Archer S, Medzihradsky F, Seyed-Mozaffari A, Emmerson P J
Department of Chemistry, Cogswell Laboratory, Rensselaer Polytechnic Institute, Troy, NY 12181.
Biochem Pharmacol. 1992 Jan 22;43(2):301-6. doi: 10.1016/0006-2952(92)90292-q.
Alkylation of sarcosine with 4-chloro-nitrobenzo-2-oxa-1,3-diazole (NBD-chloride) furnished a fluorescent tag that was coupled with a tetrahydrothebaine derivative and beta-naltrexamine, respectively, to yield the fluorescent opioids 7 alpha-(1R)-1-hydroxy-1-methyl-3-(4-hydroxyphenyl)-propyl]-6,14- endoethenotetrahydrothebaine NBD-sarcosinate (ASM-5-10) and N-cyclopropylmethyl-3-hydroxy-14 beta-hydroxy-6 beta-(NBD sarcosinyl)-amino-epoxymorphinan (ASM-5-67). The fluorescence intensity of the novel opioids allowed their detection at subnanomolar concentrations, and was dependent on the polarity of the solvent. Maximum quantum yield was obtained in ethyl acetate and ethanol, and minimal fluorescence in heptane and water. Compounds ASM-5-10 and ASM-5-67 displaced the opioid receptor binding of [3H]Tyr-D-Ala-Gly-(Me)Phe-Gly-ol in monkey brain membranes with IC50 values of 8.4 and 1.5 nM, respectively. Whereas ASM-5-67 bound to mu, delta, and kappa receptors with comparable affinities, ASM-5-10 was mu-selective, with selectivity indices (ratio of respective IC50 values) of 0.04 for both mu/delta and mu/kappa. The sodium response ratio in binding revealed a pronounced agonist property of ASM-5-10. Both opioids were lipophilic, with octanol-water partition coefficients (log Papp) of 2.8 (ASM-5-10) and 1.0 (ASM-5-67). ASM-5-10 exhibited particularly strong membrane retention that was not reversible by four washes. Their favorable characteristics in fluorescence, receptor binding, and membrane interaction make these newly developed ligands useful molecular probes to study opioid receptor mechanisms.
将肌氨酸与4-氯-硝基苯并-2-恶唑-1,3-二氮杂茂（NBD-氯化物）进行烷基化反应，得到一种荧光标记物，该标记物分别与四氢蒂巴因衍生物和β-纳曲胺偶联，生成荧光阿片类药物7α-(1R)-1-羟基-1-甲基-3-(4-羟基苯基)-丙基]-6,14-内乙烯基四氢蒂巴因NBD-肌氨酸盐（ASM-5-10）和N-环丙基甲基-3-羟基-14β-羟基-6β-(NBD-肌氨酰基)-氨基-环氧吗啡喃（ASM-5-67）。新型阿片类药物的荧光强度使其能够在亚纳摩尔浓度下被检测到，并且取决于溶剂的极性。在乙酸乙酯和乙醇中获得最大量子产率，而在庚烷和水中荧光最小。化合物ASM-5-10和ASM-5-67在猴脑膜中取代[3H]酪氨酸-D-丙氨酸-甘氨酸-(甲基)苯丙氨酸-甘醇的阿片受体结合，IC50值分别为8.4和1.5 nM。虽然ASM-5-67以相当的亲和力与μ、δ和κ受体结合，但ASM-5-10是μ选择性的，μ/δ和μ/κ的选择性指数（各自IC50值的比值）均为0.04。结合中的钠反应比显示ASM-5-10具有明显的激动剂特性。两种阿片类药物都具有亲脂性，辛醇-水分配系数（log Papp）分别为2.8（ASM-5-10）和1.0（ASM-5-67）。ASM-5-10表现出特别强的膜保留能力，四次洗涤后仍不可逆。它们在荧光、受体结合和膜相互作用方面的良好特性使这些新开发的配体成为研究阿片受体机制的有用分子探针。
