Polar compounds from Parentucellia viscosa (L.) Caruel from Sardinia.

In this work, we examined a sample of Parentucellia viscosa from Sardinia island, showing similarities and differences of the secondary metabolite content with respect to previous study conducted on an accession of continental origin, and also with Bellardia trixago, a species very close to Parentucellia. In this aspect, the proximity between these species, previously stated by a phylogenetic study, was confirmed by a phytochemical approach. Within the non-iridoidic fraction a chiral polyol (mannitol) and two aromatic acids (benzoic acid and gallic acid) were evidenced. These two acids are not common in Scropulariaceae since they have been reported only from a few species, and it is worth to note that gallic acid was never reported from the Orobanchaceae family.