You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance ethyl 4-[6-[(2-methyl-3,4-dihydro-1H-isoquinolin-7-yl)amino]pyrazolo[3,4-d]pyrimidin-1-yl]butanoate .
user
C21H26N6O2
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