O=C(O)c1cc(O)c2c(c1)C([C@@H]1c3cccc(O)c3C(=O)c3c(O)cc(C(=O)O)cc31)c1cccc(O)c1C2=O
The donor in a hydrogen bond is usually a strongly electronegative atom such as N, O, or F that is covalently bonded to a hydrogen bond. How many hydrogen bond donors does the molecule have?