Total Synthesis of (−)-Acetylaranotin


  • This work was financially supported by the Funding Program for Next Generation World-Leading Researchers (LS008), the KAKENHI, and Grant-in-Aid for Scientific Research (B) (20390003). We thank Dr. M. Isaka (BIOTEC, NSTDA, Thailand) for providing a sample of the natural product and valuable discussion. We appreciate Prof. Y. Iwabuchi (Tohoku University) for the generous gift of 9-azanoradamantane N-oxyl (nor-AZADO).


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The key step in this total synthesis of (−)-acetylaranotin is the efficient formation of the characteristic dihydrooxepine ring from cyclohexenone through an unusual vinylogous Rubottom oxidation and a regioselective Baeyer–Villiger oxidation. (−)-Acetylaranotin is obtained in 22 steps from commercially available L-Cbz-tyrosine (Cbz=benzyloxycarbonyl).