Throw your hat in the ring: A highly diastereoselective synthesis of the ABC rings of (-)-norzoanthamine has been achieved starting from the (-)-Hajos-Parrish ketone (see scheme). Three asymmetric quaternary carbon centers on the C ring were constructed by a 1,4-addition, and an intramolecular Diels-Alder reaction provided a trans-decalin scaffold on the AB rings.

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http://dx.doi.org/10.1002/anie.200804544DOI Listing

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