You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule 6-(3-methoxypropyl)-4,7,8-trimethyl-2-(2-methylprop-2-enyl)purino[7,8-a]imidazole-1,3-dione ?
user
C18H25N5O3
assistant