1983 年 41 巻 10 号 p. 941-957
Withanolide, a group of naturally occuring C28 steroidal lactone isolated from the plants of Solanaceae family, has been paid attention for their biological activity, e. g. antitumor and insect antifeedant. The syntheses of jaborosalactones, withaferin A and other several withanolides were achieved. The key steps in the synthesis involve introduction of the desired substituent at C-25 and stereoselective construction of the A/B rings by a facile allyl sulfoxide-sulfenate rearrangement. The biological activities and neighbouring group effects of the A/B ring are also described.