title: Bioactive constituents of Thuja occidentalis.
abstract: An ethyl acetate-soluble extract of the combined leaves and twigs of Thuja occidentalis was found to inhibit 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced ornithine decarboxylase (ODC) in cultured mouse epidermal ME 308 cells. Bioassay-guided fractionation of this extract led to the isolation of six active constituents (1-6), namely, (+)-7-oxo-13-epi-pimara-14,15-dien-18-oic acid (1), (+)-7-oxo-13-epi-pimara-8,15-dien-18-oic acid (2), (+)-isopimaric acid (3), (1S,2S,3R)-(+)-isopicrodeoxypodophyllotoxin (4), (-)-deoxypodophyllotoxin (5), and (-)-deoxypodorhizone (6). Compounds 1 and 4 are new natural products, and their structures and stereochemistry were determined using spectroscopic methods. Compounds 1-6 were evaluated for inhibition of the transformation of murine epidermal JB6 cells, inhibition of ornithine decarboxylase induction with murine epidermal ME 308 cells, and cytotoxic activity against KB cells.
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, Chicago, Illinois 60612, USA.
authors.forename: L C
authors.initials: LC
authors.lastname: Chang
authors.forename: L L
authors.initials: LL
authors.lastname: Song
authors.forename: E J
authors.initials: EJ
authors.lastname: Park
authors.forename: L
authors.initials: L
authors.lastname: Luyengi
authors.forename: K J
authors.initials: KJ
authors.lastname: Lee
authors.forename: N R
authors.initials: NR
authors.lastname: Farnsworth
authors.forename: J M
authors.initials: JM
authors.lastname: Pezzuto
authors.forename: A D
authors.initials: AD
authors.lastname: Kinghorn
mesh_terms: D000818:Animals; D001685:Biological Factors / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D051379:Mice; D015394:Molecular Structure; D065108:Ornithine Decarboxylase Inhibitors; D014197:Trees / Q000737:chemistry*; D014407:Tumor Cells, Cultured
chemical_list: D001685:Biological Factors; D065108:Ornithine Decarboxylase Inhibitors