You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(6R)-6-(2,3-dimethoxyphenyl)-3-methylsulfanyl-2,6-dihydro-[1,2,4]triazino[1,6-c]quinazolin-1-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C19H18N4O3S
assistant