CCOC(=O)C(C(=O)OCC)[C@@H]1CS(=O)(=O)C[C@H]1C(C(=O)OCC)C(=O)OCC
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?