k777

K777 is a potent, orally active, and irreversible inhibitor of cysteine protease, functioning as a potent CYP3A4 inhibitor (IC50 = 60 nM) and a selective CCR4 antagonist, which inhibits chemotaxis. K777 irreversibly inhibits Cruzain, the major cysteine protease of Trypanosoma cruzi, and cathepsins B and L, targeting cathepsin-mediated cell entry and exhibiting broad-spectrum antiviral activity. It inhibits EBOV and SARS-CoV pseudovirus entry with IC50 values of 0.87 nM and 0.68 nM, respectively.

Se2h is a cruzain inhibitor exhibiting potent activity against intracellular amastigotes of Trypanosoma cruzi (EC50< 1 μM, SI> 10), with an inhibitory effect on cruzain of IC50< 100 nM (SI> 5.55). Compared to Benznidazole and cruzain inhibitor K777, Se2h shows superior selectivity and inhibition while its selenazole structure reduces selenium-related toxicity. Se2h demonstrates antiparasitic activity and holds promise for Chagas disease research.