You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
prop-2-ynyl 3-[(3aS,4R,6R,6aR)-4-[(4R)-2,2-dimethyl-1,3-dioxolan-4-yl]-2,2-dimethyl-3a,4,6,6a-tetrahydrofuro[3,4-d][1,3]dioxol-6-yl]propanoate is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H26O7
assistant