You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule (2R,7R)-7-ethyl-2-(2-methoxyphenyl)-2,3,5,6,7,8-hexahydro-1H-[1]benzothiolo[2,3-d]pyrimidin-4-one ?
user
C19H22N2O2S
assistant