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Free-base corroles have long been known to be acidic, readily undergoing deprotonation by mild bases and in polar solvents. The conjugate base, however, has not been structurally characterized until now. Presented here is a first crystal structure of a free-base corrole anion, derived from tris(p-cyanophenyl)corrole, as the tetrabuylammonium salt. The low-temperature (100 K) structure reveals localized hydrogens on a pair of opposite pyrrole nitrogens. DFT calculations identify such a structure as the global minimum but also point to two cis tautomers only 4-7 kcal/mol above the ground state. In terms of free energy, however, the cis tautomers are above or essentially flush with the trans-to-cis barrier so the cis tautomers are unlikely to exist or be observed as true intermediates. Thus, the hydrogen bond within each dipyrrin unit on either side of the molecular pseudo-C2 axis through C10 (i.e., between pyrrole rings A and B or between C and D) qualifies as or closely approaches a low-barrier hydrogen bond. Proton migration across the pseudo-C2 axis entails much higher activation energies >20 kcal/mol, reflecting the relative rigidity of the molecule along the C1-C19 pyrrole-pyrrole linkage.
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A new class of antimony(III) corroles has been described. The photophysical properties of these newly synthesized tetrakis(thiocyano)corrolatoantimony(III) derivatives having four SCN groups on the bipyrrole unit of corrole are drastically altered compared to their ß-unsubstituted corrolatoantimony(III) analogues. The UV-vis and emission spectra of tetrakis(thiocyano)corrolatoantimony(III) derivatives are significantly red-shifted (roughly 30-40 nm) in comparison with their ß-unsubstituted corrolatoantimony(III) derivatives. The Q bands are significantly strengthened. The intensity of the most prominent Q band is roughly 70% that of the Soret band and absorbs strongly at the far-red region, i.e., at 700-720 nm. These molecules emit light in the near-infrared region (700-900 nm). Tetrakis(thiocyano)corrolatoantimony(III) undergoes electrochemical anodic oxidation to form SbVâO species, which facilitates electrocatalytic oxygen evolution reaction (OER) and the activation of benzylic C-H to produce benzoic acid selectively. Under optimized conditions, SbIII-corrole@NF (NF = nickel foam) required an overpotential of 380 mV to reach a 50 mA cm-2 current density, comparable with those of other transition-metal-based complexes. On the other hand, replacing the anodic OER with benzyl alcohol oxidation lowered the required potential by 150 mV (at 300 mA cm-2) to improve the energy efficiency of the electrochemical process.
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Metal complexes of multi-porphyrins and multi-corroles are unique systems that display a host of extremely interesting properties. Availability of free meso and ß positions allow formation of different types of directly linked bis-porphyrins giving rise to intriguing optical and electronic properties. While the fields of metalloporphyrin and corroles monomer have seen exponential growth in the last decades, the chemistry of metal complexes of bis-porphyrins and bis-corroles remain rather underexplored. Therefore, the impact of covalent linkages on the optical, electronic, (spectro)electrochemical, magnetic and electrocatalytic activities of metal complexes of bis-porphyrins and -corroles has been summarized in this review article. This article shows that despite the (still) somewhat difficult synthetic access to these molecules, their extremely exciting properties do make a strong case for pursuing research on these classes of compounds.
