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1.
本文提供了新显色剂3,5-二溴-4-偶氮变色酸苯基荧光酮的合成方法,研究了试剂与铜(Ⅵ)的分光光度性质及反应条件,在盐酸介质中及表面活性剂CTMAB存在下,试剂与钼(Ⅵ)形成红色胶束配合物,在542nm处有最大吸收,表观摩尔吸光系数为1.68×10 ̄5L·mol ̄-1·L ̄-1,铜(Ⅵ)含量在0~10μg/25mL范围内符合比尔定律,大多数常见金属元素的存在不干扰铜的测定,拟定方法用于铜样中微量钼的测定,结果满意。  相似文献   

2.
An efficient method for the synthesis of novel pyrido[3',2':4',5']thieno[3',2':2,3]pyrido [4,5:d][1,3]thiazolo[3,2-a]pyrimidine-4-one derivatives (5) has been developed using a Pictet-Spengler reaction between 2-(3-aminothieno[2,3-b]pyridin-2-yl)thiazolo[3,2-a] pyrimidin-5-one (3), which could be obtained from the condensation of 7-(chloromethyl)-5H-thiazolo[3,2-a]pyrimidin-5-one (1) with 3-cyanopyridine-2-thione (2) via Thorpe-Ziegler isomerization, and aromatic aldehydes under NH2SO3H as catalysis in good yields.  相似文献   

3.
黄酮类化合物广泛存在于埴物体中,具有广泛的生物活性,其研究发展很快,但对于氮杂黄酮类化合物的研究工作却甚少。含氮黄酮类化合物具有抗癌、抗菌、冠状动脉扩张等作用。但是,目前黄酮类药物仍存在以下问题:(1)黄酮类化合物结构繁多,生物活性极其广泛,但作用强度普遍较弱;(2)黄酮类化合物水溶性较低,影响药物的吸收与疗效。新型黄酮类化合物的合成仍有一定的意义。  相似文献   

4.
From the hexane extractive of the nutmeg of Myristica fragrans Houtt, glyceryl trimyristate (1), myristicin (11), methyleugenol (12), elemicin (13), dehydrodiisoeugenol (9), 1-(3,4,5-trimethoxyphenyl)-2-(4-allyl-2,6-dimethoxyphenoxy)-propan-1-ol (4), 1-(3,4-methylenedioxyphenyl)-2-(4-allyl-2,6-dimethoxyphenoxy)-propan-1-ol (6), and a new compound 1-(3,4-dimethoxyphenyl)-2-(4-allyl-2,6-dimethoxyphenoxy) propan-1-ol (14) were isolated. The structure of compound (14) was determined to be an analogue of the β-0-4 ether type of dilignols.  相似文献   

5.
报道从中国南海网胰藻Hydroclathrus clathratus中分离得到3个单体化合物,经过MS,IR,1HNMR,13CNMR(DEPT),HMQC和HMBC等波谱技术鉴定为:(6R,7aS)-6-羟基-4,4,7a-三甲基-2,4,5,6,7,7a-六氢苯并呋喃-2-酮(1),1-(2-脱氧-β-D-呋喃核糖)-5-甲基-1,2,3,4-四氢嘧啶-2,4-二酮(2),尿嘧啶(3),并通过X射线单晶衍射实验确定化合物1的立体结构,其中化合物1是首次从自然界中分离得到.  相似文献   

6.
New pyrazolo[1,5-a]quinazoline-3-carbonitriles 4a,b were obtained via cyclocondensation of 5-amino-3-cyanomethyl-1H-pyrazole-4-carbonitrile (1) with enaminones of 1,3-cyclohexanedione derivatives 2a,b in refluxing glacial acetic acid. Condensation of compounds 4a,b with various aromatic aldehydes furnished the corresponding arylidene derivatives 6a–j. On the other hand, condensation of 4a,b with o-hydroxybenzaldehydes yielded the polyheterocyclic compounds 10a–h. Coupling of compounds 4a,b with aryldiazonium chlorides led to formation of 2-arylhydrazono derivatives 12a–h. Also, reaction of compounds 4a,b with phenyl isothiocyanate, followed by addition of ethyl chloroacetate and chloroacetonitrile, afforded the polyheterocyclic compounds based on pyrazolo[1,5-a]quinazoline core. The reaction of compounds 4a,b with phenyl isothiocyanate and elemental sulfur gave the thiazole-2-thione derivatives 25a,b. The reaction of enamines of compounds 4a,b with each of hydrazine hydrate and guanidine hydrochloride afforded pyrazolo[4″,3″:5′,6′]pyrido[4′,3′:3,4]pyrazolo[1,5-a]quinazolin-8-ones 30a,b and pyrimido[5″,4″:5′,6′]pyrido[4′,3′:3,4]pyrazolo[1,5-a]quinazolin-9(10H)-ones 33a,b, respectively. The structures of all the newly synthesized compounds were elucidated by elemental analyses and spectral data. The plausible mechanisms have been postulated to account for their formation.  相似文献   

