You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(14Z)-14-[dimethylamino(phenyl)methylidene]-4-thia-2,7-diazatricyclo[7.5.0.03,7]tetradeca-1(9),2-dien-6-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H23N3OS
assistant