As a result, a racemic synthesis of hermitamides A and B has
been reported using ruthenium catalyzed cross-metathesis reaction
as a key step to install the alkene fragment.4 Subsequently,
enantioselective synthesis of lyngbic acid has been accomplished
by various approaches such as the ring-opening of chiral epoxide,5
lipase mediated kinetic resolution,6 and asymmetric allylation of
the requisite aldehyde.7 In addition, a rhodium catalyzed conjugate
addition of chiral potassium trifluoroalkenylborate has been
employed to construct the side chain of hermitamides.8 Recently,
Sharpless asymmetric epoxidation has successfully been used in
the synthesis of novel malyngamide derivatives.9 Keck allylation
and the stereospecific formation of E-olefin by Johnson–Claisen
rearrangement have been utilized to accomplish the total synthesis
of hermitamides A (1) and B (2).