Hoffmann, We Have a Problem:
Observing and Gathering Information

The bark of the weeping willow tree.

Once we've identified our problem, figured out just what it is, we must observe and gather information (data) regarding the problem. So let's take a look at just what Felix Hoffmann was able to find out about relieving pain.

Hoffmann and Arthur Eichengrün, having done their homework, would have known that people had many ways of combating pain in 1897, though no method was perfect. Old remedies made from medicinal plants and other sources had been used for centuries. Also, new medicines, at least they were new in the 1800s, had appeared. These were often refined natural drugs, but for the first time one could also buy a few new synthetic drugs at the local apothecary shop. In addition, consumers had to be wary in the 1800s because lots of bogus "snake oil" remedies were being sold as cures for every disease under the sun.

salicylic acid

It was one of those old folk remedies that interested Hoffmann and Eichengrün. For centuries, patients suffering from arthritis pain had realized some relief when they chewed on the bark of the willow tree. Only recently (in Hoffmann's time), chemists had discovered that the active compound of the willow bark was a derivative of salicylic acid. What's more, they learned how to obtain salicylic acid from willow trees and other plants, like the American teaberry plant.

A sodium salicylate   remedy bottle.

This was a popular medication, but it was hard to extract from the plants. What's more, there just weren't enough willow trees and teaberry plants around to produce enough salicylic acid to treat all the people who needed it. So chemists did some clever problem-solving and learned to make salicylic acid from coal tar. (Today,salicylic acid is usually made from petroleum.)

Coal tar was used to make dyes. Thus,it was no surprise that dye companies branched out and started making salicylic acid, and eventually other pharmaceuticals. Large-volume production of salicylic acid brought down the price and made the drug available even to poorer people. But patients still found the salicylic acid to be very irritating to the mouth and stomach, so irritating that it couldn't be taken regularly.

There was something else Hoffmann knew. He knew that other drugs had been made less irritating by altering the chemical structure of their molecules. He knew that if a certain group of atoms called an acetyl group was added to certain drug molecules, the drugs became less irritating. Let's illustrate it. Pretend the green hexagon is an irritating drug, and pretend that the red triangle is an acetyl group.

Now let's attach the acetyl group to our irritating drug. The result? Surprise! A drug that was effective but not irritating! So if adding acetyl groups to drug molecules made them less irritating, then maybe, just maybe...