Toxoflavins and Deazaflavins as the First Reported Selective Small Molecule Inhibitors of Tyrosyl-DNA Phosphodiesterase II
摘要:
The recently discovered enzyme tyrosyl-DNA phosphodiesterase 2 (TDP2) has been implicated in the topoisomerase-mediated repair of DNA damage. In the clinical setting, it has been hypothesized that TDP2 may mediate drug resistance to topoisomerase II (topo II) inhibition by etoposide. Therefore, selective pharmacological inhibition of TDP2 is proposed as a novel approach to overcome intrinsic or acquired resistance to topo II-targeted drug therapy. Following a high-throughput screening (HTS) campaign, toxoflavins and deazaflavins were identified as the first reported sub-micromolar and selective inhibitors of this enzyme. Toxoflavin derivatives appeared to exhibit a clear structure-activity relationship (SAP.) for TDP2 enzymatic inhibition. However, we observed a key redox liability of this series, and this, alongside early in vitro drug metabolism and pharmacokinetics (DMPK) issues, precluded further exploration. The deazaflavins were developed from a singleton HTS hit. This series showed distinct SAR and did not display redox activity; however low cell permeability proved to be a challenge.
Synthesis of 5-deazaflavin derivatives and their activation of p53 in cells
摘要:
A family of 5-deazaflavin derivatives has been synthesised using a two-step convergent strategy. The biological activity of these compounds was evaluated in cells, by assessing their ability to stabilize and activate p53. These compounds may act as low molecular weight inhibitors of the E3 activity of HMD2 in tumours that retain wild-type p53. Importantly, we have demonstrated that the nitro group present in all three of the original lead compounds [1-3 (HL198C-E)] is not essential for observation of this biological activity. (c) 2006 Elsevier Ltd. All rights reserved.
Herein, a highly efficient and environmentally benign protocol for the synthesis of biologically important pyrimido[4,5-b]quinolinone-2,4-diones fromaromatic amines, barbituric acid and aryl aldehyde is reported. This process takes place at room temperature under direct irradiationfrom a UV365 light source in the absence of a photocatalyst. The reported approach has several advantages such as high
在此,报道了一种由芳族胺,巴比妥酸和芳基醛合成生物上重要的嘧啶并[4,5 - b ]喹啉酮-2,4-二酮的高效,环保的方法。该过程在室温下在不存在光催化剂的情况下在来自UV 365光源的直接照射下进行。报道的方法具有许多优势,例如高收率,干净的反应条件,无色谱法合成以及使用便宜的水-甘油溶剂系统,它也是一种环境友好的溶剂。该协议适用于大规模合成嘧啶并[4,5 - b ]喹啉酮-2,4-二酮而不浪费任何昂贵的化学药品是一个附加的优势。
Synthesis of 5-deazaflavin derivatives and their activation of p53 in cells
作者:Jennifer M. Wilson、Graham Henderson、Fiona Black、Andrew Sutherland、Robert L. Ludwig、Karen H. Vousden、David J. Robins
DOI:10.1016/j.bmc.2006.10.011
日期:2007.1.1
A family of 5-deazaflavin derivatives has been synthesised using a two-step convergent strategy. The biological activity of these compounds was evaluated in cells, by assessing their ability to stabilize and activate p53. These compounds may act as low molecular weight inhibitors of the E3 activity of HMD2 in tumours that retain wild-type p53. Importantly, we have demonstrated that the nitro group present in all three of the original lead compounds [1-3 (HL198C-E)] is not essential for observation of this biological activity. (c) 2006 Elsevier Ltd. All rights reserved.
Toxoflavins and Deazaflavins as the First Reported Selective Small Molecule Inhibitors of Tyrosyl-DNA Phosphodiesterase II
作者:Ali Raoof、Paul Depledge、Niall M. Hamilton、Nicola S. Hamilton、James R. Hitchin、Gemma V. Hopkins、Allan M. Jordan、Laura A. Maguire、Alison E. McGonagle、Daniel P. Mould、Mathew Rushbrooke、Helen F. Small、Kate M. Smith、Graeme J. Thomson、Fabrice Turlais、Ian D. Waddell、Bohdan Waszkowycz、Amanda J. Watson、Donald J. Ogilvie
DOI:10.1021/jm400568p
日期:2013.8.22
The recently discovered enzyme tyrosyl-DNA phosphodiesterase 2 (TDP2) has been implicated in the topoisomerase-mediated repair of DNA damage. In the clinical setting, it has been hypothesized that TDP2 may mediate drug resistance to topoisomerase II (topo II) inhibition by etoposide. Therefore, selective pharmacological inhibition of TDP2 is proposed as a novel approach to overcome intrinsic or acquired resistance to topo II-targeted drug therapy. Following a high-throughput screening (HTS) campaign, toxoflavins and deazaflavins were identified as the first reported sub-micromolar and selective inhibitors of this enzyme. Toxoflavin derivatives appeared to exhibit a clear structure-activity relationship (SAP.) for TDP2 enzymatic inhibition. However, we observed a key redox liability of this series, and this, alongside early in vitro drug metabolism and pharmacokinetics (DMPK) issues, precluded further exploration. The deazaflavins were developed from a singleton HTS hit. This series showed distinct SAR and did not display redox activity; however low cell permeability proved to be a challenge.