You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
For the molecule named (5R,5aR,8aR,9S)-9-hydroxy-5,7,7-trimethyl-1,5,5a,6,8,8a,9,9a-octahydroazuleno[5,6-c]furan-3-one by IUPAC nomenclature, provide its molecular formula.
user
C15H22O3
assistant