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 [(4R)-5-ethoxycarbonyl-2-oxo-4-phenyl-3,4-dihydro-1H-pyrimidin-6-yl]methyl 3,5-dimethyl-1,2-oxazole-4-carboxylate ?
user
C20H21N3O6
assistant