Hexa-D-arginine TFA (Furin Inhibitor II TFA) is an inhibitor of furin (Ki values are 0.106, 0.58 and 13.2 μM for furin, PACE4 and PC1 respectively).

Decanoyl-Arg-Val-Arg-Lys-chloromethylketone (DEC-RVRK-CMK) is a small, synthetic, irreversible cell-permeable competitive inhibitor of furin that exhibits strong antiviral activity against Zika virus (ZIKV) and Japanese encephalitis virus (JEV) [1].

Subtilisin/Kex2p-like proprotein convertase inhibitor; blocks activity of all seven convertases (PC1, PC2, PC4, PACE4, PC5, PC7 and furin). Abolishes proET-1 processing in endothelial cells; inhibits regulated secretion of the neuronal polypeptide VGF in

Histatin-3, a 32-amino-acid peptide, exhibits potent antimicrobial activities and serves as a substrate for proprotein convertase 1 (PC1), where it is primarily cleaved at a site carboxy-terminal to Arg25 (HRGYR↓SN). Additionally, it acts as a moderately potent, reversible, and competitive inhibitor of furin-mediated cleavage of the pentapeptide pGlu-Arg-Thr-Lys-Arg-MCA fluorogenic substrate, with an inhibition constant (Ki) estimated at 1.98 μM [1].

Hexa-D-arginine is an inhibitor of furin,blocks the activation of Pseudomonas aeruginosa exotoxin A in vivo.

Boc-Arg-Val-Arg-Arg-AMC hydrochloride (Boc-RVRR-AMC) is a synthetic fluorogenic substrate efficiently cleaved by the enzyme furin.