Constructive innovation of approaching bicyclo[3.2.1]octane in ent-kauranoids

Abstract In this Digest, innovative strategies and tactics attributed to construct a full 6–6-fused bicyclo[3.2.1]octane framework of ent -kauranoids are highlighted. Although the first synthesis of ent -kaurene was reported fifty years ago, modern synthetic methods continue to sustain this field to the frontier of synthetic chemistry. Recent advances implemented new perspectives in the construction of bicycle[3.2.1]octane skeleton as well as the overall efficiency of synthesis. Biogenesis of ent -kaurene was recently revisited by comprehensive computational analysis. An updated proposal argued that ent -beyerane is derived from ent -kauranyl cation since the secondary carbocation is energetically unfavorable, which may throw light on new experimental design and further biomimicry study to better understand the origin of this vast category of ent -kauranoids.

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