title: Constituents of rosaceous plants. I. Structure of new triterpenoids from Cowania mexicana.
abstract: In our search for possible anti-tumor-promoters, we carried out an investigation of the leaves and branches of Cowania mexicana D. DON (Rosaceae). Two new cucurbitane type triterpenes, 15-oxo-cucurbitacin F (3) and 15-oxo-23,24-dihydrocucurbitacin F (4), were isolated together with cucurbitacin F (1) and 23,24-dihydrocucurbitacin F (2). These triterpenes were inhibitorss of Epstein-Barr virus early antigen activation induced by 12-O-tetradecanoylphorbol-13-acetate, a well-known tumor-promoter. The structures of 3 and 4 were determined from 2D-NMR spectral data and difference NOE experiments.
authors.affiliation: Kyoto Pharmaceutical University, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Konoshima
authors.forename: M
authors.initials: M
authors.lastname: Takasaki
authors.forename: M
authors.initials: M
authors.lastname: Kozuka
authors.forename: M
authors.initials: M
authors.lastname: Haruna
authors.forename: K
authors.initials: K
authors.lastname: Ito
authors.forename: J R
authors.initials: JR
authors.lastname: Estes
authors.forename: K H
authors.initials: KH
authors.lastname: Lee
mesh_terms: D016588:Anticarcinogenic Agents / Q000737:chemistry / Q000494:pharmacology*; D000956:Antigens, Viral / Q000187:drug effects; D004854:Herpesvirus 4, Human / Q000276:immunology; D010946:Plants, Medicinal / Q000737:chemistry*; D014315:Triterpenes / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D016588:Anticarcinogenic Agents; D000956:Antigens, Viral; C033305:Epstein-Barr virus early antigen; D014315:Triterpenes