title: Dinoxin B, a withanolide from Datura inoxia leaves with specific cytotoxic activities.
abstract: A new withanolide, dinoxin B (12,21-dihydroxy-1-oxowitha-2,5,24-trienolide-27-O-β-D-glucopyranoside, 1), was isolated from a methanol extract of Datura inoxia leaves, using bioassay-guided fractionation. The structure was determined by spectroscopic techniques, including (1)H, (13)C, and 2D NMR experiments as well as by HRMS. Extracts and the purified compound were tested for their antiproliferative activities toward a panel of human normal and cancer cell lines. Dinoxin B (1) and its aglycone (2) exhibited submicromolar IC(50) values against multiple human cancer cell lines. Among the most sensitive were several breast cancer cell lines. Dinoxin B (1) was found only in D. inoxia and was not detected in D. metel or D. stramonium. The accumulation of this compound was limited largely to leaf tissue, with little to none detected in extracts from the flowers, fruits, roots, or stems of D. inoxia.
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, National Center of Agricultural Utilization Research, Functional Foods Research, 1815 N. University Street, Peoria, Illinois 61604, United States.
authors.forename: Karl
authors.initials: K
authors.lastname: Vermillion
authors.forename: F Omar
authors.initials: FO
authors.lastname: Holguin
authors.forename: Mark A
authors.initials: MA
authors.lastname: Berhow
authors.forename: Richard D
authors.initials: RD
authors.lastname: Richins
authors.forename: Thurman
authors.initials: T
authors.lastname: Redhouse
authors.forename: Mary A
authors.initials: MA
authors.lastname: O'Connell
authors.forename: Jeff
authors.initials: J
authors.lastname: Posakony
authors.forename: Sumit S
authors.initials: SS
authors.lastname: Mahajan
authors.forename: Sean M
authors.initials: SM
authors.lastname: Kelly
authors.forename: Julian A
authors.initials: JA
authors.lastname: Simon
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D032302:Datura / Q000737:chemistry*; D004354:Drug Screening Assays, Antitumor; D005960:Glucosides; D006801:Humans; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D018515:Plant Leaves / Q000737:chemistry; D054358:Withanolides / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D005960:Glucosides; D054358:Withanolides; C557515:dinoxin B