... Hydroxydroserone [5] H H CH3 OH OGlc Droserone-5-glucoside [6] OH H CH3 OH OGlc Hydroxydroserone-5-gluside R 6 R7 [7] CH3 H Rossoliside [8] H CH3 2-Methyl-hydrojuglone-4-glucoside ... Drosera [21] Naphthoquinone Droserone Hydroxydroserone Biramentaceonea Droserone-5-glucoside Rossoliside Hydroxydroserone-5-glucoside 2-Methylnaphtazarin-5-O- ... 64 66 68 5.1. 68 5.1.1....