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1.
Org Biomol Chem ; 22(20): 4123-4134, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38700442

RESUMO

A family of stilbenyl-azopyrroles compounds 2a-d and 3a-d was efficiently obtained via a Mizoroki-Heck C-C-type coupling reaction between 2-(4'-iodophenyl-azo)-N-methyl pyrrole (1a) and different vinyl precursors. The influence of the π-conjugated backbone and the effect of the pyrrole moiety were correlated with their optical properties. Studies via UV-Visible spectrophotometry revealed that the inclusion of EWG or EDG favors a red-shift of the main absorption band in these azo compounds compared with their non-substituted analogues. Furthermore, there is a clear influence between the half-life of the Z isomer formed by irradiation with white light and the push-pull behavior of the molecules. In several cases, the stilbenyl-azopyrroles led to the formation of J-type aggregates in binary MeOH : H2O solvents, which are of interest for water compatible applications.

2.
Molecules ; 27(3)2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35164340

RESUMO

A new synthetic alternative to the synthesis of 3-methyl indoles and 3-methyl indoline-2-ols with an excellent atomic economy is presented in this study. It is demonstrated that the intramolecular interrupted hydroaminomethylation (HAM) reaction is a powerful tool for the formation of these compounds, which exhibit wide-ranging biological activity. Several N-Protected-2-vinyl anilines were synthesized and involved in the reaction producing the corresponding 3-methylindole or 3-methyl indoline-2-ol depending on the nature of the N-protecting groups.

3.
Org Biomol Chem ; 19(35): 7497-7517, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34524345

RESUMO

2-Thiazolines are important building blocks in organic synthesis and are of great importance in many areas of chemistry. At the end of the last century, the use of 2-thiazolines increased in a significant way, especially in synthesis and catalysis. This review highlights the synthetic and catalytic value of 2-thiazolines in the last two decades. We will discuss the new synthetic methodologies for obtaining these heterocycles including new schemes for accessing their asymmetric versions. Most of the new catalytic applications include a variety of 2-thiazoline ligands containing diverse donor atoms, which in combination with metals like Pd, Ir, and Cu, among others, exhibit remarkable catalytic performances.

4.
Org Biomol Chem ; 18(8): 1657-1670, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32048680

RESUMO

A new family of push-pull biphenyl-azopyrrole compounds 3b-g and 4b-d was efficiently obtained via a Suzuki cross-coupling reaction between 2-(4'-iodophenyl-azo)-N-methyl pyrrole (1a) or 3-(4'-iodophenyl-azo)-1,2,5-trimethyl pyrrole (2a) and 4'-substituted phenyl boronic acids in excellent yields. The influence of the π-biphenyl backbone and pyrrole pattern substitution was correlated with their optical properties. Solvatochromic studies via UV-visible spectrophotometry revealed that the inclusion of a 4'-nitro-biphenyl fragment favors a red-shift of the main absorption band in these azo compounds compared with their non-substituted analogues. Likewise, optical band-gaps were estimated by means of electronic absorption spectra and correlated with TD-DFT studies. The pyrrole pattern substitution and the π-conjugated backbone exhibit a clear influence on their thermal isomerization kinetics at room temperature. In all cases, biphenylazo-pyrrole compounds lead to the formation of J-type aggregates in binary MeOH : H2O solvents. Under these conditions, compounds 3b-c undergo a water-assisted cis-to-trans isomerization at room temperature.

5.
Stud Mycol ; 96: 141-153, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32206138

RESUMO

Dothideomycetes is the largest class of kingdom Fungi and comprises an incredible diversity of lifestyles, many of which have evolved multiple times. Plant pathogens represent a major ecological niche of the class Dothideomycetes and they are known to infect most major food crops and feedstocks for biomass and biofuel production. Studying the ecology and evolution of Dothideomycetes has significant implications for our fundamental understanding of fungal evolution, their adaptation to stress and host specificity, and practical implications with regard to the effects of climate change and on the food, feed, and livestock elements of the agro-economy. In this study, we present the first large-scale, whole-genome comparison of 101 Dothideomycetes introducing 55 newly sequenced species. The availability of whole-genome data produced a high-confidence phylogeny leading to reclassification of 25 organisms, provided a clearer picture of the relationships among the various families, and indicated that pathogenicity evolved multiple times within this class. We also identified gene family expansions and contractions across the Dothideomycetes phylogeny linked to ecological niches providing insights into genome evolution and adaptation across this group. Using machine-learning methods we classified fungi into lifestyle classes with >95 % accuracy and identified a small number of gene families that positively correlated with these distinctions. This can become a valuable tool for genome-based prediction of species lifestyle, especially for rarely seen and poorly studied species.

