Log in

Relevant bibliographies by topics / Hydroxycoumarins / Journal articles

To see the other types of publications on this topic, follow the link: Hydroxycoumarins.

Journal articles on the topic 'Hydroxycoumarins'

Author: Grafiati

Published: 4 June 2021

Last updated: 25 July 2025

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'Hydroxycoumarins.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Bhuyan, Pulak, Sinki Kolita, Leema Dutta, and Pankaj Das. "One-Pot Synthesis of Unsymmetrical Bis(4-Hydroxycoumarin-3-yl)methanes." Synlett 28, no. 17 (2017): 2291–94. http://dx.doi.org/10.1055/s-0036-1589065.

Full text

Abstract:

Unsymmetrical bis(4-hydroxycoumarin-3-yl)methane derivatives have been synthesized from 4-hydroxycoumarins, aldehydes, and secondary amines via 3-(aminoalkyl)-4-hydroxycoumarin intermediates, followed by substitution.

APA, Harvard, Vancouver, ISO, and other styles

2

Traven, Valery F., Larisa I. Vorobjeva, Tatjana A. Chibisova, Edward Andrew Carberry, and Noelle Jean Beyer. "Electronic absorption spectra and structure of hydroxycoumarin derivatives and their ionized forms." Canadian Journal of Chemistry 75, no. 4 (1997): 365–76. http://dx.doi.org/10.1139/v97-042.

Full text

Abstract:

Electronic absorption spectra of 18 hydroxycoumarin derivatives and their ionized forms have been studied. Close agreement between experimental and the PPP CI calculated electron absorption band energies has been found in most cases. Strong polarization of the carbonyl function of the pyrone ring in the 7-hydroxycoumarin derivatives, H-bonding between the hydroxyl group and neighboring substituent in the ortho-substituted hydroxycoumarins, as well as their tautomeric transformations, have been suggested in the discussion of the electronic absorption spectra of the hydroxycoumarin derivatives.

APA, Harvard, Vancouver, ISO, and other styles

3

Anary-Abbasinejad, Mohammad, Hossein Anaraki-Ardakani, Azimeh Saidipoor, and Mahmood Shojaee. "Synthesis of 3-[(acetylamino)(aryl)methyl]-4-Hydroxycoumarins." Journal of Chemical Research 2007, no. 9 (2007): 535–37. http://dx.doi.org/10.3184/030823407x247785.

Full text

Abstract:

One-pot, three-component reaction between aryl aldehydes, 4-hydroxycoumarin, and acetonitrile in the presence of chlorosulfonic acid affords 3-[(acetylamino)(aryl)methyl]-4-hydroxycoumarins in excellent yields.

APA, Harvard, Vancouver, ISO, and other styles

4

Wu, Nan, Xinnian Li, Xin Xu, and Daqing Shi. "Synthesis of 3,3′-arylmethylidenebis-4-hydroxycoumarin derivatives catalysed by KF-montmorillonite." Journal of Chemical Research 2007, no. 10 (2007): 561–62. http://dx.doi.org/10.3184/030823407x255551a.

Full text

Abstract:

3,3′-Arylmethylidenebis-4-hydroxycoumarins derivatives have been synthesised in good yields by the Michael addition reaction of aromatic aldehydes with 4-hydroxycoumarin in DMF catalysed by KF-montmorillonite.

APA, Harvard, Vancouver, ISO, and other styles

5

ALOK, KUMAR MITRA, DE APARNA, KARCHAUDHURI NILAY, KUMAR MISRA SWAPAN, and KUMAR MUKHOPADHYAY APURBA. "Synthesis of Coumarins in Search of Better Nonpeptidic HIV Protease Inhibitors." Journal of Indian Chemical Society Vol. 75, Oct-Dec 1998 (1998): 666–71. https://doi.org/10.5281/zenodo.5916038.

