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A full account of studies that culminated in the total synthesis of both antipodes and the assignment of its absolute configuration of Saudin, a hypoglycemic natural product. Two approaches are described, the first proceeding though bicyclic lactone intermediates and related second monocyclic esters. The former was obtained via asymmetric Diels–Alder cycloaddition and the latter by an asymmetric annulation protocol. Both approaches employ a Lewis acid promoted Claisen rearrangement, with the successful approach taking advantage of bidentate chelation to control the facial selectivity of the key Claisen rearrangement.

In the course of synthetic studies aimed at the elaboration of highly funtionalized ketone 1, we observed what appeared to be an extremely rare example of the addition of a trialkylborane to a carbonyl group. We were able to confirm the initial spectroscopic structural assignment by X-ray crystallography. Some preliminary mechanistic experiments suggest that the addition occurs directly in the absence of oxygen prior to oxidation of the trialkylborane during workup.

A series of diphenyl ethers was prepared and evaluated for androgen receptor antagonist activity in human androgen receptor binding and cellular functional assays. Analogs with potent in vitro activities were evaluated for topical in vivo efficacy in the Golden Syrian Hamster ear model. Several compounds showed reduction in wax esters in this validated animal model.