蛋氨酸合成酶催化反应研究VII.5-氨基-6-甲基尿嘧啶的合成研究

报道了5-氨基-6-甲基尿嘧啶简便的合成方法。该化合物以6-甲基尿嘧啶（2） 为起始物，经硝化或重氮化分别得到了中间体5-硝基-6-甲基尿嘧啶（3）和5-偶氮 苯基-6-甲基尿嘧啶(4)，化合物3和4经Na_S_2O_4还原，合成产物5-氨基-6-甲基尿 嘧啶（1）。     

蛋氨酸合成酶催化反应研究Ⅳ.5-氨基-6-(3-丁烯基)尿嘧啶的合成研究

本工作中,5-氨基-6-(3-丁烯基)尿嘧啶(5)是合成蛋氨酸合成酶(MS)抑制剂的重要中间体,也是生物评估分析蛋氨酸合成酶及胸腺嘧啶合成酶的对比化合物[1],由于化合物(5)的合成未见文献报道,作者首先试用了以6-甲基尿嘧啶为原料,经1,3位保护后,利用6-甲基上氢的活性在二异丙氨基锂(LDA)的作用下,产生碳负离子,然后与3-氯丙烯发生亲核反应生成化合物(5)的合成路线.     

1,3-二(乙氧基甲基)-5-N,N-二甲氨基-6-甲基尿嘧啶的合成

报道了1,3-二(乙氧基甲基)-5-N,N-二甲氨基-6-甲基尿嘧啶方便、高产率的合成方法. 以6-甲基尿嘧啶(1)为起始物, 经硝化、嘧啶N¹,N ³-烷基化、还原及氨基甲基化, 首次高产率合成了1,3-二(乙氧基甲基)-5- N,N -二甲氨基-6-甲基尿嘧啶(5), 并对其化学结构进行了表征.     

HIV-1 RT抑制剂研究I.1,3-二苄基-6-(3,4-环氧丁基)尿嘧啶的合成

报道了1,3-二苄基-6-(3,4-环氧丁基)尿嘧啶的合成新方法.以6-甲基尿嘧啶(1)为起始物,经1,3-二苄基-6-甲基尿嘧啶(2)及未见文献报道的1,3-二苄基-6-(3-丁烯基)尿嘧啶(3)和1,3-二苄基-6-(3-羟基-4-溴丁基)尿嘧啶(4),首次高收率合成了1,3-二苄基-6-(3,4-环氧丁基)尿嘧啶(5),并对其化学结构进行了表征.     

蛋氨酸合酶催化反应研究Ⅵ.3-N-取代-6-甲基尿嘧啶的合成

首次报道了以苄氧羰氧次甲基作为6-甲基尿嘧啶环上N1位的保护基.选择性的在尿嘧啶环上N1保护、N3取代及N1脱保护等反应都在简便、高收率条件下进行,经四步反应高选择性地合成了3-N-取代-6-甲基尿嘧啶.     

蛋氨酸合酶催化反应研究VI.3-N-取代-6-甲基尿嘧啶的合成

首次报道了以苄氧羰氧次甲基作为6-甲基尿嘧啶环上N1位的保护基．选择性的在尿嘧啶环上N1保护、N3取代及N1脱保护等反应都在简便、高收率条件下进行，经四步反应高选择性地合成了3-N-取代-6-甲基尿嘧啶。     

5-甲氧基-2-[(E)-(6-甲基吡啶-2-亚氨基)甲基]苯酚的合成与表征

研究了以2-羟基-4-甲氧基苯甲醛和2-氨基-6-甲基吡啶为原料合成新型席夫碱化合物5-甲氧基-2-[(E)-(6-甲基吡啶-2-亚氨基)甲基]苯酚的方法。当2-羟基-4-甲氧基苯甲醛与2-氨基-6-甲基吡啶摩尔比为1∶1.6,反应时间为6 h,反应温度为75℃时,反应产率最高。采用元素分析、UV-Vis、IR、1H NMR、X-射线单晶衍射等方法进行结构表征。该化合物为单斜晶系,空间群P21/c,a=1.1886(3)nm,b=0.65948(16)nm,c=1.6897(4)nm,β=108.505(3)°,V=1.2560(5)nm3,Dc=1.281 g·cm-3,Z=4,F(000)=512,μ=0.087 mm-1,R1=0.0477,wR2=0.1342。通过π···π堆积和分子内氢键O2-H2···N1、C8-H8A···N2形成较稳定的晶体结构,并具有蓝色荧光。     

