Pyrrolizidine alkaloids from Echium setosum and Echium vulgare

The major pyrrolizidine alkaloids (PAs) of Echium setosum and Echium vulgare were isolated and characterized as echimidine and a tigloyl isomer of echimidine. 3'-Acetylechimidine was identified in E. vulgare as a major new PA on the basis of MS and 1H and 13C NMR. Sixteen further alkaloids were recorded by GLC-MS in the reduced alkaloid extracts.