O=C(O)c1cccc(NS(=O)(=O)c2ccc(-c3ccc(S(=O)(=O)Nc4cccc(C(=O)O)c4)cc3)cc2)c1
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?