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Synthesis of Demissidine Analogues from Tigogenin via Imine Intermediates.

ABSTRACT: A five-step transformation of a spiroketal side chain of tigogenin into an indolizidine system present in solanidane alkaloids such as demissidine and solanidine was elaborated. The key intermediate in the synthesis was spiroimine 3 readily obtained from tigogenin by its RuO4 oxidation to 5,6-dihydrokryptogenin followed by amination with aluminum amide generated in situ from DIBAlH and ammonium chloride. The mild reduction of spiroimine to a 26-hydroxy-dihydropyrrole derivative and subsequent mesylation resulted in the formation of 25-epidemissidinium salt or 23-sulfone depending on reaction conditions.

SUBMITTER: Wojtkielewicz A

PROVIDER: S-EPMC8509427 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Synthesis of Demissidine Analogues from Tigogenin via Imine Intermediates.

Wojtkielewicz Agnieszka A Kiełczewska Urszula U Baj Aneta A Morzycki Jacek W JW

International journal of molecular sciences 20211008 19

A five-step transformation of a spiroketal side chain of tigogenin into an indolizidine system present in solanidane alkaloids such as demissidine and solanidine was elaborated. The key intermediate in the synthesis was spiroimine 3 readily obtained from tigogenin by its RuO4 oxidation to 5,6-dihydrokryptogenin followed by amination with aluminum amide generated in situ from DIBAlH and ammonium chloride. The mild reduction of spiroimine to a 26-hydroxy-dihydropyrrole derivative ...[more]

PMID: 34639219

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