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991.
Antonio Da Settimo Giampaolo Primofiore Federico Da Settimo Francesca Simorini Anna Maria Marini Concettina La Motta Sabrina Taliani 《Journal of heterocyclic chemistry》2000,37(2):373-377
The preparation of a novel purine containing heterocyclic ring system, indolotriazinopurine, by the condensation of 8‐hydrazinotheophylline with 5‐substituted isatins via the intermediate hemiaminal and hydrazone derivatives, is described. 相似文献
992.
Joanna Izabela Lachowicz Luigi Isaia Lecca Federico Meloni Marcello Campagna 《Molecules (Basel, Switzerland)》2021,26(21)
An increasing number of pathologies correlates with both toxic and essential metal ions dyshomeostasis. Next to known genetic disorders (e.g., Wilson’s Disease and β-Thalassemia) other pathological states such as neurodegeneration and diabetes are characterized by an imbalance of essential metal ions. Metal ions can enter the human body from the surrounding environment in the form of free metal ions or metal-nanoparticles, and successively translocate to different tissues, where they are accumulated and develop distinct pathologies. There are no characteristic symptoms of metal intoxication, and the exact diagnosis is still difficult. In this review, we present metal-related pathologies with the most common onsets, biomarkers of metal intoxication, and proper techniques of metal qualitative and quantitative analysis. We discuss the possible role of drugs with metal-chelating ability in metal dyshomeostasis, and present recent advances in therapies of metal-related diseases. 相似文献
993.
An investigation was carried out on the preparation of highly disordered samples of MgCl2 (in delta -form), starting from different Mg-alkyls and chlorinating agents. Successively we studied which kind of silica carrier had to be preferred and which treatment was strictly' necessary to achieve a qualified catalyst precursor showing outstanding performance. Different routes were investigated to support the active, disordered MgCl2 on the silica carrier and then some following ways to complete the catalyst. The final result of this investigation was the synthesis of a catalyst showing the best performance with reference to the parameters of use in every polymerization process. It has to be e.g. mentioned: — high yield, referred to the residual content of Mg, Ti and Cl; — no activity decrease when operating at a very high hydrogen concentration; — possibility to polymerize also at elevated temperatures; — very high isotactic index and stereoregular structure, as measured by the NMR technique; — possibility to reach high MFR (Melt Flow Rate) (up to 400 g IPP/10 min at 230°C, 2,16 kg, ASTM D 1238L); — outstanding morphology and flowability. 相似文献
994.
Carmela Gerardi Loris Pinto Federico Baruzzi Giovanna Giovinazzo 《Molecules (Basel, Switzerland)》2021,26(19)
Wine pomace has attracted the attention of the food industry, due to its high content in bioactive compounds, and its multiple healthy activities. In this work, whole and separated skin pomaces from fermented (red) and un-fermented (white) grape by-products were characterized for their antioxidant and antimicrobial activities in order to exploit them as functional food ingredient. Antioxidant activity, measured by both ORAC and TEAC assays, was higher in whole than in skin pomace extracts. The characterization of phenolic composition in whole and skin pomace extracts confirmed the peculiarity of some compounds such as anthocyanins (107.84 + 10.3 mg/g TP) in red skin pomace and a great amount of flavanols (80.73 + 4.04 mg/g TP) in white skin pomace. Whole and skin pomace extracts displayed the same antibacterial activity at 250 µg gallic acid equivalents (GAE)/mL. Red and white skin pomace extracts showed a Minimum Inhibitory Concentration (MIC) of 31.25–62.5 GAE/mL against Staphylococcus aureus and Enterococcus faecalis. Pseudomonas spp. were more sensitive to red skin pomace extracts rather than white skin pomace extracts. Given these results, both red and white pomace extracts could be exploited for future application in food, pharmaceutical and cosmetic industry. 相似文献
995.
Valeria Poggetti Silvia Salerno Emma Baglini Elisabetta Barresi Federico Da Settimo Sabrina Taliani 《Molecules (Basel, Switzerland)》2022,27(8)
Carbonic anhydrases (CAs) are a family of ubiquitous metal enzymes catalyzing the reversible conversion of CO2 and H2O to HCO3− with the release of a proton. They play an important role in pH regulation and in the balance of body fluids and are involved in several functions such as homeostasis regulation and cellular respiration. For these reasons, they have been studied as targets for the development of agents for treating several pathologies. CA inhibitors have been used in therapy for a long time, especially as diuretics and for the treatment of glaucoma, and are being investigated for application in other pathologies including obesity, cancer, and epilepsy. On the contrary, CAs activators are still poorly studied. They are proposed to act as additional (other than histidine) proton shuttles in the rate-limiting step of the CA catalytic cycle, which is the generation of the active hydroxylated enzyme. Recent studies highlight the involvement of CAs activation in brain processes essential for the transmission of neuronal signals, suggesting CAs activation might represent a potential therapeutic approach for the treatment of Alzheimer’s disease and other conditions characterized by memory impairment and cognitive problems. Actually, some compounds able to activate CAs have been identified and proposed to potentially resolve problems related to neurodegeneration. This review reports on the primary literature regarding the potential of CA activators for treating neurodegeneration-related diseases. 相似文献
996.
