Wyniki wyszukiwania - Biblioteka Nauki

1

Fluoryzujące barwniki pochodne kumaryny

100%

Czajkowski W. , Kaźmierska M.

Przemysł Chemiczny

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2002

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tom T. 81, nr 3

177-180

2

Synthesis, Characterization and Biological Evaluation of 4-Methyl-7-(salicylidineamino)coumarin Metal(II) Complexes

100%

El-Husseiny A. F.

Polish Journal of Chemistry

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2009

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tom Vol. 83, nr 10

1745-1755

EN

Four transition M(II) complexes [where M = Cu(II), Zn(II), Cd(II) and Pd(II)] of the organic ligand, 4-methyl-7-(salicylidineamino)coumarin, HL, have been synthesized and characterized by a variety of physicochemical techniques. An octahedral structure is proposed for Cd(II) complex, a tetrahedral structure for the Zn(II) complex while square planar for Pd(II) complex. Thermal decomposition study of the ligand and its metal complexes was monitored by TG and DTG analyses under N2 atmosphere. The decomposition course and steps were analyzed and the activation parameters of the nonisothermal de composition are determined. The negative values of Delta S* indicated the ordered structures of the prepared complexes compared to their starting reactants. The ligand HL and its metal complexes exhibited good antibacterial activities against Escherichia coli and Bacillus subtilis species.

3

Photocatalytic performance of titania nanospheres deposited on graphene in coumarin oxidation reaction

100%

Wojtoniszak M. , Zielinska B. , Kalenczuk R. J. , Mijowska E.

Materials Science Poland

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2012

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tom Vol. 30, No. 1

32--38

EN

In this paper, we present a study on enhanced photocatalytic performance of TiO2 nanospheres deposited on graphene (n-TiO2-G) in a process of coumarin oxidation. The enhancement of the photoactivity has been observed in respect to commercial TiO2 P25. The presented material was prepared in two steps: (i) hydrolysis of titanium (IV) butoxide (TBT) in ethanol solution with simultaneous deposition on graphene oxide (GO) and (ii) calcination of TiO2-GO to form anatase-TiO2 and reduce GO to graphene. The nanomaterial was characterized by transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), Fourier-Transformed Infrared spectroscopy and Raman spectroscopy. In the presented photocatalytic process the fluorescence was used to detect-OH formed on a photo-illuminated n-TiO2-G surface using coumarin which readily reacted with -OH to produce highly fluorescent 7-hydroxycoumarin.

4

Quantum chemical studies on the molecular structure, spectroscopic and electronic properties of (6-Methoxy-2-oxo-2H-chromen-4-yl)-methyl pyrrolidine-1-carbodithioate

88%

Evecen M. , Tanak H.

Materials Science Poland

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2016

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tom Vol. 34, No. 4

886--904

EN

In this paper, the molecular geometry, vibrational frequencies and chemical shifts of (6-Methoxy-2-oxo-2H-chromen-4-yl)methyl pyrrolidine-1-carbodithioate in the ground state have been calculated using the Hartree-Fock and density functional methods with the 6-311++G(d,p) basis set. To investigate the nonlinear optical properties of the title compound, the polarizability and the first hyperpolarizability were calculated. The conformational properties of the molecule have been determined by analyzing molecular energy properties. Using the time dependent density functional theory, electronic absorption spectra have been calculated. Frontier molecular orbitals, natural bond orbitals, natural atomic charges and thermodynamical parameters were also investigated by using the density functional theory calculations.

5

The Influence of Fluorine Substitution on Diels-Alder Reaction of 3-Vinylcoumarin and Ethylene

88%

Koroniak H. , Pasikowska M. , Fiedorow P.

Polish Journal of Chemistry

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2003

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tom Vol. 77 / nr 11

1523-1528

EN

Density Functional Theory (DFT) has been applied to study the concerted mechanism of the Diels-Alder reaction between 3-vinylcoumarin and ethylene, as well as their fluorinated analogues. The main goal was to establish the fluorine influence on reactivity and structure of transition state (TS) and predict the reaction path. Computations were performed at the B3LYP/6-31G* level, which allowed to optimise the structure of reactants and products.

6

Influence of phosphorohydrazone derivatives of benzopyrones on polymerization and viscosity of fibrin

75%

Michalska M. , Pajak W. , Kolodziejska J. , Lazarenkow A. , Nawrot-Modranka J.

