• 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.

• Elastomers and Composites
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• v.44 no.4
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• pp.416-422
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• 2009

4-(6-bromohexyloxy)benzoic acid was synthesized from benzyl 4-Hydroxybenzoate and 1,6-dibromohexane. It was reacted with hydroquinone to obtain a new mesogenic ester having an bromine group. One kind of new photoresponsive coumarin compound was prepared by the reaction of mesogenic ester with coumarin sensitive to the ultraviolet. Structures of the compound were identified by FT-IR and $^1H$-NMR spectroscopies. Their phase transition temperatures and thermal stability were also investigated by differential scanning calorimetry (DSC), polarized optical microscopy (POM) and x-ray diffraction analysis. From optical polarizing microscopy, the prepared compound was found to show enantiotropic liquid crystallinity with smectic and nematic textures.

• Journal of the Korean Chemical Society
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• v.52 no.6
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• pp.649-656
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• 2008

• 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.

• Natural Product Sciences
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• v.4 no.1
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• pp.51-52
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• 1998

From the chloroform extract of the defatted seeds of jute a new coumarin $C_9H_6O_4$, $m.p.\;178-179^{\circ}C$, was isolated. The structure of the compound was established as 4,7-dihydroxy coumarin on the basis of physical methods viz. $^1H\;NMR,\;^{13}C\;NMR$ and Ms.

• Korean Journal of Pharmacognosy
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• v.23 no.1
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• pp.20-23
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• 1992

A new method for the analysis of coumarin constituents in the roots of Peucedanum japonicum by high performance liquid chromatography was established. Among two coumarin constituents identified, peucedanol was confirmed to be applicable to a standard compound. A reversed phase system with a ${\mu}Bondapak$ C_{18}$, column using $H_2O-MeOH=5\;:\;4$ as a moble phase was developed. Peucedanol and a minor constituent, umbelliferone were detected at 333nm and the analysis was successfully carried out within 20 min.

• Elastomers and Composites
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• v.45 no.4
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• pp.286-290
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• 2010

Liquid-crystalline (LC) monomer, which was functionalized with a coumarin group on their extremity, was synthesized by UV light irradiation in their LC phases. LC monomer was converted into the dimers by the cycloaddition reaction of the coumarin group, and the LC phases were maintained after photodimerization reaction. The dimers showed LC phases in the wider temperature range than those of the corresponding monomer. Structures of the compound were identified by FT IR and $^1H$ NMR spectroscopies. Their phase transition temperatures and thermal stability were also investigated by differential scanning calorimetry (DSC), gel permeating chromatography (GPC) and polarized optical microscopy (POM). From optical polarizing microscopy, the prepared polymer shows enantiotropic liquid crystallinity with smectic and nematic textures.

• Korean Journal of Medicinal Crop Science
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• v.7 no.2
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• pp.143-146
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• 1999

The cytotoxicity-guided fractionation of the seed of Plantago asiatica extracts led to the isolation of four compounds, responsible for the cytotoxicity against four human tumor cell lines, i. e., A431 (Human Epidermoid carcinoma), KHOS-NP (Human Osteosarcoma). SNU-1 (Human stomach carcinoma), SNU-C4 (Human large intestine carcinoma). The structure were elucidated by the phsyco chemical data: ${\beta}-sitosterol(C1)$, $cholest-5-en-3{\beta}-ol(C2)$, rutin(C3), $coumarin-7-O-{\beta}-glucopyranoside(C4)$. $IC_{50}$ values of compound C2 were 14.6, 13.5, 10.3, 17.8 ${\mu}g/ml$, and compound C3 and C4 showed activity, having $IC_{50}$ values ranging from 10.3 to 20.14 ${\mu}g/ml$.

• Archives of Pharmacal Research
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• v.27 no.12
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• pp.1207-1210
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• 2004

The antidiabetic activity-guided fractionation and isolation of the 80% EtOH extracts from Peucedani Radix (Peucedanum japonicum, Umbelliferae) led to the isolation and characterization of a coumarin and a cyclitol as active principles, that is, peucedanol 7-O-${\beta}$ -D-glucopyranoside (1) and myo-inositol (2). Their structures were identified by spectroscopic methods. Compound 1 showed 39% inhibition of postprandial hyperglycemia at 5.8 mg/kg dose, and compound 2 also significantly inhibited postprandial hyperglycemia by 34% (P<0.05).

• Korean Journal of Pharmacognosy
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• v.3 no.4
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• pp.215-216
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• 1972

Five compounds$(I{\sim}V)$ were isolated from the roots of Peucedanum terebinthacem growing in Korea. Compounds I, IV and V are ${\beta}-sitosterol$, bergapten and umbelliferone, respectively. IR and NMR spectra of compounds II (mp. $190^{\circ}$) and III(mp. $111{\sim}120^{\circ}$), both white needle crystalls, indicate that compounds II is a furocoumarin and that compound III, yielding decursinol upon saponification, is a pyranocoumarin.