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1.
1,2,4-三唑类化合物在农药、医药及化工领域有着广泛的应用,其与-些金属离子形成的配合物具有自旋转换功能。为了制备研究新的具有自旋转换功能的1,2,4-三唑配合物,以a-吡啶甲酸为原料,经多步反应合成3-甲基-4-对甲苯基-5-(2-吡啶基)-1,2,4-三唑,并用IR、MS、^1H—NMR对其结构进行了确证。  相似文献   

2.
1,2,4-三唑类化合物在农药、医药、生物、信息材料及化工领域有着广泛的应用,报道了3-苯基-4-对甲苯基-5-(2-吡啶基)-1,2,4-三唑的合成,并用红外、核磁(^1H—NNR、)及质谱对其结构进行了确证。  相似文献   

3.
Assembly of Cd(II) nitrate with a novel tripyridyltriazole building block 3-(2-pyridyl)-4,5-bis(4-pyridyl)-1,2,4-triazole (L1) and pseudohalide anion dicyanamide (dca) or azide (N3) yields two coordination polymers {[Cd(L1)2(dca)2](H2O)2}n (1) and {[Cd2(L1)(μ1,1-N3)21,3-N3)(N3)](H2O)1.5}n (2). Single crystal X-ray diffraction analysis indicates that the Cd(II) centers in 1 are bridged by the bidentate L1 ligands to form 1D arrays, which are further extended to a 3D network via hydrogen bonding and aromatic stacking. Significantly, the L1 ligands in 2 display the unusual pentadentate coordination and the azide anions take different μ1,1-, μ1,3-, and unidentate binding modes, interlinking the Cd(II) ions to afford a complicated 3D open framework with the inclusion of lattice water guests. Both complexes exhibit strong solid state fluorescent emissions at room temperature.  相似文献   

4.
Coordination polymers [Hg(L2)Cl2]n (1) and {[Hg2(L2)Cl4](DMF)}n (2) have been assembled from Hg(II) chloride and a novel tripyridyltriazole tecton 3,4-bis(2-pyridyl)-5-(4-pyridyl)-1,2,4-triazole (L2) in different solvent media. Both complexes have been characterized by IR, microanalysis, powder X-ray diffraction, and thermogravimetric analysis. Single crystal X-ray diffraction indicates that the L2 ligands take the (η3, μ2) and (η4, μ3) binding modes in 1 and 2, respectively, which connect the Hg(II) centers to afford linear and ladder-like 1D arrays. Interestingly, complex 1 exhibits strong solid state fluorescent emission at room temperature due to the intraligand transitions, whereas complex 2 is non-fluorescent.  相似文献   

5.
Two new azide complexes, [Cd2(3-abpt)(N3)4]n (1) and [Cu(3-abpt)2(N3)2] (2) (3-abpt = 4-amino-3,5-bis(3-pyridyl)-1,2,4-triazole), have been prepared and structurally characterized. Complex 1 displays an interesting 2D polymeric structure with rarely reported 3,7-connected (32;4)(34;46;56;65) network in the Schafli notation. Complex 2 contains mononuclear pieces, and they are linked each other through weak CuN coordination bonds to form a 2D sheet with (4, 4) topology. The thermal stability and fluorescent property of 1 have also been investigated.  相似文献   

6.
研究了第4代头孢菌素的关键中间体7位侧链酸——氨噻二唑肟乙酸衍生物的合成工艺。考察了多种催化剂在不同浓度条件下对水解反应的影响,结果表明适宜的水解反应催化剂为LiOH,同时使用氧化剂和相转移催化剂可使收率大幅提高,收率达到80%,产品纯度可达97%,质量明显优于其他方法。本工艺原料易得,操作简单,收率提高,产品质量优异,适合工业化生产。  相似文献   

7.
臧佳良 《河北化工》2012,35(1):24-25,28
(Z)-2-(5-氨基-1,2,4-噻二唑-3-基)-2-乙氧亚胺基乙酸是制备第5代头孢菌素头孢洛林酯的重要中间体,归纳总结了其合成方法。  相似文献   

8.
Novel thiophene-based oligomer, 2,2′-bis(2,2′-bithiophene-5-yl)-3,3′-bithianaphthene (TX), was designed and synthesized, and its electrochemical and spectral properties characterised. TX was readily polymerised electrochemically to form well organized conducting homopolymer films on various solid electrode substrates. Moreover, it was successfully used for deposition by electropolymerisation of electrochemically active thin films of co-polymers with three different monomers of functionalised bis(2,2′-bithienyl)methane derivatives. It appeared that TX was an effective crosslinker and 3D promoter in these electropolymerisations involving co-monomers intrinsically showing limited aptitude for the electropolymerisation or forming polymer films of low conductivity. This attractive TX ability stems from combination of its (i) high conjugation efficiency in each of the two planar moieties, (ii) intrinsic 3D structure on account of the presence of the central node, and (iii) intrinsic regioselectivity in electropolymerisation on account of the positions of the two available free α-thiophene sites.  相似文献   