Acta Biochimica Polonica

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2008

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tom 55

|

nr 3

613-617

EN

The synthesis and antitumour and antibacterial activity of coumarin and chromone phosphorohydrazones have been reported. This study describes influence of phosphorohydrazones derivatives of coumarin and chromone on the polymerization and viscosity of fibrin. The fibrin polymerization assay was performed by the Shen and Lorand method and the clot viscosity was measured on the basis of Shen and Lorand and Marchi and coworkers methods. Among the eight compounds tested, one coumarin derivative and two chromone derivatives showed significant activity

7

Administration of warfarin accelerates the recovery in ischemia/reperfusion-induced acute pancreatitis

75%

Maduzia D. , Ceranowicz P. , Cieszkowski J. , Chmura A. , Galazka K. , Kusnierz-Cabala B. , Warzecha Z.

Journal of Physiology and Pharmacology

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2020

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tom 71

|

nr 3

8

Analysis of Saussurea species from tibet using HPLC-DAD-ESI-MS n

75%

Dawa Z. , Zhou Y. , Bai Y. , Gesang S. , Liang J. , Ding L.

Acta Chromatographica

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2010

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tom Vol. 22, no. 1

141--152

EN

An HPLC-DAD-ESI-MS n method has been developed for simultaneous quantification of eight major compounds in eight Saussurea species which have long been used as the traditional Tibetan medicines. The method was validated for sensitivity, precision, and accuracy. LODs were from 0.11 to 5.01 μg mL -1, overall intra-day and inter-day variation was less than 2.70%, and overall recovery was over 98.0%. The correlation coefficients ( r 2) of the calibration plots were >0.991. This newly established method was successfully used to reveal difference among the chemical profiles and analytes contents of eight Saussurea species collected in Tibet. In addition, by comparison of UV and mass spectra with those of authentic compounds, a total of fifteen peaks were identified. It can be concluded that this is an effective method for quantification and evaluation of the flavonoids and coumarins in the eight species of the genus Saussurea . It can be used as an efficient reference method for development and use of the eight traditional Tibetan medicines by comparing their different characteristics.

9

Model studies on the properties of reaction site in hydrophobically modified polymers. I. Effect of cyclodextrins on photochemistry of coumarin 120

75%

Nowakowska M. , Smoluch M. , Sendor D.

Zeszyty Naukowe. Chemia / Politechnika Śląska

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2001

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tom z. 146

311-314

EN

The effect of alpha-, beta- and gamma-cyclodextrin, as a model for the hydrophobic reaction sites in microheterogenous polymeric systems, on the photochemical stability of 7-amino-4-methylcoumarin (C 120) was studied. Using spectroscopic techniques combined with HPLC analysis it was demonstrated that addition of beta-cyclodextrin to the aqueous solution of C 120 markedly inhibits the photodegradation of that dye. This was explained by taking into account the possiblity of the formation of an inclusion complex between C 120 and beta-cyclodextrin.

10

Influence of phosphorohydrazone derivatives of benzopyrones on polymerization and viscosity of fibrin

75%

Michalska M. , Pająk W. , Kołodziejska J. , Łazarenkow A. , Nawrot-Modranka J.

Acta Biochimica Polonica

|

2008

|

tom 55

|

nr 3

613-617

EN

The synthesis and antitumour and antibacterial activity of coumarin and chromone phosphorohydrazones have been reported. This study describes influence of phosphorohydrazones derivatives of coumarin and chromone on the polymerization and viscosity of fibrin. The fibrin polymerization assay was performed by the Shen and Lorand method and the clot viscosity was measured on the basis of Shen and Lorand and Marchi and coworkers methods. Among the eight compounds tested, one coumarin derivative and two chromone derivatives showed significant activity.

11

Chromatographical analysis of phenolic compounds in herb Convolvulus arvensis L.

75%

Krzaczek T. , Gogucka-Kocka A. , Ryn D.

|

nr 3-4

EN

Field bindweed (Convolvulus arvensis L.) has an impressive array of survival techniques, due to which it has become one of the worst weeds. This persistent field darnel is native to Eurasia but has spread to many parts of the world. TLC and HPLC were applied to carry out qualitative and quantitative determination of polyphenols compounds in bindweed, such as coumarins and phenolic acids: free and liberated by acid and alkaline hydrolysis. We identified and confirmed umbelliferone and scopoletin in the coumaries fraction. In the fraction of phenolic acids we noticed the occurrence of protocatechuic, caffeic, chlorogenic, gentisic, p-coumaric, p-hydroxybenzoic, p-hydroxyphenylo- acetic, ferulic, vanillic and salicylic. The caffeic (31.24 mg%), vanillic (5.8 mg%) and protocatechuic (4.62 mg%) acids were found to be the dominant compounds in the analysed plant.

