Chlorobactine A, a Dimeric Dichlorated Metabolite from Marine-Derived Streptomyces thermolineatus NAK03196

Using the one strain many compounds (OSMAC) strategy and guided by LC–MS results, we explored the metabolites of marine algae-derived strain Streptomyces thermolineatus NAK03196 and discovered a new class of molecules with an unexpected skeleton, chlorobactine A (1). Its structure was determined by 1D and 2D NMR spectroscopy, HR-ESI–MS, single-crystal X-ray diffraction analysis (Cu Kα), and ECD calculation. Chlorobactine A (1) contains dichlorine atoms and possesses a unique 6/6/6 tricyclic fused skeleton structure. Meanwhile, a plausible biosynthetic pathway for 1 was proposed based on the molecular structures and bioinformatic analysis.