Sulfa drug analogs

Control of tuberculosis, long one of the scourges of mankind, began with the introduction of effective antibacterial agents. Thus, this disease was treated initially with some small measure of success with various sulfa drugs the advent of the antibiotic, streptomycin, provided a major advance in antitubercular therapy, as did the subsequent discovery of isoniazid and its analogs. 

Sulfonamides are structural analogs of PABA that competitively inhibit bacterial synthesis of folic acid (see p. 371). Because purine synthesis requires THF as a coenzyme, the sulfa drugs slow down this pathway in bacteria. 

Sulfa drugs, which are used to treat certain bacterial infections, are analogs of para-aminobenzoic acid. They prevent growth and cell division in bacteria by interfering with the synthesis of folate. Because we cannot synthesize folate, sulfa drugs do not affect human cells in this way. 

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