Pyrrolizidine alkaloid

Pyrrolizidine alkaloids are a group of naturally occurring alkaloids based on the structure of pyrrolizidine, of which there are over 300 known examples. They are found very frequently in plants in the Boraginaceae, Compositae, Orchidaceae and Leguminosae families; less frequently in the Convolvulaceae and Poaceae,and in at least one species in the Lamiaceae. Pyrrolizidine alkaloids are hepatotoxic, that is, potentially damaging to the liver. It may cause the onset of Hepatic veno-occlusive disease.