14 research outputs found
Palladium(II)-Catalyzed annulation between ortho-alkenylphenols and allenes. Key role of the metal geometry in determining the reaction outcome
2-Alkenylphenols react with allenes, upon treatment with catalytic amounts of Pd(II) and Cu(II), to give benzoxepine products in high yields and with very good regio- and diastereoselectivities. This contrasts with the results obtained with Rh catalysts, which provided chromene-like products through a pathway involving a β-hydrogen elimination step. Computational studies suggest that the square planar geometry of the palladium is critical to favor the reductive elimination process required for the formation of the oxepine productsThis work was supported by the Spanish MINECO (grant:SAF2013-41943-R), the ERDF, the European Research Council (Advanced Grant No. 340055) and the Xunta de
Galicia (grants: GRC2013-041 and 2015-CP082). We also thank the orfeo-cinqa CTQ2014-51912-REDC. K.P.D.R. thanks the Coordenaça̧o de Aperfeiçoamento de Pessoal de ̧Nıvel Superior (CAPES, Brazil) for the Ph.D scholarship. We ́thank Dr. M. Martınez for XRD analysis. All calculations were ́carried out at Centro de Supercomputación de Galicia (CESGA
American College of Rheumatology Provisional Criteria for Clinically Relevant Improvement in Children and Adolescents With Childhood-Onset Systemic Lupus Erythematosus
10.1002/acr.23834ARTHRITIS CARE & RESEARCH715579-59
Palladium(II)-Catalyzed Annulation between <i>ortho</i>-Alkenylphenols and Allenes. Key Role of the Metal Geometry in Determining the Reaction Outcome
2-Alkenylphenols
react with allenes, upon treatment with catalytic
amounts of Pd(II) and Cu(II), to give benzoxepine products in high
yields and with very good regio- and diastereoselectivities. This
contrasts with the results obtained with Rh catalysts, which provided
chromene-like products through a pathway involving a β-hydrogen
elimination step. Computational studies suggest that the square planar
geometry of the palladium is critical to favor the reductive elimination
process required for the formation of the oxepine products
Separation of New Naphthoxazole Derivatives of Lapachol by High-Speed Counter-Current Chromatography
<div><p>This work describes the use of high-speed counter-current chromatography as an efficient and economic method in the separation and purification of new naphthoxazolic heterocyclic derivatives from lapachol (<b>1</b>), a naturally occurring naphtoquinone from different species of <i>Tabebuia</i>. A series of naphthoxazoles was obtained by nucleophilic condensation of lapachol (<b>1</b>) with aromatic aldehydes in ammonium medium. Each reaction led to the formation of two main products, derivatives from β-xyloidone, and the naphthoxazoles with the isoprenyl side chain of lapachol (<b>1</b>). Reaction products were purified by counter-current chromatography, using hexane–acetonitrile–methanol (2:2:1, v/v/v) as a non-aqueous solvent system.</p></div
Naphthoquinone Derivatives as Scaffold to Develop New Drugs for Tuberculosis Treatment
