title: Cucurbitane-type triterpenoids from the fruit of Momordica charantia.
abstract: The structures of three new cucurbitane-type triterpenoids isolated from the methanol extract of the fruit of Japanese Momordica charantia were established as (19R,23E)-5beta,19-epoxy-19-methoxycucurbita-6,23,25-trien-3beta-ol (1), (23E)-3beta-hydroxy-7beta-methoxycucurbita-5,23,25-trien-19-al (2), and (23E)-3beta-hydroxy-7beta,25-dimethoxycucurbita-5,23-dien-19-al (3) on the basis of spectroscopic methods. These compounds were accompanied by the known (19R,23E)-5beta,19-epoxy-19,25-dimethoxycucurbita-6,23-dien-3beta-ol (4) and (19R,23E)-5beta,19-epoxy-19-methoxycucurbita-6,23-diene-3beta,25-diol (5). This is the first report of the isolation of tetracyclic triterpenoids possessing a delta23,25-conjugated diene system, viz., 1 and 2, from a natural source.
authors.affiliation: College of Science and Technology, Nihon University, 1-8 Kanda Surugadai, Chiyoda-ku, Tokyo 101-8308, Japan.
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Kimura
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Akihisa
authors.forename: Noriko
authors.initials: N
authors.lastname: Yuasa
authors.forename: Motohiko
authors.initials: M
authors.lastname: Ukiya
authors.forename: Takashi
authors.initials: T
authors.lastname: Suzuki
authors.forename: Masaharu
authors.initials: M
authors.lastname: Toriyama
authors.forename: Shigeyasu
authors.initials: S
authors.lastname: Motohashi
authors.forename: Harukuni
authors.initials: H
authors.lastname: Tokuda
mesh_terms: D005638:Fruit / Q000737:chemistry; D007564:Japan; D015394:Molecular Structure; D029777:Momordica charantia / Q000737:chemistry*; D010946:Plants, Medicinal / Q000737:chemistry*; D013237:Stereoisomerism; D014315:Triterpenes / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: C501793:(19R,23E)-5beta,19-epoxy-19-methoxycucurbita-6,23,25-trien-3beta-ol; C501794:(23E)-3beta-hydroxy-7beta,25-dimethoxycucurbita-5,23-dien-19-al; C501795:(23E)-3beta-hydroxy-7beta-methoxycucurbita-5,23,25-trien-19-al; D014315:Triterpenes