駆虫薬の研究 第24報

4-Norsantoninの合成研究 その6 4-Norsantoninの合成

抄録

3-Oxo-4-noreusantona-1, 4-dienic acid and its 11-epi compound were submitted to lactonization by heating with selenium dioxide and rac-4-nor-α-santonin (lactone: trans) and rac-4-nor-β-santonin (lactone: trans) were obtained. Both rac-4-norsantonins were submitted to rearrangement through treatment with acetic anhydride and sulfuric acid from which rac-4-nor-α-desmotroposantonin acetate and rac-4-nor-β-desmotroposantonin acetate were obtained, which were saponified with sodium carbonate respectively to rac-4-nor-α-desmotroposantonin and rac-4-nor-β-desmotroposantonin, to confirm their respective structures. It was found that rac-4-nordesmotroposantonin acetate tended to undergo isomerization at C₁₁ during saponification with alkali.