• YAKHAK HOEJI
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• v.55 no.6
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• pp.473-477
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• 2011

Alzheimer's disease (AD), one of the most common forms of dementia, is a progressive neurodegenerative disorder symptomatically characterized by the decline in memory and cognitive abilities. To date, the successful therapeutic strategy to treat AD is to maintain the levels of acetylcholine (ACh) by inhibiting acetylcholinesterase (AChE) to lead five drugs in clinical use. In this study, several coumarin derivatives were designed based on the lead structure of scopoletin and evaluated for their AChE inhibitory activities.

• Korean Journal of Medicinal Crop Science
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• v.20 no.5
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• pp.315-319
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• 2012

This study was conducted to select plant growth regulators effective at ginseng berry set inhibition to help root growth in Korean ginseng (Panax ginseng C. A. Meyer). PGRs (ethephon, gibberellic acid, maleic hydrazide, coumarin) were applied to field grown 5-year-old Korean ginseng between one and two times, before and during bloom in 2009, 2010. The number of treatment was more effective in ginseng berry set inhibition when used two times compared with one time in GA 1,000 ppm, MH (5,000, 10,000 ppm), coumarin (5,000, 10,000 ppm) treatment. According to treatment period of plant growth regulator, ginseng berry set inhibition rate from 20days before flowering date to 5days after blooming was the highest in MH 5000 ppm showing 99.9% and the lowest in GA 100 ppm showing 32.8%. The spray treatments of Ethephon (50, 150 ppm) and MH (5,000, 10,000 ppm) from 20 days before the flowering bloom up to 5 days before, and coumarin (5,000, 10,000 ppm) from 20 days to 6 days and before blooming that induced the inhibitory effect more than 90% after 12 weeks. Considering ginseng berry set inhibition characteristics and treatment period ethephon and coumarin was important about applied period but, MH treatment appeared to effective ginseng berry set inhibition regardless of treatment period.

• Natural Product Sciences
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• v.11 no.3
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• pp.150-154
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• 2005

The radical scavenging effect of the MeOH extract of Fraxini Cortex on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical was examined. The $CH_2Cl_2$-and n-BuOH-soluble fractions of MeOH extract showed the promising DPPH radical scavenging effects, and further purified by silica gel, Sephadex LH-20 column chromatography, and reversed-phase C-18 MPLC to yield five coumarins, esculetin (1), fraxidin (2), fraxetin (3), fraxidin $8-O-{\beta}-D-glucopyranoside$ (fraxin methyl ether) (5), esculin (6), and a secoiridoid oleuropein (4), and a coumarin-secoiridoid escuside (7). Compounds 1, 3, and 4 showed potent DPPH radical scavenging effects, exhibiting $IC_{50}$ values of 14.68, 9.64, and $22.03\;{\mu}M$, respectively. Compounds 6 and 7 also showed moderate effects with $IC_{50}$ values of 147.79 and $72.73\;{\mu}M$, respectively. L-Ascorbic acid was used as a positive control and exhibited the $IC_{50}$ value of $50.31\;{\mu}M$.

• Journal of the Korean Applied Science and Technology
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• v.29 no.4
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• pp.610-617
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• 2012

Trifoliate orange components consist of several kinds, such as monoterpenes, limonoids, flavonoids, and coumarins. Coumarin derivatives were shown to possess valuable pharmacological properties such as anti-inflammatory and dietary effect. Among them, 7-geranyloxycoumarin 6 is a promising chemopreventive agent againist skin, tongue, oesophaqus and colon carcinogenesis in rodents. Seven new coumarin derivatives structurally related to 7-geranyloxycoumarin were synthesised in good yields by $Cs_2CO_3$/acetonitrile condition. We investigated the effect of anti-inflammatory activity on interleukin-6 for synthesised geranyloxycoumarin derivatives. 6-Geranyoxycoumarin 9 (68.9% / $1{\mu}M$ ; 72.6% / $10{\mu}M$) of the anti-inflammatory activity is far higher than 7-Geranyloxycoumarin 5 (40.1% / $1{\mu}M$ ; 61.1% / $10{\mu}M$) and their other derivatives.

• 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 ${\mu}g/ml$.

