Erythrazoles A–B, Cytotoxic Benzothiazoles from a Marine-Derived <i>Erythrobacter</i> sp.

Abstract

Chemical examination of an extract from an <i>Erythrobacter</i> sp. isolated from mangrove sediments yielded erythrazoles A (<b>1</b>) and B (<b>2</b>). The erythrazoles are of mixed biosynthetic origin containing a tetrasubstituted benzothiazole, an appended diterpene side chain, and a glycine unit. Erythrazole B is cytotoxic to a panel of non-small cell lung cancer (NSCLC) cell lines, with IC₅₀ values of 1.5, 2.5, and 6.8 μM against H1325, H2122, and HCC366, respectively