Phytochemical Study of Eryngium triquetrum: Isolation of Polyacetylenes and Lignans

Abstract

Phytochemical investigation of the ethyl acetate extract from the aerial parts of <i>Eryngium triquetrum</i> Vahl resulted in the isolation of new polyacetylenes, triquetridiol (<b>6</b>) and <i>trans-</i>epoxy-triquetrol (<b>7a</b>/<b>7b</b>, diastereomeric mixture), and the lignan demethoxy carolignan Z (<b>8a</b>/<b>8b</b>, <i>erythro/threo</i> pair), together with a series of related known metabolites. Additionally, some already reported phenolic and flavonoid compounds were also identified in the extract. Structural elucidation of the new compounds was made by spectroscopic analysis, mainly NMR and mass spectrometry. To the best of our knowledge, this is the first report of polyacetylenes and lignans from <i>E. triquetrum</i>.