The first total synthesis of the azaanthracene kalasinamide (1) is described, and the discrepancy in the reported 13C NMR data and melting points for the natural product from two different sources is resolved. Kalasinamide is prone to autosensitized photooxidation, in solution and in the solid state, to give the corresponding quinone, marcanine A (8). This transformation may be representative of a novel and more general step in the biosynthesis ...
