An imide of Kemp's acid was synthesised. Ultraviolet spectroscopy was used to monitor its ring-opening reaction in alkaline solution to an amide, which was found to be stable in its fully ionised state at the high pH. The reactions of the amide on reduction in pH to neutrality were then also studied by UV spectroscopy and showed a 2 phase reaction which does not involve any reformation of imide. The first phase is likely to be the hydrolysis of the amide via neighbouring group catalysis by a carboxylic acid group to form anhydride and amine, a reaction which has potential in anti-tumour prodrug application because it should be highly sensitive to pH and thereby faster at the higher pH of tumour tissue than in healthy tissue. Further study to analyse the detail of the reactions by NMR spectroscopy will now follow and accurate rate measurements of relevance to prodrug application will be undertaken.

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