218 research outputs found
Pd0-Catalyzed Intramoleculara-Arylation of Sulfones: Domino Reactions in the Synthesis of Functionalized Tetrahydroisoquinolines
A new strategy for the synthesis of tetrahydroisoquinolines based on the Pd(0)-catalyzed intramolecular α-arylation of sulfones is reported. The combination of this Pd-catalyzed reaction with intermolecular Michael and aza-Michael reactions allows the development of two- and three-step domino processes to synthesize diversely functionalized scaffolds from readily available starting materials. KEYWORDS: arylation; domino reactions; nitrogen heterocycles; palladium; sulfone
Auto-Tandem Catalysis in Ionic Liquids: Synthesis of 2-Oxazolidinones by Palladium-Catalyzed Oxidative Carbonylation of Propargylic Amines in EmimEtSO4
A convenient carbonylative approach to 2-oxazolidinone derivatives carried out using an Department of Chemistry, University of Parma, Parco Area delle Scienze 17/A, 43124 Parma, Italy; ionic liquid (1-ethyl-3-methylimidazolium nicola.ethyl sulfate, EmimEtSO4 ) as the solvent is presented. It is based on the sequential concatenation of two catalytic cycles, both catalyzed by the same metal species (auto-tandem catalysis): the first cycle corresponds to the oxidative monoaminocarbonylation of the triple bond of Received: propargylic 16 June 2016; amines Accepted: to give 5 July 2016; the Published: corresponding date 2-ynamide intermediates, while the second one involves the cyclocarbonylation of the latter to yield 2-(2-oxooxazolidin-5-ylidene)-acetamides. Abstract: A convenient carbonylative approach to 2-oxazolidinone derivatives carried out using an Reactions areionic carried liquid out (1-ethyl-3-methylimidazolium using a simple catalytic ethyl system sulfate, EmimEtSO4) consisting as ofthe PdI solvent2 in conjunction is presented. It is with an excess of KI, and thebased catalyst/solvent on the sequential system concatenation could of two be recycled catalytic cycles, several both catalyzed times without by the same appreciable metal species loss of activity (auto-tandem catalysis): the first cycle corresponds to the oxidative monoaminocarbonylation of the after extraction of the organic product with Et2 O
New Polymeric Films with Antibacterial Activity Obtained by UV-induced Copolymerization of Acryloyloxyalkyltriethylammonium Salts with 2- Hydroxyethyl Methacrylate
- Article on the development of new polymeric films with antibacterial activity obtained by UV-induced copolymerization of some polymerizable surfactants (acryloyloxyalkyltriethylammonium bromides, in particular) with commercially available 2-hydroxyethyl methacrylate
- Raw data
Abstract of the paper: New polymeric films with antibacterial activity have been prepared, by simple
UV-induced copolymerization of readily available omega-(acryloyloxy)-N,N,N-triethylalcan-1-aminium
bromides (or acryloyloxyalkyltriethylammonium bromides, AATEABs) with commercially available
2-hydroxyethyl methacrylate (HEMA), at different relative amounts. In particular, the antibacterial
activity of polymeric films derived from 11-(acryloyloxy)-N,N,N-triethylundecan-1-aminium
bromide (or acryloyloxyundecyltriethylammonium bromide, AUTEAB; bearing a C-11
alkyl chain linker between the acrylate polymerization function and the quaternary
ammonium moiety) and 12-(acryloyloxy)-N,N,N-triethyldodecan-1-aminium bromide (or
acryloyloxydodecyltriethylammonium bromide, ADTEB, bearing a C-12 alkyl chain linker) has
been assessed against Gram-negative Escherichia Coli and Gram-positive Staphylococcus aureus cells.
