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Total syntheses of ent-hypocoprin A and ent-hypocoprin B.

ABSTRACT: This study reports the stereoselective total syntheses of the antipodes of the unique 3/10 bicyclic skeletal sesquiterpenoids, namely, hypocoprin A and hypocoprin B. The synthesis involved conjugate addition accelerated by trimethylsilyl chloride, construction of the ten-membered ring via the intramolecular S_N2 reaction promoted by 1,8-diazabicyclo[5.4.0]undec-7-ene, and osmium-mediated π-facial selective dihydroxylation to functionalize the 1,1-disubstituted alkene.

SUBMITTER: Ota K

PROVIDER: S-EPMC9169068 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Total syntheses of ent-hypocoprin A and ent-hypocoprin B.

Ota Koichiro K Watanabe Taiki T Igarashi Shuntaro S Okazaki Shinnosuke S Kamaike Kazuo K Miyaoka Hiroaki H

RSC advances 20220606 26

This study reports the stereoselective total syntheses of the antipodes of the unique 3/10 bicyclic skeletal sesquiterpenoids, namely, hypocoprin A and hypocoprin B. The synthesis involved conjugate addition accelerated by trimethylsilyl chloride, construction of the ten-membered ring via the intramolecular SN2 reaction promoted by 1,8-diazabicyclo[5.4.0]undec-7-ene, and osmium-mediated π-facial selective dihydroxylation to functionalize the 1,1-disubstituted alkene. ...[more]

PMID: 35754888

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