Draculone, a New Anthraquinone Pigment from the Tropical Lichen Melanotheca cruenta

A new red anthraquinone, draculone, has been isolated from the corticolous tropical lichen Melanotheca cruenta (= Trypethelium cruentum = Pyrenula cruenta) together with minor quantities of the known anthraquinone pigmenthaematommone. The structure of draculone was determined as 2-acetyl-1,3,4,6,8-pentahydroxyanthraquinone by spectroscopic methods.