N-BOC-L-ALA-ALA-PRO-ALA-P-NITROANILIDE Boc-AAPA-pNA BOC-ALA-ALA-PRO-ALA-PNA BOC-ALA-ALA-PRO-ALA-P-NITROANILIDE ELASTASE SUBSTRATE II, COLORIMETRIC Boc-Ala-Ala-Pro-Ala-p-Nitroaniline L-Alaninamide,N-[(1,1-dimethylethoxy)carbonyl]-L-alanyl-L-alanyl-L-prolyl-N-(4-nitrophenyl)- L-Alaninamide, N-[(1,1-dimethylethoxy)carbonyl]-L-alanyl-L-alanyl-L-prolyl-N-(4-nitrophenyl)- (9CI)