Full text

Abstract:

Department of Chemistry, University of Calcutta, 92, Acharya Prafulla Chandra Road, Calcutta-700 009 <em>Manuscript received 7 August 1998</em> 3-Substituted-4-hydroxycoumarins have been recently identified as active nonpeptidic HIV protease inhibitors. In order to get more potent inhibitors, synthesis of a number of 3-substituted-4-hydroxycoumarins have been designed. Nucleophilicity of C-3 in 4- hydroxycoum arin is exploited by reacting with an electrophile 3-carbethoxycoumarin to achieve a new C-3 substituted-4-hydroxycoumarin. But the product identified is a benzopyranodicoumarin (2), whic

APA, Harvard, Vancouver, ISO, and other styles

6

Anary-Abbasinejad, Mohammad, Khadijeh Charkhati, and Alireza Hassanabadi. "Stereoselective synthesis of 3-[2-(dialkoxyphosphoryl)-1,2-dialkoxycarbonyl-ethyl]-4-hydroxycoumarins by reaction between trialkyl phosphites, dialkyl acetylenedicarboxylates and 4-hydroxycoumarin." Journal of Chemical Research 2009, no. 5 (2009): 319–21. http://dx.doi.org/10.3184/030823409x450435.

Full text

Abstract:

A three-component reaction between trialkyl phosphites, dialkyl acetylenedicarboxylates and 4-hydroxycoumarin is described as a simple and efficient route for the synthesis of 3-[2-(dialkoxyphosphoryl)-1,2-dialkoxycarbonyl-ethyl]-4-hydroxycoumarins in high yields.

APA, Harvard, Vancouver, ISO, and other styles

7

Yoon, Jeong A., and Young Taek Han. "Efficient Synthesis of Pyrido[3,2-c]coumarins via Silver Nitrate Catalyzed Cycloisomerization and Application to the First Synthesis of Polyneomarline C." Synthesis 51, no. 24 (2019): 4611–18. http://dx.doi.org/10.1055/s-0037-1610730.

Full text

Abstract:

Herein, we report an efficient method for the synthesis of the pyrido[3,2-c]coumarin scaffold, one of the privileged heterocycle-fused coumarin scaffolds, via a AgNO3-catalyzed cycloisomerization of 4-(propynylamino)coumarins obtained from diverse 4-hydroxycoumarins. This concise method affords pyrido[3,2-c]coumarin analogues bearing diverse substituents on the benzene or pyridine ring in moderate to good yields. Moreover, this methodology was extended to the facile synthesis of polyneomarline C, a natural pyrido[3,2-c]coumarin derivative isolated from the Chinese herbal medicine Polyalthia ne

APA, Harvard, Vancouver, ISO, and other styles

8

Kostova, Ivanka. "Hydroxycoumarins fromFraxinus ornusBark." Planta Medica 58, no. 05 (1992): 484. http://dx.doi.org/10.1055/s-2006-961529.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Timonen, Juri, Paula Aulaskari, Pipsa Hirva, and Pirjo Vainiotalo. "Negative Ion Electrospray Ionization Mass Spectrometry and Computational Studies on Substituted 7-Hydroxycoumarins." European Journal of Mass Spectrometry 15, no. 5 (2009): 595–603. http://dx.doi.org/10.1255/ejms.1019.

Full text

Abstract:

Twenty-two substituted 7-hydroxycoumarins were studied by negative ion electrospray ionization collision-induced dissociation (CID) mass spectrometry. Fragmentation pathways were also investigated by computation method using the B3LYP density functional theory. In general, the most important fragmentations of the 7-hydroxycoumarin [M – H]− ions were the elimination of CO2 and CO which agreed with the calculated energies of the proposed fragmentation reactions. In most cases, methyl group elimination was also favorable. Methyl group elimination occurred in three different ways, the most interes

APA, Harvard, Vancouver, ISO, and other styles

10

Datta, Mrityunjoy. "Synthesis of Linear 6-Allylated-7-hydroxycoumarins: para-Claisen Rearrangement of 2'-Allylated/Prenylated Derivatives of 4'-Prenyloxy Cinnamic Acid." Asian Journal of Chemistry 37, no. 1 (2024): 100–104. https://doi.org/10.14233/ajchem.2025.32937.