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Complejos de Coordinación , Metaloporfirinas , Porfirinas , Complejos de Coordinación/química , Metaloporfirinas/química , Porfirinas/químicaRESUMEN
Tetra(thiocyanato)corrolato-Ag(III) complexes presented here constitute a new class of metallo-corrole complexes. The spectroscopic properties of these complexes are quite unusual and interesting. For example, the absorption spectra of these ß-substituted corrolato-Ag(III) complexes are very different from those of the ß-unsubstituted corrolato-Ag(III) derivatives. Single-crystal XRD analysis of a representative tetra(thiocyanato)corrolato-Ag(III) derivative reveals C-H···Ag interactions. The C-H···Ag interactions are rarely demonstrated in the crystal lattice of a discrete coordination/organometallic compound. Optimization of the hydrogen positions of the crystal structure discloses the geometrical parameters of the said interaction as a Ag···H distance of 2.597 Å and â C-H···Ag of 109.62°. The natural bond orbital analysis provides information about the donor-acceptor orbitals involved in the interactions and their interaction energies. It was observed that the σC-H orbital overlaps with the vacant d-orbital of Ag with an interaction energy of 17.93 kJ/mol. The filled d-orbital of Ag overlaps with the σ*C-H orbital with an interaction energy of 4.79 kJ/mol. The highlights of this work are that the H···Ag distance is outside of the distance range for the typical agostic interaction but fitted with the weak H-bond distance. However, the â C-H···Ag angle is within the range of the agostic interaction. Both crystallographic data and electronic structure calculations reveal that these kinds of intermolecular interactions in square-planar d8 Ag(III) complexes are intermediate in nature. Thus, they cannot be categorically called either hydrogen bonding or agostic interaction.
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A new method of activating corrole macrocycles via an in situ generated SCN radical has been developed at very mild conditions at room temperature. This photoredox reaction resulted in the generation of tetrathiocyanatocorroles in good yields. The synthesis of tetrathiocyanatocorroles was never reported earlier. Single-crystal XRD analysis reveals that the insertion of four thiocyanate moieties at the four ß-pyrrolic positions has imparted significant distortion to the corrole macrocycle. The generated tetrathiocyanatocorroles are different from the parent corroles in many ways. The photophysical properties of the newly synthesized tetrathiocyanatocorroles are dramatically altered from the parent corroles. The absorption feature of these modified corrole derivatives (both position and intensity) bears a nice similarity with the chlorophyll-a macrocycle. Thus, these newly synthesized molecules can be considered as spectroscopic model systems for chlorophyll-a pigments. The observed absorption and emission spectra of these tetrathiocyanatocorroles certainly point out that these newly developed ligand scaffolds and their various metal complexes will have immense potential as pigments in solar cells and also as NIR-emissive dyes. The observed C-H···Au weak interactions in a representative Au(III)-corrole complex point out that these complexes are capable of activating the unfunctionalized C-H groups and thus will have potential implications in C-H activation reactions.
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Porfirinas , Teoría Cuántica , Colorantes , LigandosRESUMEN
Sharpless et al. have described, while performing the molybdenum-catalyzed epoxidation reaction of olefins using alkyl hydroperoxides, that the molybdenum-oxo moiety is an active catalytic species. Thus, continuous efforts have been made to synthesize molybdenum-oxo complexes of different ligand environments. While plenty of such works on molybdenum porphyrins are reported in the literature, related molybdenum corroles are very less reported. The synthesis and characterization of two new oxo-molybdenum(V)-corrolato complexes are described herein. Both the complexes have been fully characterized by several spectroscopic techniques in conjunction with single-crystal X-ray diffraction analysis. The efficacy of the oxo-molybdenum(V)-corrolato complexes for the catalytic epoxidation reaction of olefins with the help of hydroperoxides has also been explored. The catalytic application of oxo-molybdenum(V)-corrolato complexes in the epoxidation reaction has not been reported earlier. A mechanism has been proposed to explain the experimental findings.
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Metal- versus ligand-centered redox processes and the effects of substituents on the ligands on the spectroscopic properties of the metal complexes are at the heart of research on metal complexes with non-innocent ligands. This work presents three examples of chromium complexes that contain both oxido and corrolato ligands, with the substituents on the corrolato ligands being different in the three cases. Combined X-ray crystallographic, electrochemical, UV/Vis/NIR/EPR spectroelectrochemical, and EXAFS/XANES measurements, together with DFT calculations, have been used to probe the complexes in three different redox forms. This combined approach makes it possible to address questions related to chromium- versus corrolato-centered redox processes, and the accessibility (or not) of CrIV , CrV , and CrVI in these complexes, as well as their spin states. To the best of our knowledge, these are the first EXAFS/XANES investigations on Cr-corrolato complexes in different redox forms, and hence these data should set benchmarks for future investigations on such complexes by this method.
