Planta Med 2016; 82 - PC71
DOI: 10.1055/s-0036-1578773

Cytotoxic Lignan Esters From The Bark And Roots Of Syzygium Cf. Lineatum

Y Ren 1, TN Ninh 2, HB Chai 1, JC Gallucci 3, DD Soejarto 4, 5, AD Kinghorn 1
  • 1Division of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, OH 43210, United States
  • 2Institute of Ecology and Biological Resources, Vietnam Academy of Science and Technology, Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam
  • 3Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, United States
  • 4Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, Chicago, IL 60612, United States
  • 5Science and Education, Field Museum of Natural History, Chicago, IL 60605, United States

In a search for anticancer agents from higher plants, a sample of the dried bark and roots of Syzygium cf. lineatum (Bl.) Merr. & Perry (Myrtaceae) collected in Vietnam showed cytotoxic activity and was selected as a lead. Separation of the methanol extract of this plant sample, using column chromatography guided by the HT-29 human colon cancer cell line, resulted in the isolation and characterization of three new and several known lignan esters and a new triterpene acetate. The structures of the new compounds were elucidated by interpretation of their ECD, IR, UV, NMR, and mass spectra, with those of the known compounds being characterized by comparison of their spectroscopic data with literature values. The conformation and relative configuration of a known lignan, (2S,3S)-2,3-bis[(4-hydroxy-3-methoxyphenyl)methyl]-1,4-butanediol 1,4-diferulate, were confirmed or revised by analysis of the single-crystal X-ray diffraction, with the absolute configuration of all analogues isolated being established by investigation of their specific rotation values and ECD spectra. All compounds isolated in the present study were evaluated for their cytotoxicity against the HT-29 cell line, and several lignan esters were found to be active. A preliminary structure-activity relationship study showed that both the ester groups and the dimeric units are required for these compounds to mediate cytotoxicity against HT-29 cells.