Neocomplanines A and B, a Complanine Family Isolated from the Marine Fireworm

Two new members of the complanine family, neocomplanines A (2) and B (3), were isolated as minor components of the methanolic extract of the “marine fireworm” Eurythoe complanata. The structures of the neocomplanines were revealed spectroscopically to be a trimethylammonium unit with a saturated carbon chain. The planar structures of neocomplanines A and B were confirmed successfully through total syntheses that used epichlorohydrin as a starting material. The neocomplanines show inflammatory activity and also enhanced PKC activity in combination with TPA in the presence of Ca2+ in vitro; both are similar to the effects of complanine (1). The molecular mechanism of the effects of complanine-related compounds is discussed.