COc1cc([C@@H]2OC(=O)C3C2C(=O)O[C@H]3c2cc(OC)c(OC)c(OC)c2)cc(OC)c1OC
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?