You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance 3-[(2S,4R)-5-[diethoxy(oxido)phosphaniumyl]-2-ethoxy-6-ethylsulfanyl-3,4-dihydro-2H-thiopyran-4-yl]pyridine .
user
C18H28NO4PS2
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