Pseudoguaianolides. 1. Stereospecific Total Synthesis of the Ambrosanolides dl-Ambrosin and dl-Damsin

Article abstract of DOI:10.1021/ja00379a029

Regio- and stereospecific total syntheses of the sesquiterpene lactones dl-ambrosin (1) and dl-damsin (2) are described.Both syntheses start with bromo ketal ester 8 and proceed via the intermediacy of cyclopentenol 4, the precursor to perhydroazulenone 2