You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name N-(1-bicyclo[1.1.1]pentanyl)-5-oxo-2-(3-phenylazetidin-1-yl)-6,7-dihydrothieno[3,2-d]pyrimidin-4-amine into its molecular formula.
user
C20H22N4OS
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