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What is the molecular formula of the molecule identified by 1-cyclopropyl-6-hydroxy-5-[(1R)-6-methoxy-2,3,4,9-tetrahydro-1H-pyrido[3,4-b]indol-2-ium-1-yl]-2-sulfanylidenepyrimidin-4-one ?
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C19H21N4O3S+
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