title: A cytotoxic triketone-phloroglucinol-bullatenone hybrid from Lophomyrtus bullata.
abstract: Cytotoxic activity against the P388 cell line was seen in a crude extract of the New Zealand shrub Lophomyrtus bullata(Myrtaceae). Bioactivity-guided isolation led to a compound with NMR spectra complicated by the presence of two isomers. These crystallised together and an X-ray structure showed them to be stereoisomeric hybrids of triketone, phloroglucinol and bullatenone units. NMR measurements on the mixed isomers, as well as a cyclic ether produced from them by acid catalysed dehydration, were consistent with these structures. The natural products, named bullataketals A and B, have cytotoxic activity against the P388 cell line (IC(50) 1 microg ml(-1)), and antimicrobial activity against Bacillus subtilis.
authors.affiliation: Plant Extracts Research Unit, New Zealand Institute for Crop & Food Research Limited, Department of Chemistry, University of Otago, Dunedin, New Zealand.
authors.forename: Lesley
authors.initials: L
authors.lastname: Larsen
authors.forename: Michael H
authors.initials: MH
authors.lastname: Benn
authors.forename: Masood
authors.initials: M
authors.lastname: Parvez
authors.forename: Nigel B
authors.initials: NB
authors.lastname: Perry
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D002247:Carbon Isotopes; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D018360:Crystallography, X-Ray; D007659:Ketones / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008958:Models, Molecular; D015394:Molecular Structure; D027822:Myrtaceae / Q000737:chemistry*; D010696:Phloroglucinol / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D018515:Plant Leaves / Q000737:chemistry; D011522:Protons; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; D002247:Carbon Isotopes; D007659:Ketones; D011522:Protons; D010696:Phloroglucinol