You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule identified by 5-amino-3-[(1R,6R,9R,10R,15R,18R)-8-(6-aminopurin-9-yl)-9-fluoro-3,12-dihydroxy-18-methoxy-3-oxo-12-sulfanylidene-2,4,7,11,13,16-hexaoxa-3lambda5,12lambda5-diphosphatricyclo[13.2.1.06,10]octadecan-17-yl]-6H-[1,2]thiazolo[4,3-d]pyrimidin-7-one ?
user
C21H24FN9O11P2S2
assistant