You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 7-[1-[(2Z)-2-(2,3,4,6-tetrahydro-1H-phosphinino[3,4-b]pyrazin-7-ylidene)oxan-3-yl]but-2-enyl]-3,4-dihydro-2H-thieno[3,4-b][1,4]oxazine into its molecular formula.
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C22H28N3O2PS
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