1. School of Chemistry, University of Bristol, Bristol, BS8 1TS, UK
2. School of Biochemistry, University of Bristol, Bristol, BS8 1TD, UK
3. Compound Synthesis and Management, Discovery Sciences, Biopharmaceuticals R&D, AstraZeneca, Pepparedsleden 1, 431 83, Mölndal, Sweden
4. School of Natural and Environmental Sciences, Newcastle University, Newcastle Upon Tyne, NE1 7RU, UK