PL

Convolvulus arvensis L. (powój polny) to wieloletnie pnącze o dużych zdolnościach adaptacyjnych. Pochodzi z Eurazji, a występuje niemal na całym świecie z wyjątkiem strefy okolorównikowej. Do identyfikacji jakościowej i ilościowej związków polifenolowych, takich jak kumaryny i kwasy fenolowe (wolne i uwolnione w wyniku hydrolizy kwasowej i zasadowej) zastosowano metody TLC i HPLC. Zidentyfikowano i potwierdzono obecność umbeliferonu i skopoletyny. We frakcji kwasów fenolowych potwierdzono występowanie kwasu kawowego. Pozostałe kwasy, tj. protokatecho- wy, gentyzowy, p-hydroksybenzoesowy, p-kumarowy, syryngowy, wanilinowy, ferulowy, p-hydrok- syfenylooctowy, chlorogenowy i salicylowy, zidentyfikowano po raz pierwszy. Metodą HPLC określono zawartość 7 fenolokwasów. Kwas kawowy (31,24mg%), wanilinowy (5.8mg%) i protokatechowy (4.62mg9o) byty dominującymi kwasami w badanej roślinie.

12

Influence of the extraction mode and type of eluents on the isolation of coumarins from plant material

75%

Kozyra M. , Glowniak K.

Herba Polonica

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2006

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tom 52

|

nr 4

EN

Coumarins are very common biologically active compounds that have been found in numerous species of the family Apiaceae. The biological and pharmacological activity of these substances has very interesting properties. Coumarins also play a major role in the plant defence system. The quality and quantity of furano- and piranocoumarins is important for a defensive role in a plant as these compounds form a barier between the environment and plant organs. In order to study the plant defence mechanism it is necessary to carry out a qualitative and quantitative analysis of both furano- and pyranocoumarins. In this paper the studies on the optimum extraction and their influence on the yield of furano- and pyranocoumarins from fruits of the species Peucedanum verticillare are reported. The coumarins were analysed quantitatively by a combined method of SPE and RP-HPLC.

PL

Związki kumarynowe są dość rozpowszechnioną w świecie roślinnym grupą metabolitów wtórnych, pochodnych benzo-a-pironu. Zainteresowanie badaczy tymi substancjami wynika z ich wszechstronnej aktywności biologicznej oraz szerokiego zastosowania w lecznictwie. Przeprowadzono optymalizację warunków ekstrakcji piranokumaryn w rozpuszczalnikach o różnej polarności (n-heptan, dichlorometan, metanol), na łaźni wodnej w temperaturze wrzenia rozpuszczalnika i na łaźni ultradźwiękowej przez 24 oraz 48 godzin. Po zakończeniu ekstrakcji roztwory badano metodą SPE RP-HPLC. Po 24 godzinach prowadzenia ekstrakcji zaobserwowano wyraźny (dwukrotny) wzrost zawartości kumaryn w badanych wyciągach. Polarność rozpuszczalnika ma wpływ na efektywność ekstrakcji poszczególnych związków: w wypadku imperatoryny, która tylko w śladowych ilościach ekstrahuje się z metanolu, dobrymi rozpuszczalnikami okazały się dichlorometan oraz n-heptan. Piranokumaryny natomiast dobrze ekstrahują się w metanolu i dichlorometanie. Ekstrakcja na łaźni ultradźwiękowej to krótsza i bardziej skuteczna metoda ekstrakcji niż ekstrakcja na łaźni wodnej w temperaturze wrzenia rozpuszczalnika.

13

Pochodne kumaryny stosowane w detekcji enzymów

63%

Wyrębska Ł.

Barwniki, Środki Pomocnicze

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2011

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tom nr 1-2

21-26

PL

W artykule przedstawiono przegląd pochodnych kumaryny stosowanych w nowoczesnych metodach detekcji enzymów, ze szczególnym uwzględnieniem analizy produktów żywnościowych. Opisano również metodykę syntezy wybranych związków z tej grupy.

EN

In this article are presented review of coumarin derivatives applied in novel methods of enzymes' detection, with particular taking into consideration analysis of food products. Here is also described synthesis of selected compounds belong to this group.

14

Synteza i kopolimeryzacja monomerów metakrylowych zawierających pierścienie kumarynowe i ftalimidowe

63%

Stępień I. , Bogdał D.

