Nintedanib Impurity C Catalogue N225713 CAS 2519501-85-8 M.W 386.4 M.F C23H18N2O4 Specifications FAQs Nintedanib 4-Hydroxyphenyl Analog ; (Z)-Methyl 3-((4-hydroxyphenylamino)(phenyl)methylene)-2-oxoindoline-6-carboxylate