1,8-dihydroxy-3,5,6,7-tetramethoxyxanthone
1,2,3,4,7-pentamethoxyxanthone
1-hydroxy-2,3,4,7-tetramethoxyxanthone
N-mesyl-5,6-dimethoxy-2-(6-methoxy-2-methoxycarbonylanilino)-p-benzoquinone
2,3-dimethoxy-5-(4-methoxy-2-methoxycarbonylphenoxy)benzoquinone