You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[(2R,3S,4R,5R)-5-[6-[(2-chloro-3,4-dimethoxyphenyl)methylamino]purin-9-yl]-3,4-dihydroxyoxolan-2-yl]methyl dihydrogen phosphate is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H23ClN5O9P
assistant