CCOC(=O)O[C@@H](C)OC(=O)[C@@H]1N2C(=O)[C@@H](NC(=O)[C@@H](N)c3ccccc3)[C@H]2SC1(C)C
Hydrogen bond acceptor is the chemical compound which contains the lone electron pairs that participate in the hydrogen bond formation. How many hydrogen bond acceptors does the molecule contain?