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Progress toward a Convergent, Asymmetric Synthesis of Jervine.

ABSTRACT: Progress toward a convergent approach for the enantioselective synthesis of the Veratrum alkaloid jervine is presented. The two requisite fragments were stereoselectively and efficiently fashioned from economical and readily available reagents. Key reactions include (a) a highly diastereoselective Ireland-Claisen rearrangement to establish the necessary cis-relationship between the amine and methyl group on the tetrahydrofuran E-ring; (b) a diastereoselective selenoetherification reaction that enabled the assembly of the D/E oxaspiro[4.5]decene in the needed configuration; and (c) an enzymatic desymmetrization of an abundant achiral diol en route to a key four-carbon building block as a practical alternative to a protected Roche ester reduction.

SUBMITTER: Zavesky BP

PROVIDER: S-EPMC7212305 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Progress toward a Convergent, Asymmetric Synthesis of Jervine.

Zavesky Blane P BP De Jesús Cruz Pedro P Johnson Jeffrey S JS

Organic letters 20200414 9

Progress toward a convergent approach for the enantioselective synthesis of the <i>Veratrum</i> alkaloid jervine is presented. The two requisite fragments were stereoselectively and efficiently fashioned from economical and readily available reagents. Key reactions include (a) a highly diastereoselective Ireland-Claisen rearrangement to establish the necessary <i>cis-</i>relationship between the amine and methyl group on the tetrahydrofuran E-ring; (b) a diastereoselective selenoetherification r ...[more]

PMID: 32286835

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