CC(=O)Oc1cc(C)c(OC(C)=O)c2c1[C@H]1CC[C@]3(C)[C@@H](OC(C)=O)CC[C@H]3[C@@H]1CC2
Hydrogen bond acceptor is the chemical compound which contains the lone electron pairs that participate in the hydrogen bond formation. How many hydrogen bond acceptors does the molecule contain?