You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (1R)-N-[[(3R)-1,4-dioxaspiro[4.6]undecan-3-yl]methyl]-1-(1H-imidazol-2-yl)-1-thiophen-2-ylmethanamine by IUPAC nomenclature, provide its molecular formula.
user
C18H25N3O2S
assistant