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system
What is the molecular formula of the molecule identified by (8aR)-2-[(4-methoxyphenyl)methyl]-7-[(6-methoxypyridin-3-yl)methyl]-5,6,8,8a-tetrahydro-1H-imidazo[1,5-a]pyrazin-3-one ?
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C21H26N4O3
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