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A study was conducted to examine a stereoselective radical cascade cyclization to 5-alpha-pregnanes. A C-8beta angular hydrogen was accommodated through the cyano group while the chloro ester moeity supported an entry to the geminal hydrogens at C-4. Results indicated the need for a double bond in the steroid nucleus to develop a potential route to d,l-progesterone through a common intermediate.

Racemic norlabdane oxide was successfully synthesized using a stereoselective radical cascade approach. The radical cyclization of a specific polyene with Mn(III) and Cu(II) afforded a sole bicycle product, thereby demonstrating the regiospecificity of the reaction. Acid treatment of the resulting bicycle product yielded a tricycle product exhibiting a modified A-ring norlabdane oxide skeleton.

Intramolecular oxidative radical cyclization is applied in the stereoselective synthesis of d,l-spongiatriol and related metabolites. The technique is used in the synthesis of six chiral centers and the addition of an angular cyanide group. Additional modifications and conversions were undertaken to generate two tetracycles containing a D-furan ring system and the necessary substituents for the synthesis of various spongians.

Research was conducted to study the synthesis of natural acuminolide and 17-O-acetylacuminolide. Sclareolide was transformed into epoxy alcohol while the stereochemistry was determined indirectly at the tricyclic state while an analogous reaction sequence was utilized in an approach to 17-O-acetylacuminolide. Results indicated that the exclusive formation of isomers from cyclizations contradicted acid reactions. They also showed that diacetates were readily separated by chromatography.