CCOC(=O)NC(=O)c1cn(CC(=O)NCC(=O)NCC(=O)N2CCN(CCn3c(C)nc(C(N)=O)c3N)CC2)c(=O)[nH]c1=O
The electronegative atoms usually involved in hydrogen bonding are oxygen, nitrogen and fluorine. How many hydrogen bond acceptors does the molecule contain?