Cadalane skeleton

Amico, V. Oriente, G. Piattelli, M. Trin li, C. Fattorusso, E. Magno, S. Mayol, L. (1979) Sesquiterpene based on the cadalane skeleton from the brown alga Dilophus fasciola. Exp iaitia, 35, 450-1. 

Cadinene is a trivial name of a number of isomers which occur in a wide variety of essential oils e.g. cubeb oil. Actually, it is derived from the Cade juniper Juniperus oxycedrus L.). The cadalane (4-isopropyl-1,6-dimethyldecahydro-naphthalene) carbon skeleton is the base. Prominent stereochemical isomers are a-cadinene 79, y-cadinene 80 and d-cadinene 81 (Structure 4.23). This group is also known as naphthalene-type sesquiterpenes. 

Only a few compounds have the carbon skeleton of the geranylmenthane cation (471), mostly isolated from genus Helichrysum - e.g., peroxide 474 from roots of H. acutatum (40). Compounds of the prenylgermacrane type (472) have not, so far, been isolated from higher plants however, the bluish-red antibiotic biflorin (475), occurring in the roots of Capraria biflora (105), is an example of a type arising from further cyclization of 472 (cf. cadalanes in Sect. 8.1.3.3.2, Ses-quiterpenoids). 

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