Isolation and Structure of Ciguatoxin-4A, a New Ciguatoxin Precursor, from Cultures of DinoflagellateGambierdiscus toxicusand ParrotfishScarus gibbus

Abstract

A new ciguatoxin congener, ciguatoxin-4A (CTX4A), was isolated from cultures of marine dinoflagellate Gambierdiscus toxicus, and its structure was elucidated to be 52-epiciguatoxin-4B on the basis of spectroscopic data. Chromatographic and spectral comparisons indicated that CTX4A was identical with a structurally unelucidated congener known as scaritoxin or SG1.