You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[9-[(2R,4S,5S)-5-ethyl-5-ethynyl-4-hydroxyoxolan-2-yl]-2-fluoropurin-6-yl]dodecanamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C25H36FN5O3
assistant