A Reassignment of (−)-Mycothiazole and the Isolation of a Related Diol

Abstract
A reinvestigation of the thiazole constituents from Cacospongia mycofijiensis, collected in Vanuatu, yielded known mycothiazole (3) plus a new derivative, mycothiazole-4,19-diol (6). The E stereochemistry at Δ14,15 of 3 has been revised to Z and the structural features of 6 are elucidated. These compounds, which presumably arise by the action of a polyketide−nonribosomal peptide synthetase (PKS/NRPS) hybrid, possess cytotoxic properties that need further exploration.