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What is the molecular formula of the molecule identified by 5-[2-[(5-ethyl-1,3,4-thiadiazol-2-yl)amino]-2-oxoethyl]-N,N-dimethyl-6-oxo-7,8,9,10-tetrahydro-6aH-pyrido[1,2-a]quinoxaline-3-carboxamide ?
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C21H26N6O3S
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