Geranyllinalyl pyrophosphate

Sclareol (29) and manool (30) may be derived from a geranyllinalyl pyrophosphate precursor (Fig. 22.9). 

Sclareol (29) and manool (30) (Fig. 22.9) are possibly derived via the intermediacy of a geranyllinalyl pyrophosphate (2) precursor. Formation of the allylic ion (50) permits further cyclization to rimuene (51) and abietic acid (52). The former cation (50) can again cyclize to compounds such as phyllocladene (53) and isophyllocladene (Fig. 22.17) (Oehlschlager and Ourisson, 1967). 

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