Synthetic Studies on the Viridin Skeleton through Regio- and Stereoselective Functionalization of the AE-Ring Moiety

Abstract

4,5,6,7-Tetrahydroisobenzofurans, corresponding to the AC(D)E ring structure of viridin and equipped with required substituents on the A-ring, were synthesized with high regio- and stereoselectivities via the Diels–Alder adduct of a furan derivative and maleic anhydride. The key steps of this work include the regioselective opening of a tetrahydrofuran ring, a stereoselective epoxidation, and an AlMe₃-mediated regioselective epoxide opening followed by stereoselective C-methylation.

Key words

Diels–Alder reaction - regioselectivity - ring cleavage - tetrahydroisobenzofuran - viridin - furanosteroids

Publication History

Received: 01 April 2021

Accepted after revision: 11 June 2021

Accepted Manuscript online:
11 June 2021

Article published online:
30 June 2021

• References and Notes

• 1 Present addresses: Kenzo Yahata; Max-Planck-Institut für Kohlenforschung, 45470 Mülheim an der Ruhr, Germany. Takashi Ikawa; Gifu Pharmaceutical University, Daigaku-Nishi, Gifu 501–1196, Japan.
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For recent examples of domino dynamic kinetic resolution/IMDA reactions, see:
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