New sphingosines from a gorgonian, Pseudopterogorgia australiensis Ridley, of the Indian Ocean.

Two new sphingosines, (2S,3R)-2-(docosanoyl amino)nonadecane-1,3-diol (1) and (2S,3S,4R)-2-[(2'R)-2'-hydroxynonadecanoylamino]nonadecane-1,3,4-triol (3), along with the known (2S,3R,4E)-2-(heptadecanoylamino)octadec-4-ene-1,3-diol, have been isolated from Pseudopterogorgia australiensis, of the Indian Ocean. The structures were deduced from spectral and chemical methods. Compounds 1-3 showed moderate antibacterial activity.