Table 1.

Receptor Affinities and Fluorescence Properties of Final Compounds

				Ki nMa		CHCl3			EtOHb			PBSb,c
comp	X	Y	Z	σ1	σ2	λexc nm	λem nm	Φ	λexc nm	λem nm	Φ	λexc nm	λem nm	εd
1e	CH3	CH2		0.38±0.10	0.68±0.20
7	CH3	A	CH2CH2	2570f	1720±160	450	515	0.17	476	520	0.08	480	535	14391
8	CH3	B	CH2CH2	>5000f	5020±180	346	490	0.32	335	507	0.29	340	510	2600
16	A	CH2	CH2CH2	78.7±18.2	10.8±3.0	451	514	0.20	467	520	0.05	460	520	11300
17	A	CH2	O	96.2f	39.3±11.8	450	512	0.18	465	520	0.04	460	520	6544
18	B	CH2	CH2CH2	9.08±1.32	20.8±1.5	340	490	0.30	335	507	0.20	345	485	4000
19	B	CH2	O	19.8±8.7	25.7±4.7	345	490	0.48	335	507	0.23	343	510	2741
(+)-pentazocine				2.62±0.25
DTG					24.6±2.2

^aValues are the means of n ≥ 2 separate experiments.

^bFluorescence properties herein reported were evaluated on compounds as free bases, but they were also evaluated on their corresponding hydrochloride salts in EtOH and PBS solutions. A maximum of 5 nm shift was observed in the excitation and emission wavelengths when compared to the excitation and emission wavelengths from the corresponding free bases.

^cAll compounds solubilized in PBS gave Φ̣ value very close to 0 and therefore they are not reported.

^dFrom EtOH solutions of compounds in EtOH.

^eFrom Ref 18 where results from binding on human cells, in which compound 1 displays about 40-fold σ₂ versus σ₁ selectivity, are also reported.

^fFrom a unique experiment.