蛋氨酸合成酶催化反应研究Ⅴ：5-氨基-6-（3-羟基-4-溴丁基）尿嘧啶的合成研究

报导了5-氨基-6-（3-丁烯基）尿嘧啶、5-氨基-6-（3-羟基-4-溴丁基）尿嘧 啶的合成方法。以γ-取代的β-酮脂和O-甲基异尿硫酸盐为超始物，经6-取代尿嘧 啶（3）、6-取代-5-偶氮尿嘧啶（4）和未见文献报道的中间体6，首次合成了5-氨 基-6-（3-丁烯基）尿嘧啶（5）及5-氨基-6-（3-羟基-4-溴丁基）尿嘧啶（7）。     

5-取代苯氨基-6-甲基-1,2,4-三嗪-3-硫酮的合成

含有 1 ,2 ,4 三嗪结构的化合物具有广泛的生理活性。我们曾用α 乙酰基硫代甲酰芳胺为原料 ,合成了一系列三嗪类和其它杂环化合物 ,其中1 ,2 ,4 三嗪类有 4,6 二取代 5 硫酮 1 ,2 ,4三嗪 3 酮[1 ,2 ] ,3 氨基 5 取代苯氨基 6 苯基 1 ,2 ,4 三嗪[3] 等化合物。本文以α 乙酰基硫代甲酰芳胺为原料 ,进一步合成 5 取代苯氨基 6 甲基 1 ,2 ,4 三嗪 3 硫酮。当乙酰基硫代甲酰芳胺 1 (ａ ｇ)与氨基硫脲 2反应时 ,首先生成缩氨基硫脲 3(ａ ｇ) ,然后环化得到 5 取代苯氨基 6 甲基 1 ,2 ,4 三嗪 3硫酮 4(ａ ｇ) ,合成中发现 ,4(ａ ｇ)可…     

3-甲基-4-氨基-5-亚硝基尿嘧啶电化学还原反应

我们曾对4-氨基-5-亚硝基尿嘧啶系列物在高超电势下的还原机理做过一些研究^[1,2]。在低超电势下的还原机理尚未见报道。本工作用伏安法及恒电流阶跃法探讨了酸性介质中,3-甲基-4-氨基-5-亚硝基尿嘧啶(简写为3-MU)在低超电势范围内的还原历程。     

The Benzoylation of 6-Methyluracil and 5-Nitro-6-methyluracil

6-Methyluracil and 5-nitro-6-methyluracil react with variable molar quantities of benzoyl chloride in acetonitrile-pyridine at room temperature to give I-N, 3-N-dibenzoyl-6-methyluracil 3b and l-N-benzoyl-5-nitro-6-methyluracil 4b. The reactive rates of debenzoylation of 3b and 4b were investigated.     

Experimental and quantum-chemical study of the mechanism of oxidation of 5-hydroxy-6-methyl-uracil by molecular oxygen in the presence of copper(II) ions

It has been discovered experimentally that 5,5,6-trihydroxy-6-methylpyrimidine-2,4-dione is formed on oxidizing 5-hydroxy-6-methyluracil with molecular oxygen in aqueous medium in the presence of copper(II) chloride. Ab initio and DFT calculations on the 6-31G* basis, both in the gas phase and allowing for solvent, showed that the process proceeds with the direct participation of an activated oxygen molecule on the complex CuCl₂·(5-hydroxy-6-methyluracil)2. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 586-593, April, 2009.     

