Divinyl ethers and hydroxy fatty acids from three species ofLaminaria (brown algae)

Abstract Three species of brown algae, Laminaria sinclairii, L. saccharina and L. setchellii , have been investigated for the presence of oxylipins. From one, L. sinclairii , three new divinyl ether fatty acids have been characterized as methyl ester derivatives (methyl 12‐[1′ ( Z ),3′( Z )‐hexadienyloxy]‐6( Z ), 9( Z ), 11( E )‐dodecatrienoate, methyl 12‐[1′ ( Z ), 3′ ( Z )‐hexadienyloxy]‐9( Z ), 11( E )‐dodecatrienoate, and methyl 14‐[1′ ( Z ),3′ ( Z )‐hexadienyloxy]‐9( Z ),11( E )‐dodecadienoate, and methyl 14‐[1′ ( Z ),3′( Z )‐hexadienyloxy]‐5( Z ),8( Z ),11( Z ),13( E )‐tetradecatetraenoate) by a variety of spectroscopic methods. In addition, one new [13( S )‐hydroxy‐6( Z ),9( Z ),11( E ),15( Z )‐octadecatetraenoic acid] and four known monohydroxy polyunsaturated fatty acids have been isolated from all three species as their methyl ester derivatives. The occurrence of these compounds in brown algae strongly suggests that these organisms possess an active lipoxygenase(s) with ω6 specificity.