Isosteviol from steviol

The reverse rearrangement, involving the conversion of the kaurene skeleton to that of the beyerene series, is found in the steviol-isosteviol and gibberellin-8,13-isogibberellin rearrangements (see Scheme 22). Apart from their mechanistic interest, these rearrangements were used in partial syntheses directed at structural correlations. 

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