Bisabolene isoprenologues

The serrulatanes possess the same configuration at Cl as the bisabolene isoprenologues and can reasonably be derived from elaboration of the bisabolonium intermediate (205) as shown in... 

Although the sequences presented above are entirely hypothetical, they have proven useful in suggesting the type of skeleton that a newly discovered ring system might contain. This has been the case for the bisabolene isoprenologues and, more importantly, the cedrene isoprenologues. The intermediate role of this skeleton on the sequence leading to the eremanes is predictable. 

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