Azilsartan Impurity U Catalogue A195641 CAS 1993494-84-0 M.W 369.38 M.F C22H15N3O3 Specifications FAQs 3-((2'-cyano-[1,1'-biphenyl]-4-yl)methyl)-2-oxo-2,3-dihydro-1H- benzo[d]imidazole-4-carboxylic acid