Full text

Abstract:

Linear 6-allylated-7-hydroxycoumarins were synthesized by the para-Claisen rearrangement of 4'-prenyloxy cinnamic acid derivatives under refluxing condition in N,N-diethylaniline. This method eliminates the requirement for an additional Lewis acid, such as boron trifluoride etherate or trichloride, to convert 7-alkoxycoumarins into 7-hydroxycoumarins, unlike alternative techniques.

APA, Harvard, Vancouver, ISO, and other styles

11

Sizov, A. Yu, A. F. Kolomiets, and A. F. Fokin. "3-Polyfluoroalkylthio-4-hydroxycoumarins." Journal of Fluorine Chemistry 58, no. 2-3 (1992): 342. http://dx.doi.org/10.1016/s0022-1139(00)80807-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Huitink, Geraldine M. "Studies of 7-hydroxycoumarins." Talanta 35, no. 12 (1988): 973–76. http://dx.doi.org/10.1016/0039-9140(88)80231-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Ganguly, Nemai C., Sanjoy Dutta, Mrityunjoy Datta, and Prithwiraj De. "Solid-state regioselective nitration of activated hydroxyaromatics and hydroxycoumarins with cerium (IV) ammonium nitrate." Journal of Chemical Research 2005, no. 11 (2005): 733–35. http://dx.doi.org/10.3184/030823405774909342.

Full text

Abstract:

Predominant ortho-selective mononitration of low-melting and liquid phenols and hydroxycoumarins in moderate to high yields has been accomplished upon grinding with solid cerium (IV) ammonium nitrate (CAN). Microwave-assisted expeditious CAN-mediated nitration of relatively high melting phenols and hydroxycoumarins with high efficiency and selectively under solvent-free conditions has been also developed to address the problems of sluggishness and low yield for these reluctant substrates.

APA, Harvard, Vancouver, ISO, and other styles

14

Guo, Tao, and Xu-Ning Wei. "Ammonium Iodide-Mediated Sulfenylation of 4-Hydroxycoumarins or 4-Hydroxyquinolinones with a Sulfonyl Chloride as a Sulfur Source." Synlett 28, no. 18 (2017): 2499–504. http://dx.doi.org/10.1055/s-0036-1589083.

Full text

Abstract:

A novel ammonium iodide-induced sulfenylation of 4-hydroxycoumarins or 4-hydroxyquinolinones by using an aryl- or alkylsulfonyl chloride as the sulfur source gave a wide range of 3-sulfanyl-4-hydroxycoumarins or 3-sulfanyl-4-hydroxyquinolinones, respectively, in moderate to good yields. This method provides as a simple approach to the direct formation of C–S bonds, which is of high value and utility in the pharmaceutical industry.

APA, Harvard, Vancouver, ISO, and other styles

15

P., C. Rath, H. Sabata B., and K. Rout M. "Merocyanines Derived from Substituted 4-Hydroxycoumarins. Part II. Determination of Relative Acidity." Journal of Indian Chemical Society Vol. 41 No. 12, Dec 1964 (2022): 803–8. https://doi.org/10.5281/zenodo.6516367.

Full text

Abstract:

The relative acidity of different 4-hydroxycoumarins has been determined by two methods: (\(i\)) by extension of the application of Forster's rule to the absorption data of \(p\)-diallrylaminobenzylidene derivatives of different 4-hydroxycoumarins and their sea analogues, (\(ii\)) by the application of Brooker's deviation factor. For evaluation by the second method, the absorption data of oxonols of different 4-hydroxycoumarins have been collected.

APA, Harvard, Vancouver, ISO, and other styles

16

Abrams, Barny. "Mono-Chlorinated 3-Carboxy-7-Hydroxycoumarin: A Highly Fluorescent and Water-Soluble Violet Excitable Dye for Cell Analysis." Blood 112, no. 11 (2008): 4929. http://dx.doi.org/10.1182/blood.v112.11.4929.4929.

