Studies on the Constituents of the Aerial Parts of Dioscorea tenuipes FRANCH. et SAVAT. III. 3-Methoxalyldiotigenin 4-Acetate and Its Magnesium Complex

Abstract

The structures of two steroidal substances, G₄ and S₄, isolated³⁾ from the fresh aerial parts of Dioscorea tenuipes FRANCH. et SAVAT. (Dioscoreaceae) were investigated. G₄ mp 217-218° (decomp.), [α]_D-55.0°, was characterized as 3-methoxalyldiotigenin 4-acetate (V), and S₄, mp 205-206° (decomp.), [α]_D+19.0°, was presumed to be a complex (VI) consisting of one mole each of V, Mg(OH)₂, and H₂O. They are first spirostanol methoxalate and its magnesium complex ever found in nature.