The vinyl-α-substituted cyclopentyl oxylipins.

Hybridalactone, agardhilactone, ecklonialactones, eiseniachlorides, and egregiachlorides, isolated from the marine macroalgae such as Laurencia hybrida, Agardhiella subulate, Ecklonia stolonifera, Eisenia bicyclis, and Egregia menziesii, are biosynthesized through a lipoxygenase (LOX)-mediated oxidative pathway involving polyunsaturated fatty acids (PUFAs). This enzymatic process generates hydroperoxide intermediates, which subsequently undergo regio- and stereospecific transformations to yield structurally diverse oxygenated metabolites, including plasmodiophorols and ectocarpins. These compounds are characterized by a conserved vinylcyclopentyl moiety, a structural hallmark critical to elucidating the mechanistic underpinnings of oxylipin biosynthesis in marine algae. The elucidation of these biosynthetic pathways enhances understanding of oxylipin enzymatic regulation and chemical diversity, while underscoring their ecological roles as signaling or defense molecules in marine ecosystems. Their unique structures and bioactivities offer potential for pharmacological and biotechnological applications, including novel bioactive agents. Investigating their production, structural complexity, and functionality is crucial for advancing marine natural product chemistry and exploring their ecological and industrial significance.