Full text

Abstract:

Abstract In our search for new violet excitable dyes with improved photochemical properties, we examined several halogen substituted 7-hydroxycoumarins and found that chlorinated derivatives could be as bright as their fluorinated analogs. In particular, mono-chlorinated 3-carboxy-7-hydroxycoumarin (V450) has a quantum yield equal to 3-carboxy-6,8- difluoro-7-hydroxycoumarin (Pacific Blue™). Antibodies specific to various cell surface markers (CD3, CD4, CD45) were labeled with V450 and tested in single color flow cytometry assays. Our results show that conjugates of V450 are brighter than the

APA, Harvard, Vancouver, ISO, and other styles

17

Durand-Niconoff, J. Sergio, Erik Ortiz-Blanco, Gabriela Sosa-Ortiz, et al. "Mannich bases of hydroxycoumarins: synthesis, DFT/QTAIM computational study and assessment of biological activity." RSC Advances 11, no. 50 (2021): 31260–71. http://dx.doi.org/10.1039/d1ra04611j.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Facenda, Gracia, Miguel Real, Jose A. Galán-Pérez, Beatriz Gámiz, and Rafael Celis. "Soil Effects on the Bioactivity of Hydroxycoumarins as Plant Allelochemicals." Plants 12, no. 6 (2023): 1278. http://dx.doi.org/10.3390/plants12061278.

Full text

Abstract:

Soil plays a primary role in the activity of plant allelochemicals in natural and agricultural systems. In this work, we compared the phytotoxicity of three natural hydroxycoumarins (umbelliferone, esculetin, and scopoletin) to different model plant species (Lactuca sativa, Eruca sativa, and Hordeum vulgare) in Petri dishes, and then selected the most phytotoxic compound (umbelliferone) to assess how its adsorption and dissipation in two distinct soils affected the expression of its phytotoxic activity. The root growth inhibitory effect of umbelliferone was significantly greater than that of e

APA, Harvard, Vancouver, ISO, and other styles

19

Komissarenko, A. N., and V. N. Kovalev. "Hydroxycoumarins and flavones ofSecurigera securidaca." Chemistry of Natural Compounds 23, no. 2 (1987): 252. http://dx.doi.org/10.1007/bf00598775.

Full text

APA, Harvard, Vancouver, ISO, and other styles

20

Bulut, M., and Ç. Erk. "Improved synthesis of some hydroxycoumarins." Dyes and Pigments 30, no. 2 (1996): 99–104. http://dx.doi.org/10.1016/0143-7208(95)00060-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Liu, Chang-Ling, Miao Li, Ai-Ying Guan, Hong Zhang, and Zheng-Ming Li. "Design, Synthesis and Fungicidal Activity of Novel (E)-Methyl 2-{2-[(coumarin-7-yloxy)methyl]phenyl}-3-methoxyacrylates." Natural Product Communications 2, no. 8 (2007): 1934578X0700200. http://dx.doi.org/10.1177/1934578x0700200811.

Full text

Abstract:

A number of 7-hydroxycoumarins (5), on treatment with one equivalent of ( E)-methyl 2-{2-[(chloromethyl)phenyl]}-3-methoxyacrylate (6) at 80°C for 6–8 h, afforded ( E)-methyl 2-{2-[(coumarin-7-yloxy)methyl]phenyl}-3-methoxyacrylates (2) in 80–85% yields. The 7-hydroxycoumarins (5) were in turn prepared from resorcinols (3) and substituted ethyl 3-oxopropanoate (4). Subsequently, results of biological activities evaluated in the greenhouse indicated that several of these compounds have good fungicidal activity against cucumber downy mildew (CDM) at 25g ai/ha.

APA, Harvard, Vancouver, ISO, and other styles

22

Ozheredov, D. S., and P. A. Karpov. "Comparative analysis of allosteric rearrangements in FtsZ protein structure induced by benzamide and 4-hydroxycoumarine compounds." Faktori eksperimental'noi evolucii organizmiv 35 (September 25, 2024): 164–69. http://dx.doi.org/10.7124/feeo.v35.1679.