7.
Coupling the diazonium salt of 3-amino-2-cyano-4,6-dimethylthieno[2,3-b]pyridine 1 with malononitrile 2 gave 2-cyano-3-(hydrazonomalononitrile)-4,6-dimethylthieno[2,3-b]pyridine 3 which then reacted with hydrazine compounds 4a-4h to yield corresponding 2-cyano-3-(3,5-diamino-1-substituted-pyrazol-4-yl)azo-4,6-dimethylthieno[2,3-b]pyridines 5a-5h. The 2-cyano-3-(2-amino-5,7-disubstituted-pyrazolo-[1,5-a]pyrimidine-3-yl)azo-4,6-dimethylthieno[2,3-b]pyridines 7a-7f were obtained in good yield by the cyclocondensation reaction of 2-cyano-3-(3,5-diamino-pyrazol-4-yl)azo-4,6-dimethylthieno[2,3-b]pyridine 5a with the appropriate 1,3-diketones 6a-6f under acidic condition.  相似文献   

8.
New 5-hydroxymethyl-8-methyl-3-(3-aryl-[1,2,4]oxadiazol-5-yl)-2H-pyrano-[2,3-c]pyridin-2-ones and their esters were synthesized. The structure of obtained compounds was determined through a complete 1H NMR analysis.  相似文献   

9.
The role of metalloenzymes in tumor progression had broadened their application in cancer therapy. Of these, MMPs and CAs are validated druggable targets that share some pivotal signaling pathways. The majority of MMPs or CAs inhibitors are designed as single-target agents. Despite their transient efficacy, these agents are often susceptible to resistance. This set the stage to introduce dual inhibitors of correlated MMPs and CAs. The next step is expected to target the common vital signaling nodes as well. In this regard, VEGFR-2 is central to various tumorigenesis events involving both families, especially MMP-2 and CA II. Herein, we report simultaneous inhibition of MMP-2, CA II, and VEGFR-2 via rationally designed hybrid 1,2,4-triazolo[4,3-a]pyrimidinone acyclo C-nucleosides. The promising derivatives were nanomolar inhibitors of VEGFR-2 (8; IC50 = 5.89 nM, 9; IC50 = 10.52 nM) and MMP-2 (8; IC50 = 17.44 nM, 9; IC50 = 30.93 nM) and submicromolar inhibitors of CA II (8; IC50 = 0.21 µM, 9; IC50 = 0.36 µM). Docking studies predicted their binding modes into the enzyme active sites and the structural determinants of activity regarding substitution and regioselectivity. MTT assay demonstrated that both compounds were 12 folds safer than doxorubicin with superior anticancer activities against three human cancers recording single-digit nanomolar IC50, thus echoing their enzymatic activities. Up to our knowledge, this study introduces the first in class triazolopyrimidinone acyclo C-nucleosides VEGFR-2/MMP-2/CA II inhibitors that deserve further investigation.  相似文献   

10.
A new coordination polymer,[Mn(L)(1,4-bdc)] (L=11-fluoro-dipyrido[3,2-a:2,3-c]phenazine,1,4-bdc=benzene-1,4-dicarboxylate),has been synthesized through the hydrothermal method and characterized by elemental analysis,IR and single-crystal X-ray diffraction.It crystalli-zes in triclinic,space group P1 with a=9.7544(9),b=10.8254(10),c=11.5288(10),α=114.1300(10),β=96.6110(10),γ=105.0390(10)°,V=1038.62(16)3,Z=2,C 26 H 13 FMnN 4 O 4,M r=519.34,D c=1.661 g/cm 3,F(000)=526,μ(MoKa)=0.691 mm-1,R=0.0405 and wR=0.0977.The 1,4-bdc dianions link the neighboring Mn(II) atoms to yield a two-dimensional layer structure.The L ligands are attached on both sides of the layer.The π-π interactions between the L ligands of neighboring layers result in a three-dimensional supramolecular architecture.  相似文献   

11.
A New Chromone Derivative from Stellera chamaejasme L.   总被引:3,自引:0,他引:3  
A new chromone derivative,3-[1-(2,4,6-trihydroxyphenyl)3-di-(4-hydroxyphenyl) 1-propanone-2-yl]5,7-dihydroxy-8-di(4-hydroxyphenyl)methyl-4H-1-benzopyran-4-one,named as isomohsenone was isolated from the roots of Stellera chamaejasme L.together with known chamaechromone. Its structure was determined by the analysis of MS and NMR data,especially 2D NMR spectra.  相似文献   

12.
以3-芳基-5-巯基-1,2,4-三唑为原料合成了20个3-芳基-1,2,4-三唑-5-巯基乙酸乙酯(2a~e)、3-芳基-1,2,4-三唑-5-巯基乙酸(3a~e)、3-芳基-5,6-二氢噻唑并[2,3-c]均三唑(5a~e)和3-芳基-6,7-二氢均三唑并[3,4-b][1,3]噻嗪(6a~e)。研究了3a~e在微波辐射下的环化反应,合成了5个3-芳基-5-氧代-6H-噻唑[2,3-c]均三唑(4a~e)。产物经元素分析、红外、核磁共振以及质谱方法确定了结构。初步研究了代表化合物的生物活性。  相似文献   

