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10-Step Asymmetric Total Synthesis and Stereochemical Elucidation of (+)-Dragmacidin?D.

ABSTRACT: The asymmetric synthesis of dragmacidin?D (1) was completed in 10?steps. Its sole stereocenter was set by using direct asymmetric alkylation enabled by a C2-symmetric tetramine and lithium N-(trimethylsilyl)-tert-butylamide as the enolization reagent. A central Larock indole synthesis was employed in a convergent assembly of the heterocyclic subunits. The stereochemical evidence from this work strongly supports the predicted S configuration at the 6''' position, which is consistent with other members of the dragmacidin family of natural products.

SUBMITTER: Jackson JJ

PROVIDER: S-EPMC4532559 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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10-Step Asymmetric Total Synthesis and Stereochemical Elucidation of (+)-Dragmacidin D.

Jackson Jeffrey J JJ Kobayashi Hiroyuki H Steffens Sophia D SD Zakarian Armen A

Angewandte Chemie (International ed. in English) 20150630 34

The asymmetric synthesis of dragmacidin D (1) was completed in 10 steps. Its sole stereocenter was set by using direct asymmetric alkylation enabled by a C2-symmetric tetramine and lithium N-(trimethylsilyl)-tert-butylamide as the enolization reagent. A central Larock indole synthesis was employed in a convergent assembly of the heterocyclic subunits. The stereochemical evidence from this work strongly supports the predicted S configuration at the 6''' position, which is consistent with other me ...[more]

PMID: 26130270

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