title: Six new withanolide-type steroids from the leaves of Solanum cilistum.
abstract: Six new withanolide-type steroids, designated cilistols v, t, i, j, y and w (1-6, respectively), were obtained from the leaves of Solanum cilistum. Their respective structures were characterized by spectroscopic means as follows: Cilistol v (1) was (22R,24Z)-1alpha,3beta,22,26-tetrahydroxyergost-5,24-diene 26-O-beta-D-glucopyranoside, which is regarded as the precursor of other withanolide-type steroids included in this title plant. Cilistol t (2) was (22R,24S,25R,26S)-24,25;22,26-diepoxy-1alpha,3beta,26-trihydroxyergost-5-ene 26-O-beta-D-glucopyranoside, and cilistols j (3) and i (4) corresponded to the substances probably formed by the cleavage of the epoxy ring at C-24 and 25 of 2. Cilistol y (5) was 3-O-sulphonyl (22R,24S,25R,26R)-1-oxo-24,25; 22,26-diepoxy-3beta,17alpha,26-trihydroxyergost-5-ene 26-O-beta-D-glucopyranoside, and cilistol w (6) corresponded to the substance obtained by the fission of the epoxy ring at C-24 and 25 of 5. The occurrence of these withanolide type steroids from Solanum genera is rare and worthy of note.
authors.affiliation: Faculty of Pharmaceutical Sciences, Kumamoto University, Japan.
authors.forename: X H
authors.initials: XH
authors.lastname: Zhu
authors.forename: J
authors.initials: J
authors.lastname: Ando
authors.forename: M
authors.initials: M
authors.lastname: Takagi
authors.forename: T
authors.initials: T
authors.lastname: Ikeda
authors.forename: T
authors.initials: T
authors.lastname: Nohara
mesh_terms: D004875:Ergosterol / Q000737:chemistry / Q000302:isolation & purification*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D018515:Plant Leaves / Q000737:chemistry; D019657:Solanaceae / Q000737:chemistry*; D016339:Spectrometry, Mass, Fast Atom Bombardment
chemical_list: D004875:Ergosterol