• 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.35 no.4 s.139
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• pp.315-319
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• 2004

Three coumarin derivatives, which stimulate collagen biosynthesis in human fibroblasts were isolated from Angelica dahurica root which has been used in traditional medicine for cold, headache, discharging blood and women's diseases. Three coumarin derivatives were identified as 5-benzofuranacrylic acid, $6,7-dihydroxy-4-(3-methyl-2-butenyl)-{\delta}-lactone\;(prangenidin)$, 5-benzofuranacrylic acid, $6,7-dihydroxy-4-methoxy-{\delta}-lactone\;(8-hydroxybergapten)$ and 5-benzofuranacrylic acid, 8-hydroxypsoralen(xanthotoxol) from their spectral data.

• Biomedical Science Letters
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• v.27 no.4
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• pp.270-276
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• 2021

Physiological agents trigger a signaling process called "inside-out signaling" and activated platelets promote adhesion, granule release, and conformational changes of glycoprotein IIb/IIIa (αIIb/β₃). Activated αIIb/β₃ interacts with fibrinogen and initiates a second signaling step called "external signaling". These two signaling pathways can cause hemostasis or thrombosis, and thrombosis is a possible medical problem in arterial and venous vessels, and platelet-mediated thrombosis is a major cause of cardiovascular disease (CVD). Therefore, modulating platelet activity is important for platelet-mediated thrombosis and cardiovascular disease. Esculetin is a coumarin-based physiologically active 6,7-dihydroxy derivative known to have pharmacological activity against obesity, diabetes, renal failure and CVD. Although some studies have confirmed the effects of esculetin in human platelet activation and experimental mouse models, it is not clear how esculetin has antiplatelet and antithrombotic effects. We confirmed the effect and mechanism of action of escultein on human platelets induced by collagen. As a result, esculetin decreased Ca²⁺ recruitment through upregulation of inositol 1, 4, 5-triphosphate receptor. In addition, esculetin upregulates cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP)-dependent pathways and inhibits fibrinogen binding and thrombus contraction. Our results demonstrate the antiplatelet effect and antithrombotic effect of esculetin in human platelets. Therefore, we suggest that esculetin could be a potential phytochemical for the prevention of thrombus-mediated CVD.

• Applied Biological Chemistry
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• v.51 no.2
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• pp.136-141
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• 2008

The chromatographic separation of organic solvent extracts of liverwort led to the isolation of six compounds. 2-Chromenone (1), 3, 4-dihydroxy-cinnamic acid (2), 3, 3', 4', 5, 7-pentahydroxy-2-phenylchromen-4-one (3), kaemperol-3-O-${\beta}$-D-glucopyranoside (4), 3-[[3-(3,4-Dihydroxyphenyl)-1-oxo-2-propenyl]oxy]-1, 4, 5-trihydroxycyclohexane carboxylic acid (5) and quercetin-3-O-rutinoside (6) were isolated from the methanolic extracts of the all part of Climacium dendroides. Their structure were established by chemical and spectroscopic methods. All compounds were isolated for the first time from this plant Climacium dendroides.