title: Brominated sesquiterpenes from the red alga Laurencia obtusa.
abstract: Four new sesquiterpenes, (8R)-8-bromo-10-epi-beta-snyderol (1), (8S)-8-bromo-beta-snyderol (2), 5-bromo-3-(3'-hydroxy-3'-methylpent-4'-enylidene)-2,4,4-trimethylcyclohexanone (3), and the epoxide 4, have been isolated from the chloroform-methanol extract of Laurencia obtusa, together with the three known compounds alpha-snyderol (5), alpha-snyderol acetate (6), and stigmasterol. The structures of the isolated compounds were elucidated through spectroscopic analyses. Compound 1 showed antimalarial activity, with IC(50) values of 2700 and 4000 ng/mL against the D6 and W2 clones of Plasmodium falciparum, respectively.
authors.affiliation: Faculty of Pharmacy, Istanbul University, 34116, Beyazit-Istanbul, Turkey. gulacti_topcu@hotmail.com
authors.forename: Gulaçti
authors.initials: G
authors.lastname: Topcu
authors.forename: Zeynep
authors.initials: Z
authors.lastname: Aydogmus
authors.forename: Sedat
authors.initials: S
authors.lastname: Imre
authors.forename: Ahmet C
authors.initials: AC
authors.lastname: Gören
authors.forename: John M
authors.initials: JM
authors.lastname: Pezzuto
authors.forename: Jason A
authors.initials: JA
authors.lastname: Clement
authors.forename: David G I
authors.initials: DG
authors.lastname: Kingston
mesh_terms: D000818:Animals; D000962:Antimalarials / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D006842:Hydrocarbons, Brominated / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D020128:Inhibitory Concentration 50; D044722:Laurencia / Q000737:chemistry*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010963:Plasmodium falciparum / Q000187:drug effects*; D012717:Sesquiterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D013237:Stereoisomerism; D013265:Stigmasterol / Q000737:chemistry / Q000302:isolation & purification; D014421:Turkey
chemical_list: D000962:Antimalarials; D006842:Hydrocarbons, Brominated; D012717:Sesquiterpenes; D013265:Stigmasterol