You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named [(1S)-1-hydroxy-1-[hydroxy-[(2R)-2-hydroxy-3-morpholin-4-ylpropoxy]phosphoryl]ethyl]phosphonic acid by IUPAC nomenclature, provide its molecular formula.
user
C9H21NO9P2
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