Amphidinolide W, a New 12-Membered Macrolide from Dinoflagellate Amphidinium sp.

Abstract
A new cytotoxic 12-membered macrolide, amphidinolide W (1), has been isolated from a marine dinoflagellate Amphidinium sp., and the structure was elucidated by spectroscopic data including 13C−13C INADEQUATE correlations for its 13C-enriched sample. The absolute stereochemistry of 1 was assigned by combination of J-based configuration analysis and modified Mosher method. Amphidinolide W (1) is the first macrolide without an exomethylene unit among all amphidinolides obtained so far.