• Journal of the Korean Society of Industry Convergence
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• v.6 no.2
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• pp.109-113
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• 2003

We report herein synthetic results obtained new types of crown ethers containing coumarin group. Crown ethers containing coumarin group 1~3 are hydroxymethyl-15-crown-5-ether linked with 4-hydroxy coumarin-4-acetic acid by esterification reaction. Crown ethers containing coumarin group 1~3 have different cavity in each crown ether rings. The 12-crown-4 ether with coumarin 1 has the smallest cavity size. The 15-crown-5 ether with coumarine 2 has the medium cavity size. The 18-crown-6 ether with coumarin 3 has the largest cavity size. Therefore each crown ether with coumarin group will recognize different ionic radius meta. Because of different hole size in crown ethers, these crown ethers seem to be had different selectivity in luminescent sensors. The crown ethers with coumarine 1~3 synthesized hydroxymethyl-15-crown-5-ether and 4-hydroxy coumarin-4-acetic acid same ratio at one to one. The synthesized crown ethers were characterized respectively by IR, NMR. GC-Mass.

• Archives of Pharmacal Research
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• v.27 no.8
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• pp.811-815
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• 2004

Coumarin and its derivatives occur widely in nature. Many attempts were made for synthesis of various coumarin derivatives because of their interesting biological activities. In this study, solid phase synthetic approach of 3-(4-hydroxyphenyl)coumarin was achieved for combinatorial synthesis of substituted 3-phenylcoumarin analogues. Starting from 4-hydroxyphenylacetic acid methyl ester, release of 3-(4-hydroxypnehyl)coumarin from polymer support was accom-plished.

• Molecules and Cells
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• v.39 no.4
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• pp.310-315
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• 2016

Coumarin is a phenolic compound that mainly affects the liver due to its metabolization into a toxic compound. The deterrent and ovicidal activities of coumarin in insect models such as Drosophila melanogaster have been reported. Here we explore the molecular mechanisms by which these insects protect themselves and their eggs from this toxic plant metabolite. Coumarin was fatal to the flies in a dosage-dependent manner. However, coumarin feeding could be inhibited through activation of the aversive gustatory receptor neurons (GRNs), but not the olfactory receptor neurons. Furthermore, three gustatory receptors, GR33a, GR66a, and GR93a, functioned together in coumarin detection by the proboscis. However, GR33a, but not GR66a and GR93a, was required to avoid coumarin during oviposition, with a choice of the same substrates provided as in binary food choice assay. Taken together, these findings suggest that anti-feeding activity and oviposition to avoid coumarin occur via separate mechanisms.

• Archives of Pharmacal Research
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• v.26 no.9
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• pp.686-696
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• 2003

Ethyl (coumarin-4-oxy)acetate 1 was prepared through the reaction of 4-hydroxycoumarin with ethyl bromoacetate. Compound 1 was allowed to react with hydrazine hydrate to produce coumarin-4-oxyacetic hydrazide 2. The synthesis of N-(arylidene and alkylidene)-coumarin-4-oxyacetic hydrazones 3-20 was performed. The preparation of 2-substituted-3-[(coumarin-4-oxy) acetamido]thiazolidinones 21-26 and 2-[(coumarin-4-oxy )methyl]-4-acetyl-5-substituted-$\Delta^2$-1,3,4-oxadiazolines 27-33 was performed by the reaction of the hydrazones 3, 4, 7, 9, 12, 14 with mercaptoacetic acid and the hydrazones 3, 4, 5, 7, 12, 15, 16 with acetic anhydride, respectively. The antiviral activities, cytotoxicities and structure-activity relationship (SAR) towards different microorganisms of the prepared compounds were studied.

• Archives of Pharmacal Research
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• v.12 no.3
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• pp.181-185
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• 1989

When 3-acetyl coumarin derivatives are treated with bromine, 3-(w-bromoacetyl) coumarin derivatives are obtained. The reaction of 3-(w-bromoacetyl)coumarin derivatives with thiourea or with amines for two hours leads to the formation of 2-Amino-4-(3-coumarinyl) thiazole or 3-(w-aminoacetyl) coumarin derivatives, respectively. While 3-(w-bromoacetyl) coumarin derivatives react with amines for 5-8 hours to yield imino derivatives of 3-(w-aminoacetyl) coumarin. The antimicrobial activity of Ia-b, IIa-c, IVc-f, IVh and V$_{c}$, f, h, k, m, and q was studied.d.

