Synthesis and activity profiles of novel cyclic opioid peptide monomers and dimers
作者:Peter W. Schiller、Thi M. D. Nguyen、Carole Lemieux、Louise A. Maziak
DOI:10.1021/jm00150a005
日期:1985.12
13-membered ring) was shown to be one of the most selective mu-receptor ligands reported to date, whereas the corresponding cyclic dimer, (H-Tyr-D-Orn-Phe-Asp-NH2)2 (1a), was nonselective. The difference in receptor selectivity observed between 1 and 1a is a consequence of the different conformational constraints present in the cyclic monomer and dimer. In contrast to 1, the conformationally less restricted
通过在Orn(或Lys)和Asp(或Glu)残基的侧链氨基和羧基之间形成酰胺键,获得了H-Tyr-D-Xxx-Phe-Yyy-NH2型新的环状阿片肽类似物家族在肽序列的2和4位被取代。肽是完全通过固相技术合成的,除环状单体外,由于位点间反应,在苯甲基胺树脂上的环化反应还会产生侧链连接的反平行环状二聚体。在基于鼠脑膜上对mu和δ阿片类受体选择性放射性标记的置换的结合研究中,高刚性环状单体H-Tyr-D-Orn-Phe-Asp-NH2(1)(含13元环)被证明是迄今为止报道的最具选择性的mu受体配体之一,而相应的环状二聚体,(H-Tyr-D-Orn-Phe-Asp-NH2)2(1a)是非选择性的。在1a和1a之间观察到的受体选择性差异是环状单体和二聚体中存在的不同构象约束的结果。与1相反,构象上受限制较少的环状类似物H-Tyr-D-Lys-Phe-Glu-NH2(3)(15元环)没有受体偏爱。