Synthesis of N4-Amino and N4-Hydroxy Derivatives of 5-Azacytidine. A Facile Rearrangement of the N4-Amino Derivative to 5-(3-β-D-Ribofuranosylureido)-1H-1,2,4-triazole
Zinc monoglycerolate as a catalyst for the conversion of 1,3- and higher diols to diurethanes
作者:Sanjitha Kulasegaram、Uzma Shaheen、Terence W. Turney、Will P. Gates、Antonio F. Patti
DOI:10.1039/c5ra05032d
日期:——
An efficient approach to the synthesis of diurethanes from 1,3- and higher diols (n ≥ 3) is described.
一种从1,3-和更高的二醇(n ≥ 3)合成二尿酰胺的高效方法被描述。
Nitration of 2-Substituted Pyrimidine-4,6-diones, Structure and Reactivity of 5,5-<i>gem</i>-Dinitropyrimidine-4,6-diones
作者:Abraham Langlet、Nikolaj V. Latypov、Ulf Wellmar、Ulf Bemm、Patrick Goede、Jan Bergman、Ivan Romero
DOI:10.1021/jo025952x
日期:2002.11.1
in high yields. The gem-dinitro products were easily attacked by nucleophiles with concomitant formation of gem-dinitroacetyl derivatives, which in turn could be further hydrolyzed to salts of dinitromethane and triureas.
Reactions of Peroxynitrite with Uric Acid: Formation of Reactive Intermediates, Alkylated Products and Triuret, and In Vivo Production of Triuret Under Conditions of Oxidative Stress
作者:Christine Gersch、Sergiu P. Palii、Witcha Imaram、Kyung Mee Kim、S. Ananth Karumanchi、Alexander Angerhofer、Richard J. Johnson、George N. Henderson
DOI:10.1080/15257770902736400
日期:2009.3.11
were identified using liquid chromatography-mass spectrometry (LC-MS) analyses. The reactions generate reactive intermediates that yielded triuret as their final product. We also found that the antioxidant, ascorbate, could partially prevent this reaction. Whereas triuret was preferentially generated by the reactions in aqueous buffers, when uric acid or 1,3-15N2-uric acid was reacted with peroxynitrite
高尿酸血症与高血压、代谢综合征、先兆子痫、心血管疾病和肾脏疾病有关,所有疾病都与氧化应激有关。我们假设尿酸,一种已知的抗氧化剂,在与氧化剂反应后可能会变成促氧化物质;并且,从而促成这些疾病的发病机制。尿酸和 1,3- 15 N 2-尿酸在不同的缓冲液中和在酒精、抗氧化剂和人血浆中与过亚硝酸盐反应。使用液相色谱-质谱(LC-MS)分析鉴定反应产物。反应产生反应性中间体,产生三脲作为其最终产物。我们还发现抗氧化剂抗坏血酸可以部分阻止这种反应。而三脲优先由水性缓冲液中的反应产生,当尿酸或 1,3- 15 N 2-尿酸在醇存在下与过亚硝酸盐反应,得到烷基化醇作为最终产物。通过扩展,该反应可以烷基化其他含有 OH 基团的生物分子和其他含有不稳定氢的生物分子。还发现患有先兆子痫(一种与氧化应激相关的妊娠特异性高血压综合征)受试者尿液中的三脲升高,而正常健康志愿者中很少产生三脲。我们得出结论,在氧化应激
Methods And Devices For Preparing Biuret And Cyanuric Acid
申请人:Lee Chun Hyuk
公开号:US20080039623A1
公开(公告)日:2008-02-14
Provided are methods and devices for preparing biuret and cyanuric acid by thermal decomposition of urea. Specifically, a product of thermal decomposition is cooled to precipitate a crystal and the precipitated crystal is dissolved using an alkali aqueous solution and cooled to obtain biuret having high purity. Furthermore, the cyanuric acid that is one of byproducts by the thermal decomposition of urea is effectively recovered with high purity.
Sn(IV) porphyrins ([Sn(IV)TTP(3PyO)2] (5) and [Sn(IV)TPP(3PyO)2] (6) [tetrathienylporphyrin (TTP), tetraphenylporphyrin (TPP), and pyridyloxy (PyO)]) were prepared and characterized and their photocytotoxicity upon irradiation with 625 nm light has been studied. The presence of the 3PyO axial ligands was found to limit the aggregation and enhance the solubility of 5 and 6 in DMF/H2O (1 : 1). The photophysical
Sn( IV ) 卟啉 ([Sn( IV )TTP(3PyO) 2 ] ( 5 ) 和 [Sn( IV )TPP(3PyO) 2 ] ( 6 ) [四噻吩基卟啉 (TTP)、四苯基卟啉 (TPP) 和吡啶氧基 (PyO) )]) 的制备和表征,并研究了它们在 625 nm 光照射下的光细胞毒性。发现3PyO轴向配体的存在限制聚集并增强5和6在DMF/H 2 O(1:1)中的溶解度。比较了内消旋-2-噻吩基和内消旋-苯基取代的Sn( IV )卟啉的光物理性质和光动力治疗(PDT)活性。当用 Thorlabs M625L3 LED 在 625 nm 照射时,发现5和6在 MCF-7 癌细胞中具有光细胞毒性,但在黑暗中保持无毒。发现Sn( IV )内消旋-四-2-噻吩基卟啉5的 PDT 活性相对于其类似的四苯基卟啉6显着增强。由于内消旋-2-噻吩基环,5的Q 00带明显红移至治疗窗口,并且5在DMF中具有异常高的单线态氧量子产率值0