Gefitinib 3-Deschloro 3,4-Difluoro Impurity Catalogue G420566 CAS 184475-50-1 M.W 430.45 M.F C22H24F2N4O3 Specifications FAQs N-(3,4-Difluorophenyl)-7-methoxy-6-(3-morpholinopropoxy)quinazolin-4-amine