聚(3-氨基-5-巯基-1,2,4-三唑)/多壁碳纳米管修饰的玻碳电极同时检测尿酸、黄嘌呤与次黄嘌呤

采用滴涂法得到多壁碳纳米管(MWCNTs)修饰的玻碳电极(GCE),通过电沉积方法将3-氨基-5-巯基-1,2,4-三唑(TA)沉积在MWCNTs/GCE表面,制备了聚(3-氨基-5-巯基-1,2,4-三唑)/多壁碳纳米管修饰电极(p TA/MWCNTs/GCE)。采用循环伏安法(CV)和示差脉冲伏安法(DPV),研究了尿酸(UA)、黄嘌呤(XA)和次黄嘌呤(HX)在该修饰电极上的电化学行为。结果表明,该修饰电极对UA、XA和HX均有较好的电催化活性作用,能实现对3种物质的同时测定。UA、XA和HX在该修饰电极上的线性范围分别为9.0~739.0、2.0~259.0、1.0~353.0μmol/L;检出限分别为0.67、0.17、0.33μmol/L。该修饰电极已成功用于尿液和血清实际样品中UA、XA和HX的同时测定,回收率为98.8%~105.5%。     

Synthesis,Structure and Biological Activity of 3-Methyl-4-(3-nitrobenzylideneamino)-5-ethoxycarbonyl-methylsulfanyl-1,2,4-triazole

A Schiff base was synthesized by 3-methyl-4-amino-5-ethoxycarbonyl-methylsulfanyl-1,2,4-triazole with 3-nitrobenzaldehyde. The structure was confirmed by 1H NMR, IR, H RMS, TGA techniques and X-ray diffraction. The crystal belongs to monoclinic system, space group P21/c, with a = 8.965(2), b = 21.903(5), c = 9.197(2) A, β = 114.011(4)°, C14H15N5O4 S, Mr = 349.08, V = 1649.7(6) A3, Dc = 1.407 g·cm-3, Z = 4, F(000) = 728, μ = 0.226 mm-1, the final R = 0.0574 and wR = 0.1336 for 2932 unique reflections with I 2σ(I). Furthermore, the biological activity to four vegetable pathogens has been tested. The title compound exhibits better biological activity to four vegetable pathogens compared to the Schiff base without 5-ethoxycarbonyl and to Gibberlla saubinetti in EC95 compared with triadimefon.     

Synthesis of 3,5-Diaryl-4-benzylideneamino-1,2,4-triazoles and 4-Amino-3,5-diaryl-1,2,4-triazoles

A one-pot reaction leading to 3,5-diaryl-4-benzylideneamino-1,2,4-triazoles is described, the key step of which is the reaction of arenecarbohydrazonoyl chloride with benzylidenehydrazide. Compounds obtained in this way were hydrolyzed to 4-amino-3,5-diaryl-1,2,4-triazoles.     

Pt(II) complexes of 4-amino-4H-1,2,4-triazole

The coordination ability of 4-amino-4H-1,2,4-triazole with Pt(II), both in solution and solid states, is elucidated by conventional and linear-polarized IR spectroscopy of oriented colloid suspensions in nematic host, ¹H- and ¹³C-NMR, UV-Vis spectroscopy, mass spectrometry (ESI and FAB), TGV, and DSC methods. The interpretation of the spectroscopic characteristics of corresponding metal complexes is obtained by comparison with free 4-amino-4H-1,2,4-triazole. In addition, quantum chemical calculations of the last compound are performed to obtain data for electronic structures and optical properties of the ligand, thus supporting the experimental elucidation. The evaluation of the cell viability on a panel of human tumor cell lines is made. The new Pt(II) complexes exerted cytotoxic effects in a concentration-dependent manner.     

Selective and Sensitive Determination of Paracetamol and Levodopa with Using Electropolymerized 3,5-Diamino-1,2,4-triazole Film on Glassy Carbon Electrode

For determination of levodopa (L-DOPA) and paracetamol (PAR), selective, effective and sensitive electrochemical sensor based on 3,5-diamino-1,2,4-triazole (35DT) on glassy carbon (GC) electrode was reported. The DPV method was used to obtain the oxidation peak current of L-DOPA which increased linearly with its concentration at the range of 1–99 μM and 99–480 μM. The linear relationship between the concentration of PAR and its peak current was obtained in the range of 0.3–55 μM and 55–475 μM. The limit of detection values for PAR and L-DOPA were found to be 0.1 and 0.25 μM, respectively. Satisfactory results were obtained in pharmaceutical samples.     

