title: A new flavone C-glycoside and antiplatelet and vasorelaxing flavones from Gentiana arisanensis.
abstract: A new flavone C-glycoside, isovitexin 6"-O-glucoside (1), and three known flavonoids, quercetin, isovitexin, and luteolin-7-O-beta-D-glucoside, have been further isolated from the whole plant of Gentiana arisanensis Hayata. The new compound was characterized by spectral methods and chemical reactions. The antiplatelet effects of isovitexin 6"-O-glucoside (1), isoorientin (2), 2 peracetate (3), isovitexin (4), luteolin 7-O-beta-D-glucoside (5), luteolin (6), isoorientin 6"-O-glucoside (7), and 7 peracetate (8) were studied using washed rabbit platelets. Of the compounds tested, 6 showed potent antiplatelet effects on arachidonic acid (AA)-induced platelet aggregation (IC50 = 43.5 microM). The effect of 2, 5, and 6 on the contraction of rat thoracic aorta was also studied. Compound 6 depressed markedly the contraction induced by Ca2+ (1.9 mM) in high-K+ (80 mM) medium, with an IC50 of about 156 microM and also inhibited noradrenaline (3 microM)-induced phasic and tonic contractions, with an IC50 of about 68 and 72 microM, respectively.
authors.affiliation: School of Pharmacy, Kaohsiung Medical College, Taiwan, Republic of China.
authors.forename: C N
authors.initials: CN
authors.lastname: Lin
authors.forename: S H
authors.initials: SH
authors.lastname: Kuo
authors.forename: M I
authors.initials: MI
authors.lastname: Chung
authors.forename: F N
authors.initials: FN
authors.lastname: Ko
authors.forename: C M
authors.initials: CM
authors.lastname: Teng
mesh_terms: D000818:Animals; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D010944:Plants / Q000737:chemistry*; D010975:Platelet Aggregation Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D011817:Rabbits; D051381:Rats; D017208:Rats, Wistar; D013057:Spectrum Analysis; D014665:Vasodilator Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D005419:Flavonoids; D010975:Platelet Aggregation Inhibitors; D014665:Vasodilator Agents; C108205:isovitexin 6''-O-glucoside