- Spectroscopic and solution studies of some transition metal complexes of new 4-hydroxy coumarin semi- and thiosemicarbazone complexes
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Two new ligands, 4-hydroxy coumarin-3-thiosemicarbazone (H 2L1) and 4-hydroxy coumarin-3-semicarbazone (H 2L2) were synthesized and used for the preparation of a series of transition metal complexes (Cr3+, Co2+, Ni 2+, Cu2+, and Fe3+), derived from these ligands. These complexes have the forms [ML1Cl2]·nX (1-5) and [ML2Cl]·nX (6-9) (X = H2O or ethanol). The structures of these complexes were elucidated by elemental analyses, IR, UV-Vis, and electrical conductivity, as well as magnetic susceptibility measurements and thermal analyses. IR spectral data indicates that in all complexes, the ligands act as monobasic tridentate, coordinated through keto oxygen or sulfur, azomethine nitrogen and deprotonated phenolic oxygen atom. On the basis of other physicochemical investigations, tetrahedral or square planar geometries are assigned for Cu2+ complexes in monomeric structures. In the case of the Co2+, Ni2+ and Fe3+ complexes, octahedral stereochemistries in monomeric structures are suggested. The dissociation constants of the ligands and the stability constants of their Cu(II), Co(II), Ni(II), and Fe(III) complexes have been also determined using potentiometric pH-metric titration in mixed solvents of dioxane: H2O and DMF: H2O with different ratios and different temperatures.
- Mosa, Aisha I.,Ibrahim, Mohamed M.,Aldhlmani, Sharah A.
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- Development of novel chromeno[4,3-c]pyrazol-4(2H)-one derivates containing piperazine as inhibitors of PI3Kα
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PI3K pathway has been heavily studied and is one of the most potential targets for various cancer treatment. Herein, we designed and synthesized a series of novel chromeno[4,3-c]pyrazol-4(2H)-one derivates contained piperazine based on our previous resear
- Yin, Yong,Zhou, Yang,Sha, Shao,Wu, Xun,Wang, She-Feng,Qiao, Fang,Song, Zhong-Cheng,Zhu, Hai-Liang
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- A route to the synthesis of novel coumarins
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The 1:1:1 adduct which originates from the reaction of triphenylphosphine, dialkyl acetylenedicarboxylate, and 3-formyl-4-hydroxycoumarin undergoes an intramolecular Wittig reaction to provide a series of unique 2H,5H-pyrano[3,2-c][1]benzopyran-5-ones (pyranocoumarins). Springer-Verlag 2004.
- Rad-Moghadam, Kurosh,Mohseni, Mehdi
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- Identification of novel ROS inducer by merging the fragments of piperlongumine and dicoumarol
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A series of novel ROS inducers were designed by merging the fragments of piperlongumine and dicoumarol. Most of these derivatives showed potent in vitro activity against three cancer cell lines and good selectivity towards normal lung cells. The most pote
- Xu, Xiaojuan,Fang, Xia,Wang, Jun,Zhu, Hong
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- Synthesis, structural characterizations and spectroscopic properties of binuclear CoIII complex and its Schiff ligand as a chemosensor for fuorescent recognition of ZnII
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Binuclear CoIII complex [Co2(L)3(DMF)3] containing a Schiff ligand H2L was synthesized and analyzed by elemental analysis, single crystal X-ray crystallography, FT-IR, UV–Vis absorption spectroscopy,
- Ding, Wen-Min,Guo, Geng,Li, Juan,Sun, Yi-Gang,Sun, Yin-Xia
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- Synthesis and Docking Study of Novel Pyranocoumarin Derivatives
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Abstract: A new series of fused tricyclic coumarin derivatives were designed, synthesized by a simple and convenient method, starting from 4-hydroxycoumarin and virtually screened by molecular docking on the target protein 3FRZ (PDB ID: 3FRZ), a HCV RNA-dependent RNA polymerase, for potency against hepatitis C virus (HCV). Efficient binding to the target protein was found for most of the synthesized compounds.
