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1.
以3-[邻(或对)羧苯胺基]-4-羟基-3-环丁烯二酮(1a, 1b)为底物,与一些磺胺反应, 成功地制得了14个新的不对称取代的异方酰胺。3a~3f和4a~4f结构上的共同特点是, 有药物作用的磺酰胺和邻(或对)氨基苯甲酸的结构单元, 通过方酸四碳环的桥接作用而共存于同一分子之中。  相似文献   

2.
两种钨硼杂多酸的合成和性质研究   总被引:5,自引:0,他引:5  
本文报道了两种钨硼酸的最佳合成条件:在较高的pH,稍过量的硼酸和较低温度下有利于六方酸的生成;在较低的pH,大量过量的硼酸和较高温度时则利于生成四方酸,合成这两种酸的方法较文献优越,测得六方酸的UV,IR和RAMAN光谱性质,并 对其结构进行初步探讨。  相似文献   

3.
N-芳基氮氧方酸(3-芳胺基-4-羟基-3-环丁烯二酮)是合成不对称方酸衍生物的关键中间体之一,开展了对其合成方法的研究,发现并实现了方酸与芳伯胺在水中的脱水反应,制得17个N-芳基氮氧方酸3a~3q,其中N-8'-喹啉基氮氧方酸(3q)具有热致变色性质,根据实验事实,提出了可能的反应历程。该合成方法产率较高,产物易于分离纯化,是制备N-芳基氮氧方酸简便有效的好方法。  相似文献   

4.
方酸菁染料的合成   总被引:2,自引:0,他引:2  
蒋松春  范如霖  朱正华 《化学学报》1986,44(11):1182-1184
方酸菁染料业经证明具有光谱增感作用,但迄今未见其作为照相材料应用的报道.1973年法国Siegfried等将其用于巨脉冲红宝石激光的无源切换;最近Morel等又研究了它们在太阳能电池中的应用.作者合成了八个方酸菁染料,并对它们的照相性能和光电转换特性作了初步研究;发现其中的个别化合物不但具有良好的光谱增感作用,而且与照相工业中常用的染料“1833”相比,衰退也比较慢;部分化合物还表现出相当高的光电转换效率. 作者曾报道方酸的合成.本文介绍另一种方法,即以醋酸钠-醋酸环化1,1,3-三氯-2,  相似文献   

5.
并入两个四氢键组装单体的卟啉衍生物的合成研究   总被引:1,自引:0,他引:1  
报道了一个新的卟啉四氢键超分子聚合物组装单体29的合成研究。通过对 Gong等最近报道的四氢键二聚体组装板块进行修饰,合成了两个相应的新的苯甲酸 衍生物中间体11和21,以间-硝基苯甲醛为原料以较高产率合成了一个二硝基四苯 基卟啉26,氯化亚锡还原得到另-卟啉二胺中间体28。以DCC为缩合剂,该卟啉二 胺与其中一个酸11发生缩合反应得到相应卟啉组装单体目标分子29。化合物29在弱 极性溶剂中具有良好的溶解度。  相似文献   

6.
合成了两个新型方酸菁染料3和5。在催化下,2,3,3-三甲基假吲哚不需N- 烷基化,可直接与方酸反应。反应过程中发生了明显的质子转移。结晶学数据表明,分子3的整体位于同一平面;溶剂苯规则地排在方酸四碳的周围, 后者酷似电子陷肼。染料5有良好的水溶性。  相似文献   

7.
合成了两个新型方酸菁染料3和5。在催化下,2,3,3-三甲基假吲哚不需N- 烷基化,可直接与方酸反应。反应过程中发生了明显的质子转移。结晶学数据表明,分子3的整体位于同一平面;溶剂苯规则地排在方酸四碳的周围, 后者酷似电子陷肼。染料5有良好的水溶性。  相似文献   

8.
新型光学活性α-氨基磷酸及其酯合成进展   总被引:3,自引:1,他引:3  
α-氨基膦酸酯是一类很重要的天然氨基酸类似物,具有新颖的化学结构和多 种生理活性。综述了近年来光学活性α-氨基膦酸及酯的合成进展。  相似文献   

