• Archives of Pharmacal Research
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• v.18 no.4
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• pp.277-281
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• 1995

An anticoagulant, 4-hydroxy-3-[1, 2, 3, 4-tetrahydro-3-[4-(4-trifluoromethylbenzyloxy)phenyll-1 -naphthyl]coumarin (Flocoumafen) was synthesized in 8 steps starting from phenylacetyl shloride and anisole. The key step in the synthesis involves the reaction of 3-(4-methoxyphenyl)-1-teralol with 4-hydroxycoumarin to give 4-hydroxy-3 [1, 2, 3, 4-tetrahydro-3-[4-emthoxyphenyl]-1-naphthyl]coumarin.

• Natural Product Sciences
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• v.15 no.3
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• pp.121-124
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• 2009

Phytochemical investigation of the aerial parts of Lonicera etrusca resulted in the isolation of three iridoids including two aglycones, loganin aglycone (log-1) (1) and lonicerin (log-2) (2), and the known common glycoside loganin (4). The study also afforded a coumarin derivative, 7-hydroxycoumarin (3), and a flavonoid glycoside, luteolin-7-O-$\beta$-D-glucoside (5). The structures were determined utilizing physical, chemical and spectral methods.

• Archives of Pharmacal Research
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• v.9 no.2
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• pp.115-117
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• 1986

Some coumarins were sythesized for the screening of their cytotoxic activities against L1210 cell. Of the conmarins sythesized, 6, 7-dihydroxycoumarin (esculetin) and 7, 8-dihydroxycoumain (dephnetin) as coumarins with dioxygenated A-ring, and 6-acetoxy-5, 7-dimethoxycoumarin and5, 7-dimethoxy-6-hydroxycoumarin as trioxygenated ones, show considerable cytotoxic activities, ED 50 being 4. 3, 8. 8, 17.2 and 5.5 $\mu$g/ml in the same other as the substances. THe extent oxygenation of the A-ring and the positions of the oxygen functions eventually play an important role for the cytotoxic activity.

• Journal of Crop Science and Biotechnology
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• v.11 no.3
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• pp.187-192
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• 2008

The effects of some coumarins(coumarin, 7-hydroxycoumarin, scopoletin and esculetin) were investigated on pumpkin(Cucurbita maxima Duch.) seedlings and on pumpkin glutathione S-transferases(GSTs). Coumarin and esculetin suppressed the growth of seedlings, especially the elongation of roots as well as hypocotyls. Among the compounds tested, only esculetin inhibited the activity of a particular pumpkin GST by 50%, CmGSTU3 toward 1-chloro-2, 4- dinitrobenzene(CDNB) and at a concentration of 22 ${\mu}M$. Both ethylacetae(EtOAc) and water fractions in pumpkin seedlings and different organs of one-month-old pumpkin plants contained esculetin or similar hydrophobic fluorescent substances as well as hydrophilic substances, which showed different degrees of inhibitory effects on CmGSTU3 activity.

• Journal of Photoscience
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• v.2 no.1
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• pp.13-18
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• 1995

The steady-state emission spectra of dicoumarol (DC) in ethanol and EPA have been examined at various temperatures (77-298 K). At room temperature, a fluorescence spectrum of DC in ethanol shows a emission maximum at 350 nm. In EPA a Stokes-shifted emission band appears around 470 nm in addition to the 350 nm emission, and its intensity is enhanced as temperature decreases. This emission is attributed to a zwitterionic tautomer of DC formed by a single excited-state intramolecular proton transfer (ESIPT) along the internal hydrogen-bonding. The fluorescence lifetimes have been measured at 350 and 450 nm as a function of temperature. The fluorescence decay at 350 nm is single exponential at any temperature, whereas the one at 450 nm becomes biexponential at temperatures below 250 K. These results are discussed in terms of a conformational change followed by the ESIPT. The activation energy barrier for the conformational change has been determined to be 3.7 $\pm$ 0.2 kJ/mole.

