Verbascoside, synthetic derivatives and other glycosides from Argentinian native plant species as potential antitumoral agents.

A phytochemical study was performed on three native plant species from the central-western zone of Argentina: Grisebach Torr. & A. Gray and L. We could obtain verbascoside () from . From , we could obtain 1, 5, 9--deoxyloganic acid () L. Finally, we could isolate 2--(-rhamnopyranosyl)-3-angeloyloxy-15-acetyloxy-7,13(14)--dien--labdane () and 2--(-rhamnopyranosyl)-3--angeloyloxy-15-hydroxy-7,13(14)--dien--labdane () from . Moreover, three derivatives from , and one semi-synthetic derivative from , were prepared. PCR reaction was used to analyse the activity against DNA polymerase and cell culture to determine cytotoxicity and antitumoral activity. Verbascoside ( was strongly active in the nanomolar scale (IC = 356 nM) against DNA polymerization. Moreover, verbascoside was also strongly active in the nanomolar scale against human melanoma cell line (IC = 256 nM) and human colorectal cell line (IC = 320 nM). Furthermore, derivatives and were cytotoxic against both cancer cell lines.