Bioactive constituents of Thuja occidentalis.
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.
Chang
L C
LC
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.
Song
L L
LL
Park
E J
EJ
Luyengi
L
L
Lee
K J
KJ
Farnsworth
N R
NR
Pezzuto
J M
JM
Kinghorn
A D
AD
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
D001685:Biological Factors; D065108:Ornithine Decarboxylase Inhibitors