You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(3S,5S)-3-ethoxy-9-(1,3,4-thiadiazol-2-yl)-1-oxa-9-azaspiro[4.5]decane is the IUPAC name of a molecule. Please give its molecular formula.
user
C12H19N3O2S
assistant