Eudesmadiene-12,6-olide

Seco-14-deoxyparsonsianine, S-20025 1,2-Secodihydromicromelin, S-30036 1,10-Seco-3.5( 10)-eudesmadien-12,6-olid-1 -oic acid, S-20026... 

Fig. 58 Liao s asymmetric syntheses of (+)-eudesmadiene-12,6-olide and (+)-frullanolide...

In 2013, Liao reported the first asymmetric total syntheses of the sesquiterpenoid lactones (+)-eudesmadiene-12,6-olide and (+)-fruUanolide, which were based oti an initial dearomatization of 4-bromo-2-methoxyphenol 240 into the corresprMidmg MOB 241 (Fig. 58) [129]. An asymmetric Diels-Alder reaction wifli the chiral furan R)-2A2 furnished the bicyclo[2.2.2]octenone 243 in good yield with high chemo-, regio-, and stereoselectivities. This compound was further transformed in a few steps to reach (+)-eudesmadiene-12,6-olide, whose m-decalin core was elaborated by a high-yielding anionic oxy-Cope rearrangement of the allylic alcohol 244 (Fig. 58) [129]. 

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