Halogenated secondary metabolites from Laurencia obtusa.

A new sesquiterpene (1), and a halogenated C15 acetogenin (2), a stereoisomer of neoisoprelaurefucin were isolated from Laurencia obtusa. Four known compounds laurencienyne (3), rogiolenyne B (4), obtusenol (5), and (3E)-dactomelyne (6) were also isolated from this alga. Rogiolenyne B (4) and (3E)-dactomelyne (6) were found for the first from this species.

Brominated sesquiterpenes from the red alga Laurencia obtusa.

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.

Fatty acid composition of Dracunculus vulgaris Schott (Araceae) seed oil from Turkey.

Dracunculus vulgaris Schott is only one taxon of the genus Dracunculus (Araceae) in Turkey. The tubers and the fruits with the seeds of D. vulgaris have long been in use for the treatment of rheumatism and hemorrhoids, respectively.