title: Structure determination of ramosine, a guaianolide, by NMR spectroscopy.
abstract: Ramosine, a new sesquiterpene lactone, was isolated from the chloroform fraction of Amberboa ramosa and the structure was assigned as 4beta-(hydroxymethyl)-3beta,4alpha-dihydroxy-8alpha-[(S)-3-hydroxy-2-ethylenepropionyloxy]-1alphaH, 5alphaH,6betaH,7alphaH,11betaH,11alpha-methylguaia-10(14)-en-6, 12-olide by extensive NMR studies.
authors.affiliation: International Centre for Chemical Sciences, H.E.J. Research Institute of Chemistry, University of Karachi, Karachi-75270, Pakistan.
authors.forename: Sher Bahadar
authors.initials: SB
authors.lastname: Khan
authors.forename: Nighat
authors.initials: N
authors.lastname: Afza
authors.forename: Abdul
authors.initials: A
authors.lastname: Malik
authors.forename: Azhar
authors.initials: A
authors.lastname: ul Haq
authors.forename: Zaheer
authors.initials: Z
authors.lastname: Ahmed
mesh_terms: D002725:Chloroform / Q000737:chemistry; D007783:Lactones / Q000737:chemistry* / Q000302:isolation & purification; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008968:Molecular Conformation; D010946:Plants, Medicinal / Q000737:chemistry*; D012717:Sesquiterpenes / Q000737:chemistry*
chemical_list: D007783:Lactones; D012717:Sesquiterpenes; C499646:ramosine; D002725:Chloroform