C=CC(=O)N1CCN(Cc2cccc3c(CCNC(=O)c4ccc[nH]4)c[nH]c23)CC1
C=CC(=O)N1CC(NCc2cccc3c(CCNC(=O)c4ccc[nH]4)c[nH]c23)C1
C=CC(=O)NC1CN(Cc2cccc3c(CCNC(=O)c4ccc[nH]4)c[nH]c23)C1
C=CC(=O)N1C[C@@H]2CN(Cc3cccc4c(CCNC(=O)c5ccc[nH]5)c[nH]c34)C[C@@H]2C1
C=CC(=O)N1CCN(Cc2cccc3c(CCNC(C)=O)c[nH]c23)CC1
C=CC(=O)N1CCN(Cc2cccc3c(CCNC(=O)[C@@H]4CCCN4)c[nH]c23)CC1
C=CC(=O)N1CCN(Cc2cccc3c(CCNS(C)(=O)=O)c[nH]c23)CC1
C=CC(=O)N1CCN(Cc2cccc3c(CCNC(=O)CCCN(C)C)c[nH]c23)CC1
C=CC(=O)N1CCN(Cc2cccc3c(CC(N)=O)c[nH]c23)CC1
C=CC(=O)N1CC(NCc2cccc3c(CC(N)=O)c[nH]c23)C1
Based on melatonin analogue X0104, and the covalent fragment x0692. All proposed analogues can be synthesized in ~3-4 easy steps from commercially avaialable Indole-7-carboxaldehyde. Pyrrole amide makes extra hydrogen bond with Glu166 C=O Fluor on indole ommited to simplify synthesis. Corresponding N-methylindoles could be good alternatives regarding stability.