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What is the molecular formula of the compound with this IUPAC name [1-[(2R,4S,5S)-5-(2-ethynyl-5-methyl-6-oxo-1H-pyrazin-3-yl)-3-hydroxy-4-methoxyoxolan-2-yl]-2-methylbutan-2-yl]oxy-(2-hydroxybutan-2-yl)phosphinic acid ?
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C21H33N2O8P
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