You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-[1-[(2-chloro-4-morpholin-4-ylthieno[3,2-d]pyrimidin-6-yl)methyl]piperidin-4-yl]-4-methoxybutan-1-amine into its molecular formula.
user
C21H32ClN5O2S
assistant