Boc-Leu-Gly-Arg-AMC is a specific fluorogenic substrate designed for the enzymatic detection and quantification of complement component C3/C5 convertases, coagulation factor Xa, and soybean trypsin-like enzyme activity. Boc-Leu-Gly-Arg-AMC is also susceptible to hydrolysis by macropain, a high molecular weight thiol proteinase isolated from human erythrocytes, making it a versatile tool for enzymatic assays.

To demonstrate the presence of proteolytic enzymes capable of producing sodifrin in the abdominal gland, polybutoxycarbo-nyl (Boc)-Leu-Gly-Arg-4-methylcoumaryl-7-amide (MCA) and Boc-Leu-Leu-Lys-MCA were used as synthetic substrates. Crude extracts of the abdominal gland hydrolyzed both substrates to release 7-amino-4-methylcoumarin, indicating the presence of enzymes in the gland that generate sodifrin from its precursor molecule. The activity of the extracts to cleave Boc-Leu-Gly-Arg-AMC was optimal at pH 9.0 and 45°C, while the activity to cleave Boc-Leu-Leu-Lys-MCA was optimal at pH 9.0 and 40°C. [1]