Azilsartan Impurity B Catalogue A195622 CAS 1696392-11-6 M.W 415.45 M.F C24H21N3O4 Specifications FAQs 1-((2'-carbamoyl-[1,1'-biphenyl]-4-yl)methyl)-2-ethoxy-1H-benzo[d]imidazole-7-carboxylic acid