• YAKHAK HOEJI
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• v.42 no.4
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• pp.422-430
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• 1998

In order to study the effects of Rhei rhizoma, Ephedrae herba and Scutellariae radix on hepatic metabolism, we examined the pretreatment effect of those on the metabolism of 7-e thoxycoumarin (EC). Water extracts (1g/kg) of Rhei rhizoma, Ephedrae herba and Scutellariae radix were administered orally to rats for 7 days, respectively. Livers were then isolated and perfused with 100mcM EC for 2 hours. The metabolites of EC, 7-hydroxycoumarin, sulfate conjugate and glucuronide conjugate were measured in the perfusates. The amount of glucuronide conjugates was decreased in Rhei rhizoma pretreated rats (p<0.01), however, 7-hydroxycoumarin was increased in Ephedrae herba pretreated rats (p<0.01). We examined whether the change of enzyme activity is related to the change of cytochrome P4501A1 and P4502B1 mRNA level in the perfused rat liver, which are responsible for EC metabolism. CYP1A1 and CYP2B1 mRNA level was increased, which was was not statistically significant with rhei rhizoma nor ephedrae herba pretreatment. We also assessed the hepatotoxicity of Rhei rhizoma, Ephedrae herba and Scutellariae radix. The activities of ALT and AST were assayed at 24 hours after 7 days administration. Only the ratio of ALT over AST was increased in ephedrae herba pretreated rats (p<0.05). Lipid peroxidation was increased in Rhei rhizoma treatment (p<0.05), while histopathological examination performed after liver perfusion did not show any difference compared with vehicle treatment. These results suggest that Ephedrae herba pretreatment increases the o-deethy-lation of 7-ethoxycoumarin in rats, which may be mediated by CYP1A1 mRNA induction.

• Nutrition Research and Practice
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• v.9 no.4
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• pp.364-369
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• 2015

BACKGROUND/OBJECTIVES: Inflammation is associated with various types of acute and chronic alcohol liver diseases. In this study, we examined whether umbelliferone (7-hydroxycoumarin, UF) ameliorates chronic alcohol-induced liver damage by modulating inflammatory response and the antioxidant system. METHODS: Rats were fed a Liber-Decarli liquid diet containing 5% alcohol with or without UF (0.05 g/L) for 8 weeks, while normal rats received an isocaloric carbohydrate liquid diet. RESULTS: Chronic alcohol intake significantly increased serum tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and interleukin 6 levels and decreased interleukin 10 level; however, UF supplementation reversed the cytokines related to liver damage. UF significantly suppressed hepatic lipopolysaccharide binding protein, toll-like receptor 4 (TLR4), nuclear factor kappa B, and TNF-${\alpha}$ gene expression increases in response to chronic alcohol intake. Masson's trichrome staining revealed that UF improved mild hepatic fibrosis caused by alcohol, and UF also significantly increased the mRNA expressions and activities of superoxide dismutase and catalase in liver, and thus, decreased lipid peroxide and mitochondrial hydrogen peroxide levels. CONCLUSIONS: The findings of this study indicate that UF protects against alcohol-induced liver damage by inhibiting the TLR4 signaling pathway and activating the antioxidant system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.2
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• pp.173-181
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• 2015

This study investigated the effects of scopoletin (6-methoxy-7-hydroxycoumarin) supplementation on insulin resistance and the antioxidant defense system in chronic alcohol-fed rats. Rats were fed a Lieber-Decarli liquid diet containing 5% ethanol with or without two doses of scopoletin (0.01 and 0.05 g/L) for 8 weeks. Pair-fed rats received an isocaloric carbohydrate liquid diet. Chronic alcohol did not affect fasting serum glucose levels, although it induced glucose intolerance and hyperinsulinemia compared with the pair-fed group and led to insulin resistance. Both doses of scopoletin similarly improved glucose intolerance, serum insulin level, and insulin resistance. Scopoletin supplementation significantly activated phosphatidyl inositol 3-kinase, which was inhibited by chronic alcohol. Two doses of scopoletin up-regulated hepatic mRNA expression and activity of glucokinase as well as down-regulated mRNA expression and activity of glucose-6-phosphatase compared with the alcohol control group. Both doses of scopoletin significantly reduced cytochrome P450 2E1 activity and elevated aldehyde dehydrogenase 2 activity, resulting in a lower serum acetaldehyde level compared with the alcohol control group. Chronic alcohol suppressed hepatic mRNA expression and activities of antioxidant enzymes such as superoxide dismutase, catalase, and glutathione peroxidase; however, they were reversed by scopoletin supplementation, which reduced hydrogen peroxide and lipid peroxide levels in the liver. These results indicate that dietary scopoletin attenuated chronic alcohol-induced insulin resistance and activated the antioxidant defense system through regulation of hepatic gene expression in glucose and antioxidant metabolism.