The results obtained have shown a clear concentration-dependent activity against both bacterial
strains, the films obtained from homopolymerization of pure AUTEAB and ADTEAB being the most
e ective. Moreover, ADTEAB-based films showed a higher antibacterial activity with respect to the
AUTEAB-based ones. Interestingly, however, both types of films presented a significant activity not
only toward Gram-positive S. aureus, but also toward Gram-negative E. Coli cells
Synthesis of Imidazolidin-2-ones and Imidazol-2-ones via Base-Catalyzed Intramolecular Hydroamidation of Propargylic Ureas under Ambient Conditions
The first organo-catalyzed synthesis of imidazolidin-2-ones and imidazol-2-ones via intramolecular hydroamidation of propargylic ureas is reported. The phosphazene base BEMP turned out to be the most active organo-catalyst compared with guanidine and amidine bases. Excellent chemo- and regioselectivities to five-membered cyclic ureas have been achieved under ambient conditions, with a wide substrate scope and exceptionally short reaction times (down to 1 min). A base-mediated isomerization step to an allenamide intermediate is the most feasible reaction pathway to give imidazol-2-ones, as suggested by DFT studies
10th Anniversary of Catalysts: Molecular Catalysis
On the occasion of this Special Issue, I would like to present an editorial message on this good occasion [...
Heme oxygenase-1 posttranslational modifications in the brain of subjects with Alzheimer disease and mild cognitive impairment. Free Radic.
a b s t r a c t Alzheimer disease (AD) is a neurodegenerative disorder characterized by progressive cognitive impairment and neuropathology. Oxidative and nitrosative stress plays a principal role in the pathogenesis of AD. The induction of the heme oxygenase-1/biliverdin reductase-A (HO-1/BVR-A) system in the brain represents one of the earliest mechanisms activated by cells to counteract the noxious effects of increased reactive oxygen species and reactive nitrogen species. Although initially proposed as a neuroprotective system in AD brain, the HO-1/BVR-A pathophysiological features are under debate. We previously reported alterations in BVR activity along with decreased phosphorylation and increased oxidative/nitrosative posttranslational modifications in the brain of subjects with AD and those with mild cognitive impairment (MCI). Furthermore, other groups proposed the observed increase in HO-1 in AD brain as a possible neurotoxic mechanism. Here we provide new insights about HO-1 in the brain of subjects with AD and MCI, the latter condition being the transitional phase between normal aging and early AD. HO-1 protein levels were significantly increased in the hippocampus of AD subjects, whereas HO-2 protein levels were significantly decreased in both AD and MCI hippocampi. In addition, significant increases in Ser-residue phosphorylation together with increased oxidative posttranslational modifications were found in the hippocampus of AD subjects. Interestingly, despite the lack of oxidative stressinduced AD neuropathology in cerebellum, HO-1 demonstrated increased Ser-residue phosphorylation and oxidative posttranslational modifications in this brain area, suggesting HO-1 as a target of oxidative damage even in the cerebellum. The significance of these findings is profound and opens new avenues into the comprehension of the role of HO-1 in the pathogenesis of AD. & 2012 Elsevier Inc. All rights reserved. Introduction Increased oxidative and nitrosative stress represents one of the main mechanisms involved in the pathogenesis of neurodegenerative disorders such as Alzheimer disease (AD), which exhibits a large impairment of neuronal structure and molecular pathways due to oxidative stress-induced posttranslational modifications on both proteins and lipids AD is an age-related neurodegenerative disorder characterized histopathologically by the presence of senile plaques, neurofibrillary tangles (NFTs), and synapse loss in selected brain region
Clostridioides difficile Infection in an Italian Tertiary Care University Hospital: A Retrospective Analysis
Clostridioides difficile infection (CDI) is a significant cause of morbidity and mortality, mostly in frail patients. Notification is not mandatory in Italy, and data on incidence, risk of death, and recurrence are lacking. The purpose of this study was to determine CDI incidence and risk factors for mortality and recurrence. The "ICD-9 00845" code in hospital-standardized discharged forms (H-SDF) and microbiology datasets were used to retrieve CDI cases at Policlinico Hospital, Palermo between 2013 and 2022. Incidence, ward distribution, recurrence rate, mortality, and coding rate were considered. The risk of death and recurrence was predicted through multivariable analysis. There were 275 CDIs, 75% hospital-acquired, the median time between admission and diagnosis was 13 days, and the median stay was 21 days. Incidence increased from 0.3 to 5.6% (an 18.7-fold increase) throughout the decade. Only 48.1% of cases were coded in H-SDF. The rate of severe/severe-complicated cases increased 1.9 times. Fidaxomicin was used in 17.1% and 24.7% of cases overall and since 2019. Overall and attributable mortalities were 11.3% and 4.7%, respectively. Median time between diagnosis and death was 11 days, and recurrence rate was 4%. Bezlotoxumab was administered in 64% of recurrences. Multivariable analysis revealed that only hemodialysis was associated with mortality. No statistically significant association in predicting recurrence risk emerged. We advocate for CDI notification to become mandatory and recommend coding CDI diagnosis in H-SDF to aid in infection rate monitoring. Maximum attention should be paid to preventing people on hemodialysis from getting CDI
Tuberomics: a molecular profiling for the adaption of edible fungi (Tuber magnatum Pico) to different natural environments
Background: Truffles are symbiotic fungi that develop underground in association with plant roots, forming ectomycorrhizae. They are primarily known for the organoleptic qualities of their hypogeous fruiting bodies. Primarily, Tuber magnatum Pico is a greatly appreciated truffle species mainly distributed in Italy and Balkans. Its price and features are mostly depending on its geographical origin. However, the genetic variation within T. magnatum has been only partially investigated as well as its adaptation to several environments.
