152551-55-8 Benzyloxycarbonyl-ala-ala-pro-phe-trifluoromethylketone Benzyloxycarbonyl-alanyl-alanyl-prolyl-phenylalanine-trifluoromethylketone Carbobenzoxy-ala-ala-pro-phe-trifluoromethylketone Z-Ala-ala-pro-phe-trifluoromethylketone Zaapf-tfmk