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Mixed-valent compounds are fascinating entities that are useful as models for investigating electron-transfer reactions, and find use in a host of biologically relevant redox processes. Though the bio-relevant metal copper is well established in mixed-valent chemistry, the AgII /AgIII mixed-valent combination of its higher congener in a molecular complex has rarely been reported before. This work reports the synthesis of a new ß,ß'-linked bis{corrolato-silver(III)} complex and its characterization in five different redox states. A combination of electrochemistry, spectroelectrochemistry, and DFT calculations point to the existence of a mixed-valent AgII /AgIII and an isovalent AgII /AgII form. Additionally, characterization of the AgIII /AgIII form and ligand-based corrolato-centered mixed-valency is presented as well. These results thus open new avenues for bis-corrolato ligands and for mixed-valency in disilver compounds.
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We present herein the synthesis of three new bis(corrolato-ruthenium(III)) complexes containing unsupported Ru-Ru bonds and their characterization in different redox states. The 1 Hâ NMR spectra of the bis(corrolato-ruthenium(III)) complexes displayed "normal" chemical shifts and the compounds proved to be EPR-silent. Crystallographic characterization of the dimers indicated Ru-Ru distances of 2.175â Å, consistent with a triple bond between the two ruthenium centers. All of the synthesized complexes undergo two successive reversible oxidations and a single reversible reduction. A combination of UV/Vis/NIR/EPR spectroelectrochemical studies and DFT calculations established the redox state distributions in these ruthenium-ruthenium-bonded dimers. Whereas reduction of the dimers is metal-based and leads to metal-metal-bonded mixed-valent RuII -RuIII species, one-electron oxidation largely retains the RuIII -RuIII situation with the generation of metal-bound corrolato radicals. The present study thus concerns the first UV/Vis/NIR/EPR spectroelectrochemical characterization and DFT calculations of ruthenium-ruthenium-bonded rotationally ordered corrole dimers. The mean plane separation between the two corrole units in these dimers is around 3.543â Å, which is in close agreement to that in the "special pair" in chlorophyll. Oxidation of these ruthenium-ruthenium-bonded dimers gives rise to two new electronic absorption bands in the NIR region (similar to those of the special pair), which have apparently not been mentioned/observed in earlier reports on ruthenium-ruthenium-bonded corrole dimers. These bands mainly originate from inter-corrole transitions.
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Aminotransferase assay is often used as a screening test as well as an endpoint for resolution of disease in nonalcoholic fatty liver disease (NAFLD). Aim of the study was to evaluate the relationship of transaminase level with metabolic variables and histology in NAFLD. Single center observational study was conducted in a gastroenterology clinic at Cuttack in coastal Odisha. Subjects were consecutive patients presenting with functional bowel disease and undergoing abdominal sonography. All participants were evaluated for the presence of metabolic syndrome (MS), insulin resistance, liver function test and lipid profile. Various parameters were compared between NAFLD subjects and controls. 53.5 % of NAFLD had normal serum transaminases, whereas 20.8 % of healthy controls had transaminitis. NAFLD patients had significantly higher BMI, fasting plasma glucose, serum transaminases, serum triglycerides, serum insulin and homeostatic model assessment (HOMA) IR than controls. NAFLD patients who had transaminitis had significantly higher incidence of MS and higher mean HOMA IR than those without. There was no significant difference in histopathological features between NAFLD with and without transaminitis. To conclude, over half of NAFLD subjects do not have transaminitis while transaminitis is present in a fifth of healthy people without fatty liver. Hence serum transaminase should not be used as screening test for NAFLD. NAFLD patients with transaminitis had a higher incidence of MS and insulin resistance than those without. However, there was no significant difference in histopathological features between these two groups.
