(S,E)-4-Bromo-N-(4-((3-chloro-4-fluorophenyl)amino)-7-((tetrahydrofuran-3-yl)oxy)quinazolin-6-yl)but-2-enamide (Afatinib Impurity)

(S,E)-4-Bromo-N-(4-((3-chloro-4-fluorophenyl)amino)-7-((tetrahydrofuran-3-yl)oxy)quinazolin-6-yl)but-2-enamide (Afatinib Impurity)