二乙酸·二(4-氨基-1,2,4-三唑)合锌(Ⅱ)配合物的制备、晶体结构、比热容及热力学性质

利用4-氨基-1,2,4-三唑(4-ATZ)的乙醇溶液与乙酸锌的甲醇溶液合成了标题化合物Zn(4-ATZ)_2(CH_3COO)_2,并培养出单晶,通过X射线单晶结构分析法测定晶体结构,晶体属于正交晶系,空间群为Aba2,晶胞参数为:a=0.767 32(7)nm,b=1.66444(16)nm,c=1.09040(11)nm,V=1.3926(2)nm~3,D_c=1.936 g·cm~(-3),Z=4,F(000)=720,R_1=0.0246,wR_2=0.0675。运用Micro-DSCⅢ微热仪测定配合物的比热容,在283～353 K时,比热容随温度呈二次方关系,其关系式为:C_p/(J·g~(-1)·K~(-1))=-2.021915+1.749228×10~(-2)T-2.358752×10~(-5)T~2,298.15 K时配合物的标准摩尔比热容为385.62 J·mol~(-1)·K~(-1)。     

Derivatives of 4-amino-4H-1,2,4-triazole-3-thiols linked to the pyrrole cycle and some products of their S-alkylation

This study offers an access to 21 new heterocyclic compounds representing pyrrole derivatives of 4-amino-4H-1,2,4-triazole-3-thiols or 1,3,4-oxadiazole-2-thiols. The principal synthetic approach is based on the cyclization of substituted potassium 2-(pyrrolecarbonyl)hydrazine-1-carbodithionate with hydrazine hydrate to 5-(substituted pyrrolyl)-4-amino-4H-1,2,4-triazole-3-thiols, followed by S-alkylation with methyl iodide or benzyl chloride. Among the resulted thirteen S-alkyl derivatives, five 1,3,4-oxadiazole derivatives have been isolated as secondary products and their formation is explained as being the result of S-alkylation of intermediate 1,3,4-oxa-diazole-2-thiols, generated in the alkaline medium. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 383–391, March, 2007.     

Synthesis and Crystal Structure Analysis of 4-Dibenzaldehydeamino-4H-1,2,4-triazole Diacetate

The new title compound 4-dibenzaldehydeamino-4H-1,2,4-triazole diacetate （C16H18N8O4,Mr = 386.38） has been prepared and its crystal structure was determined by single- crystal X-ray diffraction. The crystal is of monoclinic,space group P21/n with a = 8.1371（17）,b = 7.1237（12）,c = 16.325 （2）A,β = 100.366（2）°,V = 930.9（3） A^3,Z = 2,Dc = 1.378,F（000） = 404,μ = 0.104 mm^-1,MoKa radiation （λ = 0.71073 ）,R = 0.0307 and wR = 0.1196 for 4632 observed reflections with I 〉 2σ（I）. X-ray diffraction analysis reveals that the molecule is not flat and the crystal structure is stabilized mainly by van der Waals interactions.     

Synthesis of 4-Amino-6-R-4,5-dihydro-3-phenacylthio-1,2,4-triazin-5-ones and 8H-3-R-7-Aryl-1,2,4-triazino[3,4-b][1,3,4]thiadiazin-4-ones

A study was carried out on the reaction of 4-amino-6-R-2,3,4,5-tetrahydro-3-thioxo-1,2,4-triazin-5-ones with halo ketones in alkaline media to yield 4-amino-6-R-4,5-dihydro-3-phenacylthio-1,2,4-triazin-5-ones, which then convert to 8H-3-R-7-aryl-1,2,4-triazino[3,4-b][1,3,4]thiadiazin-4-ones.     

