You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 3-O-(2-methylsulfanylethyl) 5-O-[2-(pyridine-3-carbonylamino)ethyl] 2,6-dimethyl-4-(3-nitrophenyl)-3,4-dihydropyridine-3,5-dicarboxylate by IUPAC nomenclature, provide its molecular formula.
user
C26H28N4O7S
assistant