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The most common oxidation states of copper in stable complexes are +I and +II. Cu(III) complexes are often considered as intermediates in biological and homogeneous catalysis. More recently, Cu(IV) species have been postulated as possible intermediates in oxidation catalysis. Despite the importance of these higher oxidation states of copper, spectroscopic data for these oxidation states remain scarce, with such information on Cu(IV) complexes being non-existent. We herein present the synthesis and characterization of three copper corrolato complexes. A combination of electrochemistry, UV/Vis/NIR/EPR spectroelectrochemistry, XANES measurements, and DFT calculations points to existence of three distinct redox states in these molecules for which the oxidation states +II, +III, and +IV can be invoked for the copper centers. The present results thus represent the first spectroscopic and theoretical investigation of a Cu(IV) species, and describe a redox series where Cu(II), Cu(III), and Cu(IV) are discussed within the same molecular platform.
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Macrocycles such as porphyrins and corroles have important functions in chemistry and biology, including light absorption for photosynthesis. Generation of near-IR (NIR)-absorbing dyes based on metal complexes of these macrocycles for mimicking natural photosynthesis still remains a challenging task. Herein, the syntheses of four new Ag(III) corrolato complexes with differently substituted corrolato ligands are presented. A combination of structural, electrochemical, UV/Vis/NIR-EPR spectroelectrochemical, and DFT studies was used to decipher the geometric and electronic properties of these complexes in their various redox states. This combined approach established the neutral compounds as stable Ag(III) complexes, and the one-electron reduced species of all the compounds as unusual, stable Ag(II) complexes. The one-electron oxidized forms of two of the complexes display absorptions in the NIR region, and thus they are rare examples of mononuclear complexes of corroles that absorb in the NIR region. The appearance of this NIR band, which has mixed intraligand charge transfer/intraligand character, is strongly dependent on the substituents of the corrole rings. Hence, the present work revolves round the design principles for the generation of corrole-based NIR-absorbing dyes and shows the potential of corroles for stabilizing unusual metal oxidation states. These findings thus further contribute to the generation of functional metal complexes based on such macrocyclic ligands.
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Complejos de Coordinación/química , Complejos de Coordinación/síntesis química , Porfirinas/química , Porfirinas/síntesis química , Plata/química , Cristalografía por Rayos X , Ligandos , Estructura Molecular , Oxidación-Reducción , Fotosíntesis , Teoría Cuántica , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja CortaRESUMEN
Iron-based compounds possess the capability of inducing cell death due to their reactivity with oxidant molecules, but their specificity towards cancer cells and the mechanism of action are hitherto less investigated. A Fe(salen)Cl derivative has been synthesized that remains active in monomer form. The efficacy of this compound as an anti-tumor agent has been investigated in mouse and human leukemia cell lines. Fe(salen)Cl induces cell death specifically in tumor cells and not in primary cells. Mouse and human T-cell leukemia cell lines, EL4 and Jurkat cells are found to be susceptible to Fe(salen)Cl and undergo apoptosis, but normal mouse spleen cells and human peripheral blood mononuclear cells (PBMC) remain largely unaffected by Fe(salen)Cl. Fe(salen)Cl treated tumor cells show significantly higher expression level of cytochrome c that might have triggered the cascade of reactions leading to apoptosis in cancer cells. A significant loss of mitochondrial membrane potential upon Fe(salen)Cl treatment suggests that Fe(salen)Cl induces apoptosis by disrupting mitochondrial membrane potential and homeostasis, leading to cytotoxity. We also established that apoptosis in the Fe(salen)Cl-treated tumor cells is mediated through caspase-dependent pathway. This is the first report demonstrating that Fe(salen)Cl can specifically target the tumor cells, leaving the primary cells least affected, indicating an excellent potential for this compound to emerge as a next-generation anti-tumor drug.
