Sesquiterpenes and an intermediate 1α, 6β, 11-eudesmanetriol in the biosynthesis of geosmin from Streptomyces sp.

One new sesquiterpene was isolated from the fermentation broth of Streptomyces sp. and the structure was elucidated by spectral analysis as caryolane-1, 6β-diol (1).  An intermediate 1α, 6β, 11-eudesmanetriol (2) in the biosynthesis of geosmin was also found in this strain which proved sequence for the reactions, especially bicyclization preceding dealkylation.