Ivorenolide B, an Immunosuppressive 17-Membered Macrolide from Khaya ivorensis: Structural Determination and Total Synthesis

Ivorenolide B (1), an unprecedented 17-membered macrolide featuring conjugated acetylenic bonds and four chiral centers, was isolated from Khaya ivorensis. The structure of 1 was fully determined by spectroscopic analysis and total syntheses of its four most possible stereoisomers. Compound 1 showed significant immunosuppressive activity.