Despite being a curable disease, tuberculosis (TB) remains a public health problem worldwide mainly due to lengthy treatment, as well as its toxic effects, TB/HIV co-infection and the emergence of resistant Mycobacterium tuberculosis strains. These barriers reinforcing the need for development of new antimicrobial agents, that ideally should reduce the time of treatment and be active against susceptible and resistant strains. Quinones are compounds found in natural sources and among them, the naphthoquinones show antifungal, antiparasitic, and antimycobacterial activity. Thus, we evaluated the potential antimycobacterial activity of six 1,4-naphthoquinones derivatives. We determined the minimum inhibitory concentration (MIC) of the compounds against three M. tuberculosis strains: a pan-susceptible H37Rv (ATCC 27294); one mono-resistant to isoniazid (ATCC 35822); and one mono-resistant to rifampicin (ATCC 35838); the cytotoxicity in the J774A.1 (ATCC TIB-67) macrophage lineage; performed in silico analysis about absorption, distribution, metabolism, and excretion (ADME) and docking sites. All evaluated naphthoquinones were active against the three strains with MIC between 206.6 and 12.5 μM, and the compounds with lower MIC values have also showed low cytotoxicity. Moreover, two naphthoquinones derivatives 5 and 6 probably do not exhibit cross resistance with isoniazid and rifampicin, respectively, and regarding ADME analysis, no compound violated the Lipinski’s rule-of-five. Considering the set of findings in this study, we conclude that these naphthoquinones could be promising scaffolds to develop new therapeutic strategies to TB
American college of rheumatology provisional criteria for clinically relevant improvement in children and adolescents with childhood-onset systemic Lupus erythematosus
To develop a Childhood Lupus Improvement Index (CHILI) as a tool to measure response to therapy in childhood-onset systemic lupus erythematosus (cSLE), with a focus on clinically relevant improvement (CRIcSLE). Methods Pediatric nephrology and rheumatology subspecialists (n = 213) experienced in cSLE management were invited to define CRIcSLE and rate a total of 433 unique patient profiles for the presence/absence of CRIcSLE. Patient profiles included the following cSLE core response variables (CRVs): global assessment of patient well-being (patient-global), physician assessment of cSLE activity (MD-global), disease activity index score (here, we used the Systemic Lupus Erythematosus Disease Activity Index), urine protein-to-creatinine ratio, and Child Health Questionnaire physical summary score. Percentage and absolute changes in these cSLE-CRVs (baseline versus follow-up) were considered in order to develop candidate algorithms and validate their performance (sensitivity, specificity, area under the receiver operating characteristic curve [AUC]; range 0-1). Results During an international consensus conference, unanimous agreement on a definition of CRIcSLE was achieved; cSLE experts (n = 13) concurred (100%) that the preferred CHILI algorithm considers absolute changes in the cSLE-CRVs. After transformation to a range of 0-100, a CHILI score of >= 54 had outstanding accuracy for identifying CRIcSLE (AUC 0.93, sensitivity 81.1%, and specificity 84.2%). CHILI scores also reflect minor, moderate, and major improvement for values exceeding 15, 68, and 92, respectively (all AUC >= 0.92, sensitivity >= 93.1%, and specificity >= 73.4%). Conclusion The CHILI is a new, seemingly highly accurate index for measuring CRI in cSLE over time. This index is useful to categorize the degree of response to therapy in children and adolescents with cSLE.715579590CNPQ - Conselho Nacional de Desenvolvimento Científico e TecnológicoFAPESP – Fundação de Amparo à Pesquisa Do Estado De São Paulo303422/2015-7; 7/2016-9; 304255/2015-7215/03756-
HACEK infective endocarditis: characteristics and outcomes from a large, multi-national cohort.
