COc1c(CC=C(C)C)c2c(c3oc(=O)c(-c4ccc(O)cc4)c(O)c13)C=CC(C)(C)O2
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?