O=C(COC(=O)/C=C/C(=O)OCC(=O)NC12CC3CC(CC(C3)C1)C2)NC12CC3CC(CC(C3)C1)C2
Hydrogen bond acceptor: The atom, ion, or molecule component of a hydrogen bond which does not supply the bridging (shared) hydrogen atom. How many hydrogen bond acceptors does the molecule have?