Design,Synthesis And Biological Evaluation Of Organelle-Targeted Polyamine Conjugates Based On Aromatic Heterocyclic Rings

Studies have shown that polyamines,which including cadaverine,putrescine,spermine and spermidine,can selectively accumulate in tumor tissue and high levels of polyamines can promote tumor growth and metastasis.In view of the uptake,intracellular synthesis and metabolism of exogenous polyamines in tumor cells,natural or synthetic polyamine-targeted anti-tumor drugs have been discovered.The natural product,squalantamine and the"podophyllotoxin-polyamine"conjugate F14512,containing polyamine units in the structure,have entered the clinical research stage.Recent studies have found that some polyamine conjugates with fluorescent probe function exhibit different organelle targeting,which can target mitochondria,lysosomals,nuclei,etc.respectively.Therefore,the design and synthesis of polyamine conjugates based on polyamine structure is one of the main directions of drug research in the field of polyamines.This subject briefly describes the structure,physiological function,metabolic pathways and connections between polyamines and tumors,and introduces anti-tumor drugs designed by polyamine.Taking the previously reported"Anthracene-polyamine"conjugates ANT44（B13）and ANT444（B14）as the lead compound,6 kinds of different naphthalene-based bicyclic aromatic mother nucleus and 3 types of anthracene tricyclic aromatic mother nucleus were selected,which were coupled with 7 kinds of polyamine chains in different ways to form polyamine conjugates with fluorescent probes and anti-tumor activity,and a total of 34 target compounds were synthesized,of which 29 were not reported.Its structure was confirmed by techniques such as ¹H NMR,¹³C NMR and MS,etc.In order to analyze the relationship between"structure-organelle localization-mechanism of action",three kinds of tumor cells,including hepatocellular carcinoma cells（Hep G2）,cervical cancer cells（Hela）and human esophageal squamous cell carcinoma cells（EC109）,the MTT method was used to conduct a preliminary anti-tumor activity screening of the target compounds.Then 13 compounds（containing ANT44 and ANT444）were selected to further test the IC₅₀ values in Hep G2 and EC109 cells,which found that the vitro anticancer activity of"Fluorene-polyamine"conjugates B24 and"Carbazole-polyamine"B34 is superior to the lead compound B13 and B14.Then the organellelocalization experiments of the"Anthracene-polyamine"conjugates B13,B14,B15 and the"Carbazole-polyamine"conjugate B34 were completed in Hep G2 cells:B13 and B14 could be localized with lysosomes and nuclei,but kinetic experiments of B14showed that it was first localized in lysosomes and then transferred to nucleus;B15 and B34were mainly localized in lysosomes.Finally,experiments with B24 and B34 in combination with 2 autophagy inhibitors showed that autophagy inhibitors had little effect on B24,but B34may lead to cell death by inducing autophagy.The above results suggest that the polyamine conjugates designed are mainly lysosomal targets,but the aromatic heterocyclic groups and polyamine structures have an impact on the uptake rate,intracellular distribution and action mechanism of the compounds.