Chlorinated coumarins from the polypore mushroom Fomitopsis officinalis and their activity against Mycobacterium tuberculosis.
Hwang CH, Jaki BU, Klein LL, Lankin DC, McAlpine JB, Napolitano JG, Fryling NA, Franzblau SG, Cho SH, Stamets PE, Wang Y, Pauli GF.
An EtOH extract of the polypore mushroom Fomitopsis officinalis afforded two new naturally occurring chlorinated coumarins, which were identified as the previously synthesized compounds 6-chloro-4-phenyl-2H-chromen-2-one (1) and ethyl 6-chloro-2-oxo-4-phenyl-2H-chromen-3-carboxylate (2). The structures of the two isolates were deduced by ab initio spectroscopic methods and confirmed by chemical synthesis. In addition, an analogue of each was synthesized as 7-chloro-4-phenyl-2H-chromen-2-one (3) and ethyl 7-chloro-2-oxo-4-phenyl-2H-chromen-3-carboxylate (4). All four compounds were characterized physicochemically, and their antimicrobial activity profiles revealed a narrow spectrum of activity with lowest MICs against the Mycobacterium tuberculosis complex.