Acetylsalicyclic acid aspirin

Acetylsalicyclic acid, aspirin, inhibits the cyclooxygenase-catalyzed first step in the biosynthesis of prostaglandins, prostacyclins and thromboxanes. These latter substances are responsible for the inflammatory and pyretic effects of infection. It is believed that the chemical inhibition reaction involves the acetylation of the enzyme by the aspirin. 

The case of intramolecular participation in ester hydrolysis has been extensively studied using acetylsalicyclic acid (aspirin) and its derivatives. The kinetic data show that the anion is hydrolyzed more rapidly than the neutral species, indicating that the carboxylate group becomes involved in the reaction in some way. Three mechanisms can be considered ... 

During the nineteenth century, chemists had a good deal of success in isolating and purifying natural products from plant sources. Morphine was isolated as a pure compound from crude opium in 1804. Quinine was isolated from the bark of the cinchona tree in 1820 and was initially employed as a fever reducer. However, its effectiveness against malaria was soon discovered and it found an alternative highly important medical use. Sodium salicylate was isolated from the bark of the willow tree in 1821 and was also shown to have analgesic, antipyretic, and antiinflammatory properties. It took an additional 76 years, until 1897, to synthesize the acetyl derivative, acetylsalicyclic acid, commonly known as aspirin. 

Problem 19.15 Use phenol and any inorganic or aliphatic reagents to synthesize (a) aspirin (acetylsalicyclic acid), (b) oil of wintergreen (methyl salicylate). Do not repeat the synthesis of any compound. ... 

Many of the chemicals used in this course will be unfamiliar to you. Their properties can be looked up in reference books, a very useful one being the Aldrich Catalog Handbook of Fine Chemicals. It is interesting to note that 1,4-dichlorobenzene is listed as a toxic irritant and naphthalene is listed as an irritant. Both are used as moth balls. Camphor, used in vaporizers, is classified as a flammable solid irritant. Salicylic acid, which we will use to synthesize aspirin (Chapter 26) is listed as moisture-sensitive toxic. Aspirin (acetylsalicyclic acid) is classified as an irritant. Caffeine, which we will isolate from tea or cola syrup (Chapter 8), is classified as toxic. Substances not so familiar to you—1-naphthol and benzoic acid—are classified respectively as toxic irritants and irritant. To put things in some perspective, nicotine is classified as highly toxic. ... 

Acetylation of the hydroxy group of salicylic acid gives aspirin, acetylsalicyclic acid. 

Provided Aspirin (acetylsalicyclic acid), phenacetin (acetophenetidin), caffeine (theine 1,3,7-trimethylxanthine), methanol, mobile-phase solution (0.01 M sodium borate + 0.005 M ammonium nitrate). See Experiment 26 for the structures of aspirin, phenacetin, and caffeine. 

We want to determine the acetylsalicyclic acid content of a series of aspirin tablets by titration with NaOH(aq). Each of the tablets is expected to contain about 0.32 g of HC9H7O4. What molarity of NaOH(aq) should we use for titration volumes of about 23 mL (This procedure ensures good precision and allows the titration of two samples with the contents of a 50 mL buret.)... 

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