First Asymmetric Total Syntheses and Determination of Absolute Configurations of (+)-Eudesmadiene-12,6-olide and (+)-Frullanolide

The first asymmetric total syntheses of sesquiterpene lactones (+)-eudesmadiene-12,6-olide (<b>1</b>) and (+)-frullanolide (<b>2</b>) have been accomplished from 4-bromo-2-methoxyphenol (<b>5</b>) in 12 and 13 synthetic steps, respectively, and the absolute configurations of these two natural products were determined