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1 a Claisen rearrangement to set the C8, C9, C14 stereo-chemistry and utilizes three successive ring closures (C—* CE—CED) to realize the pentacyclic model rac-5 (Scheme I). 3 While this model study provided important information regarding the elaboration of the CDE ring system, it did not provide latent functionality in ringA for eventual transformation into the substitution pattern present in ring A of bruceantin. Our goal was to prepare chiral, nonracemic keto alcohol 6a that would ultimately lead to (-)-bruceantin and to be able to prepare 6a with sufficient ease and in ample quantity to realize our syn-