Page 6 - Medecinal plants clinical

when people were advised to chew on the bark to reduce fever &
inflammation. In the 19th century, phytochemistry began to grow in
Europe, scientists tried to isolate and purify the active components of
willow bark. After many attempts, Joseph Buchner obtained relatively
pure salicin crystals in 1828. By 1838, Italian chemist Raffaele Piria
found a method of obtaining a more potent acid from willow extract,
which he named salicylic acid. In 1853, chemist Charles Frédéric
Gerhardt treated acetyl chloride with sodium salicylate to produce
acetylsalicylic acid for the first time. In 1897, Felix Hofmann at Bayer
company began investigating acetylsalicylic acid as a less-irritating
replacement for standard common salicylate medicines. By 1899,
Bayer had named this drug Aspirin and was selling it around the world.

Figure 1. Synthesis of aspirin from salicylic acid
2. Isolation of penicillin (Figure 2) in 1928 by William Fleming and

large-scale production in 1941 by Florey and Chain.

Figure 2. Structure of penicillin

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