13.
A new facile route for synthesis of 3-(aryl)-8,9-diphenylfuro[3,2-e][1,2,4]triazolo pyrimidines derivative from the same starting material, 2-amino-4,5-diphenylfuran-3-carbonitrile, has been developed through heterocyclization of the corresponding arylidene-hydrazono-5,6-diphenylfuro[2,3-d]pyrimidine and N-(arylmethylene)-4-imino-5,6-diphenylfuro[2,3-d]pyrimidin-3(4H)-amine under refluxing condition with acetic anhydride followed by air oxidation. The products were obtained in good yield with an easy workup along with the purification of products by a nonchromatographic method. This general synthetic procedure can be extended to the preparation of a wide range of isomeric triazoles using 2-amino 3-carbonitrile bifunctional derivatives.  相似文献   

14.
提出以三氟乙酸酐作为衍生化试剂,将核黄素半合成中问体N-(D)-脱氧核糖醇基-3,4-二甲苯胺(Ⅰ)及4,5-二甲基-N-(D)-脱氧核糖醇基-2-偶氮苯基苯胺(Ⅱ)转化为低沸点易汽化物质,采用以苯乙酮作内标,测定中间体(Ⅰ)和(Ⅱ)纯度的气相色谱法.方法具有分析速度快、准确度高、重现性好等优点,方法回收率(Ⅰ)为96.9%~101.2%、(Ⅱ)为99.4%~100.4%,相对标准偏差(Ⅰ)在4.4%、(Ⅱ)在2.6%以内.  相似文献   

15.
设计并合成了5种呋喃并[3’,4’:5,6]吡啶并[2,3-c]吡唑受体分子, 利用紫外-可见吸收光谱考察了其与F-, Cl-, Br-, AcO-, 等阴离子的作用. 结果表明该类受体分子与阴离子形成氢键配合物, 导致呋喃并吡啶并吡唑受体的光谱发生变化. 测定了配合物的结合比和稳定常数, 发现受体化合物对F-, AcO-离子具有良好的选择性, 对其它多种阴离子无影响. Job曲线表明受体分子与阴离子间形成1∶1型的配合物.  相似文献   

16.
在酸性介质中,Pt(Ⅳ)对溴酸钾氧化DBS-偶氮氯膦的褪色反应有明显的催化作用,确定了最佳反应条件,建立了微量铂的催化分光光度法,测定铂的线性范围在0.10~3.0μg/10ml之间。用于精矿和二次阳极泥中铂的测定,结果满意。  相似文献   

17.
Various 3,10-disubstituted-bis-1,2,4-triazolo[4,3-a][3′,4′-c]quinoxalines (4) have been synthesized in a facile and efficient manner by copper dichloride mediated oxidative intramolecular cyclization of bis-arylidene derivatives of 2,3-dihydrazinoquinoxaline (3).  相似文献   

18.
使用硫杂冠醚、穴醚[2.2.2]作气相色谱固定相制备毛细管柱,考察两种固定相的使用比例、极性、热稳定性,并对甲苯-苯、乙苯-甲苯、甲基苯酚(o/p)、二氯苯(o/p,m)、硝基氯化苯(m,o)、苯-环己烷、庚醇-辛醇、苯胺-N,N二甲基苯胺等混合样品进行色谱分离.实验结果表明:两种固定相在OV-1701中的比例均为15%时有较好的分离效果,都属于中等极性的固定相.硫杂冠醚、穴醚[2.2.2]的平均极性分别为815、832,其中硫杂冠醚固定相的热稳定性较好,有较高的使用温度(185℃),而穴醚[2.2.2]的最高使用温度为120℃,因此穴醚[2.2.2]的使用温度受到一定的限制.从它们较好的分离性能看,固定相硫杂冠醚、穴醚[2.2.2]均具有较好的应用前景.  相似文献   

19.
Coloradocin, a novel macrolide antibiotic from cultures of Actinoplanes coloradoensis1exhibits activity against pathogenic anaerobic and microaerophilic species2. Because itslow toxicity and substantial oral activity3, , as well as its unusual structure5, several 4research groups initiated approaches towards the synthesis of coloradocin6, whichculminated in the synthesis of 18-deoxynargenicin A1 by Kallmerten et al.7. …  相似文献   

20.
The crystal structure of the title compound 1-(4-fluorophenyl) -2-hexylthio-benzo [4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a]pyrimidin-5(1H) -one(C23H21FN4O2S,Mr = 436.5) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic,space group P21/n with a = 13.9854(3) ,b = 17.2678(4) ,c = 18.1828(5) ,β = 99.364(2) °,V = 4332.58(18) 3,Z = 4,Dc = 1.338,F(000) =1824,μ = 0.185 mm-1,MoKa radiation(λ = 0.71073) ,R = 0.0538 and wR = 0.1162 for 4728 observed reflections with I > 2σ(I) . X-ray diffraction analysis reveals the fused rings of benzo[4,5]furo[3,2-d]-1,2,4-triazolo[1,5-a] pyrimidin-5(1H) -one system are nearly coplanar. The crystal packing is mainly stabilized by weak intermolecular C-H···O hydrogen bond and π-π interactions.  相似文献   

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