You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-(2-ethylphenyl)-2-(7-thia-9,11-diazatricyclo[6.4.0.02,6]dodeca-1(12),2(6),8,10-tetraen-12-ylamino)acetamide into molecular formula.
user
C19H20N4OS
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