Full text

Abstract:

Aim. To reveal allosteric rearrangements of FtsZ molecules arising under the influence of benzamide compounds and 4-hydroxycoumarin derivatives. To discover the key molecular mechanisms predetermining the effect of the specified compounds on the cell division in bacteria. Methods. Comparative analysis of FtsZ protein structures and their complexes with ligands. Application of structural bioinformatics software for molecular visualization, measurement of interatomic distances and approximation of intramolecular shifts based on RMSD indicators. Results. Revealed conformational changes in FtsZ pr

APA, Harvard, Vancouver, ISO, and other styles

23

Pham, Quyen T., Phong Q. Le, Ha V. Dang, et al. "Iodine-mediated formal [3 + 2] annulation for synthesis of furocoumarin from oxime esters." RSC Advances 10, no. 72 (2020): 44332–38. http://dx.doi.org/10.1039/d0ra07566c.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

To, Tuong A., Yen H. Vo, Anh T. Nguyen, Anh N. Q. Phan, Thanh Truong, and Nam T. S. Phan. "A new route to substituted furocoumarins via copper-catalyzed cyclization between 4-hydroxycoumarins and ketoximes." Organic & Biomolecular Chemistry 16, no. 28 (2018): 5086–89. http://dx.doi.org/10.1039/c8ob01064a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Goka, Benjamin, and Douglas A. Klumpp. "Synthesis of warfarin analogs: conjugate addition reactions of alkenyl-substituted N-heterocycles with 4-hydroxycoumarin and related substrates." RSC Advances 13, no. 7 (2023): 4754–56. http://dx.doi.org/10.1039/d3ra00251a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Chen, Zi-cong, Lang Tong, Zhi-bo Du та ін. "Annulation of β-naphthols and 4-hydroxycoumarins with vinylsulfonium salts: synthesis of dihydrofuran derivatives". Organic & Biomolecular Chemistry 16, № 15 (2018): 2634–38. http://dx.doi.org/10.1039/c8ob00293b.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Bondarenko, S. P., M. S. Frasinyuk, and V. P. Khilya. "Aminomethylation of 3-aryl-7-hydroxycoumarins." Chemistry of Heterocyclic Compounds 46, no. 5 (2010): 529–35. http://dx.doi.org/10.1007/s10593-010-0541-y.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Shcherbakov, K. V., Ya V. Burgart, M. I. Kodess, and V. I. Saloutin. "Structure of 5,6,7,8-tetrafluoro-4-hydroxycoumarins." Chemistry of Heterocyclic Compounds 48, no. 9 (2012): 1297–306. http://dx.doi.org/10.1007/s10593-012-1136-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Serra, Silvia, Giulio Ferino, Maria João Matos, et al. "Hydroxycoumarins as selective MAO-B inhibitors." Bioorganic & Medicinal Chemistry Letters 22, no. 1 (2012): 258–61. http://dx.doi.org/10.1016/j.bmcl.2011.11.020.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Balalas, T., G. Stratidis, D. Papatheodorou, et al. "One-pot Synthesis of 2-Substituted 4H-Chromeno[3,4-d]oxazol-4-ones from 4-Hydroxy-3-nitrocoumarin and Acids in the Presence of Triphenylphosphine and Phosphorus Pentoxide under Microwave Irradiation." SynOpen 02, no. 02 (2018): 0105–13. http://dx.doi.org/10.1055/s-0036-1591977.

Full text

Abstract:

2-Substituted 4H-chromeno[3,4-d]oxazol-4-ones are prepared from 4-hydroxy-3-nitrocoumarin and acids by one-pot reaction in the presence of PPh3 and P2O5 under microwave irradiation or by one-pot two-step reactions in the presence of Pd/C and hydrogen and then P2O5 under microwave irradiation. The fused oxazolocoumarins were also synthesized from 3-amido-4-hydroxycoumarins and P2O5 under microwave irradiation. The 3-amido-4-hydroxycoumarins are obtained almost quantitatively from 4-hydroxy-3-nitrocoumarin, acids and PPh3 under microwave irradiation, or in the presence of Pd/C and H2 on heating.

