Aspirin s antiplatelet effects come from its ability to inhibit the synthesis of thromboxane, which otherwise bind platelets together in areas where vessel damage has occurred 4. Measure out 3 g of salicylic acid on an analytical balance, recording its mass to the nearest 0. Platelets prepared from aspirin treated donors did not incorporate any acetylh aspirin radioactivity into the particulate protein for 2 days after drug treatment and did not show full pretreatment uptake of radioactivity for 12 days thereafter. Aspirin is also used longterm to help prevent further heart attacks, ischaemic strokes. Acetylsalicylic acid inhibits prostaglandin synthesis. Position the capillaries in the meltemp apparatus and determine the melting point ranges for each solid. Biological activity analgesic painkiller antipyretic fever reducer antiinflammatory inhibition of the synthesis of prostaglandins side effects. It may be used as a prelab exercise to familiarise students with the reaction they are going to be undertaking and how to set up the equipment or as postlab exercise to reinforce the learning. Calculate the theoretical yield for the esterification reaction synthesis of aspirin from salicylic acid.
Aspirin is one of the most widely used nonprescription drugs in the world, with over 50 million pounds consumed annually. So far, it has been widely accepted that in the aspirin acetylated cox2, pgg2 synthesis is blocked, whereas the acetylated enzyme. Aspirin, or acetylsalicylic acid, is one of the most widely produced drugs in the world. A small amount of a strong acid is used as a catalyst which speeds up the reaction. Aspirin has been used as a medicine by the ancient greeks and the pharaohs of egypt. Prepare a hot water bath by placing 250 ml of tap water in a 400 or 600 ml beaker on a ring stand and heating to 7085 c using a bunsen burner flame. H acetic anhydride cooh salicylic acid o o o o aspirin cooh o oh cooh cooh cooh cooh. To purify the crude aspirin product a recrystallization procedure needed to be performed to remove impurities and to further purify it. Jb smith demonstrated aspirin s inhibition of prostaglandin synthesis craven ll. On this page you can read or download retrosynthesis of aspirin in pdf format. It also controls fevers through a similar mechanism prostaglandin system and the inhibition of. The aspirin product that was collected still contained some impurities. The mechanism of this reaction can be understood by examining the lewis structures of each reagent. Pdf this aim of this experiment focuses on the synthesis of pure aspirin.
The method described before is that followed by most manufacturers to make this chemical. Antiinflammatory inhibition of the synthesis of prostaglandins. If you dont see any interesting for you, use our search form on bottom v. Aspirin s chemical name is acetylsalicylic acid, and it is synthesized from the reaction of acetic anhydride with salicylic acid in the presence of phosphoric acid as a catalyst. After synthesis and analysis, it will be determined if the crude and recrystallized samples were composed solely of either salicylic acid, acetylsalicylic acid, or a combination of both 3.
Propose a reasonable reaction mechanism that supports your answer. Mass of salicylic acid used mass of aspirin obtained percent yield attach sample calculations purity of the aspirin melting point melting point range tlc results compound rf values salicylic acid authenticated aspirin synthesized aspirin fecl 3 test results. Aspirin, platelet function, inflammation 62619 5 the fritsma factor aspirin efficacy agonists 0. Aspirin, also known as acetylsalicylic acid asa, is a medication used to treat pain, fever, or inflammation. Sp11 1021 synthesis of aspirin and oil of wintergreen. Dec 06, 2015 on this page you can read or download retrosynthesis of aspirin in pdf format.
Draw the arrowpushing mechanism for the synthesis of aspirin from salicylic acid. Mechanism of asa benefit in cvd low dose aspirin irreversibly acetylates and inhibits cox1 and only weakly inhibits cox2 in platelets, cox1 inhibition leads to vtxa2 production platelets cannot replenish cox1 no nucleus thus inhibition is permanent for the life of the platelet. Aspirin and the other nsaids do not generally change the course of the disease process in those conditions where they are used for symptomatic relief. Im doing my individual investigation on aspirin, and as part of my plan my teacher has indicated that i need to include the mechanism of the reaction. If you will be calculating actual and theoretical yield, be sure to record how much salicylic acid you actually measured add 6 ml of acetic anhydride and 58 drops of 85% phosphoric acid to the flask.
