Table 4: Functional bioactivities of opioid ligands 51–70.

GPIMVD

Nos.CompoundsIC50 (nM)apA2bIC50 (nM)pA2Reference

51Dmt-NH-(CH2)2-NH-Dmt2,844c>10,0005.5[18]
52Dmt-NH-(CH2)4-NH-Dmt5.33>10,0005.8[18]
53Dmt-NH-(CH2)6-NH-Dmt3.08>10,0006.1[18]
54Dmt-NH-(CH2)8-NH-Dmt53.7>10,0006.4[18]
553,6-bis[Dmt-NH-CH2]-5-methyl-2(1H)-pyrazinone1,695>10,0006.47[19]
563,6-bis[Dmt-NH(CH2)2]-5-methyl-2(1H)-pyrazinone12.9>10,0006.56[19]
573,6-bis[Dmt-NH(CH2)3]-5-methyl-2(1H)-pyrazinone1.33>10,000NDd[19]
583,6-bis[Dmt-NH(CH2)4]-5-methyl-2(1H)-pyrazinone1.941.5ND[19]
593,6-bis[Dmt-Tic-NH-CH2]-5-methyl-2(1H)-pyrazinone>10,000ND>10,00011.22[20]
603,6-bis[Dmt-Tic-NH(CH2)2]-5-methyl-2(1H)-pyrazinone>10,0006.78>10,00010.73[20]
613,6-bis[Dmt-Tic-NH(CH2)3]-5-methyl-2(1H)-pyrazinone7,025ND>10,00010.56[20]
623,6-bis[Dmt-Tic-NH(CH2)4]-5-methyl-2(1H)-pyrazinone>10,000ND>10,00011.06[20]
633-[Dmt-Tic-NH(CH2)3]-6-[Dmt-Tic-NH(CH2)4]-5-methyl-2(1H)-pyrazinone>10,000ND>10,00010.6[20]
643-[Dmt-Tic-NH(CH2)4]-6-[Dmt-Tic-NH(CH2)3]-5-methyl-2(1H)-pyrazinone>10,0006.95>10,00010.47[20]
653-[Dmt-Tic-NH(CH2)2]-6-[Dmt-Tic-NH(CH2)4]-5-methyl-2(1H)-pyrazinone>10,000ND>10,00010.99[20]
66bis[Dmt-Tic-NH]butane>10,0006.99>10,00010.51[20]
67bis[Dmt-Tic-NH]hexane2,715ND>10,00010.62[20]
68bis[Dmt-Tic-NH]decane5,425ND>10,00010.97[20]
69bis[N,N-dimethyl-Dmt-Tic-NH]hexane>10,0008.34>10,00011.28[20]
703,6-bis[N,N-dimethyl-Dmt-Tic-NH-propyl]-5-methyl-2(1H)-pyrazinone>10,0007.71>10,00010.42[20]

aIC50 value is the concentration required to 50% inhibition of the electrically induced contraction in a muscle. bpA2 is the negative log of the molar concentration required to double the agonist IC50 value in order to achieve the original response. cNot tested. dNot determined.