Total synthesis of optically active monocrotaline, a carcinogenic pyrrolizidine alkaloid possessing an eleven-membered retronecine dilactone

Article abstract of DOI:10.1016/S0040-4020(01)88350-2

A total synthesis of the natural enantiomer of monocrotaline (1), a representative of carcinogenic pyrrolizidine alkaloids having an 11-membered retronecine dilactone was achieved through regioselective coupling of (+)-retronecine (3) and the optically active protected necic acid 8, the latter being prepared enantioselectively from the meso-diester 11.