You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named ethyl 2-[[6-hydroxy-3-phenyl-7-(1,3-thiazol-2-yl)quinoxaline-5-carbonyl]amino]acetate by IUPAC nomenclature, provide its molecular formula.
user
C22H18N4O4S
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