Chemical constituents of the brown alga Dictyopteris divaricata

A novel sesquiterpene-substituted benzoic acid, named dictyvaric acid (1), together with nine known compounds (2-10), have been isolated from the brown alga Dictyopteris divaricata Okam. The structure of 1 was elucidated as 3-(decahydro-2-hydroxy-2,5,5,8a-tetramethyl-1-naphthalenyl)-methyl]-4-hydroxybenzoic acid by spectroscopic methods, including IR, FABMS, HR-FABMS, 1D and 2D NMR techniques. All compounds were obtained from this species for the first time.