Czasopismo Techniczne. Chemia

|

2004

|

tom R. 101, z. 1-Ch

141-146

PL

Opracowano metody syntezy monomerów metakrylanu N-(2-ftalimidolilo) etylu (FEM) oraz 7-dietyloamino-3-(2-metakryloiloetoksy)karbonylokumary (MK), na drodze kondensacji Knoevenagela i metody aktywowanych estrów. Wszystkie reakcje przeprowadzono tak, aby charakteryzowały się prostotą ich przeprowadzania oraz małą ilością etapów pośrednich. Następnie monomery kopolimeryzowano tak, aby otrzymać polimer (FEM% MK) o molowej zawartości monomeru kumarynowego 0,5, 1, 2, 8%.

EN

Methods of synthesis, such as Knoevenagela condensation and active esters metod, of N-(2-phtalimidazolyl)ethyl methacrylate (FEM) and 7-diethyl-aminocoumarin-3-carbo-xylic acid 2-(methacryloyloxy)ethyl ester (MK) were developed. All reactions were carried out in a manner to reduce reaction times and decrease number of intermediate stages. Monomers were copolymerized to give (99.5:0.5), (99:1), (98:2), and (92:8 mol/mol) FEM%MK copolymers.

15

Apoptosis induction of human peripheral blood lymphocytes by naturally occurring coumarins

63%

Kocki J. , Bogucka-Kocka A.

Polish Journal of Environmental Studies

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2004

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tom 13

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nr Suppl.2, Part 1

EN

Our studies show the influence of coumarins: xanthotoxin and o,o-dimethyl-fraxetin on apoptosis in human peripheral blood lymphocytes in vitro. Lymphocytes (derived by ethical protocol) were cultured for 72 h in vivo. The cell cultures were stimulated with xanthotoxin or o,o-dimethyl-fraxetin in various concentrations. Apoptotic cells (compaction and margination of nuclear chromatin, cytoplasmic condensation, membrane blebbing and cell shrinkage) were observed in BX41 fluorescent Olympus microscope and recorded by MultiScan software. We observed the highest induction of apoptosis in cells stimulated with xanthotoxin in doses ≥50 μM in 48-hrs-cultures.

16

Photo- and electroluminescent properties of methacrylates containing carbazole and coumarin pendant groups

63%

Bogdał D. , Stępień I. , Sanetra J.

Polish Journal of Chemical Technology

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2003

|

tom Vol. 5, nr 3

93-95

EN

Conjugated polymer electroluminescence (EL) and photoluminescence (PL) is an integral part of optoelectonic science. It attracts more and more interest, which reflects in many applications such as LEDs, lighting, indicators, and displays. This kind of polymers is also used in liquid crystals and organic nonlinear optical materials, as well as some of them are expected to be small monochromatic passively addressed displays such as: mobile phones, and possibly backlights for liquid crystals displays. 2-(9-carbazolyl)ethyl methacrylate (CEM) and 7-diethyl-aminocoumarin-3-carboxylic acid 2-(methacry-loyloxy)ethyl ester (MK) were synthesized and then copolymerised to give (99.5:0.5), (99:1), (98:2), and (92:8 mol/mol) CEM/MK copolymers. The physical examinations for absorption and photo- and electroluminescence were conducted, and confirmed that these polymers should be used in opto-electronic industry.

17

Nowa metoda rozdzielania składników oraz oznaczania kumaryny w napojach alkoholowych i w maceratach z turówki wonnej (hierochloe odorata) z wykorzystaniem RP-HPLC i przepływu zwrotnego eluentu w kolumnie

63%

Skrzypczak A. , Kamiński M.

Camera Separatoria

|

2011

|

tom Vol. 3, No. 2

319--327

PL

Kumaryna (1,2-benzopiron) jest naturalną substancją występującą w roślinach stosowanych jako dodatki smakowe i aromatyczne do napojów alkoholowych. W wyniku pojawienia się doniesień o toksyczności kumaryny, ograniczono wykorzystanie ekstraktów roślinnych zawierających ją jako dodatek do żywności i napojów. Ustalono, że maksymalny poziom zawartości kumaryny, bezpieczny dla ludzi w żywności i napojach bezalkoholowych, wynosi 2 mg/kg, a w napojach alkoholowych wynosi 10 mg/kg. Biorąc pod uwagę powyższe, niezwykle ważne jest dysponowanie szybką i selektywną metodą oznaczania zawartości kumaryny zarówno w napojach alkoholowych, jak i w maceratach turówki wonnej, stosowanych do produkcji smakowych napojów alkoholowych. Praca prezentuje wyniki badań nad warunkami rozdzielania i oznaczania kumaryny w napojach alkoholowych i maceratach z turówki wonnej wykorzystywanych do produkcji wódek ziołowych. Warunki analityczne dobrano w ten sposób, by zapewnić optymalną selektywność rozdzielania w jak najkrótszym czasie. W tym celu zastosowano odwrócony układ faz RP-HPLC oraz detektor UV-DAD.

