Synthesis of the Core Structure of the Cyclocitrinols via SmI₂-Mediated Fragmentation of a Cyclopropane Precursor

Abstract

The first synthetic entry towards the cyclocitrinols, a new class of natural products possessing a steroid-analogue structure with a characteristic bicyclo[4.4.1]undecane AB ring system, was elaborated. In the key step, a cyclopropanated intermediate (prepared from dehydroepiandrosterone) was subjected to reductive fragmentation (using SmI₂ in THF).

Key words

steroids - samarium diiodide - stereoselective synthesis - fragmentation - natural products

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