Cooling to 8 1 ~ 82℃ and reacting for 2h. After the free salicylic acid is qualified, the temperature is reduced to 65438 03℃, crystals are separated out, filtered, washed, dried, and airflow dried at 65 ~ 70℃ to obtain acetylsalicylic acid.
Aspirin (acetylsalicylic acid) is white crystal or crystalline powder, odorless or slightly acetic acid-flavored, slightly soluble in water, easily soluble in ethanol, soluble in ether and chloroform, and its aqueous solution is acidic.
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Extended data:
Aspirin can relieve headache in a short time by dilating blood vessels, and its curative effect on dull pain is better than that of acute pain. Therefore, the medicine can relieve mild or moderate dull pain, such as headache, toothache, neuralgia, muscle pain and menstrual pain.
At the same time, it can restore (reduce) the set point of hypothalamic thermoregulation center raised by bacterial pyrogen to normal level, so it is also used to reduce fever such as cold and flu. This product can only relieve symptoms, but cannot treat the causes of pain and fever, so other drugs should be used at the same time to participate in the treatment.
The development history of aspirin;
As early as Charles' 1853, Gerhardt synthesized acetylsalicylic acid from salicylic acid and acetic anhydride, but it failed to attract people's attention. From 65438 to 0897, German chemist felix hoffman synthesized it again, and treated rheumatoid arthritis for his father, with excellent curative effect.
1897, felix hoffman did synthesize the main substance of aspirin for the first time, but he succeeded under the guidance of his boss and famous chemist Artur eichengreen, and completely adopted the technical route proposed by eichengreen.
Aspirin was listed in 1898, and it was found that it also has the effect of anti-platelet aggregation, which once again aroused great interest. Aspirin and other salicylic acid derivatives are melt esterified with hydroxyl-containing polymers such as polyvinyl alcohol and cellulose acetate to make them into macromolecules. The anti-inflammatory, antipyretic and analgesic effects of the obtained product are longer than those of free aspirin.
1899 was introduced into clinic by Dreiser and named aspirin. According to documents, the inventor of aspirin was felix hoffman, but in this invention, the Jewish chemist Artur Eichengreen played a very important role. Artur eichengreen's bitter story happened between 1934 and 1949.
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