title: Cytotoxic Triterpenoids from the Barks of Betula platyphylla var. japonica.
abstract: Phytochemical investigation on the barks of Betula platyphylla var. japonica (Betulaceae) was carried out, resulting in the isolation and identification of three new triterpenoids, 27-O-cis-caffeoylcylicodiscic acid (1), 27-O-cis-feruloylcylicodiscic acid (2), and 27-O-cis-caffeoylmyricerol (3), along with six known triterpenoids, obtusilinin (4), winchic acid (5), 27-O-trans-caffeoylcylicodiscic acid (6), uncarinic acid E (7), myriceric acid B (8), and 3-O-trans-caffeoyloleanolic acid (9). The structures of the new compounds were elucidated by extensive spectroscopic methods, including 1D- and 2D-NMR, and HR-ESI-MS. All of the isolated compounds were evaluated for cytotoxicity against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and Bt549). Compounds 2, 6, 8, and 9 exhibited potent cytotoxicity against all of the tumor cells tested (IC50< 10.0 μm), while compounds 3, 4, 5, and 7 showed moderate cytotoxicity against all of the tumor cells tested (IC50< 20.0 μm).
authors.affiliation: School of Pharmacy, Sungkyunkwan University, Suwon, 440-746, Korea.
authors.forename: Hee Jeong
authors.initials: HJ
authors.lastname: Eom
authors.affiliation: School of Pharmacy, Sungkyunkwan University, Suwon, 440-746, Korea.
authors.forename: Hee Rae
authors.initials: HR
authors.lastname: Kang
authors.affiliation: Korea Research Institute of Chemical Technology, Deajeon, 305-600, Korea.
authors.forename: Sang Un
authors.initials: SU
authors.lastname: Choi
authors.affiliation: School of Pharmacy, Sungkyunkwan University, Suwon, 440-746, Korea.
authors.forename: Ki Hyun
authors.initials: KH
authors.lastname: Kim
mesh_terms: D000970:Antineoplastic Agents / Q000302:isolation & purification / Q000494:pharmacology; D029662:Betula / Q000737:chemistry*; D016923:Cell Death / Q000187:drug effects; D045744:Cell Line, Tumor; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D020128:Inhibitory Concentration 50; D015394:Molecular Structure; D064209:Phytochemicals; D024301:Plant Bark / Q000737:chemistry*; D013057:Spectrum Analysis; D014315:Triterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000633:toxicity
chemical_list: D000970:Antineoplastic Agents; D064209:Phytochemicals; D014315:Triterpenes
keywords: 
  Betula platyphylla
  ; Betulaceae; Cytotoxic activities; Triterpenoids