Synthetic Routes to N-9 Alkylated 8-Oxoguanines; Weak Inhibitors of the Human DNA Glycosylase OGG1
作者:Tushar Mahajan、Mari Ytre-Arne、Pernille Strøm-Andersen、Bjørn Dalhus、Lise-Lotte Gundersen
DOI:10.3390/molecules200915944
日期:——
The human 8-oxoguanine DNA glycosylase OGG1 is involved in base excision repair (BER), one of several DNA repair mechanisms that may counteract the effects of chemo- and radiation therapy for the treatment of cancer. We envisage that potent inhibitors of OGG1 may be found among the 9-alkyl-8-oxoguanines. Thus we explored synthetic routes to 8-oxoguanines and examined these as OGG1 inhibitors. The best reaction sequence started from 6-chloroguanine and involved N-9 alkylation, C-8 bromination, and finally simultaneous hydrolysis of both halides. Bromination before N-alkylation should only be considered when the N-substituent is not compatible with bromination conditions. The 8-oxoguanines were found to be weak inhibitors of OGG1. 6-Chloro-8-oxopurines, byproducts in the hydrolysis of 2,6-halopurines, turned out to be slightly better inhibitors than the corresponding 8-oxoguanines.
人类 8-氧代鸟嘌呤 DNA 糖基化酶 OGG1 参与碱基切除修复(BER),BER 是几种 DNA 修复机制之一,可以抵消化疗和放疗对癌症治疗的影响。我们设想,可能会在 9-烷基-8-氧代鸟嘌呤中发现有效的 OGG1 抑制剂。因此,我们探索了 8-氧代鸟嘌呤的合成路线,并将其作为 OGG1 抑制剂进行研究。最佳的反应顺序是从 6-氯鸟嘌呤开始,包括 N-9 烷基化、C-8 溴化,最后同时水解两种卤化物。只有当 N-取代基不符合溴化条件时,才应考虑在 N-烷基化之前进行溴化。研究发现,8-氧代鸟嘌呤是 OGG1 的弱抑制剂。2,6-卤代嘌呤水解过程中产生的副产物 6-氯-8-氧代嘌呤的抑制效果略好于相应的 8-氧代鸟嘌呤。