title: Potential antitumor promoting diterpenoids from the stem bark of Thuja standishii.
abstract: Six diterpenes, including one new natural product, were isolated from a CHCl 3 extract of the stem bark of Thuja standishii. The new compound has been characterized as 15-oxolabda-8(17),13 Z-dien-19-oic acid. The known compounds were identified as ferruginol (2), sugiol (3), isocupressic acid (4), sandaracopimaric acid (5) and 15-oxolabda-8(17),13 E-dien-19-oic acid (6). Compounds 2-5 and the derivatives 4a and 4b were tested for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol 13-acetate (TPA). Compounds 2, 3, 4 and 5 showed strong inhibitory effect on EBV-EA induction (100 % inhibition at 1000 mol ratio/TPA).
authors.forename: Manabu
authors.initials: M
authors.lastname: Iwamoto
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Minami
authors.forename: Harukuni
authors.initials: H
authors.lastname: Tokuda
authors.forename: Hironori
authors.initials: H
authors.lastname: Ohtsu
authors.forename: Reiko
authors.initials: R
authors.lastname: Tanaka
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D004224:Diterpenes / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D018547:Plant Stems / Q000737:chemistry*; D029783:Thuja / Q000737:chemistry*; D014407:Tumor Cells, Cultured
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004224:Diterpenes