Aspirin
Felix Hoffmann records a pure acetylsalicylic-acid synthesis at Bayer
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The creative brief sent to the image model. These are instructions, not a record of what actually happened.
Original prompt & settings (JSON) ↗The molecule was already more than forty years old. What the laboratory journal records is getting it pure and stable, not inventing it.
An entry in a laboratory journal
A Bayer laboratory journal dated 10 August 1897 records Felix Hoffmann's preparation of acetylsalicylic acid at the company's Elberfeld laboratory.
The reaction acetylated salicylic acid with acetic anhydride, producing a chemically pure and stable form of the compound. Nothing was isolated from a Spiraea plant that day; the starting materials were industrially available chemicals.
Charles Frédéric Gerhardt had already synthesised impure acetylsalicylic acid in 1853.
Whose synthesis?
Hoffmann performed and documented the recorded work, but the intellectual and managerial credit is disputed. Walter Sneader's archival reappraisal concluded that Arthur Eichengrün probably directed the synthesis and was instrumental in getting the compound developed.
Bayer credits Hoffmann; Sneader's BMJ study and the German Patent and Trade Mark Office treat the drug as a team product. Neither Hoffmann nor Eichengrün received German sales royalties, while the pharmacology chief Heinrich Dreser did.
Not yet a medicine, not yet a name
The immediate result was a documented laboratory sample. Pharmacological testing, physician trials, naming, trademark registration and marketing all came afterwards.
The product was neither named nor sold as Aspirin in August 1897: Bayer registered the trademark in Germany on 6 March 1899 and introduced the drug that year.
The familiar story that Hoffmann acted to help his rheumatic father first appeared decades later and is not secure contemporary evidence.
Sources
Researched 24 Aug 2026 5 sources not yet audited Date disputed
How this was checked
Researched from the web into a fact sheet and rewritten from that sheet. This article has not yet had an independent model audit. How the pipeline works →
Date disputed. Sources disagree about when this happened.
What the sources leave uncertain
- The journal date and Hoffmann’s performance of the synthesis are well supported.
- The lone-inventor story is disputed. Bayer credits Hoffmann, while Sneader’s BMJ study and the German Patent and Trade Mark Office conclude that Eichengrün probably played a decisive directing role and that the drug was a team product.
- “First pure and stable form” distinguishes the Bayer preparation from earlier syntheses, but acetylsalicylic acid itself was not a new molecule in 1897.