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A convergent approach to batzelladine alkaloids. Total syntheses of (+)-batzelladine E, (-)-dehydrobatzelladine C, and (+)-batzelladine K.

ABSTRACT: We recently reported a convergent strategy to access the polycyclic guanidinium alkaloid (+)-batzelladine B via an aldol addition-retro-aldol-aza-Michael addition cascade. Here we describe the application of this approach toward the total syntheses of (+)-batzelladine E, (-)-dehydrobatzelladine C, and (+)-batzelladine K. The identification of suitable methods to functionalize a common tropane core by electrophilic alkynylation and nucleophilic 1,2-addition were essential to generalizing this approach. We provide evidence for the intermediacy of an acylallene species in the cascade reaction.

SUBMITTER: Economou C

PROVIDER: S-EPMC8078486 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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A convergent approach to batzelladine alkaloids. Total syntheses of (+)-batzelladine E, (-)-dehydrobatzelladine C, and (+)-batzelladine K.

Economou Christos C Romaire Justin P JP Scott Tony Z TZ Parr Brendan T BT Herzon Seth B SB

Tetrahedron 20180418 26

We recently reported a convergent strategy to access the polycyclic guanidinium alkaloid (+)-batzelladine B via an aldol addition-retro-aldol-aza-Michael addition cascade. Here we describe the application of this approach toward the total syntheses of (+)-batzelladine E, (-)-dehydrobatzelladine C, and (+)-batzelladine K. The identification of suitable methods to functionalize a common tropane core by electrophilic alkynylation and nucleophilic 1,2-addition were essential to generalizing this app ...[more]

PMID: 33911315

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