EN

The Coumarin (1.2 benzopiron) is a natural substance occurring in plants which is used as a flavor and an aroma of alcoholic beverages. As a result of reports concerning toxicity of the coumarin, the use of the plants extracts, which were food and beverages additives is reduced. It was established that the maximum content of coumarin, safe for human use in food and soft drinks is 2 mg/kg, in alcoholic drinks is 10 mg/kg. Given the above, it is very important to possess a rapid and selective method for the determination of coumarin in the flavoured alcoholic beverages, as well as macerates of Hierochloe odorata used to produce the alcoholic beverages. This paper presents results of research on the conditions of separation and determination of coumarin in alcoholic beverages and macerates of the sweet grass used for the production of herbal vodka. Analytical conditions were defined to ensure optimum selectivity of separation in the shortest possible time. For this purpose, the reversed phase RP-HPLC and UV-DAD detector, were used.

18

Właściwości i zastosowanie pochodnych 2H-1-benzopiran-2-onu jako związków pochodzenia naturalnego

63%

Czarna M. , Kamińska I. , Ortyl J.

Technical Issues

|

2015

|

tom nr 3

11--17

EN

This article is a detailed literature overview about properties and wide application of coumarin derivatives, whose representative is 2H-1-benzopyran-2-one. It turns out that this compounds can be found in many places all around the world. Huge part of them is already isolated and synthesized in laboratory conditions, however there are assumptions that many of them are not known at all and they might have an influence on science development. Considering to the structural variety of coumarin, its derivatives are characterized by different properties, what reflects numerous possibilities of their application and also attracts the interest of the world of science.

19

Flavonoids and coumarins from Hieracium pilosella L. [Asteraceae]

63%

Gawronska-Grzywacz M. , Krzaczek T.

Acta Societatis Botanicorum Poloniae

|

2009

|

tom 78

|

nr 3

189-195

EN

Typical chromatographic methods were successfully applied to isolate nine flavonoid compounds and two coumarin glycosides from the inflorescences and the herb of Hieracium pilosella L. Repeated column chromatography, occasionally paper chromatography and recrystallization made the separation of three flavonoid aglycones and six glycosides - possible. Coumarin glycosides were isolated by preparative thin layer chromatography. Subsequent UV, NMR and MS analyses have led to identification of the following flavonoid derivatives: known for the species - apigenin, luteolin, luteolin 7-O- ß-glucopyranoside, luteolin 4’-O-ß-glucopyranoside, isoetin 7-O-ß- -glucopyranoside, isoetin 4’-O-ß-glucuronide and new for the species – kaempferol 3-methyl ether and apigenin 7-O-ß-glucopyranoside. Third isoetin glycoside contained two different sugar moieties: xylose and glucose, probably attached to the hydroxyl groups at C-4’ or C-4’ and C-2’(or 5’) of an aglycone. Umbelliferone 7-O-ß-glucopyranoside (skimmin) and new for the genus Hieracium esculetin 7-O-ß-glucopyranoside (cichoriin) were determined by NMR and MS methods.

20

Pochodne kumaryny do roli molekularnych sensorów fluorescencyjnych do zastosowań w naukach life science

63%

Czarna M. , Kamińska I. , Ortyl J.

Technical Issues

|

2015

|

tom nr 4

3--10

EN

Fluorescent spectroscopy is an important method in life science which has recently gained popularity. Fluorescent spectroscopy is widely used for example by the researches in the variety of biological structures, intercellular interactions, various kinds of biomolecules and also for understanding of the biochemical processes which take place inside the living organisms. For this purpose, an application of fluorescent sensors and searching for more efficient and more sensitive fluorophore for illustrating, labelling and detection, have become a developing trend in biochemistry, medicine, biology and also in many other chemistry researches. Nowadays, issues which are connected to fluorescence are mainly applied to the newest achievements in the field of fluorescent methods and measurement techniques and also to the development and applications of fluorescent probes, what is closely showed up in this article.