LCZ696 Impurity 6 Catalogue L524676 CAS N/A M.W 425.52 M.F C25H31NO5 Specifications FAQs (2R,4S)-4-([1,1'-Biphenyl]-4-ylmethyl)-2-methyl-4-[4-(propan-2-yloxy)-4-oxobutanamido]butanoic acid