title: Cytotoxic constituents of the roots of Ekmanianthe longiflora.
abstract: Bioactivity-directed fractionation of the CHCl(3) extract of the roots of Ekmanianthe longiflora resulted in the isolation of three new natural products, (2R,3R,4R)-3,4-dihydro-3, 4-dihydroxy-2-(3-methyl-2-butenyl)-1(2H)-naphthalenone (1), (2S,3R, 4R)-3,4-dihydro-3, 4-dihydroxy-2-(3-methyl-2-butenyl)-1(2H)-naphthalenone (2), and (2R, 3aR,9R,9aR)-9-hydroxy-2-(1-hydroxy-1-methylethyl)-2,3,3a,4,9 , 9a-hexahydro-naphtho[2,3-b]furan-4-one (3), together with the known compounds 2-(1-hydroxyethyl)naphtho[2,3-b]furan-4,9-quinone (4), 2-acetylnaphtho[2,3-b]furan-4,9-quinone (5), dehydro-iso-alpha-lapachone (6), alpha-lapachone (7), catalponol, and epi-catalponol. The structures of 1-3 were determined using a combination of NMR spectroscopic techniques, and the absolute configurations of compounds 1 and 2 were obtained using Mosher ester methodology. Compounds 4-6 showed significant cytotoxicity in a panel of human cancer cells. alpha-Lapachone (7) exhibited only marginal activity, and catalponol and epi-catalponol were inactive in this regard. When tested at 72 mg/kg/injection in an in vivo mouse P-388 leukemia system, compound 4 was inactive (110% T/C).
authors.affiliation: Program for Collaborative Research in the Pharmaceutical Sciences and Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, 60612, USA.
authors.forename: S R
authors.initials: SR
authors.lastname: Peraza-Sánchez
authors.forename: D
authors.initials: D
authors.lastname: Chávez
authors.forename: H B
authors.initials: HB
authors.lastname: Chai
authors.forename: Y G
authors.initials: YG
authors.lastname: Shin
authors.forename: R
authors.initials: R
authors.lastname: García
authors.forename: M
authors.initials: M
authors.lastname: Mejía
authors.forename: C R
authors.initials: CR
authors.lastname: Fairchild
authors.forename: K E
authors.initials: KE
authors.lastname: Lane
authors.forename: A T
authors.initials: AT
authors.lastname: Menendez
authors.forename: N R
authors.initials: NR
authors.lastname: Farnsworth
authors.forename: G A
authors.initials: GA
authors.lastname: Cordell
authors.forename: J M
authors.initials: JM
authors.lastname: Pezzuto
authors.forename: A D
authors.initials: AD
authors.lastname: Kinghorn
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000302:isolation & purification* / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D005663:Furans / Q000302:isolation & purification* / Q000494:pharmacology; D006801:Humans; D007941:Leukemia P388 / Q000188:drug therapy; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D051379:Mice; D009284:Naphthols / Q000302:isolation & purification* / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D014407:Tumor Cells, Cultured
chemical_list: C409609:3,4-dihydro-3,4-dihydroxy-2-(3-methyl-2-butenyl)-1(2H)-naphthalenone; C409608:9-hydroxy-2-(1-hydroxy-1-methylethyl)-2,3,3a,4,9,9a-hexahydronaphtho(2,3-b)furan-4-one; D000972:Antineoplastic Agents, Phytogenic; D005663:Furans; D009284:Naphthols