Merlín Rosales Beatriz Alvarado Federico Arrieta Carlos De La Cruz Ángel González Karely Molina Otto Soto Yslamar Salazar 《Polyhedron》2008
The synthesis and solid-state IR, 1H and 31P{1H} NMR spectroscopic characterization of complexes of the type MH(CO)(κ3-OCOR)(PPh3)2 [M = Ru, Os; R = CH3, CH2Cl, C6H5 and CH(CH3)2] are reported in this paper. These compounds were obtained by reaction of the respective cationic complex [MH(CO)(NCMe)2(PPh3)2]BF4 with the sodium salt of the corresponding carboxylic acid in a 1:1 v/v dichloromethane/methanol solution at room temperature. The spectroscopic data of these complexes and some DFT calculations reveal an octahedral geometry with a bidentated carboxylate, two equivalent triphenylphosphines in a mutually trans positions, a linear hydride and a linear carbonyl both in the cis-positions of the coordination sphere. The catalytic results indicate that these complexes are efficient and regioselective precatalysts for the quinoline hydrogenation and for the hydroformylation of 1-hexene, under mild reaction conditions (130 °C and 4 atm H2 and 120 °C and 15 atm H2/CO, respectively). For benzothiophene hydrogenation, the osmium complexes showed low activities whereas the analogous ruthenium complexes were catalytically inactive under somewhat more drastic reaction conditions to those of the quinoline hydrogenation (140 °C and 10 atm H2). 相似文献
997.
Cosimo Alejandro Cavalieri Federico J. Cardona Alberto Brüls Olivier 《Nonlinear dynamics》2020,102(4):1997-2016
Nonlinear Dynamics - The classical local impact laws of Newton and Poisson are able to capture the behaviour observed in single-impact collisions in many situations. However, in the case of... 相似文献
998.
Salvatore Federico 《International Journal of Non》2012,47(2):273-284
This work aims at obtaining a covariant representation of the elasticity tensor of a hyperelastic material when the elastic strain energy potential is written employing the volumetric–distortional decomposition of the deformation. This requires the careful definition of some fundamental fourth-order tensors: the identity, the spherical operator, and the deviatoric operator, which appear in the material and spatial expressions of the elasticity tensor. These operators can be defined in the spatial or the material setting and admit pulled-back and pushed-forward forms, respectively. These forms are intimately related to the pulled-back and pushed-forward metric tensors, and are somewhat awkward to derive in Cartesian coordinates, because of the loss of the distinction between a vector space and its dual, and therefore between objects having contravariant and covariant components, which obey to different transformation laws. The relationship between the deformation and the various forms of the identity, spherical, and deviatoric operators can be entirely clarified only within a covariant theory, where the central role played by the spatial and material metric tensors, and their pulled-back and pushed-forward counterparts, which are deformation tensors, can be emphasised. 相似文献
999.
Federico Nguyen 《中国物理C(英文版)》2010,34(6):795-800
Studies of γγ interactions are performed with the KLOE detector,without tagging of the outgoing e+e-.The data sample is from an integrated luminosity of 240 pb-1.It was collected at the φ-factory DAΦNE with e+e-beams colliding at s~(1/2) 1 GeV,below the φ resonance peak.We present preliminary results concerning the observation of the γγ→η process and the evidence for γγ→π0π0 production at low π0π0 invariant masses. 相似文献
1000.
Federico Da Settimo Anna Maria Marini Gianluca Pardi Giampaolo Primofiore Silvia Salerno Francesca Simorini 《Journal of heterocyclic chemistry》2001,38(3):607-612
A new synthetic route to build the [1,2,4]triazino[3,4‐ f]purine nucleus is described. The novel [1,2,4]‐triazino[3,4‐ f]purine‐4,6,8(l H,7 H,9 H)‐trione derivatives were obtained by condensation of 8‐hydrazinotheophylline with appropriate glyoxylic acids via the intermediate hydrazones. 相似文献