Anthraquinones, naphthoquinones and naphthohydroquinones from Rubia oncotricha

From the roots of Rubia oncotricha, two new naphthoquinones, three new naphthohydroquinones and a new anthraquinone were isolated together with seven known compounds. The structures of the new substances were established by various chemical and spectroscopic means. The chemotaxonomic significance of these findings also is discussed.