A new phenylethanoid triglycoside in Veronica beccabunga L

Besides the expected iridoid glucosides aucubin and catalpol as well as three known esters of the latter, Veronica beccabunga (brooklime) was shown to contain five carboxylated iridoid glucosides, namely gardoside, mussaenosidic acid, 8-epiloganic acid, arborescosidic acid and alpinoside. In addition to these compounds, the plant contained salidroside and a previously unknown caffeoyl phenylethanoid glycoside (CPG) which we have named chionoside J. The structure was elucidated mainly by 1D and 2D NMR spectroscopy to be 2″-(β-glucopyranosyl)-plantamajoside. The distribution of plantamajoside and its derivatives as well as that of carbocyclic iridoids with an 8,9-double bond is briefly discussed, and it is noted that such compounds are mainly confined to the tribe Veroniceae of the Plantaginaceae.

Figure optionsDownload as PowerPoint slideHighlights
► From Veronica beccabunga (brooklime) was isolated chionoside J.
► The structure was shown to be 2″-(β-d-glucopyranosyl)-plantamajoside.
► The distribution of plantamajoside and its derivatives is briefly discussed.