6.
Rep Pract Oncol Radiother ; 25(4): 562-567, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32494229

RESUMO

AIM: The aim of this study was to assess treatment modalities, treatment response, toxicity profile, disease progression and outcomes in 14 patients with a confirmed diagnosis of primary cutaneous T-cell lymphoma (PCTCL) treated with total skin electron beam therapy (TSEBT). BACKGROUND: Primary cutaneous lymphomas (PCLs) are extranodal non-Hodgkin lymphomas originating in the skin without evidence of extracutaneous disease at diagnosis. Despite advances in systemic and local therapy options, the management of advanced stages remains mostly palliative. MATERIALS AND METHODS: This is a retrospective study of patients with PCTCL, diagnosed and treated in a reference center in Mexico City, analyzing treatment modalities, response to treatment, long-term outcome, and mortality. RESULTS: Eight males (57%) and 6 (43%) females were identified. Most patients were stage IVA (n = 5, 36%) followed by stage IB and IIB (28.5% and 21.4%, respectively). Eleven patients received the low-dose RT scheme (12 Gy), 1 patient, the intermediate-dose RT scheme (24 Gy), and 2 patients, the conventional-dose RT scheme (36 Gy). Mean follow-up time was 4.6 years. At first follow-up examination, 6-8 weeks after radiotherapy, the overall response rate (ORR) for the cohort was 85%. The median PFS for the whole cohort was 6 months. CONCLUSION: This study reinforces the role of TSEBT when compared with other treatment modalities and novel agents. Low-dose TSEBT is now widely used because of the opportunity for retreatment.

7.
J Appl Microbiol ; 127(2): 370-378, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31009147

RESUMO

AIMS: A major drawback of using dairy slurry as fertilizer is that it may contains pathogens such as Mycobacterium avium subsp. paratuberculosis (MAP), and it could represent a risk to animal and public health. Thus, the aim of this study was to evaluate the fate of MAP and bacterial communities in dairy slurry after chemical treatments. METHODS AND RESULTS: Cattle slurry, naturally contaminated with MAP, was collected from a dairy herd and divided into 32 glass bottles which were assigned to eight different treatments (control, 3·0% CaO, 0·5% NaOH; 0·087%, 0·11% and 0·14% H2 SO4 ; and 1·0 and 2·5% KMnO4 ). Treated dairy slurry samples were evaluated at 0, 1, 3, 7, 15, 30 and 60-days following treatment application for viable MAP and dairy slurry pH, and in addition temperature in this material was monitored continuously. Bacterial counts were estimated at each sampling time. A Bayesian zero-inflated Poisson mixed model was fitted to assess the effect of each treatment on the count of MAP cells. Model results indicated that only the 3·0% CaO treatment had a statistically important negative effect on MAP counts during the study period. For most treatments, MAP was undetectable immediately after chemical treatment but re-appeared over time, in some replicates at low concentrations. However, in those cases MAP counts were not statistically different than the control treatment. Regarding the fate of the other bacterial populations, the Firmicutes phylum was the dominant population in the un-treated slurry while Clostridia class members were among the most prevalent bacteria after the application of most chemical treatments. CONCLUSION: Only 3% CaO treatment had a statistically important negative effect on MAP viability in cattle slurry. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides evidence of MAP partial control in dairy slurry. This information should be considered as a best management practice to reduce MAP and other pathogens for slurry management on dairy farms.


