RUBROLONE

(2R)-3,4,4a,13aβ-Tetrahydro-3α,4α,4aβ,5-tetrahydroxy-2α,10-dimethyl-8-propyl-2H-pyrano[3'',2'':4',5']furo[3',2':6,7]azuleno[2,1-c]pyridine-7,12-dione