You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[(R)-[1-(2-methylbutan-2-yl)tetrazol-5-yl]-thiophen-2-ylmethyl]-3,4-dihydro-1H-isoquinoline is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H25N5S
assistant