Prepare two capillaries with small amounts of your crude aspirin product and one capillary with a small amount of pure aspirin. Aspirin was first introduced by the drug and dye firm bayer in 1899. This reaction is the reverse of the synthesis reaction. A year or so later, an inducible cox was identified as a distinct isoform of cox cox2 encoded by a different gene from. These resonance forms will help you understand why a partial positive charge appears on the carbon atom in acetic anhydride and how this results in a new bond forming at that.
Take a small amount of the aspirin tablet and dissolve as much as you can in 3 drops of ethyl acetate. To view pdf files you will need the acrobat viewer available from adobe. In 1971, vane discovered the mechanism by which aspirin exerts its antiinflammatory, analgesic and antipyretic actions. The synthesis of aspirin triggered lipoxin atl by cyclooxygenase2 acetylation is an alternative mechanism of asa, which could explain the effectiveness of asa treatments. Synthesis of aspirin aspirin is the single most manufactured drug in the world. Aspirin is one of the milder and least expensive pain relievers available. In lower doses, aspirin prevents the progression of cardiovascular disease.
By comparison, 200 mgkg acetaminophen raised the threshold for stimulation 4fold in the randall and selitto test for analgesia. It is the most widely used analgesic, and is much preferred over morphine because it does not involve physiological dependence. That is to say, a reaction can only occur until one reactant is. Its activity is substantially altered by aspirin, a nonsteroidal antiinflammatory drug that irreversibly inhibits cox2 by acetylation of its ser530 residue. It is expected that the students will consider a reaction mechanism that proposes a charge separation in the reaction transition state, similar to the one presented in scheme i. These platelets can clot together and become harmful otherwise. Synthesis of aspirin and oil of wintergreen revision f8 page 3 of 7 procedure synthesis of aspirin 1. Cyclooxygenase2 cox2 catalyzes the formation of prostaglandin g2 pgg2 from arachidonic acid aa. This figure mainly reflects purchase of 16,000 tons of aspirin tablets or 80 million tablets a year. Use of aspirin and nsaids in patients with heart disease. Aspirin acetylsalicylic acid is a painrelieving compound familiar to virtually all students. It is also an antiinflammatory agent, providing some relief from the swelling associated with arthritis and minor injuries. Limiting reactants are important in chemical reactions because a reaction cannot proceed without all of the reactants.
Synthesis of aspirin synthesis purification characterization aspirin. Aspirin is a drug which is widely used today to deal with the symptoms of many minor illnesses ranging from general relief from aches and pain. You have been asked to evaluate a simple organic synthesis for aspirin and to determine if the synthesis merits further funding by santa monica pharmaceuticals. As for mechanism of action, the accumulated evidence of recent years indicates that asa. Synthesis of aspirin from salicylic acid and acetic anhydride. Jb smith demonstrated aspirins inhibition of prostaglandin synthesis craven ll. To become familiar with the role of synthetic chemistry through the production of aspirin. Level 1 aspirin synthesis this level provides some background context and guides the user through the steps required to synthesise aspirin. Much of this is believed to be due to decreased production of prostaglandins and txa2.
Aspirin possesses a number of properties that make it the most often recommended drug. Aspirin synthesis your team of scientists has been hired by the drug research division of santa monica pharmaceuticals, a new startup company formed by some smc alumni. The mechanism of action of aspirinthe inhibition of prostaglandin synthesis was elucidated by sir john vane,4 who was awarded the nobel prize in 1982 for. Aspirin s ability to suppress the production of prostaglandins and thromboxanes is due to its irreversible inactivation of the.
