You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance (7-hydroxy-1,5,8-trimethylidene-2-oxo-3a,4,5a,6,7,8a,9,9a-octahydroazuleno[6,5-b]furan-9-yl) 2-(hydroxymethyl)prop-2-enoate .
user
C19H22O6
assistant