• Biomedical Science Letters
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• v.18 no.4
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• pp.438-444
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• 2012

N-acylethanolamines (NAEs) including endocannabinoids, anadamide, are long chain fatty acid ethanolamines and express ubiquitously in animal and plant tissues. NAEs have several pharmacological effects including anti-inflammatory, analgesic and anorexic effects. The levels of NAEs in tissues are strictly regulated by synthesizing and hydrolyzing enzymes because NAEs are not stored in the cell but rather made on demand. NAEs are hydrolyzed to free fatty acids and ethanolamines by fatty acid amide hydrolase and N-acylethanolamine-hydrolyzing acid amidase (NAAA). Here, we suggest the fluorescence-based assay system for NAAA. We developed N-(4-methy-2-oxo-2H-chromen-7-yl)palmitamide (PAAC) as a fluorogenic substrate for NAAA and we also generated NAAA stably expressing COSM6 cell line. When extracts of cells expressing NAAA were incubated with PAAC, NAAA specifically hydrolyzed PAAC to palmitic acids and fluorogenic dye, coumarin. Release of coumarin was monitored by using fluorometer. NAAA hydrolyzed PAAC with an apparent Km of $20.05{\mu}M$ and Vmax of 32.18 pmol/mg protein/min. This assay system can be used to develop inhibitors or activators of NAAA.

• Natural Product Sciences
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• v.6 no.1
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• pp.16-19
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• 2000

Four compounds were isolated from the dichloromethane fraction of Cinnamomi Cortex through bioassay-guided isolation. Their structures were identified as coumarin (1), 3,3-dimethoxy-1-propenyl benzene (2), cinnamic acid (3) and o-methoxy cinnamaldehyde (4) on the basis of spectroscopic data. All four compounds showed inhibitory activities in vitro against monoamine oxidase (MAO) prepared by mouse brain. The $IC_{50}$ values were $41.4\;{\mu}M\;(1),\;110.6\;{\mu}M\;(2),\;252.5\;{\mu}M\;(3)\;and\;83.1\;{\mu}M$ (4), respectively.

• Analytical Science and Technology
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• v.5 no.1
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• pp.83-90
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• 1992

The $^{14}C$-warfarin used as rodenticids was identified from various organs of sprague dawley with scintillation counter. And the cytochrome p-450 which was induced by coumarin derivatives was identified with electrophoresis. The distributions of $^{14}C$-warfarin after $14.8{\mu}Ci/kg$ oral application at each organ was as follows; urine-7.5%, blood-0.44%, feces-0.9%, liver-0.66%, lung-0.86%, kidney-0.8%, heart-0.43% and spreen-0.33% after 24hrs. The cytochrome p-450 was purified by Octyl Sepharose CL-4B hydrophobic chromatography and isozymes were 50.8 Kd in control group, 53.3 Kd and 55.2 Kd in coumarin pretreated group and 50.8 Kd, 54.6 Kd and 57.7 Kd in warfarin pretreated group.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.39 no.2
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• pp.11-16
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• 2002

In this paper, single-layer white organic light emitting device was fabricated on ITO glass substrate using PVK as host, Bu-PBD as electron transport layer, Nile Red, Coumarin 6, TPB as red, green, blue color fluorescent dyes. The red, green, blue organic light emitting devices were fabricated respectively. After the characteristic analysis of each color device, the white organic light emitting device was fabricated with optimized condition of each color device by spin coating method. we obtained white emission CIE coordination of (0.32, 0.34) and luminescence of 785cd/$m^2$ at driving voltage of 20V with condition of PVK(70wt%), Bu-PBD(30wt%), Nile Red(0.015mol%), Coumarin 6(0.04mol%), TPB(3mol%). 

• Journal of the Korean Chemical Society
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• v.54 no.6
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• pp.701-706
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• 2010

Two polyacetylenes (1 and 2), four coumarins (3-6), and one sesquiterpene (7) were isolated from the halophyte Glehnia littoralis. Particularly, compound 6 and 7 were isolated for the first time from Glehnia littoralis. Their chemical structures have been determined by extensive 2-D NMR experiments such as $^1H$, COSY, HMQC and HMBC and by comparison with the reported data in the literature.