May & Baker was a British chemical company.
It was started by John May and William Gerrard Baker in Wandsworth, London in 1839. They initially specialized in the manufacture of chemicals derived from Mercury and Bismuth. Over the years they diversified into other chemical fields including Photographic, Pharmaceuticals, Agrochemicals, and chemicals for Research and development.
The company was bought by Établissements Poulenc Frères (later to become Société des Usines Chimiques Rhône-Poulenc) in 1922, and subsequently moved to Dagenham, East London, although they continued to trade under the May & Baker name until the 1980s.
During this time they branched into pharmaceuticals, with one of their major discoveries being Sulphapyridine (M&B693) in 1939. This compound was used to treat Winston Churchill's bacterial pneumonia in 1942 — his condition was extremely poor prior to the drug's application.
Post-war, May & Baker expanded into many countries round the world, particularly Commonwealth ones, and comprised three divisions, Pharmaceuticals, Fine Chemicals and Agrochemicals. The 1960s were a boom time for the company, unofficially known as 'the Brittox Years' after one of its world-leading agrochemicals. There were agrochemical manufacturing sites in Sweet Briar Road, Norwich, Barton Moss in Manchester and Belvedere in Kent, a research station at Ongar in Essex and a Head Office at Regent House in nearby Brentwood.
The Agrochemical division also contained Environmental Products (amenity horticulture) and Garden Care (retail), the latter being sold to Pan Britannica Industries (Sumitomo Group) in 1991. A subsidiary, Hortichem, was based in Ongar.
In 1999 the company was split — the Dagenham site (now just Pharmaceuticals), merged with Hoechst and changed the company name to Aventis, and also instigated the loss of R&D at the site in July 2000. The Norwich site became part of Bayer Agrochemicals. The Nigerian subsidiary, bought out in 2002, remains as May & Baker Nigeria Plc.