SUC-ALA-ALA-VAL-PNA

N-SUCCINYL-ALA-ALA-VAL P-NITROANILIDE

N-succinyl-alanine-alanine-valine-p-nitroanilide

3-carboxypropionyl-alanyl-alanyl-valine-4-nitroanilide

N-(3-Carboxy-1-oxopropyl)-L-Ala-L-Ala-N-(4-nitrophenyl)-L-Val-NH2

N-(3-carboxy-1-oxopropyl)-L-alanyl-L-alanyl-N-(4-nitrophenyl)-L-valinamide