You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Under IUPAC nomenclature, a molecule named (7R)-9-(4-chlorophenyl)-1,7-dimethyl-3-propyl-6,7,8,10-tetrahydropurino[7,8-a]pyrimidin-5-ium-2,4-dione is given. What is its corresponding molecular formula?
user
C19H23ClN5O2+
assistant