87768-72-7 A 19009 A-19009 AIDS-166548 AIDS166548 Antibiotic A 19009 L-Alanine, N-L-alanyl-3-((4-amino-1,4-dioxo-2-butenyl)amino)-, (E)- N-(N(3)-Fumaramoyl-2,3-diaminopropanoyl)alanine