Reddy Eda Rami, Trivedi Rajiv, Sarma Akella Venkata Subrahmanya, Sridhar Balasubramanian, Anantaraju Hasitha Shilpa, Sriram Dharmarajan, Yogeeswari Perumal, Nagesh Narayana
Inorganic and Physical Chemistry Division, CSIR-IICT, Hyderabad-500007, India.
Dalton Trans. 2015 Oct 28;44(40):17600-16. doi: 10.1039/c5dt03266k. Epub 2015 Sep 22.
A series of five palladium(ii) pyridyl-imine Schiff base complexes 5a-e containing boronate esters with protected sugar diols derived from d-xylose, l-sorbose and d-mannitol were designed and synthesized starting from pyridyl-imines generated in situ from 3-aminophenyl boronate ester of sugars 3a-e and 2-pyridinecarboxaldehyde, followed by the addition of Pd(cod)Cl2 in dichloromethane solvent. All the complexes are remarkably stable orange/yellow crystalline solids and were obtained in good yields. The complexes were fully characterized by FT-IR, multinuclear NMR ((1)H, (13)C and (11)B), UV-visible spectroscopy, and elemental analysis. The solid state structures of 3a and 5a were established by single crystal X-ray diffraction analysis. The complexes have been tested for their in vitro anticancer activities against human colon cancer (HT-29) and breast cancer (MDA-MB-231) cell lines. All the complexes have shown moderate to good cytotoxicity in both the cancer cell lines with IC50 values ranging from 4.27 to 34.76 μM. Strikingly, 5a displayed selective anticancer activity against both HT-29 and MDA-MB-231 cells with low IC50 values 6.71 and 8.58 μM respectively. Results also demonstrate that some of these complexes are highly potent against HT-29 cells as compared to the other cancer cell lines. In particular, 1,2:5,6-di-O-isopropylidene-d-mannitol complex 5d showed a two-fold higher toxicity against HT-29 cells in comparison with that of cisplatin. In addition, these complexes are less toxic to model non-tumorigenic human embryonic kidney cells (HEK-293T). Furthermore, the interaction of the complexes with calf thymus DNA (CT-DNA) was investigated using spectroscopy and viscosity measurements. It was found that they intercalate with DNA.
设计并合成了一系列五种含硼酸酯的钯（II）吡啶基-亚胺席夫碱配合物5a-e，其硼酸酯与由d-木糖、l-山梨糖和d-甘露醇衍生的受保护糖二醇相连。合成过程是从糖3a-e的3-氨基苯基硼酸酯与2-吡啶甲醛原位生成的吡啶基-亚胺开始，然后在二氯甲烷溶剂中加入Pd（cod）Cl2。所有配合物均为非常稳定的橙/黄色结晶固体，产率良好。通过傅里叶变换红外光谱（FT-IR）、多核核磁共振（（1）H、（13）C和（11）B）、紫外-可见光谱和元素分析对配合物进行了全面表征。通过单晶X射线衍射分析确定了3a和5a的固态结构。测试了这些配合物对人结肠癌细胞（HT-29）和乳腺癌细胞（MDA-MB-231）的体外抗癌活性。所有配合物在两种癌细胞系中均表现出中度至良好的细胞毒性，IC50值范围为4.27至34.76μM。引人注目的是，5a对HT-29和MDA-MB-231细胞均表现出选择性抗癌活性，IC50值分别低至6.71和8.58μM。结果还表明，与其他癌细胞系相比，其中一些配合物对HT-29细胞具有高效活性。特别是，1,2:5,6-二-O-异亚丙基-d-甘露醇配合物5d对HT-29细胞的毒性比顺铂高两倍。此外，这些配合物对模型非致瘤性人胚肾细胞（HEK-293T）的毒性较小。此外，使用光谱学和粘度测量研究了配合物与小牛胸腺DNA（CT-DNA）的相互作用。发现它们可插入DNA。
