Structures of a New Type of Indoloditerpene, Petromindole, and a New Asterriquinone Derivative, PM-53, from the Ascostromata of Petromyces muricatus

A new typw of indoloditerpene, petromindole (1), and a new asterriquinone derivative, PM-53 (2), were isolated from the ascostromata of Petromyces muricatus, along with bisindolylbenzenoids, petromurins A (3)-D (6). The structure of 1 was suggested by spectroscopic data and confirmed by an X-ray crystallographic analysis, while that of 2 was determined by analyses of the various NMR spectra.