The term pyrrolizidine alkaloids (PAs) describes a group of more than 350 individual compounds that share as a basic structure one of the four necine bases platynecine, retronecine, heliotridine, or otonecine. PAs are produced as secondary metabolites of more than 6000 plant species, belonging to the families of Boraginaceae, Compositae (Asteraceae) and Leguminosae (Fabaceae) and occur world-wi...

Sulfone-substituted γ- and δ-lactams have been prepared in a single step with high diastereoselectivity. Sulfonylglutaric anhydrides produce intermediates that readily decarboxylate to provide δ-lactams with high diastereoselectivity. Substituents at the 3- or 4-position of the glutaric anhydride induce high levels of stereocontrol. Sulfonylsuccinic anhydrides produce intermediate carboxylic ac...

helitropium europaeum l. population garmsar was shown to contain three major alkaloids: heliotrine n-oxide (2), lasiocarpine (4) and lasiocarpine n-oxide (5); and four minor alkaloids: heliotrine (i), europine (3), acetyllasiocarpine (6) and a novel alkaloid acetyllasiocarpine n-oxide (7).

Mankind has been exploiting plant chemicals in the form of potions and poisons for thousands of years. The attitude toward the physiological significance of this plethora of small molecules is reflected in the terminology that was assigned to them: secondary metabolites. Less flattering terms were also assigned: waste products, metabolic leftovers, and excrement. Two schools of thought concerni...

In the last years, several food alerts have identified high levels of pyrrolizidine alkaloids (PAs) in a wide variety products, highlighting their occurrence as concerning safety issue. Currently, there is call to collect new data on PAs matrices that, date, been less studied, well develop sensitive and potent analytical methods that enable determination these compounds at very low concentratio...