Systematic Evaluation of the Metabolism and Toxicity of Thiazolidinone and Imidazolidinone Heterocycles
作者:Shi Qing Tang、Yong Yang Irvin Lee、David Sheela Packiaraj、Han Kiat Ho、Christina Li Lin Chai
DOI:10.1021/acs.chemrestox.5b00247
日期:2015.10.19
The thiazolidine and imidazolidine heterocyclic scaffolds, i.e., the rhodanines, 2,4-thiazolidinediones, 2-thiohydantoins, and hydantoins have been the subject of debate on their suitability as starting points in drug discovery. This attention arose from the wide variety of biological activities exhibited by these scaffolds and their frequent occurrence as hits in screening campaigns. Studies have been conducted to evaluate their value in drug discovery in terms of their biological activity, chemical reactivity, aggregation-based promiscuity, and electronic properties. However, the metabolic profiles and toxicities have not been systematically assessed. In this study, a series of five-membered multiheterocyclic (FMMH) compounds were selected for a systematic evaluation of their metabolic profiles and toxicities on TAMH cells, a metabolically competent rodent liver cell line and HepG2 cells, a model of human hepatocytes. Our studies showed that generally the rhodanines are the most toxic, followed by the thiazolidinediones, thiohydantoins, and hydantoins. However, not all compounds within the family of heterocycles were toxic. In terms of metabolic stability, 5-substituted rhodanines and 5-benzylidene thiohydantoins were found to have short half-lives in the presence of human liver microsomes (t1/2 < 30 min) suggesting that the presence of the endocyclic sulfur and thiocarbonyl group or a combination of C5 benzylidene substituent and thiocarbonyl group in these heterocycles could be recognition motifs for P450 metabolism. However, the stability of these compounds could be improved by installing hydrophilic functional groups. Therefore, the toxicities and metabolic profiles of FMMH derivatives will ultimately depend on the overall chemical entity, and a blanket statement on the effect of the FMMH scaffold on toxicity or metabolic stability cannot and should not be made.
噻唑烷和咪唑烷杂环骨架,即罗丹宁、2,4-噻唑烷二酮、2-硫代海因和海因,其作为药物发现的起始点的适宜性一直是争论的主题。这种关注源于这些骨架所展现的多样化的生物活性和它们在筛选活动中频繁出现作为命中物。已经进行了研究来评估它们在药物发现中的价值,包括它们的生物活性、化学反应性、基于聚集的杂乱性以及电子性质。然而,它们的代谢轮廓和毒性尚未被系统地评估。在这项研究中,选择了一系列五元多杂环(FMMH)化合物,对它们在TAMH细胞(一种代谢能力健全的啮齿动物肝细胞系)和HepG2细胞(一种人肝细胞模型)上的代谢轮廓和毒性进行了系统评估。我们的研究表明,一般来说,罗丹宁的毒性最大,其次是噻唑烷二酮、硫代海因和海因。然而,并非所有杂环家族中的化合物都具有毒性。在代谢稳定性方面,发现5-取代的罗丹宁和5-苄叉基硫代海因在人肝微粒体存在下具有较短的半衰期(t1/2 < 30分钟),这表明在这些杂环中的环内硫和硫羰基或5位苄叉基取代和硫羰基的组合可能是P450代谢的识别基序。然而,通过引入亲水性功能基团可以提高这些化合物的稳定性。因此,FMMH衍生物的毒性和代谢轮廓最终将取决于整体化学实体,关于FMMH骨架对毒性或代谢稳定性的影响不能也不应该做出笼统的陈述。