You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 2-[4-chloro-5-[ethylphosphanylmethyl(methyl)amino]-2-fluorophenyl]-4,5-dihydroisoindole-1,3-diol .
user
C18H21ClFN2O2P
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