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 Discovery of Aspirin

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PostSubject: Discovery of Aspirin   14/11/2010, 12:45 pm





Aspirin or acetylsalicylicacid, is a derivative of salicylic acid that is a mild, nonnarcoticanalgesic useful in the relief of headache and muscle and joint aches.The drug works by inhibiting the production of prostaglandins, bodychemicals that are necessary for blood clotting and which alsosensitize nerve endings to pain. The father of modern medicine was Hippocrates,who lived sometime between 460 B.C and 377 B.C. Hippocrates was lefthistorical records of pain relief treatments, including the use ofpowder made from the bark and leaves of the willow tree to help healheadaches, pains and fevers. By 1829, scientists discovered that it was the compound called salicin in willow plants which gave you the pain relief. Accordingto "From A Miracle Drug" written by Sophie Jourdier for the RoyalSociety of Chemistry: "It was not long before the active ingredient inwillow bark was isolated; in 1828, Johann Buchner, professor ofpharmacy at the University of Munich, isolated a tiny amount of bittertasting yellow, needle-like crystals, which he called salicin. TwoItalians, Brugnatelli and Fontana, had in fact already obtained salicin in 1826, but in a highly impure form. By 1829, [French chemist] Henri Leroux had improved the extraction procedure to obtain about 30g from 1.5kg of bark. In 1838, Raffaele Piria[an Italian chemist] then working at the Sorbonne in Paris, splitsalicin into a sugar and an aromatic component (salicylaldehyde) andconverted the latter, by hydrolysis and oxidation, to an acid ofcrystallised colourless needles, which he named salicylic acid." Henri Leroux had extracted salicin, in crystalline form for the first time, and Raffaele Piria succeeded in obtaining the salicylic acid in its pure state. Theproblem was that salicylic acid was tough on stomachs and a means of'buffering' the compound was searched for. The first person to do sowas a French chemist named Charles Frederic Gerhardt. In 1853,Gerhardt neutralized salicylic acid by buffering it with sodium (sodiumsalicylate) and acetyl chloride, creating acetylsalicylic acid.Gerhardt's product worked but he had no desire to market it andabandoned his discovery.
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