Generality
Sulfonamides (also known as sulfonamides) are drugs antibacterial chemotherapy drugs obtained by chemical synthesis, unlike antibiotics which have natural origins.
Sulfonamides - General Chemical Structure
From a chemical point of view, these antimicrobials are sulfonamides that derive from azo dyes.
Sulfonamides were among the first antibacterials to be marketed and used in therapy.
Nowadays, however, the use of sulfonamides has decreased in favor of antibiotics such as, for example, penicillins or cephalosporins. However, their relatively low cost means that these antimicrobials still find a place in the market for anti-infective agents.
The discovery of sulfonamides
The discovery of the "antimicrobial activity of sulfonamides occurred by chance in the mid-1930s".
It all began when the German chemist Gerhard Domagk began to study the "activity of a particular azo dye, the"Prontosil red'.
Domagk hoped that this dye could be retained by certain types of bacterial cells and not by human cells (similar to what happened with the Gram stain method), in an attempt to obtain a potential poison against bacteria that were able to retain that same dye. However, the red Prontosil proved to be absolutely ineffective in the tests in vitro. Instead, it proved effective in vivo, in the treatment of streptococcal infections in mice.
A few years later, in France, chemists and pharmacologists Jacques Tréfouël, Daniel Bovet and Federico Nitti undertook studies on red Prontosil.
Chemists found that the urine of mice treated with the dye was effective in inhibiting bacterial growth in vitro, which was not the case when using red Prontosil as such.
The fractionation of the urine of mice treated with red Prontosil led to the "identification and isolation of the compound with antibacterial activity: the" amide of the para-aminobenzenesulfonic acid (or p-aminobenzenesulphonic acid), better known as sulfonamide.
The researchers came to understand that the red Prontosil itself was not endowed with antibacterial activity, but - once taken by the mouse - it underwent a metabolic degradation in its liver which led to the synthesis of the antibacterial molecule itself, that is to the synthesis of the sulfonylamide. . Therefore, today, red Prontosil would be considered a prodrug.