アレロパシー活性セスキテルペノイド, ヘリアンヌオール類の合成

抄録

Heliannuol sesquiterpenoids have been isolated by Macias from the extracts of cultivated sunflowers (Helianthus annuus L. SH-222) and are believed to be involved in the allelopathic action of sunflowers. The characteristic phytotoxic activity, coupled with their unique structural features, has made these terpenoids desirable targets for synthetic chemists. In this article, the total synthetic studies on heliannuol sesquiterpenoids have been reviewed mainly focusing on our experimental endeavor. In the first part, the first enantioselective total syntheses of (-) -heliannuol D and (+) -heliannuol A have been mentioned. Alternative synthesis of (+) -heliannuol D, the natural enantiomer, has also been described. In the next chapter, syntheses of optically active heliannuols A, K, G, H and L were shown. Interestingly, the structures of heliannuols G and H were revised by our total synthesis. In the last chapter, the syntheses of heliannuols E and C and determination of their absolute structures were described.