You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (3aR,4S,5S,7S,7aS)-5-diethoxyphosphoryl-4-(difluoromethyl)-2,2-dimethyl-7-phenylmethoxy-3a,4,5,6,7,7a-hexahydro-1,3-benzodioxole by IUPAC nomenclature, provide its molecular formula.
user
C21H31F2O6P
assistant