Fexofenadine EP Impurity-G

2-[4-[(1RS)-4-[4-(Diphenylmethylidene)piperidin-1-yl]-1-hydroxybutyl]phenyl]-2-methylpropanoic Acid; Fexofenadine olefin; 2-(4-{4-[4-(Diphenylmethylene)piperidin-1-yl]-1-hydroxybutyl}phenyl)-2-methylpropanoic acid ; 4-[4-[4-(Diphenylmethylene)-1-piperidinyl]-1-hydroxybutyl]-α,α-dimethyl-benzeneacetic Acid