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Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Cloruros/química , Cloruros/farmacología , Etilenodiaminas/química , Compuestos Férricos/química , Compuestos Férricos/farmacología , Clorometilcetonas de Aminoácidos/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Factor Apoptótico 1 Activador de Proteasas/metabolismo , Línea Celular , Cloruros/síntesis química , Citocromos c/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Etilenodiaminas/síntesis química , Etilenodiaminas/farmacología , Compuestos Férricos/síntesis química , Humanos , Células Jurkat , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Proteína Letal Asociada a bcl/metabolismoRESUMEN
Two novel trans-A2B-corroles and three [(corrolato){FeNO}(6)] complexes have been prepared and characterized by various spectroscopic techniques. In the native state, all these [(corrolato){FeNO}(6)] species are diamagnetic and display "normal" chemical shifts in the (1)H NMR spectra. For two of the structurally characterized [(corrolato){FeNO}(6)] derivatives, the Fe-N-O bond angles are 175.0(4)° and 171.70(3)° (DFT: 179.94°), respectively, and are designated as linear nitrosyls. The Fe-N (NO) bond distances are 1.656(4) Å and 1.650(3) Å (DFT: 1.597 Å), which point toward a significant Fe(III) â NO back bonding. The NO bond lengths are 1.159(5) Å and 1.162(3) Å (DFT: 1.162 Å) and depict their elongated character. These structural data are typical for low-spin Fe(III). Electrochemical measurements show the presence of a one-electron oxidation and a one-electron reduction process for all the complexes. The one-electron oxidized species of a representative [(corrolato){FeNO}(6)] complex exhibits ligand to ligand charge transfer (LLCT) transitions (cor(π) â cor(π*)) at 399 and 637 nm, and the one-electron reduced species shows metal to ligand charge transfer (MLCT) transition (Fe(dπ) â cor(π*)) in the UV region at 330 nm. The shift of the νNO stretching frequency of a representative [(corrolato){FeNO}(6)] complex on one-electron oxidation occurs from 1782 cm(-1) to 1820 cm(-1), which corresponds to 38 cm(-1), and on one-electron reduction occurs from 1782 cm(-1) to 1605 cm(-1), which corresponds to 177 cm(-1). The X-band electron paramagnetic resonance (EPR) spectrum of one-electron oxidation at 295 K in CH2Cl2/0.1 M Bu4NPF6 displays an isotropic signal centered at g = 2.005 with a peak-to-peak separation of about 15 G. The in situ generated one-electron reduced species in CH2Cl2/0.1 M Bu4NPF6 at 295 K shows an isotropic signal centered at g = 2.029. The 99% contribution of corrole to the HOMO of native species indicates that oxidation occurs from the corrole moiety. The results of the electrochemical and spectroelectrochemical measurements and density functional theory calculations clearly display a preference of the {FeNO}(6) unit to get reduced during the reduction step and the corrolato unit to get oxidized during the anodic process. Comparisons are presented with the structural, electrochemical, and spectroelectrochemical data of related compounds reported in the literature, with a particular focus on the interpretation of the EPR spectrum of the one-electron oxidized form.
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Compuestos Férricos/química , Porfirinas/química , Cristalografía por Rayos X , Espectroscopía de Resonancia por Spin del Electrón , Compuestos Férricos/síntesis química , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Oxidación-Reducción , Porfirinas/síntesis química , Espectrofotometría Infrarroja , Espectrofotometría UltravioletaRESUMEN
A variety of complications and associated clinical presentations may be seen in patients with cirrhotic and non-cirrhotic portal hypertension. We present one such case of Upper GI hemorrhage from ectopic duodenal varices in a case of pre-hepatic portal hypertension due to Extrahepatic Portal Venous Obstruction (EHPVO). The case was managed successfully with endovascular Portal Vein Recanalization (PVR) and metallic stent deployment. With adequate technical success, improved symptoms, and laboratory parameters, the patient was discharged on long-term anticoagulation and interval follow-up.
