You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named 3-tert-butyl-5-[(5-methyl-[1,2,4]triazolo[4,3-a]quinolin-1-yl)sulfanylmethyl]-1,2,4-oxadiazole by IUPAC nomenclature, provide its molecular formula.
user
C18H19N5OS
assistant