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A Simple Entry to the 5,8-Disubstituted Indolizidine Skeleton via Hetero Diels-Alder Reaction.

ABSTRACT: The 5,8-disubstituted indolizidines are the largest family of indolizidines isolated from the skin of amphibians. These compounds exhibit interesting biological activities such as noncompetitive blockers of nicotinic receptors. In this paper, we present a short, simple, and general synthesis of these alkaloids based on the hetero Diels-Alder reaction between suitable monoactivated dienes and Δ¹-pyrroline as the dienophile. The selectivity of the process is explained based on computational studies. Concise synthesis of the indolizidine alkaloid 181B from a hetero Diels-Alder reaction was accomplished in four steps.

SUBMITTER: Rodriguez-Caro JF

PROVIDER: S-EPMC10647431 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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A Simple Entry to the 5,8-Disubstituted Indolizidine Skeleton via Hetero Diels-Alder Reaction.

Rodríguez-Caro Juan Francisco JF Afonso María M MM Palenzuela José Antonio JA

Molecules (Basel, Switzerland) 20231028 21

The 5,8-disubstituted indolizidines are the largest family of indolizidines isolated from the skin of amphibians. These compounds exhibit interesting biological activities such as noncompetitive blockers of nicotinic receptors. In this paper, we present a short, simple, and general synthesis of these alkaloids based on the hetero Diels-Alder reaction between suitable monoactivated dienes and Δ<sup>1</sup>-pyrroline as the dienophile. The selectivity of the process is explained based on computati ...[more]

PMID: 37959735

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