You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
methyl (1R,9R,10R,12R,19S)-20-methyl-8,16-diazahexacyclo[10.6.1.19,12.01,9.02,7.016,19]icosa-2,4,6,13-tetraene-10-carboxylate;dihydrochloride is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H26Cl2N2O2
assistant