9.
优化了头孢托罗活性硫酯-(Z)-2-(5-氨基-1,2,4-噻二唑-3-基)-2-三苯甲氧亚胺基硫代乙酸(S-2-苯并噻唑)酯(2)的合成工艺。以3-氨基-5-乙酰胺基异噁唑(3)为原料,与特戊酰基异硫氰酸酯经重排反应,制得N-乙酰基-2-(5-特戊酰胺基-1,2,4-噻二唑-3-基)乙酰胺(5),收率为72%;采用亚硝酸异丙酯对中间体5进行肟化、然后与三苯基氯甲烷进行醚化制得(Z)-N-乙酰基-2-(5-特戊酰胺基-1,2,4-噻二唑-3-基)-2-三苯甲氧亚胺基乙酰胺(7a),收率为78%;7a经碱性水解,制得(Z)-2-(5-氨基-1,2,4-噻二唑-3-基)-2-三苯甲氧亚胺基乙酸(8),收率为65%;,在乙腈与甲苯的混合溶剂中,8与亚磷酸三乙酯、二苯并噻唑二硫醚混合反应,制得活性硫酯2,路线的总收率达24%。该合成工艺具有反应条件温和,操作简便,易于分离等优点,因而有较好的工业化应用前景。  相似文献   

10.
A novel iron(II) complex, trans-[FeL2(NCS)2][FeL2(CH3OH)2](NCS)2 (1) with 4-amino-3-(p-chlorophenyl)-5-(2-pyridyl)-1,2,4-triazole (L) has been successfully synthesized and characterized. X-ray crystallography analysis shows that 1 is the first example in the mononuclear triazole-based complexes consisting of two distinct molecules: trans-[FeL2(NCS)2] and trans-[FeL2(CH3OH)2](NCS)2 with each octahedral iron(II) center coordinated axial by two NCS ions in Fe1 but two MeOH molecules in Fe2. Moreover, 1 can lose two MeOH molecules at 220 °C to form trans-[FeL2(NCS)2] (2) which can be transformed to 1 when recrystallizing 2 in methanol. Both 1 and 2 are high-spin species in the range of 1.8–300 K.  相似文献   

11.
12.
2-氯-5-(4-氯-1-甲基-5-三氟甲基-1H-吡唑-3-基)-4-氟苯甲醛是合成除草剂的中间体,它可以通过以下2步反应制得:首先,4-氯-3-(4-氯-2-氟-5-甲基苯基)-1-甲基-5-三氟甲基-1H-吡唑在乙酸/乙酐混合溶剂中用三氧化铬氧化,然后,在乙醇/水混合溶剂中,用碳酸氢钠催化水解得目的的产物,2步反应总收率达到71.6%。  相似文献   

13.
2-(5-Amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid 2-benzothiazolyl thioester(III), an important intermediate of the fourth generation cephalosporins, was efficiently synthesized by reacting 2-(5-amino-1,2,4-thiadiazol-3-yl)-2-(Z)-methoxyiminoacetic acid (I) with 2,2′-dibenzothiazole disulfide (II) in the presence of triphenylphosphine. Effects of reaction time, temperature, solvents, catalysts and feeding molar ratio on the yield and quality of products were investigated, and an improved procedure suitable for industrial production was established. Using 1,2-dichloroethane as solvent, triphenylphosphine as reducer, and triethylamine as catalyst, n(I): n(II): n(triphenylphosphine)51.0: 1.0: 1.0, the product was obtained at room temperature in 98.1% yield. The purity of the product without further purification is 98.7% determined by HPLC method. This procedure could be a suitable alternative to the traditional processes because of its easy handling, high yield and low cost. __________ Translated from Fine Chemicals, 2007, 24(8): 816–819 [译自:精细化工]  相似文献   

14.
以氨噻二唑肟乙酸(Ⅰ)与二硫化二苯并噻唑(Ⅱ)为原料,三苯基膦为还原剂,制备了第四代头孢菌素中间体氨噻二唑肟乙酸苯并噻唑硫酯(Ⅲ)。研究了溶剂、温度及原料投料比对该产物收率及质量的影响。结果表明,当以1,2-二氯乙烷作溶剂,n(Ⅰ)∶n(Ⅱ)∶n(三苯基膦)=1.0∶1.0∶1.0,反应在室温进行时,收率可达98.1%(基于Ⅰ计算),HPLC测定w(Ⅲ)=98.7%。在工艺改进的条件下,反应时间缩短,生产条件简化,收率得到较大提高,成本降低。  相似文献   