Assuntos
Antibacterianos/farmacologia , Indústria de Laticínios , Mycobacterium avium subsp. paratuberculosis/efeitos dos fármacos , Animais , Teorema de Bayes , Compostos de Cálcio/farmacologia , Bovinos , Feminino , Fertilizantes , Esterco/microbiologia , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Óxidos/farmacologia
8.
Mol Phylogenet Evol ; 113: 33-48, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28487262

RESUMO

Phylogenetics is undergoing a revolution as large-scale molecular datasets reveal unexpected but repeatable rearrangements of clades that were previously thought to be disparate lineages. One of the most unusual clades of fishes that has been found using large-scale molecular datasets is an expanded Syngnathiformes including traditional long-snouted syngnathiform lineages (Aulostomidae, Centriscidae, Fistulariidae, Solenostomidae, Syngnathidae), as well as a diverse set of largely benthic-associated fishes (Callionymoidei, Dactylopteridae, Mullidae, Pegasidae) that were previously dispersed across three orders. The monophyly of this surprising clade of fishes has been upheld by recent studies utilizing both nuclear and mitogenomic data, but the relationships among major lineages within Syngnathiformes remain ambiguous; previous analyses have inconsistent topologies and are plagued by low support at deep divergences between the major lineages. In this study, we use a dataset of ultraconserved elements (UCEs) to conduct the first phylogenomic study of Syngnathiformes. UCEs have been effective markers for resolving deep phylogenetic relationships in fishes and, combined with increased taxon sampling, we expected UCEs to resolve problematic syngnathiform relationships. Overall, UCEs were effective at resolving relationships within Syngnathiformes at a range of evolutionary timescales. We find consistent support for the monophyly of traditional long-snouted syngnathiform lineages (Aulostomidae, Centriscidae, Fistulariidae, Solenostomidae, Syngnathidae), which better agrees with morphological hypotheses than previously published topologies from molecular data. This result was supported by all Bayesian and maximum likelihood analyses, was robust to differences in matrix completeness and potential sources of bias, and was highly supported in coalescent-based analyses in ASTRAL when matrices were filtered to contain the most phylogenetically informative loci. While Bayesian and maximum likelihood analyses found support for a benthic-associated clade (Callionymidae, Dactylopteridae, Mullidae, and Pegasidae) as sister to the long-snouted clade, this result was not replicated in the ASTRAL analyses. The base of our phylogeny is characterized by short internodes separating major syngnathiform lineages and is consistent with the hypothesis of an ancient rapid radiation at the base of Syngnathiformes. Syngnathiformes therefore present an exciting opportunity to study patterns of morphological variation and functional innovation arising from rapid but ancient radiation.


Assuntos
Sequência Conservada/genética , Genômica/métodos , Filogenia , Smegmamorpha/genética , Animais , Composição de Bases/genética , Sequência de Bases , Teorema de Bayes , Funções Verossimilhança , Alinhamento de Sequência , Especificidade da Espécie
9.
J Clin Pharm Ther ; 41(4): 444-446, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27159430

RESUMO

WHAT IS KNOWN AND OBJECTIVE: Limited data are available on co-administration of acenocoumarol with direct-acting antiviral agents for chronic hepatitis C virus infection. CASE SUMMARY: We report a case of a patient who required a significant increase in acenocoumarol weekly dose probably due to an interaction with ombitasvir/paritaprevir/ritonavir and/or dasabuvir. A causality assessment of the drug-drug interaction leading to a reduced INR was conducted according to the Naranjo algorithm. A score of 6 suggested that the adverse drug reaction was probable. WHAT IS NEW AND CONCLUSION: Because of possible INR abnormalities during the concomitant use of acenocoumarol, ombitasvir/paritaprevir/ritonavir and dasabuvir, clinicians should closely monitor INR values.

10.
J Evol Biol ; 28(5): 1080-90, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25818759

RESUMO

Several hypotheses have been proposed to explain the limitation of brain size in vertebrates. Here, we test three hypotheses of brain size evolution using marine teleost fishes: the direct metabolic constraints hypothesis (DMCH), the expensive tissue hypothesis and the temperature-dependent hypothesis. Our analyses indicate that there is a robust positive correlation between encephalization and basal metabolic rate (BMR) that spans the full range of depths occupied by teleosts from the epipelagic (< 200 m), mesopelagic (200-1000 m) and bathypelagic (> 4000 m). Our results disentangle the effects of temperature and metabolic rate on teleost brain size evolution, supporting the DMCH. Our results agree with previous findings that teleost brain size decreases with depth; however, we also recover a negative correlation between trophic level and encephalization within the mesopelagic zone, a result that runs counter to the expectations of the expensive tissue hypothesis. We hypothesize that mesopelagic fishes at lower trophic levels may be investing more in neural tissue related to the detection of small prey items in a low-light environment. We recommend that comparative encephalization studies control for BMR in addition to controlling for body size and phylogeny.


