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三甲氧基苄啶分子印迹整体柱的制备及色谱性能 总被引:2,自引:0,他引:2
选择甲基丙烯酸为功能单体\, 甲基丙烯酸乙二醇双酯为交联剂, 制备了三甲氧基苄啶分子印迹整体柱, 对整体柱材料的形貌进行了表征, 并且研究了TMP和5种磺胺类药物在分子印迹整体柱上的色谱行为. 相似文献
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以2-(2-硝基苯基)乙腈及4,6-二甲氧基-2-甲磺酰基嘧啶为起始原料,分别经缩合、还原及酰胺化反应合成了6个未见文献报道的N-(2-(腈基(4,6-二甲氧基嘧啶-2-基)甲基)苯基)酰胺类衍生物,其结构经1H NMR、MS和元素分析进行了确证。 在150 g/hm2的用量条件下,合成化合物未显示出除草活性。 在200 mg/L浓度下,部分化合物对黄瓜灰霉病及水稻纹枯病表现出一定的抑菌作用,其中化合物4d对水稻纹枯病的抑制率为72.33%。 相似文献
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噻唑并嘧啶类化合物的合成研究进展 总被引:2,自引:0,他引:2
综述了在医药和农药领域具有广泛用途的噻唑并嘧啶类化合物近二十年来合成方法上的研究进展. 结合本研究组在这一领域的工作介绍了噻唑并嘧啶类化合物的三种主要结构类型: 噻唑并[3,2-a]嘧啶、噻唑并[4,5-d]嘧啶、噻唑并[5,4-d]嘧啶类化合物的相关合成方法及新进展. 相似文献
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4,6-二甲氧基-2-嘧啶重氮氨基偶氮苯的合成及其与汞(Ⅱ)的显色反应 总被引:5,自引:1,他引:4
合成了4,6-二甲氧基-2-嘧啶重氮氨基偶氮苯(DMPDAA),并研究了它与汞(Ⅱ)的显色反应。结果表明,在TritonX-100存在下,于pH 10.5 Na2B4O7-NaOH缓冲体系中,Hg(Ⅱ)与4,6-二甲氧基-2-嘧啶重氮氨基偶氮苯形成1∶4的红色配合物,其最大吸收波长位于522 nm,表观摩尔吸光系数为1.52×105L.mol-1.cm-1。Hg(Ⅱ)在0~0.80μg/mL范围内符合比尔定律。方法已用于水样中汞的测定。 相似文献
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探讨了在微波加热条件下,芳香醛、取代苯乙酮和尿素的三组分反应在N,N-二甲基甲酰胺(DMF)中制得4,6-二芳基-3,4-二氢嘧啶-2(1H)-酮类化合物,收率为68%~84%.若在反应体系中加入三甲基氯硅烷,该三组分反应则高产率(66%~87%)地生成相应的脱氢产物4,6-二芳基嘧啶-2(1H)-酮类化合物.该反应具有反应条件温和、产物收率高、操作方便等优点,为4,6-二芳基-嘧啶-2(1H)-酮类药物中间体的合成提供了一条全新的路线. 相似文献
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以羰基衍生物,取代1,3-二羰基化合物,脲和硫脲为原料,经固定化青霉素酰化酶催化的Biginelli反应合成了22个四氢嘧啶类化合物(1a~1v),其中1s和1v为新化合物,其结构经1H NMR, 13C NHR和IR表征。研究了溶剂、反应温度、反应时间和物料比γ[n(苯甲醛) :n(脲) :n(乙酰乙酸乙酯)]对1a产率的影响。结果表明:在最佳反应条件(固定化青霉素酰化酶为催化剂,乙醇为溶剂,γ=1.0 :1.5:1.0,于50 ℃反应6 h)下,1a产率最高(85%)。 相似文献
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Flavansrefertoalargegroupofnaturallyoccurringcompoundspossessinga2-phenyl-chromannucleus.Naturallyoccurringflavansexhibitanumberofimportantbiologicalactivitieswhichifexploitedproperly,mayleadtovaluablenewdrugsoragrochemicals'.Inflavansynthesis,thekeystepistoconstructthe3,4-dihydrobenzopyranring-Variousmethodshavebeendevelopedfortheringformation,butmostoftheminvolvemultiplestepsandgivelowoverallyields2.Inthispaper,BF3wasusedforthefirsttimeasanefficientcatalysttoformthepyranringfroml,3-diaryIp… 相似文献
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An unprecedented protocol has been developed for the efficient synthesis of substituted tetrahydropyrans via a bismuth‐promoted Prins cyclization of imines with homoallyl alcohols. In the presence of 40 mol% BiCl3, a wide variety of imines react smoothly with homoallyl alcohols at room temperature to give the corresponding 4‐chlorotetrahydropyran derivatives in good to excellent yields. 相似文献
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《Analytical letters》2012,45(11):967-973
Abstract A sensitive HPLC method for the quantitation of trimethoprim in plasma and urine was developed using fluorescence detection. Plasma (or urine) samples were made basic by the addition of 3.8N sodium hydroxide and extracted with chloroform:2-propanol (95:5). After evaporation of the organic layer, a portion of the residue was analyzed by HPLC with fluorescence detection. The minimum detectable quantity is 0.1 μg/ml for this method. This method has been applied to the analysis of plasma and urine obtained from subjects after a single 160 mg dose of trimethoprim. 相似文献
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Chung-Yin Lin Subrata Chakraborty Chia-Wei Wong Dar-Fu Tai 《Molecules (Basel, Switzerland)》2021,26(2)
The present investigation reports an attempt to synthesize naturally occurring α-cyclic tripeptide cyclo(Gly-l-Pro-l-Glu) 1, [cyclo(GPE)], previously isolated from the Ruegeria strain of bacteria with marine sponge Suberites domuncula. Three linear precursors, Boc-GPE(OBn)2, Boc-PE(OBn)G and Boc-E(OBn)GP, were synthesized using a solution phase peptide coupling protocol. Although cyclo(GPE) 1 was our original target, all precursors were dimerized and cyclized at 0 °C with high dilution to form corresponding α-cyclic hexapeptide, cyclo(GPE(OBn))2 7, which was then converted to cyclic hexapeptide cyclo(GPE)2 2. Cyclization at higher temperature induced racemization and gave cyclic tripeptide cyclo(GPDE(OBn)) 9. Structure characteristics of the newly synthesized cyclopeptides were determined using 1H-NMR, 13C-NMR and high-resolution mass spectrometry. The chemical shift values of carbonyls of 2 and 7 are larger than 170 ppm, indicating the formation of a cyclic hexapeptide. 相似文献
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Chayanika Kashyap Siddhartha K. Purkayastha Shahnaz S. Rohman Dr. Ankur K. Guha 《Chemphyschem》2023,24(5):e202200504