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BACKGROUND AND AIM: Non-alcoholic fatty liver disease (NAFLD) has emerged as the commonest hepatic problem in both developed and developing countries. This study was conducted to delineate the clinical profile of incidentally detected NAFLD patients. METHODS: A retrospective analysis of clinical, biochemical and histological parameters was performed for 632 patients in whom fatty liver was diagnosed by ultrasonography during 2006-2010. Every patient's clinical presentation, history, liver function tests, blood sugar, lipid profile, ultrasonogram, histology and other relevant investigations were analyzed. Patients referred for transaminitis or overt chronic liver disease were excluded. RESULTS: Out of 632 consecutive NAFLD patients, 484 (76.6%) were males and 148 (23.4%) were females. Mean age of our patients was 42.44 +/- 10.18 years. Their mean body mass index (BMI) was 26.14 +/- 3.38 kg/m2. Obesity (BMI > 25), diabetes mellitus, hypertension, hyperlipidemia, metabolic syndrome and insulin resistance were present in 61.7%, 15.2%, 19.8%, 62.0%, 40.0%, and 54.4% patients, respectively. SGOT and SGPT were elevated in 38.29% and 55.1% patients, respectively. The common primary diseases for which these patients sought consultation were non-ulcer dyspepsia (NUD) (54.5%) and irritable bowel syndrome (IBS) (29.4%). Of the 64 patients who underwent liver biopsy, one-fourth had definite NASH while one-third patients had fibrosis. CONCLUSION: In India, incidentally detected NAFLD (IDNAFLD) patients are predominantly middle aged males, most of whom are not lean. Most of these patients seek consultation for functional bowel disease.
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Hígado Graso/diagnóstico , Adulto , Índice de Masa Corporal , Hígado Graso/metabolismo , Hígado Graso/patología , Femenino , Humanos , India , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico , Estudios Retrospectivos , Factores SocioeconómicosRESUMEN
Nonalcoholic fatty liver disease (NAFLD) is a major cause of chronic liver disease globally and in India. The already high burden of NAFLD in India is expected to further increase in the future in parallel with the ongoing epidemics of obesity and type 2 diabetes mellitus. Given the high prevalence of NAFLD in the community, it is crucial to identify those at risk of progressive liver disease to streamline referral and guide proper management. Existing guidelines on NAFLD by various international societies fail to capture the entire landscape of NAFLD in India and are often difficult to incorporate in clinical practice due to fundamental differences in sociocultural aspects and health infrastructure available in India. A lot of progress has been made in the field of NAFLD in the 7 years since the initial position paper by the Indian National Association for the Study of Liver on NAFLD in 2015. Further, the ongoing debate on the nomenclature of NAFLD is creating undue confusion among clinical practitioners. The ensuing comprehensive review provides consensus-based, guidance statements on the nomenclature, diagnosis, and treatment of NAFLD that are practically implementable in the Indian setting.
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Metal complexes bearing nitrido ligands (M≡N) are at the forefront of current scientific research due to their resemblances with the metal complexes involved in the nitrogen fixation reactions. An oxo(corrolato)chromium(V) complex was used as a precursor complex for the facile synthesis of a new nitrido(corrolato)chromium(V) complex. The nitrido(corrolato)chromium(V) complex was characterized by various spectroscopic techniques. Density functional theory (DFT) calculations were performed on the nitrido(corrolato)chromium(V) complex to assign the vibrational and electronic transitions of this complex. The chromium-nitrogen (nitrido) bond distance obtained in the DFT-optimized structure is 1.530 Å and matches well with the earlier reported authentic Cr≡N bond distances obtained from the single-crystal X-ray diffraction data. This nitrido(corrolato)chromium(V) compound exhibited a sharp Soret band at 438 nm and a Q band at 608 nm. DFT calculations deliver that the origin of the bands at 438 and 608 nm is due to the intraligand charge transfer transitions. The nitrido(corrolato)chromium(V) complex showed one reversible oxidation and one reversible reduction couple at +0.53 and -0.06 V, respectively, vs the Ag/AgCl reference electrode. The simulation of the electron paramagnetic resonance data of the nitrido(corrolato)chromium(V) compound provided the following parameters: g iso = 1.987, A 53Cr = 26 G, and A 14N = 2.71 G. From all these analyses, we can conclude that the electronic configuration in the native state of nitrido(corrolato)chromium(V) can be best described as [(cor3-)CrV(N3-)]-. Reactions of nitrido(corrolato)chromium(V) with the chloro(porphyrinato)chromium(III) complex resulted in a complete intermetal N atom transfer reaction between chromium corrole and chromium porphyrin complexes. A second-order rate constant of 4.29 ± 0.10 M-1 s-1 was obtained for this reaction. It was also proposed that this reaction proceeds via a bimetallic µ-nitrido intermediate.
