You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule methyl (6S)-3-benzyl-5-(4-fluorophenyl)sulfonyl-6,7-dihydro-4H-imidazo[4,5-c]pyridine-6-carboxylate .
user
C21H20FN3O4S
assistant