9.
方酸及方酸内鎓盐   总被引:8,自引:1,他引:7  
本文介绍并评述方酸及方酸内翁盐的化学现状。着重介绍了我国方酸研究的情况。根据我们所观察到的某些化学现象,结合所收集与测定的光谱数据及四圆单晶衍射图谱等,对方酸及方酸内翁盐的结构与反应性能提出了一些看法与解释。  相似文献   

10.
将具有造影功能的泛影酸酰化得泛影酰氯,泛影酰氯与靶向性药物磺胺嘧啶钠合成得泛影磺胺嘧啶N-2-(嘧啶基)-N-[3,5-二-(N-乙酰胺基)-2,4,6-三碘]苯甲酰基}对氨基苯磺酰胺]。其结构经UV,NMR和IR表征。  相似文献   

11.
A number of new Schiff's bases of gossypol with aromatic amines and sulfanilamide compounds has been obtained. It has been shown by UV and PMR spectroscopy and x-ray structural analysis that in some solvents they exist predominantly in the quinoid form. For dianilinegossypol (in the solid state) the quinoid structure has been demonstrated and two polymorphic modifications have been revealed by x-ray structural analysis.A. S. Sadykov Institute of Bioorganic Chemistry, Uzbek SSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 650–654, September–October, 1988.  相似文献   

12.
The present report describes the X‐ray structural and theoretical studies of some new pinacolboronate esters, and it also outlines the use of the target structures in Suzuki coupling reactions to produce new aromatic or heteroaromatic esters and amides. X‐ray structural analysis of the studied compounds revealed that the pinacolborane ring's position with respect to the benzene ring varies, depending on the particular environment. An ortho‐positioned carboxylic ester (methyl ester) causes a nearly perpendicular orientation of the pinacolborane unit with respect to the benzene ring, whereas an ortho‐positioned amide (N,N‐dimethylamide) causes the pinacolborane unit to orient itself nearly coplanar. A plausible explanation has been provided, based on both steric and electronic factors.  相似文献   

13.
It has been shown that amino derivatives of sulfanilamide, and also some functionally substituted primary arylamines and cycloalkylamines, undergo heterocyclization with triethyl orthoformate and sodium azide with the formation of 1-monosubstituted tetrazoles. Primary amines of the azole series, 5-aminotetrazole, 5-amino-1-methyltetrazole, 4-amino-1,2,4-triazole, and also less basic arylamines (4-fluoro-3-nitroaniline, 2,6-dibromo-4-nitroaniline) did not react. An efficient method of introducing an amino group into position C(5) of the tetrazole ring of 1-aryltetrazoles is proposed, based on alkaline decomposition of the tetrazole ring and heterocyclization of the resulting N-arylcyanamides on interaction with ammonium azide generated in situ. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1174–1179, August, 2005.  相似文献   

14.
Sulfanilamide belongs to the group of drugs that have a bacteriostatic effect on different pathogenic microorganisms. This activity originates from the competitive antagonism with p-aminobenzoic acid, which is an integral part of folic acid. The safe use of sulfanilamide is limited due to poor solubility in the aqueous medium. Therefore, the aim of this paper is the synthesis of sulfanilamide, as well as preparing and structural characterization of its inclusion complexes with cyclodextrins. The crude sulfanilamide was obtained in the synthesis between acetanilide and chlorosulfonic acid according to the standard procedure. The synthesized sulfanilamide was recrystallized from water in order to obtain the satisfactory purity of the substance. Sufanilamide was complexed with β-cyclodextrin and 2-hydroxypropyl-β-cyclodextrin by the co-precipitation method. A molecular encapsulation of sulfanilamide was confirmed by using FTIR, 1H-NMR, XRD and DSC methods. Phase-solubility techniques were used to assess the formation of the inclusion complex between sulfanilamide and cyclodextrins. The photostability of sulfanilamide and its inclusion complexes was estimated by UVB irradiation in a photochemical reactor by applying the UV–Vis method. Based on the UV–Vis analysis, sulfanilamide:2-hydroxypropyl-β-cyclodextrin complex was presented as more photostable than sulfanilamide:β-cyclodextrin complex and sulfanilamide. The obtained results enable the potential use of these inclusion complexes for the preparation of oral formulations due to the enhanced solubility of sulfanilamide.  相似文献   