Assuntos
Encéfalo/crescimento & desenvolvimento , Metabolismo Energético , Peixes/metabolismo , Biologia Marinha , Animais , Encéfalo/metabolismo , Temperatura
11.
J Evol Biol ; 27(8): 1536-48, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24890604

RESUMO

Sharks occupy marine habitats ranging from shallow, inshore environments to pelagic, and deepwaters, and thus provide a model system for testing how gross habitat differences have shaped vertebrate macroevolution. Palaeontological studies have shown that onshore lineages diversify more quickly than offshore taxa. Among onshore habitats, coral reef-association has been shown to increase speciation rates in several groups of fishes and invertebrates. In this study, we investigated whether speciation rates are habitat dependent by generating the first comprehensive molecular timescale for shark divergence. Using phylogenetic comparative methods, we rejected the hypothesis that shelf (i.e. onshore) lineages have higher speciation rates compared to those occupying deepwater and oceanic (i.e. offshore) habitats. Our results, however, support the hypothesis of increased speciation rates in coral reef-associated lineages within the Carcharhinidae. Our new timetree suggests that the two major shark lineages leading to the extant shark diversity began diversifying mostly after the end-Permian mass extinction: the squalimorphs into deepwater and the galeomorphs into shelf habitats. We suggest that the breakdown of the onshore-offshore speciation rate pattern in sharks is mediated by success in deepwater environments through ecological partitioning, and in some cases, the evolution of morphological novelty.


Assuntos
Evolução Biológica , Ecossistema , Especiação Genética , Filogenia , Tubarões/fisiologia , Animais , Simulação por Computador , Recifes de Corais , Geografia , Modelos Genéticos , Tubarões/genética
12.
Appl Opt ; 53(33): 7872-6, 2014 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-25607861

RESUMO

We use terahertz time-domain spectroscopy, combined with effective-medium theory, to measure the moisture content and thickness of leather simultaneously. These results demonstrate that this method could become a standard quality control test for the industrial tanning process.

13.
Dalton Trans ; 53(5): 2231-2241, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38193761

RESUMO

We herein report the synthesis and catalytic application of a new family of dinuclear Cu(I) complexes based on [N,P]-pyrrole ligands. The Cu(I) complexes (4a-d) were obtained in good yields and their catalytic properties were evaluated in the1,3-dipolar cycloaddition of azomethine ylides and electron-deficient alkenes. The air-stable complexes 4a-d exhibited high endo-diasteroselectivity to obtain substituted pyrrolidines, and the catalytic system showed excellent reactivity and wide substitution tolerance.

14.
Appl Environ Microbiol ; 79(12): 3544-52, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23542616

RESUMO

The study assessed the effect of soil slope on Mycobacterium avium subsp. paratuberculosis transport into rainwater runoff from agricultural soil after application of M. avium subsp. paratuberculosis-contaminated slurry. Under field conditions, 24 plots of undisturbed loamy soil 1 by 2 m(2) were placed on platforms. Twelve plots were used for water runoff: 6 plots at a 3% slope and 6 plots at a 15% slope. Half of the plots of each slope were treated with M. avium subsp. paratuberculosis-contaminated slurry, and half were not treated. Using the same experimental design, 12 plots were established for soil sampling on a monthly basis using the same spiked slurry application and soil slopes. Runoff following natural rainfall was collected and analyzed for M. avium subsp. paratuberculosis, coliforms, and turbidity. M. avium subsp. paratuberculosis was detected in runoff from all plots treated with contaminated slurry and one control plot. A higher slope (15%) increased the likelihood of M. avium subsp. paratuberculosis detection but did not affect the likelihood of finding coliforms. Daily rainfall increased the likelihood that runoff would have coliforms and the coliform concentration, but it decreased the M. avium subsp. paratuberculosis concentration in the runoff. When there was no runoff, rain was associated with increased M. avium subsp. paratuberculosis concentrations. Coliform counts in runoff were related to runoff turbidity. M. avium subsp. paratuberculosis presence/absence, however, was related to turbidity. Study duration decreased bacterial detection and concentration. These findings demonstrate the high likelihood that M. avium subsp. paratuberculosis in slurry spread on pastures will contaminate water runoff, particularly during seasons with high rainfall. M. avium subsp. paratuberculosis contamination of water has potential consequences for both animal and human health.


