Search results for "salen"

Antonio Galateo fra Salento ed Europa, in Graeci sumus et hoc nobis gloriae accedit. In memoria di Amleto Pallara

2016

L'articolo è incentrato sulla figura del medico e scrittore quattrocentesco Antonio De Ferrariis detto Antonio Galateo.

'Graeci sumus et hoc nobis gloriae accedit'. La grecità salentina di Antonio Galateo

2020

L'esperienza intellettuale di Galateo rappresenta una svolta importante nelle vicende culturali che collegarono e divisero le coste adriatiche e ioniche della Puglia e della Grecia tra il XV e il XVI secolo. Galateo's intellettual experience is an important turning point in the cultural events that linked and divided the Adriatic and Ioanian coasts of Puglia and Greece between the XV and XVI century.

Kompleksy manganu(III) z czterodonorowymi zasadami Schiffa

2008

Evaluation of furanocoumarins from seeds of the wild parsnip (Pastinaca sativa L. s.l.).

2018

Abstract Although the wild parsnip (Pastinaca sativa L. s.l.) fruits are known to contain linear and angular furanocoumarins, the individual components of the seeds have not been fully identified and quantitated, and, in the case of immature seeds, reported. In view of this, the main furanocoumarin compounds were extracted using pyridine, and were isolated using semi-preparative high-performance liquid chromatography. The structural elucidation of isolated compounds was done based on detailed spectral analysis conducted by liquid chromatography–electrospray ionization–mass spectrometry (LC–ESI/MS), 1H and 13C NMR and, where possible, by gas chromatography–mass spectrometry (GC–MS). The quan…

Metabolism of coumarin by precision-cut calf liver slices and calf liver microsomes.

1995

1. The metabolism of 50 microM [3-14C]coumarin has been studied in precision-cut-calf liver slices. 2. The metabolism of 50 microM coumarin to 7-hydroxycoumarin has also been examined in calf, rat, Cynomolgus monkey and human liver microsomal preparations. 3. In precision-cut calf liver slices, [3-14C]coumarin was metabolized to various polar products and to metabolite(s) that bound covalently to calf liver slice proteins. The polar products included 7-hydroxycoumarin (which was extensively conjugated with D-glucuronic acid and/or sulphate), metabolites of the 3-hydroxylation pathway (mainly o-hydroxyphenylethanol and o-hydroxyphenylacetic acid), and unknown metabolites. 4. Coumarin 7-hydro…

Inhibitory effects and oxidation of 6-methylcoumarin, 7-methylcoumarin and 7-formylcoumarin via human CYP2A6 and its mouse and pig orthologous enzymes

2015

1. Information about the metabolism of compounds is essential in drug discovery and development, risk assessment of chemicals and further development of predictive methods. 2. In vitro and in silico methods were applied to evaluate the metabolic and inhibitory properties of 6-methylcoumarin, 7-methylcoumarin and 7-formylcoumarin with human CYP2A6, mouse CYP2A5 and pig CYP2A19. 3. 6-Methylcoumarin was oxidized to fluorescent 7-hydroxy-6-methylcoumarin by CYP2A6 (Km: 0.64-0.91 µM; Vmax: 0.81-0.89 min(-1)) and by CYP2A5 and CYP2A19. The reaction was almost completely inhibited at 10 µM 7-methylcoumarin in liver microsomes of human and mouse, but in pig only 40% inhibition was obtained with the…

Ethylene/1-olefin copolymerization behaviour of vanadium and titanium complexes bearing salen-type ligand

2013

Ethylene/1-olefin copolymerization using vanadium and titanium complexes bearing tetradentate [O,N,N,O]-type ligand and EtAlCl2 or MAO as a cocatalyst is carried out. In the presence of the vanadium complex activated with EtAlCl2 is observed (a) negative “comonomer effect”, (b) high comonomer incorporation and narrow chemical composition distribution (CCD), (c) unexpected copolymer microstructure, and (d) increased molecular weight of copolymers when compared with the homopolymer. In contrast, titanium catalyst gives copolymers with lower 1-olefin content and broad CCD. Supported complexes show higher activity, lower 1-olefins incorporation and give copolymers with ultra high molecular weig…

Photochemical and Photobiological Studies of a Furonaphthopyranone as a Benzo-spaced Psoralen Analog in Cell-free and Cellular DNA

1997

Photobiological activities of the benzo-spaced psoralen analog furonaphthopyranone 3 have been investigated in cell-free and cellular DNA. The molecular geometry parameters of 3 suggest that it should not form interstrand crosslinks with DNA. With cell-free DNA no evidence for crosslinking but also not for monoadduct formation was obtained; rather, the unnatural furocoumarin 3 induces oxidative DNA modifications under near-UVA irradiation. The enzymatic assay of the photosensitized damage in cell-free PM2 DNA revealed the significant formation of lesions sensitive to formamidopyrimidine DNA glycosylase (Fpg protein). In the photooxidation of calf thymus DNA by the furonaphthopyranone 3, 0.2…

Dichlorovanadium (IV) complexes with salen-type ligands for ethylene polymerization

2008

Vanadium complexes with tetradentate salen-type ligands were first time explored in ethylene polymerizations. The effects of the vanadium complex structure, the alkyl aluminum cocatalysts type (EtAlCl2, Et2AlCl, Et3Al, and MAO), and the polymerization conditions (Al/V molar ratio, temperature) on polyethylene yield were explored. It was found that EtAlCl2 in conjunction with investigated vanadium complexes produced the most efficient catalytic systems. It was shown, moreover, that the structural changes of the tetradentate salen ligand (type of bridge which bond donor nitrogen atoms and type of substituent on aryl rings) affected activity of the catalytic system. The complexes containing li…

Ethylenebis(5-chlorosalicylideneiminato)vanadium dichloride immobilized on MgCl2 -based supports as a highly effective precursor for ethylene polymer…

2009

Ethylenebis(5-chlorosalicylideneiminato)vanadium dichloride supported on MgCl2(THF)2 or on the same carrier modified by EtnAlCl3−n, where n = 1–3, was used in ethylene polymerization in the presence of MAO or a common alkylaluminium compounds as a cocatalyst. The support type alter vanadium loading and also change the characteristic of the catalytic active sites. Et2AlCl is the best activator for a catalyst which has been immobilized on a nonmodified support, whereas the systems which contain a carrier which has been modified by an organoaluminium compound reveal the highest activity in conjunction with MAO. That difference, together with different temperature effects on polymerization effi…