- Karteek, S. Durga,Reddy, A. Gopi,Tej, M. Bhuvan,Rao, M. V. Basaveswara
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p. 272 - 282
(2021/04/02)
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- Molecular iodine mediated oxidative cleavage of the C-N bond of aryl and heteroaryl (dimethylamino)methyl groups into aldehydes
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The oxidative cleavage of the C-N bond of aryl and heteroaryl (dimethylamino)methyl groups is achieved by employing molecular iodine as a mild oxidizing agent under ambient conditions in the presence of a mild base. The important reaction of C3 formylation of free NH and substituted indoles containing various substituents is accomplished from the corresponding Mannich bases. This methodology can also be extended for the synthesis of aryl and other heteroaryl aldehydes and ketones. Furthermore, the usefulness of the method is successfully demonstrated on a gram scale.
- Mandrekar, Ketan S.,Tilve, Santosh G.
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supporting information
p. 4152 - 4155
(2021/03/15)
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- Synthesis and structure of Schiff bases derived from 3-formyl-4- hydroxycoumarin and diamines
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The mono- and diimine products from the condensation of 3-formyl-4-hydroxycoumarin and various diamines were synthesized. It was shown by 1H NMR and mass spectrometry that the obtained compounds in DMSO-d6 solution and in gas phase exist in the E- and Z-keto-enamine forms.
- Milevskii,Chibisova,Solov'Eva,Anisimova,Lebedev,Ivanov,Traven
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p. 1781 - 1792
(2013/07/26)
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- Ring transformation of chromone-3-carboxamide
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4-Hydroxycoumarin-3-carboxaldehyde (5) was obtained from chromone-3-carboxaldehyde (1) via chromone-3-carboxamide (2) and 3-aminomethylene-2H-chroman-2,4-dione (3). 3-Alkylaminomethylenechroman-2,4-diones (7,8) were obtained from the reaction of primary a
- Ibrahim, Magdy A.
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experimental part
p. 7687 - 7690
(2009/12/04)
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- New coumarin type dyes for optical data recording
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The present invention relates to new coumarin compounds and to their use as dyes in optical layers for optical data recording, preferably for optical data recording using a laser with a wavelength up to 450 nm. The invention further relates to an optical layer comprising said dyes and to a write only read many (WORM) type optical recording medium capable of recording and reproducing information with radiation of blue laser, which employs a coumarin type dye in the optical layer.
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Page/Page column 6
(2008/06/13)
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- Synthesis anti-fungal and anti-bacterial screening of 3-phenyl-1,4,5-trihydro-pyrazol and 2, 4-dihydro[1,2,4]-triazol-3-one derivatives of 4-hydroxy-2-oxo-2H-1-benzopyran
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4-Hydroxy-2-oxo-2H-1-benzopyran-3-carboxaldehydes 2a-d are prepared from 4-hydroxy-2-oxo-2H-1-benzopyrans 1a-d via the Vielsmeyer Haack reaction. The 4-hydroxy-2-oxo-3-(3′oxo-3′-phenylprop-1′-enyl)- 2H-1-benzopyrans 3a-d are obtained from 2a-d via the Cla
- Mulwad,Shirodkar, Jyoti M.
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p. 377 - 381
(2007/10/03)
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- Vilsmeier-Haack formylation of coumarin derivatives. A solvent dependent kinetic study
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A kinetic study of the reaction of coumarin derivatives with Vilsmeier-Haack (VH) reagent (1 : 1 DMF-POCl3) in various solvent media revealed second-order kinetics with a first-order in [Substrate] and first-order in [VH reagent]. The reaction rates altered nonlinearly with an increase in the dielectric constant of the medium and the data did not fit completely well with either Amis or Kirkwood's theories of ion-dipole and dipole-dipole type reactions. On the basis of kinetic and spectroscopic results, participation of VH-adduct and coumarin molecule in the rate limiting step, has been proposed. Kinetic and activation parameters have been evaluated and discussed in terms of isokinetic relationship and as a function of solvent compositions. Linearity of Leffler's and Exner's plots indicate a similar type of mechanism to be operative in different dielectric media at all temperatures.
- Rajanna,Solomon, Florence,Ali, Mir Moazzam,Sai Prakash
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p. 865 - 872
(2007/10/03)
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