title: Glycosylation of ent-kaurene derivatives and an evaluation of their cytotoxic activities.
abstract: OBJECTIVE
  To discover more active and water-soluble derivatives of tetracyclic diterpenoids containing an exo-methylene cyclopentanone or an α-methylenelactone moiety.
  
  
  METHODS
  All of the key intermediates were synthesized from stevioside, and the target compounds were obtained through glycosylation of the 4-carboxyl group. The cytotoxicity of the target compounds against six human cancer cell lines, HepG2, Bel-7402, A549, U251, MCF-7 and MDA-MB-231, were evaluated by the MTT assay.
  
  
  RESULTS
  Compound 1b was more effective than the positive control adriamycin against the HepG2, Bel-7402, A549, MCF-7, and MDA-MB-231 cell lines with IC50 values of 0.12, 0.91, 0.35, 0.08, and 0.07 μmol·L(-1), respectively. Moreover, compound 3c exhibited the most potent and selective cytotoxic activity against the HepG2 cell line (IC50, 0.01 μmol·L(-1)).
  
  
  CONCLUSIONS
  Compounds 1b and 3c could be considered as potential anticancer candidates for further study.
authors.affiliation: Drug Research Institute, China Pharmaceutical University, Nanjing, China.
authors.forename: Min
authors.initials: M
authors.lastname: Zou
authors.forename: Shuang-Shuang
authors.initials: SS
authors.lastname: Yu
authors.forename: Ke
authors.initials: K
authors.lastname: Wang
authors.forename: Da-Yong
authors.initials: DY
authors.lastname: Zhang
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Wu
authors.forename: Wei-Yi
authors.initials: WY
authors.lastname: Hua
mesh_terms: D000970:Antineoplastic Agents / Q000737:chemistry / Q000633:toxicity*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D045786:Diterpenes, Kaurane / Q000737:chemistry / Q000633:toxicity*; D004353:Drug Evaluation, Preclinical; D006031:Glycosylation; D006801:Humans; D015394:Molecular Structure
chemical_list: D000970:Antineoplastic Agents; D045786:Diterpenes, Kaurane; C002627:kaurene