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Published on: July 17, 2020
Total Synthesis of (+)-Neopeltolide by the Macrocyclization/Transannular Pyran Cyclization Strategy
Kazuki Nakazato1, Mami Oda1, Haruhiko Fuwa1
1Department of Applied Chemistry, Faculty of Science and Engineering, Chuo University, 1-13-27 Kasuga, Bunkyo-ku, Tokyo 112-8551, Japan.
Abstract:
An 11-step synthesis of (+)-neopeltolide was developed. The C1-C7 carboxylic acid and the C8-C16 alcohol were prepared, each in six steps, from (R)- and (S)-epichlorohydrin, respectively. After esterification, our tandem macrocyclization/transannular pyran cyclization strategy was applied to a stereocontrolled construction of the neopeltolide macrolactone. The side chain was synthesized in six steps from ethyl 4-oxazolecarboxylate through palladium-catalyzed cross-couplings. A Mitsunobu reaction of the neopeltolide macrolactone and the side chain completed the synthesis.
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