Assuntos
Agricultura/métodos , Água Doce/microbiologia , Mycobacterium avium subsp. paratuberculosis/genética , Solo/análise , Movimentos da Água , Contagem de Células , Chile , Mycobacterium avium subsp. paratuberculosis/isolamento & purificação , Nefelometria e Turbidimetria , Chuva , Reação em Cadeia da Polimerase em Tempo Real , Análise de Regressão
15.
J Evol Biol ; 26(5): 1003-18, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23496826

RESUMO

Habitat shifts are implicated as the cause of many vertebrate radiations, yet relatively few empirical studies quantify patterns of diversification following colonization of new habitats in fishes. The pufferfishes (family Tetraodon-tidae) occur in several habitats, including coral reefs and freshwater, which are thought to provide ecological opportunity for adaptive radiation, and thus provide a unique system for testing the hypothesis that shifts to new habitats alter diversification rates. To test this hypothesis, we sequenced eight genes for 96 species of pufferfishes and closely related porcupine fishes, and added 19 species from sequences available in GenBank. We time-calibrated the molecular phylogeny using three fossils, and performed several comparative analyses to test whether colonization of novel habitats led to shifts in the rate of speciation and body size evolution, central predictions of clades experiencing ecological adaptive radiation. Colonization of freshwater is associated with lower rates of cladogenesis in pufferfishes, although these lineages also exhibit accelerated rates of body size evolution. Increased rates of cladogenesis are associated with transitions to coral reefs, but reef lineages surprisingly exhibit significantly lower rates of body size evolution. These results suggest that ecological opportunity afforded by novel habitats may be limited for pufferfishes due to competition with other species, constraints relating to pufferfish life history and trophic ecology, and other factors.


Assuntos
Ecossistema , Especiação Genética , Filogenia , Tetraodontiformes/genética , Animais , Fósseis , Genes Mitocondriais
16.
J Hosp Infect ; 134: 50-56, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36754289

RESUMO

BACKGROUND: Multidrug-resistant organisms (MDROs) are prevalent on high-touch surfaces in multi-patient rooms. AIM: To quantify the impact of hanging single-use cleaning/disinfecting wipes next to each bed. Pre-specified outcomes were: (1) hospital-acquired infections (HAIs), (2) cleaning frequency, (3) MDRO room contamination, (4) new MDRO acquisitions, and (5) mortality. METHODS: Clustered randomized crossover trial at Shamir Medical Center, Israel (October 2016 to January 2018). Clusters were randomly assigned to use for cleaning either single-use quaternary ammonium wipes (Clinell) or standard practices (reusable cloths and buckets with bleach). Six-month intervention periods were implemented in alternating sequence, separated by a washout period. Five high-touch surfaces were monitored by fluorescent markers. Study outcomes were compared between periods using generalized estimating equations, Poisson regression, and Cox proportional hazards models. FINDINGS: Overall, 7725 patients were included (47,670 person-days), 3793 patients in rooms with intervention cleaning and 3932 patients in rooms with standard practices. During the intervention, there was no significant difference in HAI rates (incidence rate ratio: 1.6; 95% confidence interval (CI): 0.7-3.5; P = 0.3). However, in intervention rooms, the frequency of environmental cleaning was higher (odds ratio: 3.73; 95% CI: 2.0-7.1; P < 0.0001), MDRO environmental contamination rate was insignificantly lower (odds ratio: 0.7; 95% CI: 0.5-1.0; P = 0.06), new MDRO acquisition rate was lower (hazard ratio: 0.4; 95% CI: 0.2-1.0; P = 0.04), and in-hospital mortality rate was lower (incidence rate ratio: 0.8; 95% CI: 0.7-1.0; P = 0.03). CONCLUSION: Hanging single-use cleaning/disinfecting wipes next to each bed did not affect the HAI rates but did improve the frequency of cleaning, reduce MDRO environmental contamination, and was associated with reduced incidence of new MDRO acquisitions and reduced mortality. This is a feasible, recommended practice to improve patient outcomes in multi-patient rooms.


