N2-[[(1-Carboxy-2-phenylethyl)amino]carbonyl]-L-arginyl-N-[4-[(aminoiminomethyl)amino]-1-formylbutyl]-L-valinamide PHE-ARG-VAL-ARG-CHO Antipain research grade 4-((aminoiminomethyl)amino)-1-formylbutyl)- ANTIPAIN HYDROCHLORIDE DIHYDRATE N2-[[(1-carboxyphenethyl)amino]carbonyl]-L-arginyl-N-[4-[(aminoiminomethyl)amino]-1-formylbutyl]-L-valinamide ANTIPAIN ~10000 U/MG Nα-[N2-[[(1-Carboxy-2-phenylethyl)amino]carbonyl]-L-arginyl]-N-[4-[(aminoiminomethyl)amino]-1-formylbutyl]-L-valinamide