LCZ696 Impurity 13 Catalogue L524683 CAS 1038924-97-8 M.W 393.48 M.F C24H27NO4 Specifications FAQs Ethyl (2R,4S)-4-([1,1'-biphenyl]-4-ylmethyl)-2-methyl-4-(2,5-dioxopyrrolidin-1-yl)butanoate