Brequinar derivatives and species-specific drug design for dihydroorotate dehydrogenase

Brequinar analogs were evaluated through bioassays and in silico screening as species-specific inhibitors of dihydroorotate dehydrogenase (DHODH). A class of analogs known to not inhibit human DHODH dock well to Plasmodium falciparum DHODH. Therapeutic agents brequinar sodium and leflunomide (Arava™) work by binding in a hydrophobic tunnel formed by a highly variable N-terminus of family 2 dihydroorotate dehydrogenase (DHODH). The X-ray crystallographic structure of an analog of brequinar bound to human DHODH was determined. In silico screening of a library of compounds suggested another subset of brequinar analogs that do not inhibit human DHODH as potentially effective inhibitors of Plasmodium falciparum DHODH.