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Presented herein are two fully characterized gold tetrathiocyanocorroles representing a potentially significant new class of NIR-emissive 5d-metallocorroles. The four SCN groups on the bipyrrole unit of the corrole exert a powerful electron-withdrawing effect, upshifting both the oxidation and reduction potentials by roughly half a volt relative to their unsubstituted counterparts. That said, the upshift of the LUMO is somewhat higher than that of the HOMO so these complexes also exhibit a smaller HOMO-LUMO gap, as evinced in both electrochemical measurements and Q band energies (â¼595 nm relative to â¼571 nm for their SCN-free counterparts). The new compounds exhibit NIR phosphorescence under ambient conditions with emission maxima around 900 nm (compared with 790 nm for simple Au triarylcorroles), phosphorescence quantum yields around 0.3%, phosphorescence lifetimes around 10 µs, and singlet oxygen sensitization with a quantum yield of around 50 ± 5% in solution, together signifying wide-ranging potential applications as triplet photosensitizers in oxygen sensing and photodynamic therapy.
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Porfirinas , Oxígeno Singlete , Oro , Oxígeno , Porfirinas/química , Oxígeno Singlete/químicaRESUMEN
Background and aims: Nonalcoholic fatty liver disease (NAFLD) is very common in both Asian and Western countries. Geographic variation leads to differences in epidemiological and demographic characters of NAFLD patients. Studies conducted upon different ethnic groups in the United States (US) show a higher prevalence of NAFLD in Hispanics and African-Americans. There is however, a paucity of studies involving Asians. It has been observed that Asian-Indian NAFLD patients have unique characteristics compared to their counterparts in the West. This study is the first attempt at comparing the characteristics of Asian-Indian and US NAFLD patients. Materials and Methods: A retrospective analysis of clinical, biochemical, and histological data was performed for 633 Asian-Indian NAFLD patients and 451 US NAFLD patients. Clinical parameters [age, gender, body mass index (BMI), diabetes, hypertension, etc.], biochemical tests (liver function tests, lipid profile, and fasting blood sugar), hepatic ultrasound and hepatic histology were compared between the two cohorts. Results: Eighty-two percent of US NAFLD patients were more than 40 years of age compared to 51.3% of Asian-Indian patients (p <0.01). US (male 56.3%) and Asian-Indian (male 81.7%) (p <0.01) patients differed from each other as regards gender prevalence. Rates of obesity were greater in the US patients compared to Asian-Indians (BMI 32.6 ± 5.3 kg/m2 vs 26.2 ± 3.4 kg/m2). There was a higher prevalence of both diabetes and hypertension (diabetes 42.1% vs 33%, and hypertension 56.8% vs 29.7%, p ≤0.01) in US patients. ALT levels were also significantly higher in US NAFLD patients compared to Asian-Indians (ALT 82.78 ± 71.30 vs 53.66 ± 37, p ≤0.01). A higher proportion of US patients were found to have the more advanced liver disease at the time of diagnosis compared to Asian-Indians (Stage 3 fibrosis 10.42% vs 0%, and Stage 4 fibrosis 2.66% vs 0%, p <0.01). Conclusion: Asian-Indian and US NAFLD patients differ significantly on several parameters. Further studies need to be carried out to understand the mechanistic basis of these differences better. How to cite this article: Singh SP, Panigrahi MK, Patel A, et al. Comparison of Clinical, Biochemical, and Histopathologic Profiles between NAFLD in Asian-Indians and United States Adults. Euroasian J Hepato-Gastroenterol 2022;12(Suppl 1):S15-S18.