O=C1C([N-]S(=O)(=O)c2cccs2)=C([n+]2ccc(CCCc3ccccc3)cc2)C(=O)c2ccccc21
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?