15.
Advanced glycation end products (AGEs) are associated with diabetes and its complications. AGEs are formed by the non-enzymatic reactions of proteins and reducing sugars, such as glucose and ribose. Ribose is widely used in glycation research as it generates AGEs more rapidly than glucose. This study analyzed the AGE structures generated from ribose-modified protein by liquid chromatography–quadrupole time-of-flight mass spectrometry. Among these AGEs, Nδ-(5-hydro-5-methyl-4-imidazolone-2-yl)-ornithine (MG-H1) was the most abundant in ribose-glycated bovine serum albumin (ribated-BSA) among others, such as Nε-(carboxymethyl) lysine, Nε-(carboxyethyl) lysine, and Nω-(carboxymethyl) arginine. Surprisingly, MG-H1 was produced by ribated-BSA in a time-dependent manner, whereas methylglyoxal levels (MG) were under the detectable level. In addition, Trapa bispinosa Roxb. hot water extract (TBE) possesses several anti-oxidative compounds, such as ellagic acid, and has been reported to inhibit the formation of MG-H1 in vivo. Thus, we evaluated the inhibitory effects of TBE on MG-H1 formation using ribose- or MG-modified proteins. TBE inhibited MG-H1 formation in gelatin incubated with ribose and ribated-BSA, but not in MG-modified gelatin. Furthermore, MG-H1 formation was inhibited by diethylenetriaminepentaacetic acid. These results demonstrated that ribose reacts with proteins to generate Amadori compounds and form MG-H1 via oxidation.  相似文献   

16.
介绍了4,5 二氢 3 甲基 1 (4 氯 2 氟苯基) 1,2,4 三唑 5(1H)酮的两种合成方法。以 2 氟 4 氯苯肼作为原料,1 (乙氧基)乙叉基氨基甲酸乙酯法收率82 6%,“一锅法”收率 81%,化合物经核磁证实了结构,并对两种方法做了比较。该化合物是合成超高效除草剂唑酮草酯的重要中间体。  相似文献   

17.
[方法]脲嘧啶类化合物和苯氧羧酸类化合物均具有较高的生物活性.为了寻找高效、低毒的除草活性化合物,以2,4-二氯苯胺和3-氨基-4,4,4-三氟甲基丁烯酸乙酯为原料,经关环、氮甲基化、硝化、还原得到中间体3-(5-胺基-2,4-二氯苯基)-6-(三氟甲基)-1-甲基嘧啶-2,4(1H,3H)-二酮,其与芳氧乙(丙)酰氯反应,合成了16个未见文献报道的N-[4氯-2-取代-5(3-甲基-2,6-二氧-4-三氟甲基-2,3-二氢嘧啶-1(6H)-基)苯基]-N-取代苯氧乙(丙)酰胺类化合物(31,所有目标化合物结构均通过1H NMR、IR、LC/MS确认.[结果]在75 g a.i./hm2剂量下芽后茎叶处理,化合物3d、3f、3i化合物对刺苋、藜双子叶杂草的抑制率达90%以上,表现出较好的抑制活性;化合物3d、3f对苘麻的抑制率分别达80%、90%,但是大部分化合物无活性.[结论]将具有不同除草机理除草活性的脲嘧啶结构与苯氧羧酸结构有机的结合起来,从生物活性来看,初步设计的化合物不是很成功,该类化合物的结构优化正在进行中.  相似文献   

18.
Reaction of 3-(2-pyridyl)pyrazole-5-carboxylic acid (H2L) with Zn(II) or Cu(II) perchlorate yielded [ZnL]n (1) and [CuL]n (2) with similar composition. The ligand L2  adopts the same μ3κ5 coordination mode. The Zn(II) and Cu(II) atom takes square pyramid coordination polyhedron with some discrepancy. Bigger difference in the dimeric secondary building blocks leads to distinct two-dimensional metal–organic frameworks. The Zn(II) complex fluoresces stronger than the free ligand. The Cu(II) polymer displays strong antiferromagnetic intra-dimer exchange and ferromagnetic inter-dimer exchange.  相似文献   

19.
介绍了显色剂5-(3,5-二溴-2-吡啶基)-1-(2-羟基-5-磺苯基)-3-(2-羟基苯基)甲(BPHPS)的合成。详细研究了试剂与铜的显色反应,其灵敏度较高,摩尔吸光系数ε为2.46×104。采用掩蔽方法,能显著提高体系的选择性。用拟定的方法测定了铜矿中的铜,结果令人满意。  相似文献   

20.
4,5-二氢-3-甲基-1-(4-氯-2-氟苯基)-4-二氟甲基-1,2,4-三唑-5(1H)酮是超高效含氟除草剂唑酮草酯的重要中间体,采用高温氟化的方法,通过优化反应条件,使目标化合物的合成收率达75.4%,含量达97.3%,降低了成本,更利于工业化生产.  相似文献   

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