Assuntos
Infecção Hospitalar , Quartos de Pacientes , Humanos , Desinfecção , Estudos Prospectivos , Estudos Cross-Over , Hospitais , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle
17.
Dalton Trans ; 52(9): 2722-2734, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36748862

RESUMO

The synthesis of a series of ferrocenylvinylketenes as stable η4-[Fe(CO)3] complexes (3a-f) was successfully accomplished through the reaction of η2-[Fe(CO)4] complexes under mild carbonylation conditions. The reactivity of 3a-f under thermal conditions afforded the unexpected formation of a novel family of (µ2,η3-allyl-η5-oxapentadienyl)diiron pentacarbonyl complexes 5a-f proposed to be formed by a sequence metathesis-haptotropic rearrangement between the starting η4-vinylketene iron(0) complex 3 and a η4-vinylcarbene iron(0) complex trapped in situ after a reversible carbonylation process favored by the thermal conditions. An electron density distribution analysis (EDD) of 5e using high-resolution X-ray diffraction data in combination with the DFT framework was performed to understand the electronic communication between the two iron fragments.

18.
Dalton Trans ; 52(48): 18315-18322, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37997796

RESUMO

Reaction of complex [TpMe2Ir(η4-CH2C(Me)C(Me)C2)] (1) with a series of aromatic ketones at 130 °C renders, by means of a selective ortho-CH activation, Ir(III)-metallacycles 2-5, which display an Ir-H bond. When [TpMe2Ir(C6H5)2N2] (6) is treated with 2-(trifluoromethyl)acetophenone and 2-fluoroacetophenone at 80 °C, the formation of dimeric (7) and trimeric architectures (8) is achieved through the meta- and para-CH activation of the aromatic ketone, respectively. The generation of complexes 2-5 is proposed to occur by the initial formation of Ir(III) η1-ketone adducts as key intermediates, followed by aromatic CH activations and the release of a butadiene ligand. The formation of complexes 7 and 8 involves an assisted process in which a metal center activation of the less sterically hindered C-H bond of the aromatic ketone takes place (releasing a benzene molecule), followed by the coordination of the carbonyl group, which generates the respective dimeric and trimeric structures. Complexes 7 and 8 are efficient catalysts for the transfer hydrogenation of ketones and aldehydes using isopropanol as the hydrogen source. All complexes have been fully characterized by NMR spectroscopy, FT-IR, elemental analysis and, in the cases of 7 and 8, X-ray crystallography. Details of the reaction conditions, isolation of the products, and proposals for the pathways of formation of complexes 2-5 and 7-8 are discussed.

19.
Appl Opt ; 51(7): 780-8, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22410878

RESUMO

We perform a bidimensional analysis to evaluate the variation of the fluorescence decay of europium thenoyltrifluoroacetonate (EuTTA) with temperature changes. We analyze how a specific thermal distribution modifies the spatial temperature of the sensing film and we study the corresponding fluorescence response using an integral functional of the emission decay. We present experimental results of a thermal distribution registered with the EuTTA-based thermal-to-visible conversion method. Furthermore, we analyze the spatial and temporal response of the proposed sensing element by using heat-transfer theory. Based on the presented analysis, we establish the optimal thermal and physical design for the sensing element of the proposed thermal-to-visible converter.

20.
Dalton Trans ; 51(17): 6868-6875, 2022 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-35439809

RESUMO

Iodine promotes the in situ formation of iron(II) species from η4-vinylketene[Fe(CO)3] (3a-h) as a key intermediate for the synthesis of 2(5H)-furanones (4a-h) by a sequential water-insertion/carbon-oxygen coupling under mild reaction conditions. Compounds 4a-h were obtained in good to excellent yields. A possible reaction pathway was also proposed by DFT calculations. This methodology can be extended to the synthesis of (5H)-pyrrol-2-ones using anilines, with moderate yields and a few limitations.

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