Unexpected Direction of Iodocyclization of 3-Allylthio-5-phenyl-4H-1,2,4-triazole

The reaction of 3-allylthio-5-phenyl-4H-1,2,4-triazole with iodine to give a mixture of 5,6-dihydro-5-iodomethyl-3-phenyl[1,3]thiazolo[2,3-c][1,2,4]triazole, 6,7-dihydro-6-iodo-3-phenyl-5H-[1,2,4]triazolo[3,4-b][1,3]thiazine, 5,6-dihydro-6-iodomethyl-2-phenyl[1,3]thiazolo[3,2-b][1,2,4]triazole, and 6,7-dihydro-6-iodo-2-phenyl-5H-[1,2,4]triazolo[5,1-b][1,3]thiazine has been studied. The structure of the products obtained was established using ¹H NMR spectroscopy of their dehydriodination products.     

5-取代-1H-1,2,4-三氮唑-3-羧酸的合成

三氮唑类化合物具有很强的生物活性[1,2],尤其是利用5 氨基 1H 1,2,4 三氨唑 3 羧酸为原料制得的Schiff碱具有较强的生根性能和较好的细胞分裂活性[3,4]本文以5 氨基 1H 1,2,4 三氨唑 3 羧酸为原料,经Sandmeyer反应将 NH2转变 Cl、 Br、 I和 CN。其合成路线如下:1　实验部分1 1　仪器与试剂Impact 420型傅里叶红外光谱仪;HP8452A二极管阵列紫外/可见光光度计;PE 2400型元素自动分析仪:XL 200MHz超导核磁共振仪;M 80AGC/MS质谱仪。5 氨基 1H 1,2,4 三氮唑 3 羧酸(工业纯,武汉中储鹤翔新技术有限公司,纯度95%以上),其余试剂均…     

对乙酰氨基酚在活化玻碳电极上的电化学行为及测定

应用循环伏安法,研究了对乙酰氨基酚(PCT)在活化玻碳电极上的电化学行为.在pH=4.00的HAc-NaAc缓冲溶液中,PCT的CV扫描于0.54 V左右出现一对明显的氧化-还原峰.电极反应为2电子、2质子的受吸附控制的准可逆过程.其氧化峰电流与PCT浓度在8.00×10-6~2.00×10-4mol.L-1范围内呈良好的线性关系,相关系数r=-0.99918;检出限为6.34×10-6mol.L-1.用于药物样品PCT的含量测定,结果满意.     

Synthesis,crystal structures and thermal stabilities of zinc coordination polymers containing the 3-hydrazino-4-amino-1,2,4-triazole ligand

Two zinc coordination polymers, {[Zn(HATr)₂](NO₃)₂}_n (1) and {[Zn₂(HATr)₄](ZnCl₄)(NO₃)₂·H₂O}_n (2), were synthesized from reactions of 3-hydrazino-4-amino-1,2,4-triazole dihydrochloride (HATr·2HCl) with Zn(NO₃)₂. The polymers were characterized by single-crystal X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), elemental analysis, and differential scanning calorimetry. The crystal structures revealed that 1 and 2 have 1-D-chain structures, which were further assembled to form 3-D-frameworks by hydrogen bonds. Thermal analyses showed that these two compounds have thermal stability up to 280 °C. The energies of combustion, enthalpies of formation, critical temperatures of thermal explosion, entropies of activation (ΔS^≠), enthalpies of activation (ΔH^≠), and free energies of activation (ΔG^≠) were also measured and calculated. Furthermore, the sensitivities of 1 and 2 toward impact, friction, and static were determined, which revealed that 1 and 2 were less sensitive than Ni(N₂H₄)₃(NO₃)₂.     

Reaction of 3-Arylmethylidene-3H-furan-2-ones with 3-Amino-1,2,4-triazole as a Convenient Technique to Synthesize Condensed Diazepinones

The interaction of the arylmethylidene derivatives of 3H-furan-2-ones with 3-amino-1,2,4-triazole was studied. The structure of the final products depends on reaction conditions and reagent ratio.

