You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
7-(2,3-dihydro-1,4-benzodioxin-6-yl)-2-piperidin-1-ylthieno[2,3-e][1,3]oxazin-4-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H18N2O4S
assistant