COC(=O)C1=C(O)C(C(=O)OC)[C@@]2(O)[C@@H](C(=O)OC)CC[C@@H]1[C@@H]2C(=O)OC
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?