APA, Harvard, Vancouver, ISO, and other styles

31

Zhou, Hui, Xinzhao Deng, Zhenjun Ma, et al. "Synthesis of furo[3,2-c]coumarin derivatives using visible-light-promoted radical alkyne insertion with bromocoumarins." Organic & Biomolecular Chemistry 14, no. 25 (2016): 6065–70. http://dx.doi.org/10.1039/c6ob00768f.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Kumaran, Subramani, Mohan Prabhakaran, Narayanan Mariyammal, and Kanniyappan Parthasarathy. "Catalyst-free 1,6-conjugate addition of indoles and 4-hydroxycoumarins to para-quinone methides: synthesis of unsymmetrical triarylmethanes." Organic & Biomolecular Chemistry 18, no. 39 (2020): 7837–41. http://dx.doi.org/10.1039/d0ob01789b.

Full text

APA, Harvard, Vancouver, ISO, and other styles

33

Rashid, Mohammad A., James A. Armstrong, Alexander I. Gray, and Peter G. Waterman. "Novel C-Geranyl 7-Hydroxycoumarins from the Aerial Parts of Eriostemon tomentellus." Zeitschrift für Naturforschung B 47, no. 2 (1992): 284–87. http://dx.doi.org/10.1515/znb-1992-0221.

Full text

Abstract:

From the aerial parts of Eriostemon tomentellus five coumarins have been isolated. These have been characterized as ostruthin (6-geranyl-7-hydroxycoumarin (1)) and the novel compounds, 8-geranyl-7-hydroxycoumarin (2), (E)-6-(7-hydroxy-3,7-dimethylocta-2,5-dienyl)- 7-hydroxycoumarin (3), (E)-6-(7-hydroperoxy-3,7-dimethylocta-2,5-dienyl)-7-hydroxycoumarin (4), and 6-(6-hydroxy-3,7-dimethylocta-2,7-dienyl)-7-hydroxycoumarin (5). In addition tembamide (2-{4-methoxyphenyl}-2-hydroxy-N-benzoylethylamine (6 ) was isolated and the l3C NMR spectrum reported for the first time.

APA, Harvard, Vancouver, ISO, and other styles

34

Hussain, Majid, Chuang Niu, and Guan-Wu Wang. "Palladium-catalyzed synthesis of [60]fullerene-fused furochromenones and further electrochemical functionalization." Organic Chemistry Frontiers 7, no. 10 (2020): 1249–54. http://dx.doi.org/10.1039/d0qo00264j.

Full text

Abstract:

The palladium-catalyzed heteroannulation of [60]fullerene with 4-hydroxycoumarins affords [60]fullerene-fused furochromenones, which can be further derivatized via an electrochemical method to synthesize 1,2,3,4-adducts.

APA, Harvard, Vancouver, ISO, and other styles

35

Zhang, Sheng-Ling, Zhi-Shu Huang, Lin-Kun An, et al. "Synthesis of Zwitterionic 4-Hydroxycoumarin Derivatives through a Unique Reaction of 4-Hydroxycoumarins withp- Benzoquinone and Pyridine." Organic Letters 6, no. 26 (2004): 4853–55. http://dx.doi.org/10.1021/ol048109p.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Majumdar, K. C., A. Biswas, and P. P. Mukhopadhyay. "SnCl4I2 mediated regioselective 6-endo- and 5-exo-cyclization of ortho-allylenols." Canadian Journal of Chemistry 83, no. 12 (2005): 2046–51. http://dx.doi.org/10.1139/v05-212.

Full text

Abstract:

3-Allyl-4-hydroxycoumarins and 4-allyl-3-hydroxycoumarins are obtained in 90%92% yields by the thermal [3,3] sigmatropic rearrangement of the corresponding ethers. 3-Allyl-4-hydroxy-6-methylpyrone is obtained from the direct alkylation of 4-hydroxy-6-methylpyrone with allyl halide. These substrates on treatment with SnCl4I2 at 25 °C give a mixture of both 5-exo- and 6-endo-cyclization products. However, regioselective formation of 5-exo products is observed when the reactions are conducted at lower temperatures (05 °C, kinetically controlled), while the reaction at a higher temperature (50

APA, Harvard, Vancouver, ISO, and other styles

37

Kausar, Nazia, Partha Pratim Ghosh, Gargi Pal, and Asish R. Das. "Graphene oxide nanosheets: a highly efficient and reusable carbocatalyst catalyzes the Michael-cyclization reactions of 4-hydroxycoumarins, 4-hydroxypyrone and 4-hydroxy-1-methylquinolinone with chalcone derivatives in aqueous media." RSC Advances 5, no. 74 (2015): 60199–207. http://dx.doi.org/10.1039/c5ra08776g.

