C[C@@H](CN)CC(=O)O.C[C@@H](CN)CC(=O)O.O=S(=O)(O)c1cccc2c(S(=O)(=O)O)cccc12
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?