Biosynthetic origins of the isoprene units of gaudichaudianic acid in Piper gaudichaudianum (Piperaceae)

The incorporation of [1-13C]-d-glucose indicates that the biosynthesis of gaudichaudianic acid (1) [(2S)-2-methyl-2-(4′-methyl-3′-pentenyl)-8-(3″-methyl-2-butenyl)-2H-1-benzopyran-6-carboxylic acid], the main metabolite accumulating in Piper gaudichaudianum (Piperaceae), involves both mevalonic acid and the 2-C-methyl-d-erythritol-4-phosphate pathways.