FIGURE 2.

Tautomerase inhibitors block rhMIF binding to CD74-receptor (A) and the structure of p425 (B). A, inhibition of rhMIF-CD74 interaction by four tautomerase inhibitors (p425, 1D2, 1H2, and 2F10) identified from HTS. Biotinylated rhMIF binding to soluble CD74 was detected colorimetrically (A₄₀₅) with a streptavidin-alkaline phosphatase conjugate and p-nitrophenyl phosphate substrate. The most potent confirmed screening hit was p425 with an IC₅₀ of 0.81 μm, ∼10-fold higher than that of anti-MIF antibody (anti-MIF). B, chemical structure of p425 also known as Chicago Sky Blue 6B.