You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[3-[(4aS,7aS)-3-amino-1,1-dihydroxy-2,2-dimethyl-7,7a-dihydro-5H-furo[3,4-b][1,4]thiazin-4a-yl]-4-fluorophenyl]-5-methoxy-3-methylpyridine-2-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C22H27FN4O5S
assistant