You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(1R,5S,6R,7S)-N-[2-(5,6-dimethyl-4-oxo-3H-thieno[2,3-d]pyrimidin-2-yl)ethyl]-3-methyl-4-oxo-10-oxa-3-azatricyclo[5.2.1.01,5]dec-8-ene-6-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H22N4O4S
assistant