You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Under IUPAC nomenclature, a molecule named (3R)-3-acetamido-N-[(4R)-3,4-dihydro-2H-chromen-4-yl]-3-phenylpropanamide is given. What is its corresponding molecular formula?
user
C20H22N2O3
assistant