The HACEK organisms (Haemophilus species, Aggregatibacter species, Cardiobacterium hominis, Eikenella corrodens, and Kingella species) are rare causes of infective endocarditis (IE). The objective of this study is to describe the clinical characteristics and outcomes of patients with HACEK endocarditis (HE) in a large multi-national cohort. Patients hospitalized with definite or possible infective endocarditis by the International Collaboration on Endocarditis Prospective Cohort Study in 64 hospitals from 28 countries were included and characteristics of HE patients compared with IE due to other pathogens. Of 5591 patients enrolled, 77 (1.4%) had HE. HE was associated with a younger age (47 vs. 61 years; p<0.001), a higher prevalence of immunologic/vascular manifestations (32% vs. 20%; p<0.008) and stroke (25% vs. 17% p = 0.05) but a lower prevalence of congestive heart failure (15% vs. 30%; p = 0.004), death in-hospital (4% vs. 18%; p = 0.001) or after 1 year follow-up (6% vs. 20%; p = 0.01) than IE due to other pathogens (n = 5514). On multivariable analysis, stroke was associated with mitral valve vegetations (OR 3.60; CI 1.34-9.65; p<0.01) and younger age (OR 0.62; CI 0.49-0.90; p<0.01). The overall outcome of HE was excellent with the in-hospital mortality (4%) significantly better than for non-HE (18%; p<0.001). Prosthetic valve endocarditis was more common in HE (35%) than non-HE (24%). The outcome of prosthetic valve and native valve HE was excellent whether treated medically or with surgery. Current treatment is very successful for the management of both native valve prosthetic valve HE but further studies are needed to determine why HE has a predilection for younger people and to cause stroke. The small number of patients and observational design limit inferences on treatment strategies. Self selection of study sites limits epidemiological inferences
Impact of early valve surgery on outcome of staphylococcus aureus prosthetic valve infective endocarditis: Analysis in the international collaboration of endocarditis-prospective cohort study
Background. The impact of early valve surgery (EVS) on the outcome of Staphylococcus aureus (SA) prosthetic valve infective endocarditis (PVIE) is unresolved. The objective of this study was to evaluate the association between EVS, performed within the first 60 days of hospitalization, and outcome of SA PVIE within the International Collaboration on Endocarditis-Prospective Cohort Study. Methods. Participants were enrolled between June 2000 and December 2006. Cox proportional hazards modeling that included surgery as a time-dependent covariate and propensity adjustment for likelihood to receive cardiac surgery was used to evaluate the impact of EVS and 1-year all-cause mortality on patients with definite left-sided S. aureus PVIE and no history of injection drug use. Results. EVS was performed in 74 of the 168 (44.3%) patients. One-year mortality was significantly higher among patients with S. aureus PVIE than in patients with non-S. aureus PVIE (48.2% vs 32.9%; P = .003). Staphylococcus aureus PVIE patients who underwent EVS had a significantly lower 1-year mortality rate (33.8% vs 59.1%; P = .001). In multivariate, propensity-adjusted models, EVS was not associated with 1-year mortality (risk ratio, 0.67 [95% confidence interval, .39-1.15]; P = .15). Conclusions. In this prospective, multinational cohort of patients with S. aureus PVIE, EVS was not associated with reduced 1-year mortality. The decision to pursue EVS should be individualized for each patient, based upon infection-specific characteristics rather than solely upon the microbiology of the infection causing PVIE
Impact of early valve surgery on outcome of staphylococcus aureus prosthetic valve infective endocarditis: Analysis in the international collaboration of endocarditis-prospective cohort study
Background. The impact of early valve surgery (EVS) on the outcome of Staphylococcus aureus (SA) prosthetic valve infective endocarditis (PVIE) is unresolved. The objective of this study was to evaluate the association between EVS, performed within the first 60 days of hospitalization, and outcome of SA PVIE within the International Collaboration on Endocarditis-Prospective Cohort Study. Methods. Participants were enrolled between June 2000 and December 2006. Cox proportional hazards modeling that included surgery as a time-dependent covariate and propensity adjustment for likelihood to receive cardiac surgery was used to evaluate the impact of EVS and 1-year all-cause mortality on patients with definite left-sided S. aureus PVIE and no history of injection drug use. Results. EVS was performed in 74 of the 168 (44.3%) patients. One-year mortality was significantly higher among patients with S. aureus PVIE than in patients with non-S. aureus PVIE (48.2% vs 32.9%; P = .003). Staphylococcus aureus PVIE patients who underwent EVS had a significantly lower 1-year mortality rate (33.8% vs 59.1%; P = .001). In multivariate, propensity-adjusted models, EVS was not associated with 1-year mortality (risk ratio, 0.67 [95% confidence interval, .39-1.15]; P = .15). Conclusions. In this prospective, multinational cohort of patients with S. aureus PVIE, EVS was not associated with reduced 1-year mortality. The decision to pursue EVS should be individualized for each patient, based upon infection-specific characteristics rather than solely upon the microbiology of the infection causing PVIE