セスキテルペノイドの研究 (第4報)

ラクトン環の性質 その1

抄録

The ketone group in C₃-positon of tetrahydrosantonin (II), m.p. 153-156°, was protected as the ethyleneglycol-ketal, the lactone was ruduced by LiAlH₄ to the diol-3-cyloketal (IV), m.p. 149-151°, and further hydrolyzed with an acid to 3-ketodiol (VIII), m.p. 117-118°. The hydroxyl in C₅ of the diol is not benzoylated in the case of 3-cycloketal (IV) while it is benzoylated in the case of the 3-ketone (VIII).