• Journal of Photoscience
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• v.2 no.2
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• pp.95-98
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• 1995

The photodimers with cyclobutane rings and C$_2$ symmetry, derived from coumarin (syn, head to tail and anti, head to head) have been calculated by PM3-UHF-CI and Molecular Mechanics force field. The photocycloaddition to coumarin and 5,7-dimethoxycoumarin(DMC) dimers were deduced to be formed by their preferable frontier orbital interactions and via more stable cycloaddition by the C$_3$, C$_4$ bond. These results are consistent with the coumarin dimer model that the theoretical C$_4$-photocyclodimer of coumarin is predicted much more than the experimental C$_4$-photocyclodimer.

• Journal of the Korean Chemical Society
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• v.42 no.1
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• pp.22-27
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• 1998

Fluorescence quenching of coumarin 153 and coumarin 481 with N,N-dimethylaniline in various solvents was investigated. Quenching rate constants are related to diffusion-limited rate constants to some extent. It is noted that smaller discrepancy was observed between the diffusion-limited rate constant and the experimental quenching rate constant when the stick boundary condition rather than the slip boundary condition was applied for estimating the diffusion coefficients. In nonpolar solvent like cyclohexane fluorescence quenching is adequately explained by the diffusion controlled process within the experimental error, but in acetonitrile the quenching rate constant was estimated to be consistently smaller than the diffusion limited rate constant. This may suggest that fluorescence quenching of coumarin dyes be affected not only by the molecular diffusion but also by the intramoleccular process such as charge separation.

• Journal of the Korean Society of Tobacco Science
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• v.4 no.2
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• pp.63-66
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• 1982

Coumarin was pyrolyzed at $500^{\circ}C$ in a stream of nitrogen. The pyrolyzates of coumarin were adsorbed on the activated charcoal and then eluded by carbon disulfide. The eluted pyrolyzates were identified using a gas chromatography/mass spectrometry. Benzene, toluene, phenylacetylene, styrene, benzofuran and naphthalene were detected from the pyrolyzates of coumarin on the basis of their mass spectra. The pyrolytic mechanism of coumarin was also discussed.

• Journal of the Korean Chemical Society
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• v.58 no.3
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• pp.297-302
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• 2014

The synthetic route to coumarin systems is well established and one approach of particular interest leads to the intermediate 7-diethylamino-3-formylcoumarin. A combination of the N,N-diethylamino-coumarin donor with a wide range of acceptor groups of varying electron withdrawing strength should permit the synthesis of a series of extended coumarin dyes with absorption maxima range from 500 to 600 nm, or even beyond. In this communication, a novel efficient synthesis of indoles, benzothiazole and benzoxazole based on coumarin chromophores were achieved and the coloristic and fluorophoric properties of these chromophores were studied.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.1
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• pp.53-58
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• 2013

The active antifouling compounds coumarin and its derivatives were isolated from the cinnamon tree Cinnamomum loureiroi. The antifouling activities were determined using representative soft fouling organisms: the seaweed Ulvapertusa and diatom Navicula annexa. The chemical constituents with antifouling activities were identified as coumarin, hydroxylcoumarin, coumaric acid, and cinnamaldehyde by interpreting nuclear magnetic resonance, and high-resolution mass spectroscopy data. These compounds were isolated from 1.09 g of crude Cinnamomum sp. methanol extract, yielding approximately 18.4, 6.3, 9.8, and 14.7 mg of coumarin, hydroxylcoumarin, coumaric acid, and cinnamaldehyde, respectively. The compounds inhibited U. pertusa zoospores with $EC_{50}$ values of $0.13-0.25{\mu}g/mL$, and the diatom N. annexa with $EC_{50}$ of $0.21-0.81{\mu}g/mL$.