Chris Ramsden

Biography

I was born in Manchester, UK in 1946. I graduated from Sheffield University and received my PhD (W. D. Ollis) in 1970 and DSc in 1990. After post-doctoral work at the University of Texas (M. J. S. Dewar)(1971-3) and University of East Anglia (A. R. Katritzky)(1973-6), I worked in the pharmaceutical industry. I moved to Keele University as Professor of Organic Chemistry in 1992. My research interests are heterocycles and three-centre bonds and applications of their chemistry to biological problems.

Research and scholarship

Recent research activities have been focussed on the copper-containing enzyme tyrosinase, which is responsible for oxidising phenols in the early stages of the biosynthesis of the pigment melanin. We have investigated aspects of the subtly different mechanism by which tyrosinase oxidises phenols and catechols by designing and synthesising appropriate substrates. More recently we have investigated the long-standing problem of why catechols slowly inhibit tyrosinase and have proposed a reductive-elimination mechanism that leads to irreversible formation of copper(0) in the active site. This work has lead to the investigation of new ortho-quinone chemistry and the formation of new heterocyclic systems.

We are also interested in imidazole derivatives. Simple imidazole derivatives are useful building blocks for more complex natural product analogues. We are particularly interested in the chemistry of aminoimidazoles. Although 5-aminoimidazole ribonucleotide (AIR) is an intermediate in the biosynthesis of purines, the chemistry of simple aminoimidazoles has received little study and we have found them to be useful intermediates for the synthesis of a variety of interesting new molecules. Targets include peptide analogues, oligonucleotide analogues, antiviral agents and anticancer compounds.

We have a long-standing interest in the chemistry of molecules that can only be represented by hypervalent or dipolar structures. Molecules of this type form a very large class of possible structures and they can all be considered to contain three-centre four-electron bonds. This diverse family of structures includes, for example, heterocyclic pyridinium-3-olates and xenon difluoride. Although diverse, because of their similar bonding, molecules containing three-centre four-electron bonds undergo similar general types of reaction and we are interested in exploring applications of these reactions to achieve useful new methodology. Current interests include the use of the cheap and non-toxic (diacetoxyiodo)benzene in organic synthesis and fluorination using xenon difluoride.

Teaching

Year 1

• CHE-10014 - Inventions and Society
• CHE-10002 - Basic Organic Chemistry (Module Leader)
• CHE-10026 - Basic Organic Chemistry for Life Sciences (Module Leader)
• PHA-10010 - Pharmaceutical Chemistry
• PHA-10011 - Drug Discovery and Use

Year 2

• CHE-20005 - Drug Design Based on Biological Targets (Module Leader)

Year 3

• CHE-30006 - Synthesis Kinetics and Mechanism
• CHE-30007 - Medicinal and Biomolecular Chemistry (Module Leader)
• CHE-30008 - Organic Radicals