Reactions of 1,3-bis(ω-bromoalkyl)-6-methyluracils with 2-(dialkylamino)ethylphosphonates and 2-(dialkylamino)ethyl phosphates

1,3-Bis(4-bromobutyl)-6-methyluracil reacts with diethyl 2-(dimethylamino)ethylphosphonate to form a bisquaternary ammonium salt, whereas the reaction of 1,3-bis-(6-bromohexyl)-6-methyluracil with diethyl 2-(diethylamino)ethyl phosphate gives 1,3-bis-[(6-diethoxyphosphoryloxy)hexyl]-6-methyluracil and 1,1,4,4-tetraethylpiperazinium dibromide. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1130–1132, June, 2000.     

A new synthesis of 5-hydroxy-6-methyluracil

Dehydration of 5,6-dihydro-5,6-dihydroxy-6-methyl- and 5,6-dihydro-5,6-dihydroxy-1,3,6-trimethyl-uracil in 0.4 M aqueous sulfuric acid gives 5-hydroxy-6-methyl- and 5-hydroxy-1,3,6-trimethyluracil in quantitative yields. Two possible mechanisms have been examined using the mPW1k/6-311+G(2df,2pd)//mPW1k/6-31+G(d,p) method for the transformation of methylated and non-methylated 5,6-dihydro-5,6-dihydroxy-6-methyluracils into the corresponding 5-hydroxy-6-methyluracils. The first is a hydride C5-C6 shift occurring in concert with the loss of a water molecule and formation of the corresponding protonated 5,6-dihydro-5-oxo-6-methyluracils. The second is an acid-catalyzed dehydration reaction to yield 5-hydroxy-6-methyluracils. The calculations demonstrated that the second pathway was energetically most favorable.     

Thermochemical study of 5-methyluracil, 6-methyluracil, and 5-nitrouracil

The standard (p° = 0.1 MPa) molar enthalpies of formation, in the crystalline phase, at T = 298.15 K, for 5-methyluracil, 6-methyluracil, and 5-nitrouracil were derived from the values of the standard massic energies of combustion measured by static bomb combustion calorimetry. The results obtained together with literature values of the enthalpies of sublimation yielded the standard molar enthalpies of formation, in gaseous phase, at T = 298.15 K. These values are discussed in the terms of structural enthalpic increments.     

Computer-assisted prediction of antioxidant activities and toxicities of ionol, 5-hydroxy-6-methyluracil, and their derivatives

A mathematical model for prediction of antioxidant activity (AOA) with a recognition level of ∼90% was developed using the SARD-21 computer system. Based on this model, structural modification of ionol and 5-hydroxy-6-methyluracil was carried out. A set including 32 potential antioxidants was generated. The interval levels of toxicity were theoretically predicted and the effect of structural fragments on the toxic properties of the most efficient potential antioxidants was analyzed. Structural attributes characteristic of highly efficient, low-toxicity antioxidants were revealed for the first time. Based on complex analyses of the AOA and toxicity, thirteen structures of potentially efficient low-toxicity antioxidants were proposed. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1274–1279, August, 2006.     

The synthesis and properties of certain N-methylated 5-diazouracils

The reduction of 1-methyl-, 3-methyl- and 1,3-dimethyl-5-nitrouracil (Ia-c) to the corresponding 5-aminouracils (IIa-c) is described. Diazotization of 5-amino-1-methyluracil (IIa) and 5-amino-1,3-dimethyluracil (IIc) gave 5-diazouracils which were characterized as thermally stable C6 covalent hydrates (III and XIII). Diazotization of 5-amino-3-methyluracil (IIb) gave anhydro 5-diazo-3-methyluracil (X) which underwent covalent methanolation and thermally reversible covalent hydration. Treatment of III and XIII with hot methanol resulted in solvent exchange of the C6 hydroxyl groups by a mechanism which may involve initial formation of diazoethers. Treatment of the methanolates (IV, XI and XIV) with dimethylamine resulted in coupling at the diazo group with a concomitant expulsion of the C6 methoxyl groups to give 5-(3,3-dimethyl-1-triazeno)uracils (XVa-c).