Synthesis and Reactions of New Fused Heterocycles Derived from 5-Substituted-4-Amino-3-Mercapto-(4H)-1,2,4-Triazole with Biological Interest

The reaction of thiocarbohydrazide with carboxylic acids at the melting temperature allows an improved preparation of 5-substituted-4-amino-3-mercapto 1,2,4-triazoles 1 _{a ? g} . Compound 1 _a reacted with 2-bromopropionic acid to give acid derivative 2 . The latter was reacted with a mixture of acetic anhydride and triethylamine to afford the mesoionic compound 3 . Heating of compound 3 in ethanol gave the ester derivative 4 , which on alkaline hydrolysis in methanol gave ketone derivative 5 . Substituted 1,2,4-triazolo [3,4-b]-6H-1,3,4-thiadiazine 6 _h,i and 7 were synthesized by reaction of 1 _a with acetylacetone, ethyl acetoacetate and chloroacetamide. Heterocyclic systems 8 and 9 were prepared through the reaction of 1 _a with 2,3-dichloro-1,4-naphthoquinone and 2,3-dichloroquinoxaline. In addition, thenoyl isothiocyanate, thenoyl chloride, 2-thiophenecarbaldehyde, and p-chlorophenyl isocyanate reacted with compound 1 _a to afford 1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole ring system 10 , 11 , and urea derivative 12 . 1,2,4-Triazolo[3,4-b]-5H-pyrazole derivatives 14 _j,k were prepared through the reaction of compound 1 _a with 3-chloro-2,4-pentandione and ethyl-2-chloroacetoacetate. Compound 14 _j was treated with hydrazine to afford products 15 , 16 , and 17 depending on the type of hydrazine derivative and reaction conditions. Compound 19 was synthesized by refluxing of compound 14 _j with hydroxylamine hydrochloride to afford the corresponding oxime derivative 18 followed by treatment with thenoyl chloride.     

3-取代硫基-5-(1-羟基苯基)-4H-1,2,4-三唑类化合物的合成及抑菌活性

依据邻羟基二苯醚及三唑类化合物的抗菌特性及生物活性叠加原理, 将邻羟苯基和1,2,4-三唑分子片断有机结合, 设计合成了12个新型3-取代硫基-5-(1-羟基苯基)-4H-1,2,4-三唑类化合物. 首先, 水杨酸甲酯与水合肼反应生成水杨酰肼, 水杨酰肼再与硫氰酸铵和盐酸反应, 生成5-(1-羟基苯基)-4H-1,2,4-三唑-3-硫酮(3), 最后在碱性条件下化合物3与取代苯乙酮、氯苄和碘甲烷发生烷基化反应生成目标化合物, 化合物结构经 1H NMR及IR等表征确认. 抑菌测试结果表明, 当化合物质量分数为0.01%时, 目标化合物对白色念珠菌和大肠杆菌的抑菌率高达90%, 具有强抑菌活性; 对金黄色葡萄球菌的抑菌率高达80%, 具有一定的抑菌活性.     

Synthesis, structure and biological activity of 1-(1-methoxy-1-ferrocenyl-3-arylpropan-2-yl)-1H-1,2,4-triazole derivatives

A total of eleven new 1-(1-methoxy-1-ferrocenyl-3-arylpropan-2-yl)-1H-1,2,4-triazole derivatives have been synthesized from acetylferrocene. The structures of the title compounds have been determined by elemental analysis, ¹H-NMR and single crystal X-ray diffraction analysis. Bioassay showed that some of the title compounds had high plant-growth regulatory activity. __________ Translated from Chinese Journal of Organic Chemistry, 2005, 25(8) (in Chinese)     

Effect of H-bond formation on the electronic spectra of some azo compounds derived from 3-amino-1,2,4-triazole

The UV-visible spectra of some azo compounds derived from 3-amino-1,2,4-triazole and various active-methylene or active-hydrogen compounds have been investigated in organic solvents of different polarities. The spectral bands obtained are assigned to the possible electronic transitions. It was found that the azo compounds containing the acetylacetone moiety exist mainly in the hydrazone form, while those containing ethylcyanoacetate, or -naphthol substituents exist in an azo hydrazone tautomeric equilibrium in solution. The extra visible band exhibited in the spectra ofo-hydroxyazo compound is assigned to an intermolecular electronic transition. The spectral shifts observed in the various organic solvents are discussed on the basis of the solute-solvent interaction through the formation of hydrogen bonds with different species. The variation of the absorbance with pH is employed to determine the acid dissociation constants.