Zooxanthellatoxin-B, Vasoconstrictive Congener of Zooxanthellatoxin-A from a Symbiotic Dinoflagellate Symbiodinium sp.

Abstract Zooxanthellatoxin-B was isolated from a symbiotic marine alga, Symbiodinium sp. and the structure of zooxanthellatoxin-B was determined to be a 62-membered lactone by comparing spectral data and degradation products with those of zooxanthellatoxin-A.