Molecular probes that target specific markers expressed in solid tumours are in demand for cancer imaging and radionuclide therapy applications. The synthesis, characterization, and in vivo evaluation of radioiodinated triazoles designed as probes to target melanoma are described here. Compounds were prepared using a thermal click reaction between ethynylstannane and methyl 2-azidoacetate, resulting in preferential formation of the corresponding 1,4-tin triazole. The primary amine of various targeting vectors was then coupled to the resulting tin triazole methyl ester. These precursors were labelled with no carrier added 123I or 125I and purified by high performance liquid chromatography to give isolated radiochemical yields between 6% and 51% and radiochemical purities of >95% in all cases. Among the evaluated compounds, N-(2-diethylamino-ethyl)-2-(4-iodo-[1,2,3]triazol-1-yl)acetamide (7a) and N-(1-benzylpiperidin-4-yl)-2-(4-iodo-1H-1,2,3-triazol-1-yl)acetamide (7d) showed the most promising in vivo data, and their 123I-labelled forms were used in single photon emission computed tomography computed tomography (SPECT–CT) imaging studies. The imaging data showed excellent tumour visualization with a very high signal to noise ratio.
靶向固体肿瘤中特定标记物的分子探针在癌症成像和放射性核素治疗应用中需求旺盛。本文描述了设计为靶向黑色素瘤的三唑类探针的合成、表征和体内评估的放射碘化合物。化合物是通过乙炔基锡烷和甲基2-叠氮乙酸酯之间的热点击反应制备的,导致了相应的1,4-锡三唑的优先形成。然后,各种靶向载体的主氨基与得到的锡三唑甲酯偶联。这些前体物质被标记为无载体添加的123I或125I,并通过高效液相色谱纯化,得到的分离放射化学产率在6%至51%之间,所有情况下的放射化学纯度均高于95%。在评估的化合物中,N-(2-二乙氨乙基)-2-(4-碘-[1,2,3]三唑-1-基)乙酰胺(7a)和N-(1-苄哌啶-4-基)-2-(4-碘-1H-1,2,3-三唑-1-基)乙酰胺(7d)展现出最有希望的体内数据,它们的123I标记形式被用于单光子发射计算机断层扫描(SPECT-CT)成像研究。成像数据显示出优秀的肿瘤可视化效果,信噪比非常高。