You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Under IUPAC nomenclature, a molecule named sodium;1-(6-bromopyrrolo[2,1-f][1,2,4]triazin-4-yl)azetidine-3-carboxylic acid;methyl 1-(6-bromopyrrolo[2,1-f][1,2,4]triazin-4-yl)azetidine-3-carboxylate;hydroxide is given. What is its corresponding molecular formula?
user
C21H21Br2N8NaO5
assistant