Full text

Abstract:

Graphene oxide nanosheets: a highly efficient and reusable carbocatalyst catalyzes the Michael-cyclization reactions of 4-hydroxycoumarins, 4-hydroxypyrone and 4-hydroxy-1-methylquinolinone with chalcone derivatives in aqueous media.

APA, Harvard, Vancouver, ISO, and other styles

38

Sharma, Suraj, Bipul Sarma, and Gakul Baishya. "Direct synthesis of 4-hydroxycoumarins and 4-hydroxy-6-methyl-2-pyrone containing chroman-4-ones via a silver catalyzed radical cascade cyclization reaction." New Journal of Chemistry 45, no. 34 (2021): 15475–86. http://dx.doi.org/10.1039/d1nj03437e.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Yang, Zan, Yueqiao Yan, An Li, et al. "Iodine-mediated sulfenylation of 4-hydroxycoumarins with sulfonyl hydrazides under aqueous conditions." New Journal of Chemistry 42, no. 18 (2018): 14738–41. http://dx.doi.org/10.1039/c8nj03461c.

Full text

Abstract:

An efficient, metal-free approach to the synthesis of sulfenylated coumarins based on the iodine catalyzed regioselective sulfenylation of 4-hydroxycoumarins with arylsulfonyl hydrazides was developed under mild conditions in water.

APA, Harvard, Vancouver, ISO, and other styles

40

Berg, Marian de Boer-van den, Henk H. W. Thijssen, and Cees Vermeer. "The In Vivo Effects of Oral Anticoagulants in Man: Comparison Between Liver and Non-Hepatic Tissues." Thrombosis and Haemostasis 59, no. 02 (1988): 147–50. http://dx.doi.org/10.1055/s-0038-1642744.

Full text

Abstract:

SummaryThe in vivo effects of oral anticoagulant therapy with 4–hydroxycoumarins on various vitamin K–dependent enzyme systems in man were compared. In hepatic microsomes obtained from donors who has been treated with 4–hydroxycoumarins for more than 6 months, the vitamin K 2,3 epoxide reductase activity and the DTT–dependent vitamin K quinone reductase activity were diminished to 35% and 20% of the corresponding normal values. In the non–hepatic tissues, only a small decrease in vitamin K 2,3 epoxide reductase activity could be demonstrated, while no differences were found in the vitamin K qu

APA, Harvard, Vancouver, ISO, and other styles

41

Gong, Lingzhen, He Zhao, Jian Yang, Huanfeng Jiang, and Min Zhang. "Selective construction of fused heterocycles by an iridium-catalyzed reductive three-component annulation reaction." Chemical Communications 57, no. 67 (2021): 8292–95. http://dx.doi.org/10.1039/d1cc03332h.

Full text

Abstract:

Herein, we report a catalytic reductive three-component annulation reaction for the construction of fused heterocycles featuring a pyrano[2,3-b]pyridyl motif from N-heteroarenium salts and formaldehyde with cyclic 1,3-diketones or 4-hydroxycoumarins.

APA, Harvard, Vancouver, ISO, and other styles

42

Talekar, P. R. "Copper triflate catalysed synthesis of Coumarinophosphorothioates." International Journal of Advance and Applied Research 5, no. 23 (2024): 183–85. https://doi.org/10.5281/zenodo.13622067.

Full text

Abstract:

Abstract:  A new method was developed to prepare coumarino-phosphoro-thioates (2a-g) from 7-hydroxycoumarins (1a-g). This approach uses O, O-diethyl phosphorochloridothioate along, & employs copper triflate as the driving force...

