You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by methyl 2-[1-[7-methyl-4-oxo-3-[(4-oxo-3-propyl-2-sulfanylidene-1,3-thiazolidin-5-ylidene)methyl]pyrido[1,2-a]pyrimidin-2-yl]-3-oxopiperazin-2-yl]acetate ?
user
C23H25N5O5S2
assistant