Design, Synthesis, and Characterization of Brequinar Conjugates as Probes to Study DHODH Inhibition.

Brequinar, a potent dihydroorotate dehydrogenase (DHODH) inhibitor, has been evaluated in multiple clinical trials as a potential treatment for cancer. To further understand brequinar-based DHODH inhibition and DHODH′s therapeutic relevance in cancer, we have developed novel brequinar-based probes. We disclose a 16-step convergent synthesis of the first brequinar-PROTAC and a four-step approach towards the first mitochondrial-directed brequinar probe. A PROTAC and mitochondria-directed probe of brequinar both possess cytotoxicity that is superior to brequinar in a colony formation assay. [ABSTRACT FROM AUTHOR]