You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Name the molecular formula for the molecule established as methyl (3R)-5-[(3aR,9bS)-3,3a,4,9b-tetrahydrochromeno[4,3-c][1,2]oxazol-1-yl]-5-oxo-3-(1,3,5-triazin-2-yl)pentanoate using the IUPAC nomenclature.
user
C19H20N4O5
assistant