CAY10761 is an inhibitor of ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1; IC50s = 467 and 429 μM for the human and snake venom enzymes, respectively).1,2 It also inhibits mushroom tyrosinase (Ki = 1.9 μM) and urease from jack bean, P. mirabilis, and B. pasteurii (IC50s = 0.093, <0.125, and 0.089 mM, respectively, at pH 8.2).3,4 |1. Khan, K.M., Fatima, N., Rasheed, M., et al. 1,3,4-Oxadiazole-2(3H)-thione and its analogues: A new class of non-competitive nucleotide pyrophosphatases/phosphodiesterases 1 inhibitors. Bioorg. Med. Chem. 17(22), 7816-7822 (2009).|2. Onyedibe, K.I., Wang, M., and Sintim, H.O. ENPP1, an old enzyme with new functions, and small molecule inhibitors - A STING in the tale of ENPP1. Molecules 24(22), E4192 (2019).|3. Ghani, U., and Ullah, N. New potent inhibitors of tyrosinase: Novel clues to binding of 1,3,4-thiadiazole-2(3H)-thiones, 1,3,4-oxadiazole-2(3H)-thiones, 4-amino-1,2,4-triazole-5(4H)-thiones, and substituted hydrazides to the dicopper active site. Bioorg. Med. Chem. 18(11), 4042-4048 (2010).|4. Amtul, Z., Rasheed, M., Choudhary, M.I., et al. Kinetics of novel competitive inhibitors of urease enzymes by a focused library of oxadiazoles/thiadiazoles and triazoles. Biochem. Biophys. Res. Commun. 319(3), 1053-1063 (2004).