5H-Furo[3',2':4,5]furo[3,2-b]xanthen-5-one, 3a,12a-dihydro-3a,4,6-trihydroxy-9-(3-hydroxy- 3-methylbutyl)-, (3aR-cis)- 5H-Furo[3',2':4,5]furo[3,2-b]xanthen-5-one, 3a,12a-dihydro-3a,4,6-trihydroxy-9-(3-hydroxy-3-methylbutyl)-, (3aR,12aR)- Austocystin D NSC700893