You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[[(1R,3R,4R,11S)-3-(6-aminopurin-9-yl)-4,8,11-trihydroxy-6,9,13-trioxo-2,5,10,12-tetraoxatricyclo[6.3.3.04,11]tetradecan-1-yl]methoxy-hydroxyphosphoryl] [(2R,3S,4R,5R)-5-(3-carbamoyl-4H-pyridin-1-yl)-3,4-dihydroxyoxolan-2-yl]methyl hydrogen phosphate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C27H31N7O21P2
assistant