Synthesis of Sominone and Its Derivatives Based on an RCM Strategy: Discovery of a Novel Anti-Alzheimer's Disease Medicine Candidate "denosomin"

Synthesis of sominone was achieved starting from dehydroepiandrosterone on the basis of an RCM strategy for the construction of a delta-lactone side chain. This synthetic protocol was applied for the synthesis of several analogous derivatives including 1-deoxy-24-norsominone (denosomin), which was revealed to exhibit notable bioactivities for new antidementia chemotherapy, exceeding the original natural compound sominone.