title: ent-pimarane-type diterpenoids from Siegesbeckia orientalis L.
abstract: A new ent-pimarane glucoside, named hythiemoside B (4), was isolated from the aerial part of Siegesbecikia orientalis L. (Asteraceae) together with four known ent-pimarane-type diterpenoids: darutigenol (1), darutoside (2), hythiemoside A (3), and ent-(15R),16,19-trihydroxypimar-8(14)-ene 19-O-beta-D-glucopyranoside (5). The structure of the new compound was elucidated by spectroscopic analyses and chemical transformation. The NMR data of compounds 1 (1H-) and 5 (1H- and 13C-) were also compiled in this study on the basis of 2D experiments.
authors.affiliation: Faculty of Chemistry, College of Natural Science, Vietnam National University, Hanoi, Vietnam.
authors.forename: Phan Minh
authors.initials: PM
authors.lastname: Giang
authors.forename: Phan Tong
authors.initials: PT
authors.lastname: Son
authors.forename: Hideaki
authors.initials: H
authors.lastname: Otsuka
mesh_terms: D045784:Abietanes / Q000737:chemistry* / Q000302:isolation & purification; D019659:Asteraceae / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D004224:Diterpenes / Q000737:chemistry* / Q000302:isolation & purification; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D016339:Spectrometry, Mass, Fast Atom Bombardment; D017550:Spectroscopy, Fourier Transform Infrared; D014744:Vietnam
chemical_list: D045784:Abietanes; D004224:Diterpenes; C500865:hythiemoside B; C433018:pimarane