Synthesis and decomposition of aspirin chemistry science fair project experiments, chemistry models, exhibition ideas, expo topics for kids and also organics chemistry science ideas for cbse, icse, middleschool, elementary school for 5th, 6th, 7th, 8th, 9th and high school students. Aspirin is a drug that is usually used to relieve minor aches and pain and other medical uses such as antiinflammatory medication. The role of aspirin in cancer prevention michael j. To prepare aspirin, salicylic acid is reacted with an excess of acetic anhydride. This paper describes the first of our organic synthesis experiments, the synthesis, purification, and qualitative spectroscopic characterization of aspirin. Most of us are familiar with esters, but are not aware of their presence in our everyday life. Aspirin is used in the treatment of migraine aspirin is an important part of treatment of those who have had a myocardial infraction heart attack. Consult msds for safety information on all the chemicals you plan to use. Synthesis of acetaminophen from pnitroaniline and acetic anhydride. Do not lose this container or its contents, you will use them later. The effectiveness of aspirin is largely due to its ability to inhibit prostaglandin synthesis. Synthesis of aspirin synthesis purification characterization. Understanding the molecular details of the mechanism that.
Aspirin given shortly after a heart attack decreases the risk of death. This drug was named aspirin and became the most widely used medicine of all time. Pdf preparing a pure aspirin acetylsalicylic acid researchgate. The general reaction equation and the reaction mechanism are as follows. Aspirin acetylsalicylic acid inhibits platelet prostaglandin synthesis and the adp. Acetic anhydride ho paminophenol ho o oh ho ho n h oh o o h oh o h nh acetaminophen. Aspirins chemical name is acetylsalicylic acid, and it is synthesized from the reaction of acetic anhydride with salicylic acid in the presence of phosphoric acid as a catalyst. Aspirin is also an antipyretic compound, which means it reduces fever. You may abbreviate the aromatic ring ar in the intermediates. In the presence of moisture, aspirin may decompose hydrolysis into salicylic acid and acetic acid. In the synthesis of aspirin, sulfuric acid is also used as a catalyst to speed up the reaction wikipedia, sulfuric acid, 20.
Aspirin causes several different effects in the body, mainly the reduction of inflammation, analgesia relief of pain, the prevention of clotting, and the reduction of fever. A greener approach to aspirin synthesis using microwave. Essentially im looking for a proper curly arrow type mechanism for the synthesis of aspirin from salicylic acid 2hydroxybenzoic acid and ethanoic anhydride. The mechanism of the effect of aspirin on human platelets. Calculate the mmol of salicylic acid and acetic anhydride used in the reaction. Aspirin, the wonder drug, is an important chemical worldwide.
Synthesis of aspirin adapted from bettelheim objective. The most recognized mechanism of action of aspirin is to inhibit the synthesis of prostaglandins but this by itself does not explain the repertoire. This is done by irreversibly blocking cyclooxygenase prostaglandin synthase, which catalyzes the conversion of arachidonic acid to endoperoxide compounds. Inhibition of prostaglandin synthesis as a mechanism of action for aspirinlike drugs. He proved that aspirin and other nonsteroid antiinflammatory drugs nsaids inhibit the activity of the enzyme now called. Reaction mechanism suggested for the synthesis of aspirin under.
Reaction mechanism of aspirin synthesis the student room. It is necessary to consider resonance forms of intermediate structures. In this activity you use ethanoic anhydride to convert 2hydroxybenzoic acid into aspirin. H 3 po 4 synthesis of aspirin aspirin is the single most manufactured drug in the world. It is effective in reducing pain it is an analgesic, reducing inflammation antiinflammatory, reducing fever antipyretic, and thinning blood anticoagulant. This experiment teaches the concept of ester formation using a very reactive acid derivative acetic anhydride with an appropriate alcohol salicylic acid. Transfer the salicylic acid into a second 125ml erlenmeyer flask not the one with the water in it, and record the mass of the salicylic acid on your report sheet. Get a printable copy pdf file of the complete article 1. Synthesis and decomposition of aspirin chemistry science.
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