Abstract In this study, two novel benzimidazole-based N-heterocyclic carbene ligands (1a-b) and their silver(I) complexes (2a-b) were synthesized. All new compounds were characterized by FT-IR, LC-MS, 1H NMR, and 13C NMR spectroscopies. The in vitro antitumor activities of NHC ligands (1a-b) and their silver(I) complexes (2a-b) against DU-145 human prostate cancer cells, MDA-MB-231 and MCF-7 human breast cancer cells and L-929 (normal cells adipose from mouse) were also determined using MTT analysis for 24 h, 48 h, and 72 h. The results showed that while NHC ligands did not have in vitro antitumor activity on MCF-7, MDA-MB-231 and DU-145 cells, Ag(I)-NHC complexes have in vitro antitumor activities. The in vitro antitumor activity of 2a was found to be lower than that of 2b. Ag(I)-NHC complexes were observed to have higher IC50 values for non-cancerous cell lines than cancer cells. Graphical Abstract

中文翻译：

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新型银(I)-N-杂环卡宾配合物的合成及抗肿瘤活性

摘要 本研究合成了两种新型苯并咪唑基 N-杂环卡宾配体 (1a-b) 及其银 (I) 配合物 (2a-b)。所有新化合物均通过 FT-IR、LC-MS、1H NMR 和 13C NMR 光谱进行表征。NHC 配体 (1a-b) 及其银 (I) 复合物 (2a-b) 对 DU-145 人前列腺癌细胞、MDA-MB-231 和 MCF-7 人乳腺癌细胞以及 L-的体外抗肿瘤活性929（来自小鼠的正常细胞脂肪）也使用 MTT 分析测定 24 小时、48 小时和 72 小时。结果表明，虽然 NHC 配体对 MCF-7、MDA-MB-231 和 DU-145 细胞没有体外抗肿瘤活性，但 Ag(I)-NHC 复合物具有体外抗肿瘤活性。发现2a的体外抗肿瘤活性低于2b。观察到 Ag(I)-NHC 复合物对非癌细胞系的 IC50 值高于癌细胞。图形概要