Photochemical Preparation of Salicylate/Resorcylate Esters/Amides: Asymmetric Synthesis of SCH 351448
Abstract
This body of work is divided into two parts. The first part describes the development and general application of a photochemical based methodology for the preparation of substituted salicylate/resorcylate esters and amides. Substitued salicylate/resorcylate esters and amides are found in a variety of biologically active natural products. Naturally occurring molecules with these structural moieties are of interest to both the chemistry and biology communities due to their unique structures and biological activities. Preparation of these esters and amides is often a non-trivial task due to a combination of electronic and steric effects. To date, a variety of methods have been developed to access salicylate/resorcylate esters and amides, however many of these methods suffer from limitations such as poor substrate scope or they require the use of harsh conditions. The photochemical based method described herein addresses some of these issues and provides a general method for the efficient preparation of these structural units. The second portion of this thesis is concerned with the asymmetric synthesis of the natural product SCH 351448. This synthesis utilizes a highly convergent approach that takes advantage of the dimeric nature of the natural product. A key step in the sequence involves the photochemical coupling of two analogous fragments to provide the complete carbon skeleton of SCH 351448. Also, an optimized and shortened route to the natural product is presented. Finally, preliminary experiments provide insight into the biological function of the natural product.