Title: sulfa drug | Infoplease
Headings: sulfa drug
sulfa drug
Content: sulfa drug | Infoplease
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sulfa drug
Enter your search terms: sulfa drug, any of a class of synthetic chemical substances derived from sulfanilamide, or para-aminobenzenesulfonamide. Sulfa drugs are used to treat bacterial infections, although they have largely been replaced for this purpose by antibiotics; some are also used in the treatment of diabetes. Because sulfa drugs were first used to elucidate ways in which substances can interfere with the metabolism of invading microorganisms, they are of historical interest. The parent compound, para-aminobenzenesulfonamide, was synthesized in 1908 by Paul Gelmo, an Austrian industrial chemist. In 1932 the German chemist Gerhard Domagk discovered that the dye Prontosil had antagonistic properties against a wide range of bacteria, and in 1935 it was found that the sulfanilamide portion of the Prontosil molecule was responsible for its antibacterial effect. In 1940 it was shown that sulfanilamide inhibited the action of the physiological substance para-aminobenzoic acid, which bacteria need to synthesize folic acid. The idea that the two substances were antagonists led to a theory of the mechanism of action of drugs: Many chemotherapeutic substances compete with structurally similar substances that are necessary to the metabolism of invading microorganisms.