Olmesartan medoxomil Related Compound A,1-((2'-(1H-tetrazol-5-yl)-[1,1'-biphenyl]-4-yl)methyl)-4,4-dimethyl-2-propyl-1H-furo[3,4-d]imidazol-6(4H)-one,A cyclic ester impurity of Olmesartan .;Impurity in commercial preparations of Olmesartan,Olmesartan Impurity