C/C1=N/NC(=S)NCCCN2CCN(CCCNC(=S)N/N=C(/C)C=NNC(=S)NCCCN3CCN(CCCNC(=S)NN=C1)CC3)CC2
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?