APA, Harvard, Vancouver, ISO, and other styles

43

Iossifova, Tania, Ivanka Kostova, and Ljuba N. Evstatieva. "Secoiridoids and hydroxycoumarins in Bulgarian Fraxinus species." Biochemical Systematics and Ecology 25, no. 3 (1997): 271–74. http://dx.doi.org/10.1016/s0305-1978(97)00006-9.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Ghiami-Shomami, Ali, Mona Ashtari-Delivand, Bahram Ghalami-Choobar, and Ivo Leito. "Computational studies of acidities of some hydroxycoumarins." Computational and Theoretical Chemistry 1190 (November 2020): 113008. http://dx.doi.org/10.1016/j.comptc.2020.113008.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Smith, Gerald J., Roderick J. Weston, Ying Tang, Yinrong Lu, and Jolon M. Dyer. "Photoproducts of 7-Hydroxycoumarins in Aqueous Solution." Australian Journal of Chemistry 65, no. 10 (2012): 1451. http://dx.doi.org/10.1071/ch12292.

Full text

Abstract:

Near-UV irradiation of aqueous solutions of 7-hydroxy-6-methoxycoumarin (scopoletin) and 6,7-dihydroxycoumarin (esculetin) resulted in the formation of dimers. Substantially greater amounts of the 7-hydroxy-6-methoxycoumarin photodimer were produced compared with that of 6,7-dihydroxycoumarin. Fluorescence spectra indicated that the initial photolytic reaction involves the excited state of the phenolate form of the monomeric coumarin. The electro-spray ionization (ESI) mass spectrum suggested that the major product (with a sodiated quasimolecular ion at m/z 405) from the photolysis of scopolet

APA, Harvard, Vancouver, ISO, and other styles

46

Duong, Truc-Vi H., Todd S. Carroll, Daniel S. Bejan та Edward J. Valente. "β-Chain Hydrogen-Bonding in 4-Hydroxycoumarins". Journal of Chemical Crystallography 50, № 4 (2019): 387–99. http://dx.doi.org/10.1007/s10870-019-00813-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

47

Li, Hui-Yin, and George A. Boswell. "A facile synthesis of fluorinated 4-hydroxycoumarins." Tetrahedron Letters 37, no. 10 (1996): 1551–54. http://dx.doi.org/10.1016/0040-4039(96)00101-3.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Nykolov, Nykolay, Tanya Iossifova, Elka Vassileva, Ivanka Kostova, and Georgi Stoev. "Reverse-phase high pressure liquid chromatographic analysis of hydroxycoumarins in plant extracts. Quantitative determination of hydroxycoumarins inFraxinus ornus." Phytochemical Analysis 4, no. 2 (1993): 86–88. http://dx.doi.org/10.1002/pca.2800040207.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Raunio, Hannu, Olli Pentikäinen, and Risto O. Juvonen. "Coumarin-Based Profluorescent and Fluorescent Substrates for Determining Xenobiotic-Metabolizing Enzyme Activities In Vitro." International Journal of Molecular Sciences 21, no. 13 (2020): 4708. http://dx.doi.org/10.3390/ijms21134708.

Full text

Abstract:

in vivo methods, such as spectrophotometric, fluorometric, mass spectrometric,and radioactivity-based techniques. In fluorescence-based assays, the reaction produces a fluorescentproduct from a nonfluorescent substrate or vice versa. Fluorescence-based enzyme assays areusually highly sensitive and specific, allowing measurements on small specimens of tissues withlow enzyme activities. Fluorescence assays are also amenable to miniaturization of the reactionmixtures and can thus be done in high throughput. 7-Hydroxycoumarin and its derivatives arewidely used as fluorophores due to their desirabl

APA, Harvard, Vancouver, ISO, and other styles

50

K. Bandaru, Sravan, and Matthew C. Risi. "Zn(OAc)2.2H2O-Catalyzed C3-alkylation and O-alkylation of 4-Hydroxycoumarin derivatives." Caribbean Journal of Science and Technology 10, no. 02 (2022): 10–16. http://dx.doi.org/10.55434/cbi.2022.20102.

Full text

Abstract:

or the C3-alkylation and O-alkylation of 4-hydroxycoumarins with benzylic, allylic, and corresponding acetates, respectively, under neat conditions at 60 0C with high product yield, Zn(OAc)2.2H2O has been found to be an effective reusable solid superacid catalyst.

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!