Late-stage C-H activation of spiropiperidines via evolved P450BM3 mutants and its application to fragment-based drug discovery

Thesis

This thesis describes the synthesis of spirocyclic piperidines, specifically 6-azaspiro[4.5]decane and 7-azaspiro[4.5]decane, and the late-stage functionalisation of the synthesised piperidines via P450BM3 mutants. Utilisation of the newly-installed hydroxyl group as a synthetic handle was also explored, with the aim of demonstrating the potential of P450BM3 catalysis to Fragment-Based Drug Discovery.

Chapter 1 provides an introduction to Fragment-Based Drug Discovery and a review of the major synthetic studies towards spirocyclic piperidines. Subsequently, the significance of C−H functionalisation and the various aspects of P450BM3 applications are discussed.

Chapter 2 describes the synthesis of 6-azaspiro[4.5]decane and its substrate engineering to access hydroxylated products at various unactivated positions. Molecular Dynamics simulations and molecular docking were employed to investigate the underlying ligand-protein interactions.

Chapter 3 describes the synthesis of 7-azaspiro[4.5]decane and its substrate engineering to access hydroxylated products. Analogous to Chapter 2, computational methods were also employed to study ligand-protein interactions.

Chapter 4 explores the utilisation of the hydroxyl group introduced by P450BM3 mutants as a synthetic handle for functional group diversification. Numerous synthetic reactions were performed and the results are discussed.

Finally, Chapter 5 details the protein engineering of P450BM3 mutants to optimise the conversion and selectivity of a selected metabolite via docking-guided mutagenesis. Computational and experimental results were compared by considering different factors in the docking algorithms.

Authors: Lee, KWA

• DOI: 10.5287/ora-or7oajxk2
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Keywords: spiropiperidines; late stage CH functionalisation; late stage CH activation; biocatalysis; P450; cytochrome P450; P450BM3; CH activation
• Subjects: Chemistry, Organic