You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[1-[2-[(2R,6S)-2,6-dimethylmorpholin-4-yl]-2-oxoethyl]indol-3-yl]sulfanyl-N-propylacetamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H29N3O3S
assistant