title: Antibacterial triterpenoids from Dillenia papuana and their structure-activity relationships.
abstract: Two new oleanene-type triterpenoids, dillenic acids D and E, have been isolated from the leaves and stems of Dillenia papuana together with the new natural product 3-oxoolean-12-en-30-oic acid. Together with these compounds, the known compound, betulinic acid (3 beta-hydroxy-20(29)-lupen-28-oic acid) was isolated as the major component of the fractions studied. Dillenic acids D and E were characterized as 2,3-seco-2-oxoolean-12-en-3-methylester-30-oic acid and 1 alpha,3 beta-dihydroxyolean-12-en-30-oic acid and their nuclear magnetic resonance data were unambiguously assigned using two-dimensional nuclear magnetic resonance techniques. A comparison of antibacterial activities of these compounds with the earlier reported dillenic acids A-C indicated that, aside from a double bond in gamma- or delta-position to a carboxylic group, a ketone function in ring A of an oleanene-skeleton may be required for the observed activity.
authors.affiliation: Department of Pharmacy, Swiss Federal Institute of Technology (ETH) Zurich, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Nick
authors.forename: A D
authors.initials: AD
authors.lastname: Wright
authors.forename: T
authors.initials: T
authors.lastname: Rali
authors.forename: O
authors.initials: O
authors.lastname: Sticher
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*; D004926:Escherichia coli / Q000187:drug effects* / Q000254:growth & development; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D016982:Micrococcus luteus / Q000187:drug effects* / Q000254:growth & development; D015394:Molecular Structure; D018515:Plant Leaves; D018547:Plant Stems; D010946:Plants, Medicinal; D013329:Structure-Activity Relationship; D014315:Triterpenes / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D014315:Triterpenes