Three hexacoordinated octahedral nickel (II) complexes, [Ni (Trp-sal) (phen) (CH₃OH)] (1), [Ni (Trp-o-van) (phen) (CH₃OH)]•2CH₃OH (2), and [Ni (Trp-naph) (phen) (CH₃OH)] (3) (where Trp-sal = Schiff base derived from tryptophan and salicylaldehyde, Trp-o-van = Schiff base derived from tryptophan and o-vanillin, Trp-naph = Schiff base derived from tryptophan and 2-hydroxy-1-naphthaldehyde, phen = 1, 10-phenanthroline), have been synthesized and characterized as potential anticancer agents. Details of structural study of these complexes using single-crystal X-ray crystallography showed that distorted octahedral environment around nickel (II) ion has been satisfied by three nitrogen atoms and three oxygen atoms. All these complexes displayed moderate cytotoxicity toward esophageal cancer cell line Eca-109 with the IC₅₀ values of 23.95 ± 2.54 μM for 1, 18.14 ± 2.39 μM for 2, and 21.89 ± 3.19 μM for 3. Antitumor mechanism studies showed that complex 2 can increase the autophagy, reactive oxygen species (ROS) levels, and decrease the mitochondrial membrane potential remarkably in a dose-dependent manner in the Eca-109 cells. Complex 2 can cause cell cycle arrest in the G2/M phase. Additionally, complex 2 can regulate the Bcl-2 family and autophagy-related proteins.

中文翻译：

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氨基酸希夫碱镍 (II) 配合物作为潜在抗癌药物的体外合成


三个六配位八面体镍 (II) 配合物，[Ni (Trp-sal) (phen) (CH ₃ OH)] (1)，[Ni (Trp- o -van) (phen) (CH ₃ OH)]•2CH ₃ OH (2) 和 [Ni (Trp-naph) (phen) (CH ₃ OH)] (3)（其中 Trp-sal = 源自色氨酸和水杨醛的席夫碱，Trp- o -van = 源自色氨酸的席夫碱邻香草醛（Trp-naph = 源自色氨酸和 2-羟基-1-萘醛的席夫碱，phen = 1, 10-菲咯啉）已被合成并表征为潜在的抗癌剂。使用单晶 X 射线晶体学对这些配合物的结构研究的细节表明，镍 (II) 离子周围的扭曲八面体环境已由三个氮原子和三个氧原子满足。所有这些复合物均对食管癌细胞系 Eca-109 表现出中等的细胞毒性，1 的 IC ₅₀值为 23.95 ± 2.54 μM ，2 的 IC 50 值为 18.14 ± 2.39 μM ，3 的 IC 50 值为 21.89 ± 3.19 μM 。抗肿瘤机制研究表明在 Eca-109 细胞中，复合物 2 可以以剂量依赖性方式显着增加自噬、活性氧 (ROS) 水平并降低线粒体膜电位。复合物 2 可以导致细胞周期停滞在 G2/M 期。此外，复合物 2 可以调节 Bcl-2 家族和自噬相关蛋白。