The scope of Bergman cyclization is expanded computationally by exploring the cyclization in inorganic B, N substituted derivative. This substitution has introduced polarity into the transition state, which resulted in dramatic lowering of the activation barrier. Natural charge distribution throughout the reaction profile has ascertained this hypothesis. Single B and N atom substitution at 1 and 6 terminal positions lowers the activation barrier by almost half of the original value which becomes even lower in the complete B, N analogue. The parent Bergman and single B, N substituted products were characterized by significant biradical character while the complete B, N substituted analogue was characterized by significant zwitterionic character. Reduction in electron delocalization is also observed in the complete B, N substituted analogue. 相似文献
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Competitive Silyl–Prins Cyclization versus Tandem Sakurai–Prins Cyclization: An Interesting Substitution Effect 下载免费PDF全文
Alberto Diez‐Varga Héctor Barbero Prof. Dr. Francisco J. Pulido Dr. Alfonso González‐Ortega Prof. Dr. Asunción Barbero 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(43):14112-14119
Two different mechanism pathways are observed for the reaction of allylsilyl alcohols 1 and aldehydes in the presence of trimethylsilyl trifluoromethanesulfonate (TMSOTf). In the case of allylsilyl alcohols without allylic substituents, the reaction gives dioxaspirodecanes, which are the products of a tandem Sakurai–Prins cyclization. In contrast, allylsilyl alcohols with an allylic substituent (R2≠H) selectively provide oxepanes, thus corresponding to a direct silyl–Prins cyclization. Both types of product are obtained with excellent stereoselectivity. Theoretical studies have been performed to obtain some rationalization for the observed stereoselectivity. 相似文献
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JinHuiYANG WeiDongZ.LI 《中国化学快报》2005,16(4):433-436
An effective approach for the construction of the decalin ring skeleton of labdane diterpenoids was developed based on a key biomimetic cationic polyene cyclization of an epoxy allylsilane precursor. The synthetic approach demonstrated here would be useful in the enantioselective and diastereoselective total synthesis of natural labdane diterpenoids in general. 相似文献
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Severin Eder Manuel Torko Alessia Montalbetti Paride Azzari Laura Nystrm 《Molecules (Basel, Switzerland)》2021,26(11)
The pace of industrialization and rapid population growth in countries such as India entail an increased input of industrial and sanitary organic micropollutants, the so-called emerging contaminants (EC), into the environment. The emission of EC, such as pharmaceuticals, reaching Indian water bodies causes a detrimental effect on aquatic life and ultimately on human health. However, the financial burden of expanding sophisticated water treatment capacities renders complementary, cost-efficient alternatives, such as adsorption, attractive. Here we show the merits of washed and milled pigeon pea husk (PPH) as low-cost adsorbent for the removal of the EC trimethoprim (TMP) and atenolol (ATN) that are among the most detected pharmaceuticals in Indian waters. We found a linear increase in adsorption capacity of PPH for TMP and ATN at concentrations ranging from 10 to 200 μg/L and from 50 to 400 μg/L, respectively, reflecting the concentrations occurring in Indian water bodies. Investigation of adsorption kinetics using the external mass transfer model (EMTM) revealed that film diffusion resistance governed the adsorption process of TMP or ATN onto PPH. Moreover, analysis of the adsorption performance of PPH across an extensive range of pH and temperature illustrated that the highest adsorption loadings achieved concurred with actual conditions of Indian waters. We anticipate our work as starting point towards the development of a feasible adsorbent system aiming at low-cost water treatment. 相似文献
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This paper reports on the synthesis, characterization and electrochemical performance of LiV3O8 nanorods which were prepared through a very facile hydrothermal route. The diameters of the LiV3O8 nanorods are about 150 nm. The morphology of LiV3O8 can be controlled by adjusting the reaction conditions such as the reaction time and temperature. Electrochemical measurements reveal that the as‐prepared LiV3O8 nanorods display high initial discharge capacities (292.5 mA·hg?1) and excellent cyclability. This result indicates that the nanorods are a promising cathode candidate material for lithium batteries. 相似文献