Colouring Matters of Australian Plants. VIII. Naphthalene Derivatives from Dianella Species

Abstract

The roots of Dianella laevis contain a crystalline glycoside, dianellin, and the corresponding aglycone, dianellidin. Only dianellin has been isolated from D. caerulea. Dianellidin is identified as 1,8-dihydroxy-3-methyl-2-acetonaphthone and the glycoside has the sugars, glucose and rhamnose, attached at the 8-position. Dianellin is readily converted into plumbagin and is a possible natural precursor of this and other naphthoquinones found in plants. There is some evidence for the occurrence of traces of this type of compound in Dianella roots.