Showing posts with label salicylic acid. Show all posts
Showing posts with label salicylic acid. Show all posts

Tuesday, February 28, 2017

Discovery of salicylic acid by Edward Stone

About 3500 years ago Ebers papyrus recommended a decoction of dried leaves of myrtle to cure rheumatic pains.

Hippocrates favored the juices of the popular tree against eye diseases and those of Willow bark in case of pain in childbirth and against fever. The active ingredient of both these remedies is salicylic acid - aspirin’s active ingredient.

One summer day in 1758, an English clergyman named Edward Stone was walking along a brook near Chipping Norton, past some willow trees. For reasons that are not recorded, he put a strip of the bark to his lips and noticed that it tasted bitter.

He knew that the bitter tasting bark of the South American cinchona tree was used as a treatment for malaria, and argued that willow bark might have similar curative properties.

On June 2, 1763, he read a paper to the Royal Society of London entitles “An Account of the Success of the Bark of the Willow the cure of Agues.” By ague, Stone was referring to what now call malaria, but his use of the word cure was optimistic; what his extract of willow bark actually did was to reduce the feverish symptom of the disease.

He described chewing dried bark from Willow trees: “…Which I have found by experience to be powerful astringent and very efficacious in curing anguish and intermitting disorders.”

The substance was named salicylic acid. But when people suffering from pain took the salicylic acid, it caused severe stomach and mouth irritation. In 1899 German chemist working for Bayer, then a dye company found that acetyl salicylic acid was much convenient to take.
Discovery of salicylic acid by Edward Stone

Saturday, January 20, 2007

The Aspirin

Developed by the Bayer Company, aspirin became the classic ideal of a synthetic drug. It was inexpensive, fast acting, specific and had relatively few serous side effects.

The history of aspirin, dates from early times when salicylates of plant origin were used to deaden pain.

The effects of aspirin-like substances have been known since the ancient Romans recorded the use of the willow bark as a fever fighter.

The leaves and bark of the willow tree contain a substance called salicin, a naturally occurring compound similar to acetylsalicylic acid, the chemical name for aspirin.

Even as far back as 400 B.C. Hippocrates recommended a tea made from yellow leaves.

It wasn't until the 1800's that scientists discovered what was in the willow tree that relieved pain and reduced fever.

On June 2, 1763, Edward Stone, a clergyman read a paper to the Royal Society of London entitles “An Account of the Success of the Bark of the Willow the cure of Agues.” By ague, Stone was referring to what now call malaria, but his use of the word cure was optimistic; what his extract of willow bark actually did was to reduce the feverish symptom of the disease.

The substance was named salicylic acid. But when people suffering from pain took the salicylic acid, it caused sever stomach and mouth irritation.

In 1832, a thirty-seven-year-old French chemist named Charles Gerhardt mixed another chemical with the acid and produced good results, but the procedure was difficult and took a lot of time. Gerhardt decided the new compound wasn't practical, so he set aside.

Sixty-five-years later a German chemist, Felix Hoffmann, was searching for something to relieve his father's arthritis.


He studied Gerhardt's experiments and "rediscovered" acetylsalicylic acid. He first synthesized it in pure form at Bayer in 1897.

Dr. Lawrence Craven, a California general practitioner, in 1948, notices that the 400 men he prescribed aspirin to hadn't suffered any heart attacks.

He regularly recommends to all patients and colleagues that "an aspirin a day" could dramatically reduce the risk of heart attack.

How aspirin worked remained a mystery until 1971 when John Vane at the Institute of Basic Medical Sciences of the University of London and the Royal College of Surgeon of England demonstrated that it blocked prostaglandins synthesis.

He turned again to his bioassay system for the answer and within a few days he had convinced himself and his colleagues that this indeed was the missing mechanism of action.

Aspirin has been shown to prevent bodily synthesis of prostaglandins and this to alleviate the symptomatic portion (fever, pain, inflammation, menstrual cramps) of the body’s immune responses.
The Aspirin

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