| This thesis describes research directed toward a synthesis of (5R)- and (5S)-polyandrane. The polyandranes are members of the quassinoid family of natural products isolated from plants of the Simaroubaceae family. Many members of the quassinoid family of natural products have elicited interest due to their medicinal properties, especially bruceantin. Synthetic interest in quassinoids has resulted in publication of numerous total syntheses including the polyandranes and bruceantin.; Our approach for the synthesis of the polyandranes revolves around preparation of a tricyclic intermediate containing a trans-perhydroindan substructure as the first key intermediate. Preparation of the tricyclic intermediate, first carried out in a model system, incorporates a 5-exo-dig radical cyclization as the key bond-forming reaction. Implementation of the chemistry developed in the model system to substrates with the correct C 11 oxidation state, results in an unexpected tetracyclic product. A radical clock is incorporated into the system to circumvent tetracycle formation.; The second major goal is formation of the D ring. Studies toward D ring formation include an ene cyclization, a radical cyclization, and a Tsuji-Trost cyclization. |
