You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[(3S,3aR,6S,6aR)-6-hydroxy-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan-3-yl]-2-methoxypyridine-4-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C13H16N2O5
assistant