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Olefin metathesis-iodoetherification-dehydroiodination strategy for spiroketal subunits of polyether antibiotics.

ABSTRACT: The convergent synthesis of two pentacyclic analogues of the polyether monensin A is described. Although different with respect to the configuration of the alcohol at the 3 position of the six-membered ring of the spiroketal subunit, the configuration at the acetal center in both structures is unchanged and is consistent with the anomeric effect. The key synthetic steps are the coupling of two complex segments via an olefin metathesis, and the subsequent conversion of a dihydroxyalkene to the spiroketal through an iodoetherification-dehydroiodination sequence. The compatibility of these transformations with a variety of functional groups makes the overall strategy appropriate for highly substituted frameworks.

SUBMITTER: Tony KA

PROVIDER: S-EPMC3395214 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Olefin metathesis-iodoetherification-dehydroiodination strategy for spiroketal subunits of polyether antibiotics.

Tony Kurissery A KA Dabideen Darrin D Li Jialiang J Díaz-Hernández Maria Dolores MD Jiménez-Barbero Jesús J Mootoo David R DR

The Journal of organic chemistry 20091001 20

The convergent synthesis of two pentacyclic analogues of the polyether monensin A is described. Although different with respect to the configuration of the alcohol at the 3 position of the six-membered ring of the spiroketal subunit, the configuration at the acetal center in both structures is unchanged and is consistent with the anomeric effect. The key synthetic steps are the coupling of two complex segments via an olefin metathesis, and the subsequent conversion of a dihydroxyalkene to the sp ...[more]

PMID: 19813766

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