• Bulletin of the Korean Chemical Society
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• v.22 no.2
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• pp.179-182
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• 2001

Photocyclizable poly(cinnam-4'-yl methyl methacrylate) derivatives bearing methoxy benzene (PMCMMA), anthracene (PACMMA), and coumarin (PCCMMA) have been synthesized via Heck type reaction. Three different types of polymers are photoreactable usin g linearly polarized UV light and applicable as liquid crystal alignment layer. Anthracence and coumarin containing polymers (PACMMA, PCCMMA) have better thermal stability than PMCMMA. This observation may be attributed to the glass transition temperature elevation due to the bulky size and another photocrosslinking site provided by anthracene or coumarin group.

• Korean Chemical Engineering Research
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• v.51 no.1
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• pp.157-161
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• 2013

Low priced and environment-friendly natural dye from coumarin- containing plants for the dye sensitized solar cell (DSSC) was developed. Dyes were extracted from cinnamon and angelica that contained coumarin derivatives, and DSSCs employing these dyes were prepared. PV efficiency of 0.75% was obtained from cinnamon dye, which is comparable to the highest efficiency reported in precedent studies about natural dye DSSC. It was confirmed by UV-visible and FT-IR spectroscopy that coumarin derivatives in the plants acted as photosensitive material.

• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.43-48
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• 2009

The synthesis of coumarin-based natural products and their derivatives is described. In vitro MDR reversal activities of the synthesized compounds were evaluated in P-glycoprotein over-expressing human sarcoma cell line MES-SA/DX5. Some of the coumarin derivatives were found to show potent MDR reversal activity. In particular, pyridyl derivative (15e) exhibited more potency than verapamil.

• 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 Evidence-Based Herbal Medicine
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• v.3 no.1
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• pp.35-41
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• 2010

From the roots of Angelica dahurica Bentham et Hooker (Umbelliferae), three known coumarin derivatives have been isolated and identified as 8-(2-hydroxy-3-methoxy-3-methylbutyloxy) psoralen, 5,8-di(2,3-dihydroxy-3-methylbutyloxy) psoralen, 9-[3-($\beta$-D-glucopyranosyloxy)-2-hydroxy-3-methylbutoxy]-7H-furo[3,2-g][1]benzopyran-7-one. This is the first report of the occurrence of these compounds in this plant. These three compounds were tested for activity in septic shock model. Among these compounds, 2 showed relatively strong preventive activity against septic shock.

• Analytical Science and Technology
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• v.18 no.1
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• pp.89-95
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• 2005

Studies on the electrochemical reduction of 7-acetoxy-4-bromomethyl-coumarin (ABMC), 7-acetoxymethyl coumarin (AMC), and coumarin in 0.1 M tetraethyl ammonium perchlorate acetonitrile solution were carried out with direct current, differential pulse polarography, cyclic voltammetry, and controlled potential coulometry. The electrochemical reduction of ABMC was proceeded through three irreversible steps coupled with the chemical reactions. The solution color was changed to yellow when the carbonyl group was reduced during second step and the color change was independent with bromo group of ABMC. Fluorescent intensity was highest when the electrochemical reduction was controlled at near the overpotential of supporting electrolyte (-2.3 volts).

• Korean Journal of Pharmacognosy
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• v.49 no.3
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• pp.219-224
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• 2018

Artemisia annua L. (Compositae) is an annual herb, which has been traditionally used as an antipyretic and hemostatic agent with the herbal medicine name of Cheong Ho (菁蒿) in Korea and China. In this study, five di-caffeoylquinic acid derivatives and a coumarin were determined from the hot-water extract of aerial parts of A. annua. The structures of isolates were elucidated to be 1,3-di-O-caffeoylqunic acid (1), 3,4-di-O-caffeoylquinic acid (2), 3,5-di-O-caffeoylqiunic acid (3), 1,5-di-O-caffeoylquinic acid (4) and 4,5-di-O-caffeoylquinic acid (5) and scopoletin (6). The presence of 1,5-di-O-caffeoylquinic acid (4) is firstly reported from A. annua in the current study.

• Analytical Science and Technology
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• v.8 no.4
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• pp.655-661
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• 1995

The electrochemical reduction of coumarin derivatives in 0.1M TEAP acetonitrile solution was investigated by the direct current, differential pulse polarography, cyclic voltammetry and controlled potential coulometry. The electrochemical reduction of 7-acetoxy-4-bromomethyl-coumarin(ABMC) was proceeded as an irreversible three steps(-0.58, -1.63 and -2.25 volts) of electrochemical transfer before chemical reaction. The solution color turned to yellow after the carboxyl group was reduced at 2nd step(-1.63 volts vs. Ag-AgCl) and the change in color was independant to the bromo group. Upon the basis of the results on the products analysis and the interpretaton of polarograms, a possible electrochemical reaction mechanism was suggested.

• YAKHAK HOEJI
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• v.13 no.2_3
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• pp.67-70
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• 1969

Gall duct cannulated rats were given daphnetin, umbelliferone, 4-hydroxy-coumarin, dicoumarol, 4,7-dihydroxycoumarin, 4,7-dimethyl-5-hydroxy-coumarin, coumarin-3-carboxylic acid, cinnamic acid, ferulic acid, caffeic acid by duodenal catheter at room temperature and output of bile flow was detected. All of the subjected compounds in this experiment indicated a significant effect on the biliary elimination except cinnamic acid alone. It is suggested that a relationship exists between chemical pattern and biological activity for coumarin derivatives and their precursors, and that the choleretic activity of these compounds requires hydroxylated cinnamic acid structure as the most fundamental chemical pattern.

• 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.