Harold King. A notable contributor to anaesthesia.

Harold King was an analytical chemist of distinction, who worked with Sir Henry Dale and his colleagues in the Medical Research Institute, later the Medical Research Council. He helped to quash the theory that the anaesthetic action of ether was attributable to its impurities. Interest in alkaloids led to the elucidation of the structure of hyoscine, the synthesis of muscarine and the first isolation of crystalline tubocurarine for which he proposed a structural formula, work which influenced Bovet in the synthesis of gallamine. He proposed the synthesis of the homologous series of methonium compounds which included relaxant and hypotensive drugs. His collaboration with Rosenheim was outstanding and opened the way for synthesis of cholesterol and the steroids. He was always encouraging clinicians, and gave a sample of tubocurarine to Ranyard West who was the first to inject d-tubocurarine into a human patient.