15.
杜海堂 《化学通报》2019,82(9):831-836,854
为寻找具有杀菌活性的三唑类先导化合物,采用活性亚结构拼接方法,将香豆素环和硫醚结构单元引入到三唑类化合物分子中,合成一系列未见文献报道的新型含香豆素环和硫醚结构的三唑类衍生物。经~1H NMR、~(13)C NMR、IR、MS和元素分析对所合成化合物的结构进行了表征。初步生物活性测试表明,部分目标化合物在试验浓度下具有一定的抑菌活性。  相似文献   

16.
Abstract— Ultraviolet light (A > 295 nm) induced binding of sulfanilamide to cellular macromoleculcs has been examined. It was found that the drug bound irreversibly to native DNA, and complexes containing one drug molecule per 80 nucleotides were obtained after 60 min of irradiation under anaerobic conditions. Oxygen reduced this binding significantly. More drug was bound to RNA and heat denatured DNA under identical conditions. The binding of sulfanilamide to DNA was found to induce nicking of circular closed plasmid DNA and cross-linking of calf thymus DNA. Oxygen significantly decreased nicking and cross-linking of DNA. Irradiation of sulfanilamide and human serum albumin resulted in covalent binding of the drug to the protein and a concomitant increase in protein crosslink-ing. While oxygen decreased covalent binding, crosslinking increased under aerobic conditions. These reactions may be important in the photosensitization caused by sulfanilamide.  相似文献   

17.
A procedure for rapid quantitative analysis of pharmaceutical powders is described. Powdered samples were measured in a rotating cell in order to avoid sub-sampling problems by increasing the irradiated area. Quantitative determination of sulfathiazole and sulfanilamide, using a simple univariate calibration model is proposed. Even though both antibacterials are of the same chemical family (sulfonamides), the richness of structural information contained in the Raman spectra allowed their determination using the area of two selected bands (1255 and 1629 cm−1 for sulfathiazole and sulfanilamide, respectively). Relative standard deviation (R.S.D.) values (n = 10) of 3.35% and 3.46% for sulfathiazole and sulfanilamide, respectively, demonstrate the good reproducibility of the measurement technique with the rotating cell. The method was successfully applied to the analysis of synthetic mixtures and commercial pharmaceutical powders. The procedure is suitable to be applied to pharmacopoeial uniformity of content testing of batches.  相似文献   

18.
The syntheses of new aromatic 30pi heptaphyrins either through a [5 + 2] or a [4 + 3] acid-catalyzed condensation and oxidative coupling reactions of easily available and air-stable precursors are reported. The methodology followed is not only simple and efficient but also allows synthesis of a range of heptaphyrins with different heteroatoms in the core. The oxidative coupling reactions of modified tripyrranes 11 and tetrapyrranes 12 were found to be dependent on the acid concentration used and as well as the substituents present on the meso position. The change of meso aryl substituents in 11 and 12 to meso mesityl substituents gave a new heptaphyrin 18. The structural characterization has been done with extensive 1H and 2D NMR studies. The heptaphyrins reported here show rich structural diversity when the connections of the heterocyclic rings are altered, and accordingly, one ring and two ring inversions have been observed. By a judicious choice of the precursors it has been possible to control the site of ring inversion either in the bithiophene unit or in the tripyrrane unit. Theoretical calculations performed on three different heptaphyrins, 4, 5, and 17, also reveal that the inverted structures are approximately 35-40 kJ lower in energy relative to the corresponding noninverted structures. Furthermore, one of the heptaphyrins 10c shows the presence of two conformers in solution in the ratio 1:2 and no interconversion between the conformers have been observed in the temperature range of 343-228 K. On protonation, the aromaticity and the ring inversions are retained and the deltadelta values vary in the range 10.07-20.59 ppm. The energies of the Soret maxima and the HOMO-LUMO gap vary linearly with the increase in pi electrons further justifying the aromatic nature of the heptaphyrins.  相似文献   

19.
A new spectrophotometric method for the assay of very small amounts of chloramine-T has been developed using sulfanilamide. This method is simple and accurate within the limits described.  相似文献   

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