Total Synthesis of the Bis-silyl Ether of (+)-15-epi-Aetheramide A.

Synthesis of the macrolactone depsipeptide aetheramide A was attempted by three different approaches. The first approach to form the macrolactone involving macrolactonization to form the C1-C21 bond and the second approach using a ring-closing metathesis (RCM) strategy to form the C10-C11 olefinic bond failed. The third approach starting from R-mandelic acid, involving the RCM reaction to install the C18-C19 ring junction, was successful in assembling the macrolactone.

Total synthesis of (+)-seimatopolide A.

Total synthesis of 10-membered lactone (+)-seimatopolide A is presented from furfural. Key reactions in the present strategy include the effective use of furan as a E-but-2-ene-1,4-dione surrogate, Nagao acetate aldol reaction, and Shiina lactonization.