Y-Muurolene

Sampling time 60 min extraction temperature 80°C. Monoterpenes a-pinene, p-myrcene, a-phellandreneand limonene sesquiterpenes a-cubebene, a-copaene, p-elemene, p-caryophyllene, a-humulene, y-muurolene, p-eudesmene and caryophyllene oxide diterpenes cembrene A and isoincensole acetate. 

Previous studies (Z) showed evidence for the presence of at least 20 sesquKerpene hydrocarbons in pineapple. These researchers identified 7 sesquiterpenes (1 tentative). We confirmed the presence of 3 of the sesquiterpenes and identified p-copaene, y-muurolene, a- and p-selinene in addition. Mass spectral data indicated the presence of other sesquiterpene hydrocarbons and oxygenated sesquiterpenes which we have been unable to characterize at present. 

In the biosynthesis of tutin (57) the involvement of copaborneol (56) has been demonstrated. As expected, only one tritium atom was incorporated from [2- C,3R,4R- H]mevalonate. Unfortunately, it is still not clear whether the biosynthesis involves a cadinene system or a germacrene system. The cadinene sesquiterpene, y-muurolene (58), and caryophyllene (59) are formed in Mentha piperitaf The labelling of the latter terpenoid (% from [2- C]mevalonate... 

In addition to common six-membered rings such as in the cadinenes, one classic bicyclic sesquiterpene is caryophyllene, which has a nine-membered ring and cyclobutane ring. Additional unsaturation provides aromatic bicyclic sesquiterpenoids such as vetivazulene and guaiazulene. Examples are caryophyllene, y-muurolene, petasin, Ipomeamarone, carotol, helminthosporal, avocettin, alkaloids of Nuphar, and mycophenolic acid. 

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