Highly photocytotoxic 1,4-dipegylated zinc(ii) phthalocyanines. Effects of the chain length on the in vitro photodynamic activities
作者:Jian-Yong Liu、Xiong-Jie Jiang、Wing-Ping Fong、Dennis K. P. Ng
DOI:10.1039/b814627f
日期:——
A new series of 1,4-dipegylated zinc(II) phthalocyanines have been synthesised and spectroscopically characterised. The derivatives ZnPc[O(CH2CH2O)nMe]2 (n = 2, 4, ca. 12) have been prepared by mixed cyclisation of the corresponding disubstituted phthalonitriles with an excess of unsubstituted phthalonitrile in the presence of Zn(OAc)2·2H2O and 1,8-diazabicyclo[5.4.0]undec-7-ene. The other two analogues ZnPc[O(CH2CH2O)nMe]2 (n = 6, 8) have been prepared by chain elongation reaction of ZnPc[O(CH2CH2O)4H]2. These macrocycles are highly soluble and remain non-aggregated in DMF as shown by the sharp Q-band absorption. Compared with the unsubstituted zinc(II) phthalocyanine, these di-α-substituted analogues have a red-shifted Q band (at 689 vs. 670 nm) and exhibit a relatively weaker fluorescence emission and a higher efficiency at generating singlet oxygen. Upon illumination, these compounds are highly cytotoxic toward HT29 human colorectal carcinoma and HepG2 human hepatocarcinoma cells. The compounds with medium-length substituents are particularly potent, having IC50 values as low as 0.02 µM. The high photodynamic activity of these compounds can be attributed to their high cellular uptake and low aggregation tendency in the biological media, which promote the generation of reactive oxygen species inside the cells. The effects of the chain length on the aggregation behaviour, photophysical properties, cellular uptake and in vitro photodynamic activities of this series of compounds have also been examined.
合成了一系列新的 1,4-二聚乙二醇化锌 (II) 酞菁并进行了光谱表征。衍生物 ZnPc[O(CH2CH2O)nMe]2 (n = 2, 4, ca. 12) 是通过相应的二取代邻苯二甲腈与过量未取代邻苯二甲腈在 Zn(OAc)2·2H2O 存在下混合环化制备的和1,8-二氮杂双环[5.4.0]十一碳-7-烯。另外两个类似物ZnPc[O(CH2CH2O)nMe]2 (n = 6, 8)是通过ZnPc[O(CH2CH2O)4H]2的链延长反应制备的。这些大环化合物高度可溶,并且在 DMF 中保持不聚集,如尖锐的 Q 波段吸收所示。与未取代的锌(II)酞菁相比,这些二-α-取代的类似物具有红移的Q带(689 nm vs. 670 nm),并且表现出相对较弱的荧光发射和较高的产生单线态氧的效率。光照后,这些化合物对 HT29 人结直肠癌和 HepG2 人肝癌细胞具有高度细胞毒性。具有中等长度取代基的化合物特别有效,IC50 值低至 0.02 µM。这些化合物的高光动力活性可归因于它们在生物介质中的高细胞摄取和低聚集倾向,从而促进细胞内活性氧的产生。还研究了链长对该系列化合物的聚集行为、光物理性质、细胞摄取和体外光动力活性的影响。