Abstract
Dihydrofolate reductase (DHFR) is an enzyme that has a role in the synthesis of tetrahydrofolate and is used as a target for antineoplastic, antiprotozoal, antifungal, and antimicrobial action. The nicotinamide adenine dinucleotide phosphate-dependent reduction of dihydrofolate to tetrahydrofolate by catalysis of DHFR inhibitors plays an essential role in the synthesis of numerous amino acids. In this chapter, a quantitative structure-activity relationship study on dihydroreductase inhibitors is included.