• Macromolecular Research
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• v.12 no.6
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• pp.615-617
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• 2004

We have developed an efficient method for the generation of patterned fluorescence images using a protected precursor molecule. The t-Boc-protecting group of a coumarin derivative was readily removed from a polymer film upon irradiation with UV light in the presence of a photoacid generator to provide the original properties of the coumarin. Fine fluorescence patterns were obtained when using this photolithographic method.

• Korean Journal of Pharmacognosy
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• v.12 no.3
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• pp.143-145
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• 1981

The methanol extract of the rootbark of Fraxinus sieboldiana Blume(Oleaceae) gave two coumarin glycosides, fraxin (fraxetin-8-glucoside), $C_{16}H_{18}O_{10},\;mp\;204^{\circ}\;and\;esculin\;(esculetin-6-glucoside),\;C_{15}H_{16}O_{9},\;mp\;204{\sim}205^{\circ}$. Beside, the methanol extract of the root bark was found to contain mannitol. ${\beta}-sitosterol$ is confirmed by massspectrometry.

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.774-779
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• 1988

The essential oil of Artemiisa lavandulaefolia DC was analyzed by gas chromatography/mass spectrometry (GC/MS). The oil was stored at different conditions for 6 weeks and the changes of color and chemical composition during storage were checked by GC/MS. The experimental results were as follows; (1) More than 186 chemicals were detected by GC. Major components were 1,8-cineol, thujone, camphor, borneol, coumarin, 2,3-dihydrobenzofuran and ${\beta}-biasbolene$. In this study, 3,3,6-trimethyl norpinanol, ${\beta}-farnesene,\;{\alpha}-curmene$ and 7-methoxy coumarin were detected as new compounds in Artemisia species. (2) It was proved that temperature and/ or light had and important effect on the changes of color and volatile components of the essential oil. The relative amounts of limonene and 1.8-cineol were decreasad, on the other hand, ${\beta}-phellandrene\;and\;{\alpha}-terpineol$ were increased during storage.

• Textile Coloration and Finishing
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• v.22 no.2
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• pp.83-87
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• 2010

Crystal structure of coumarin 6 has been solved by X-ray diffraction. The crystals are triclinic, space group P-1, with a=8.823(2) ${\AA}$, b=8.898(2) ${\AA}$, c=11.025(9) ${\AA}$, ${\alpha}$=86.41(3)$^{\circ}$, ${\beta}$=85.39(3)$^{\circ}$, ${\gamma}$=76.23(3)$^{\circ}$, Mr=350.42, V=837.1(3) ${\AA}^3$, Z=2 and R=0.0516. The molecules are packed parallel to each other by weaker ${\pi}{\cdots}{\pi}$ and C-H${\cdots}{\pi}$ interactions. The detailed geometry of C-H${\cdots}{\pi}$ interactions were discussed. The hydrogen bonds and non-traditional C-H${\cdots}O$ interactions join the no-parallel molecules together. All the molecules packed wall-like with the molecular brick.

• 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.

• Natural Product Sciences
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• v.27 no.2
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• pp.128-133
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• 2021

The Coumarin (1,2-benzopyrone) is the main secondary metabolite of Mikania laevigata Sch. Beep ex Baker and Mikania glomerata Spreng., which are popularly known as guaco. These plants have been used mainly in traditional medicine in the treatment of respiratory diseases because their bronchodilator effect. However, there are around 200 species of Mikania, which are quite similar in appearance. From these, only M. leavigata and M. glomerata have high concentrations of coumarins. In this line, the falsification of products Mikania based has been frequent. In this sense, this work demonstrated the application of the easy, fast, e not destructive method based in Nuclear Magnetic Resonance in quantitative mode (qNMR) for the determination of coumarin in both commercial and homemade guaco products. Thus, in the first step the compounds were extract from guaco leaves and syrups using chloroform (CHCl₃), with or without ultrasound. About the method, was linear with a R² = 0.9947 for 1,2-benzopyrone, with detection and quantification limits with were 0.11 and 0.36 mg mL^-1 respectively. In the same line, the method was safe with RSD <0.3% and with recovery ranging from 93-101%. To confirm the applicability of the method, in the last step was applied to 10 real samples (6 from leaves and 4 from syrups). The content of the coumarin in the leaf extract ranged from 0.62 to 1.30 mg mL^-1. For syrups I, II and IV, the content of coumarin was in accordance with the manufacturers. However, for de Syrup III, the concentration was 155% higher. In summary, the qNMR is a rapid method with minimal sample preparation that can be used to quantify coumarin in home-made plant extracts as well as in commercial samples as syrup for instance. This method is applicable for quality control of different plants-based products.

• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.261-264
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• 2000

Organic light emitting diodes(OLEDs) have been expected to find an application as a new type of display since C. W. Tang and VanSlyke first reported on high performance OLEDs. This paper has been stuied a green organic EL device using dye doped emitting layer such as C6(Coumarin 6). In the Alq-based e]ectroluminescence diodes, we applied highly fluorescent molecular(Coumarin 6) and obtained enhancement in the electroluminescence efficiency.

• Archives of Pharmacal Research
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• v.21 no.6
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• pp.723-728
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• 1998

The chemical behaviours of 4-methyl-2-oxo-2H-benzopyran-7-yl oxoacetyl hydrazine (2) towards some different reagents such as anhydride compounds, aromatic aldehydes, carb on disulphide, and nitrous acid yielded the corresponding pathalazine derivatives (3, 4, 5), hydrazone derivative (6), 1,3,4-oxadiazole derivative (7, 8, 9) and acid azide (10) respectively. Treatmen of 10 with absolute alcohols, amines and ethyl amino acid ester gave the corresponding carbamate derivative (11), substituted urea derivative (12) and ethyl substituted alkyl acetate (13) respectively. The biological activity of some synthesized compounds was evaluated.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.821-832
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• 1997

The aim of this study was to separate or purify some bioactive compounds from flowers of alfalfa(Medicago sativa L.) and to test of the isolated compounds on alfalfa for their autotoxicity and on Echinochloa crus-galli for their allelopathy for seed germination and seedling weight. Using thin layer chromatography(TLC) of $CHCl_3$ extracts, the most inhibitory band to alfalfa seed germination was determined. Germination inhibition of this extract suggested a complex chemical interaction. Separation and purification of compounds with CHCl$_3$ extract of fresh alfalfa flowers were conducted by a silica gel TLC, and microcrystalline cellulose TLC(MCTLC), followed by droplet countercurrent chromatography(DCCC) bioassay. Preliminary identification was done by high perfomance liquid chromatography(HPLC) on the most inhibitory fractions in DCCC. Ferulic acid, caffeic acid, vanillic acid, rutin, narringin were identified in fraction 5 and ferulic acid, caffeic acid, vanillic acid, rutin, coumarin in fraction 6. The phytotoxicity of their individual compound was tested on alfalfa and Echinochloa crus-galli seed germination and seedling weight. Coumarin and ferulic acid showed the most inhibitory effect on alfalfa seed germination and Echinochloa crus-galli seedling fresh and dry weight. These compounds may be, at least in part, involved in autotoxicity and allelopathy.

• Korean Journal of Pharmacognosy
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• v.7 no.3
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• pp.195-198
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• 1976

Esculin, esculetin-6-glucoside, m.p. $206^{\circ}C$ was isolated from the fresh bark ok Fraxinus chiisanensis $N_{AKAI}$, one of the indigenous plant of the oleaceous family in Korea, in yield 0.09%.