title: Anti-tumor-promoting rearranged abietane diterpenes from the leaves of Larix kaempferi.
abstract: Two novel rearranged abietane-type diterpene acids, karamatsuic acid (1) and larikaempferic acid (2) were isolated as their corresponding methyl esters, 1a and 2a, from the leaves of Larix kaempferi (Lamb.) Carr. Their structures were established as 9,10 alpha-epoxy-9,10-seco-abieta-8,11,13-trien-18-oic acid and 9 alpha,13 alpha-epoxy-8-oxo-9(8-->7)abeo-7 beta H-abietan-18-oic acid, respectively, by spectral evidence. Compounds 1a, 2a and 12,15-dihydroxydehydroabietic acid (3) exhibited potent inhibitory effects against 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced Epstein-Barr virus early antigen (EBV-EA) activation in Raji cells.
authors.forename: H
authors.initials: H
authors.lastname: Ohtsu
authors.forename: R
authors.initials: R
authors.lastname: Tanaka
authors.forename: S
authors.initials: S
authors.lastname: Matsunaga
authors.forename: H
authors.initials: H
authors.lastname: Tokuda
authors.forename: H
authors.initials: H
authors.lastname: Nishino
mesh_terms: D000818:Animals; D000956:Antigens, Viral / Q000378:metabolism; D000972:Antineoplastic Agents, Phytogenic / Q000737:chemistry / Q000494:pharmacology*; D002273:Carcinogens / Q000037:antagonists & inhibitors*; D002460:Cell Line; D004224:Diterpenes / Q000737:chemistry / Q000494:pharmacology*; D015394:Molecular Structure; D010946:Plants, Medicinal / Q000737:chemistry*; D013755:Tetradecanoylphorbol Acetate / Q000037:antagonists & inhibitors
chemical_list: D000956:Antigens, Viral; D000972:Antineoplastic Agents, Phytogenic; D002273:Carcinogens; D004224:Diterpenes; C033305:Epstein-Barr virus early antigen; C401937:karamatsuic acid; C401936:larikaempferic acid; D013755:Tetradecanoylphorbol Acetate