You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl (5R)-3-[2-[[(2S)-butan-2-yl]amino]-2-oxoethyl]-5-(4-chlorophenyl)-7-phenyl-5H-[1,3]thiazolo[3,2-a]pyrimidine-6-carboxylate is the IUPAC name of a molecule. Please give its molecular formula.
user
C27H28ClN3O3S
assistant