You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule [(2R,3S,4R,5R)-5-(6-aminopurin-9-yl)-5-(2-cyanoethyl)-3,4-dihydroxyoxolan-2-yl]methoxyphosphonamidous acid ?
user
C13H18N7O5P
assistant