You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance 8,10,10-trimethyl-10a-[(E)-2-(3-nitrophenyl)ethenyl]-3,4-dihydro-1H-pyrimido[1,2-a]indol-2-one .
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C22H23N3O3
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