Abstract:The base-catalyzed dehydration of hydroxyl compounds is unusually studied in dehydration rections.A specical phytoecdysone,carring a α-hydroxyl group on C11-position,ajugasterone C on treatment with 5% KOH-MeOH solution,eliminated a H2O,then afforded a preduct dacryhainansterone (IV) in over 80% yield at room temperature.