Results: Here, we applied an integrated omic strategy to T. magnatum fruiting bodies collected during several
seasons from three different areas located in the North, Center and South of Italy, with the aim to distinguish them according to molecular and biochemical traits and to verify the impact of several environments on these properties. With the proteomic approach based on two-dimensional electrophoresis (2-DE) followed by mass spectrometry, we were able to identify proteins specifically linked to the sample origin. We further associated the proteomic results to an RNA-seq profiling, which confirmed the possibility to differentiate samples according to their source and provided a basis for the detailed analysis of genes involved in sulfur metabolism. Finally, geographical specificities were associated with the set of volatile compounds produced by the fruiting bodies, as quantitatively and qualitatively determined through proton transfer reaction-mass spectrometry (PTR-MS) and gas-chromatography mass spectrometry (GC-MS). In particular, a partial least squares-discriminant analysis (PLS-DA) model built from the
latter data was able to return high confidence predictions of sample source.
Conclusions: Results provide a characterization of white fruiting bodies by a wide range of different molecules, suggesting the role for specific compounds in the responses and adaptation to distinct environments
Exclusive Papers of the Editorial Board Members and Topical Advisory Panel Members of Catalysts in Section “Catalysis in Organic and Polymer Chemistry
Beta-Blocker Use in Older Hospitalized Patients Affected by Heart Failure and Chronic Obstructive Pulmonary Disease: An Italian Survey From the REPOSI Register
Beta (β)-blockers (BB) are useful in reducing morbidity and mortality in patients with heart failure (HF) and concomitant chronic obstructive pulmonary disease (COPD). Nevertheless, the use of BBs could induce bronchoconstriction due to β2-blockade. For this reason, both the ESC and GOLD guidelines strongly suggest the use of selective β1-BB in patients with HF and COPD. However, low adherence to guidelines was observed in multiple clinical settings. The aim of the study was to investigate the BBs use in older patients affected by HF and COPD, recorded in the REPOSI register. Of 942 patients affected by HF, 47.1% were treated with BBs. The use of BBs was significantly lower in patients with HF and COPD than in patients affected by HF alone, both at admission and at discharge (admission, 36.9% vs. 51.3%; discharge, 38.0% vs. 51.7%). In addition, no further BB users were found at discharge. The probability to being treated with a BB was significantly lower in patients with HF also affected by COPD (adj. OR, 95% CI: 0.50, 0.37-0.67), while the diagnosis of COPD was not associated with the choice of selective β1-BB (adj. OR, 95% CI: 1.33, 0.76-2.34). Despite clear recommendations by clinical guidelines, a significant underuse of BBs was also observed after hospital discharge. In COPD affected patients, physicians unreasonably reject BBs use, rather than choosing a β1-BB. The expected improvement of the BB prescriptions after hospitalization was not observed. A multidisciplinary approach among hospital physicians, general practitioners, and pharmacologists should be carried out for better drug management and adherence to guideline recommendations
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