin Hamiltonian. A full analysis of spectra 95 GHz a powdered sample 290 revealed that they are extremely sensitive D E values. zfs parameters precisely...
Several studies have described that quinoid rings with electron-rich olefins at remote position experience changes in their redox potential. Since the original description of these changes, different approaches been developed to describe properties binding sites ubiquinones. The origin this phenomenon has attributed lateral chain flexibility and its effect on recognition between proteins substrates associated important biological activity. use electrochemical−electron spin resonance (EC−ESR)...
Gluconacetobacter diazotrophicus stands out among the acetic acid bacteria as it fixes dinitrogen and is a true endophyte. It has set of constitutive enzymes to oxidize ethanol acetaldehyde which upregulated during N2-dependent growth. The membrane-bound alcohol dehydrogenase (ADH) heterodimer (subunit I ≈ 72 kDa, subunit II 44 kDa) constitutes an important component this organism. ADH Ga. typical quinohemoprotein with one pyrroloquinoline quinone (PQQ) four c-type cytochromes. For first...
For the first time, HF-EPR (94.5 GHz) spectroscopy has been used to determine crystal field parameters in chromium(III) coordination compounds. The large zero-field splitting of dark-green photochromic trans-RSSR-[CrCl2(cyclam)]2ZnCl4, 1, red–purple trans-RSSR-[CrCl2(cyclam)]Cl, 2 and trans-RSSR-[CrCl2(cyclam)]Cl·4H2O·0.5HCl, 3, where cyclam = 1,4,8,11-tetraazacyclotetradecane, have obtained. A full analysis EPR spectra at 94.5 GHz diluted complexes 3 300 K revealed that they are extremely...
The non-metallic chemical element sulfur, 3216S , referred to in Genesis as brimstone and identified by Lavoisier, is the tenth most abundant universe fifth common on Earth. Important inorganic forms of sulfur biosphere are elemental (S8), sulfate (SO2-4), sulfide (S2-), sulfite (SO2-3), thiosulfate, (S2O23), polythionates (S3O62-; S4O62-). Because its wide range stable oxidation states, from +6to -2, plays important roles central biochemistry a structural redoxactive intimately related life...
Voltammetric and spectroelectrochemical-ESR studies of the electro-reduction Perezone five substituted anilinoperezones (R = -H, -OCH3; -CH3; -CN, -Br) their dihydroderivatives in acetonitrile were made. The results showed that PZ APZs double bond at C(12)-C(13) can be involved with quinone ring. values EpcI-EpaI APZHs indicated a increase acidity -OH, caused by lack logical production hydroquinone. On other hand, corresponding to imply process would stop hydroquinone monoanion, what is...
The coordination behavior of the antiulcer drug cimetidine (cime) towards transition metal ions was investigated. synthesis and characterization [Cr(cime)2Cl2]Cl·3H2O, [Co(cime)Cl2]·5H2O, [Co(cime)3Cl]Cl·3H2O, [Ni(cime)Cl2(H2O)2]·H2O, [Cu(cime)Cl2]·2H2O, [Cu(cime)2Cl(H2O)]Cl·H2O, [Cu(cime)3Cl2]·3H2O, [Cu2(cime)Cl4], [Zn(cime)Cl2]·1.5H2O are discussed, where cime acts as monodentate (imidazole N3) or bidentate ligand (N3 S8). IR, UV-vis, EPR NMR spectroscopies, mass spectrometry (FAB+), were...
Voltammetric and spectroelectrochemical-ESR studies of the electro-reduction five substituted 4-R-2-nitrophenols (R = - H, -OCH3; -CH3; -CN, -CF3) in acetonitrile were made. The results showed that at potential values near first reduction peak, no ESR signals was recorded for 2-nitrophenol, indicating a difference stability radical anion compared to behavior reported DMSO. However, corresponding second spectrum this species detected. Since potential, is related transformation conjugated base...
Multitask bus for small satellites is being developed at the University of Mexico (UNAM) conduction LEO communications, remote sensing, and astronomical missions. The first prototype, SATEX-1, to be launched by Ariane in mid 1994, a 50 Kg engineering test satellite with primary communications payload CCD camera low resolution imaging, as secondary payload. SATEX-1 has been under design development several years will constructed research institutions, finance from Ministry Communications...