You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 1-methyl-N-[[(5R,7S)-2-methylsulfonyl-6-oxa-2-azaspiro[4.5]decan-7-yl]methyl]pyrrole-2-carboxamide by IUPAC nomenclature, provide its molecular formula.
user
C16H25N3O4S
assistant