C=C(CO)[C@H]1Cc2c(ccc3c2O[C@H]2COc4cc(OC)c(OC)cc4[C@@H]2C3=O)O1
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?