Photocatalytic Stereochemical Editing for the Concise Syntheses of (25<i>S</i>)‐Δ⁷‐Dafachronic Acid, Demissidine, and Smilagenin

Stereochemistry editing serves as an important tool to precisely adjust the desired stereochemical configuration of a molecule. In this study, enabled by photocatalytic stereochemical editing of tertiary C─H bonds of steroids, we have completed concise syntheses of (25S)-Δ⁷-dafachronic acid, demissidine, and smilagenin. The feasibility of regioselectively editing tertiary stereocenters with either very weak α-hydroxyl C─H bonds (in the synthesis of dafachronic acid), α-amino C─H bonds (in the synthesis of demissidine), or with varying steric hindrance (in the synthesis of smilagenin) has been successfully demonstrated.