You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 2-[1-[2-(4-chloroanilino)-2-oxoethyl]-5-oxo-1,2,4-triazol-4-yl]-4-methyl-N-(pyridin-3-ylmethyl)-1,3-thiazole-5-carboxamide .
user
C21H18ClN7O3S
assistant