Indanone sesquiterpenes

Some older examples of this type of process include the studies of Marko on the synthesis of pseudomonic acid C analogues [118], the preparation of indanones by Snider [119], and synthesis of the skeleton of the sesquiterpenes khusiman and zi-zaen by Wenkert and Giguere and their coworkers [120, 121]. 

The 1-indanone derivatives isolated from ferns are designated as pterosins and their glycosides as pterosides (SOS), Pterosins belong to the so-called illudalane type of sesquiterpenes which possess carbon skeleton 413. Illudalanes are seco-illudanes and illudanes possess carbon skeleton 414. 

Fukuoka, M., M. Kuroyanagi, K. Yoshihira, and S. Natori Chemical and Toxicological Studies on Bracken Fern, Pteridium aquilinum var. latiusculum. II. Structures of Pterosins, Sesquiterpenes Having 1-Indanone Skeleton. Chem. Pharm. Bull. (Japan) 26, 2365 (1978). 

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