mercaptopurine has been researched along with 2-thioxanthene* in 1 studies
1 other study(ies) available for mercaptopurine and 2-thioxanthene
| Article | Year |
|---|---|
Nature and position of functional group on thiopurine substrates influence activity of xanthine oxidase--enzymatic reaction pathways of 6-mercaptopurine and 2-mercaptopurine are different.
Xanthine oxidase-catalyzed hydroxylation reactions of the anticancer drug 6-mercaptopurine (6-MP) and its analog 2-mercaptopurine (2-MP) as well as 6-thioxanthine (6-TX) and 2-thioxanthine (2-TX) have been studied using UV-spectroscopy, high pressure liquid chromatography, photodiode array, and liquid chromatography-based mass spectral analysis. It is shown that 6-MP and 2-MP are oxidatively hydroxylated through different pathways. Enzymatic hydroxylation of 6-MP forms 6-thiouric acid in two steps involving 6-TX as the intermediate, whereas 2-MP is converted to 8-hydroxy-2-mercaptopurine as the expected end product in one step. Surprisingly, in contrast to the other thiopurines, enzymatic hydroxylation of 2-MP showed a unique hyperchromic effect at 264 nm as the reaction proceeded. However, when 2-TX is used as the substrate, it is hydroxylated to 2-thiouric acid. The enzymatic hydroxylation of 2-MP is considerably faster than that of 6-MP, while 6-TX and 2-TX show similar rates under identical reaction conditions. The reason why 2-MP is a better substrate than 6-MP and how the chemical nature and position of the functional groups present on the thiopurine substrates influence xanthine oxidase activity are discussed. Topics: Animals; Cattle; Chromatography, High Pressure Liquid; Mass Spectrometry; Mercaptopurine; Models, Molecular; Molecular Structure; Purine Nucleosides; Purines; Sulfhydryl Compounds; Thioxanthenes; Time Factors; Xanthine Oxidase | 2007 |