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1.
杨丕鹏  段文贵 《有机化学》1991,11(6):620-623
取代芳杂环及其苯并物在溶液中的互变异构平衡实验结果已有大量报道。互变异构体的芳性或共振能(RE)被广泛用于定性解释互变平衡的移动趋向,Katritzky 等并从互变平衡实验数据得出吡啶酮、喹诺酮和异喹诺  相似文献   

2.
根据拼合原理, 设计并合成了21个未见报道的新的二芳醚基哌嗪类衍生物, 其结构用1H NMR, ESI-MS, HRMS进行了确证, 初步生物活性测定实验证明部分目标化合物具有良好的细胞毒活性. 化合物4i分别对人食管癌(Eca109)细胞株和人鼻咽癌(CNE)细胞株的IC50为7.13和4.54 μmol•L-1, 与对照品顺铂(DDP)相近. 化合物5d对人鼻咽癌细胞株也表现较好的活性, 其IC50为8.49 μmol•L-1.  相似文献   

3.
Synthesis of selectively substituted fluorenes and fluorenols was achieved by using catalytic [2+2+2]cyclotrimerization. Various starting diynes were reacted with different alkynes in the presence of a catalytic amount of Wilkinson’s catalyst (RhCl(PPh3)3) providing the compounds possessing the fluorene scaffold in good isolated yields. A set of four regioselectively substituted fluorenols was converted to the corresponding 9,9′‐spirobifluorenes and their spectral characteristics were measured.  相似文献   

4.
3-Ethyl 2-amino-4-methyl-5-phenyl thiophene carboxylate 1 was used as a starting material to synthesize 2a,b via coupling with malononitrile or acetyl acetone, respectively. When heated, under reflux in sodium ethoxide solution, 2a,b give 3a,b. On the other hand, when compounds 3a,b were heated under reflux in ethanol with hydrazine hydrate, thiourea, or 1,1-phenylenediamine hydrochloride and a catalytic amount of piperidine 4a,b, 5a,b and 6a,b, were produced, respectively. The new compounds were tested for their antimicrobial activity. Compounds 2a–6b showed antibacterial activities, and 2a,2b and 4b showed antifungal activities.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.  相似文献   

5.
取代嘧啶化合物的合成和生物活性研究   总被引:4,自引:0,他引:4  
吴军  孙燕萍  张培志  俞庆森 《有机化学》2004,24(11):1403-1406
合成了14个新型取代嘧啶类化合物,结构经质谱、红外光谱、氢核磁共振光谱和元素分析确证.杀虫、杀菌和除草活性测定结果表明,部分化合物具有良好的杀菌活性.在嘧啶环的2-位上导入二甲氨基时表现出杀菌活性,但在嘧啶环的5-位上有甲基取代基时,杀菌活性下降.在嘧啶的4-位导入苯氧基时,显示出良好的杀菌活性,如化合物3b,3c和3e,苯环上的最优取代基是2-硝基-4-三氟甲基.  相似文献   

6.
《Analytical letters》2012,45(3):131-140
Abstract

The mass spectrometry of a series of trimethylsilylated substituted salicylanilides is reported. Information from trimethylsilyl-dg isotope labeling experiments and high resolution mass measurements were employed to ascertain the structure of fragment ions. The influence of substituent groups on the fragmentations is reported.  相似文献   

7.
设计合成了2个刚性很强的结构对称性巴比妥酸类化合物———环丙基螺环硫巴比妥酸化合物。通过红外、核磁对其结构进行了表征。其中化合物1a和1b活泼氢(N—H)的化学位移有明显区别。利用二维氢氢相关谱观察到了化合物1a结构中,环丙烷上氢质子与酰胺环上氢质子由于螺环刚性屏蔽影响使其2个环上同侧较近质子之间存在相关性,异侧较远质子之间无相关性。初步测试了2个化合物的抗小鼠电击惊厥活性:化合物1a和1b的惊厥抑制率分别为50%和70%。  相似文献   

8.
Insulin-regulated aminopeptidase (IRAP) is a new potential macromolecular target for drugs aimed for treatment of cognitive disorders. Inhibition of IRAP by angiotensin IV (Ang IV) improves the memory and learning in rats. The majority of the known IRAP inhibitors are peptidic in character and suffer from poor pharmacokinetic properties. Herein, we present a series of small non-peptide IRAP inhibitors derived from a spiro-oxindole dihydroquinazolinone screening hit (pIC50 5.8). The compounds were synthesized either by a simple microwave (MW)-promoted three-component reaction, or by a two-step one-pot procedure. For decoration of the oxindole ring system, rapid MW-assisted Suzuki-Miyaura cross-couplings (1 min) were performed. A small improvement of potency (pIC50 6.6 for the most potent compound) and an increased solubility could be achieved. As deduced from computational modelling and MD simulations it is proposed that the S-configuration of the spiro-oxindole dihydroquinazolinones accounts for the inhibition of IRAP.  相似文献   

9.
Abstract

Organophosphorus compounds containing a functional group in the a-position of the alkyl radical are of great interest in both theoretical fundamental investigations and for practical applications. Functionally substituted methyl-phosphonites and their derivatives, belonging to this broad class of organophosphorus compounds, are convenient objects for investigating mutual effects of trivalent phosphorus and a heteroatom, or functional groups attached to it in the a-position. They have also become key substances in obtaining new organophosphorus compounds. Functionally sub-stituted compounds of tetracoordinated phosphorus have been intensively investigated in recent years; rather convenient methods of synthesis of these compounds have been proposed and their properties have been studied in detail1. However, the corresponding compounds of tricoordinated phosphorus are not available or difficult to obtain. Recently we re-ported on the properties of halogen-substituted methylphos-phines and their derivatives2. The present paper is devoted to the synthesis and investigation of the reactivity of alkoxy-, dialkylamino- and carbonyl substituted methylphos-phonites and their derivatives. In synthesis of alkoxymeth-ylphosphonites and their analogs we were the first to use labile alkoxymethylmagnesium chlorides in the reactions with tricoordinated phosphorus acid chlorides3. Previously unknown dialkoxymethylphosphonites and their analogs were obtained from hypophosphorous acid and trialkylorthofor-mates. The process of esterification and dialkoxymethylat-ion of hypophosphorous acid, being dependent on a catalyst, proceeds in different ways and results in the formation of dialkoxymethylphosphonite structures  相似文献   

10.
Liquid‐crystalline (LC) properties have been induced in a number of spiropyran derivatives by the addition of methanesulfonic acid. Spiropyran derivatives containing one or two gallic acid moieties with one, two, or three long alkyl chains were prepared. Acid‐induced spiro–protonated‐merocyanine isomerization induced mesomorphism for these materials. Equimolar mixtures of methanesulfonic acid and the spiropyran derivatives with one or two dodecyloxy chains exhibited smectic A phases, whereas the spiropyran derivatives containing the gallic acid moiety with three dodecyloxy chains showed hexagonal columnar phases. On the contrary, photoirradiation of the spiropyran compounds in the bulk liquid state did not lead to the induction of mesomorphism, although the merocyanine form was induced. These results suggest that these merocyanine derivatives with ionic and nonionic moieties cannot simply form nanosegregated LC structures. Complex formation of the merocyanine form with methanesulfonic acid may play a key role in the formation of LC molecular assemblies.  相似文献   

11.
The Vilsmeier–Haack reaction of 2-amino -4-(4-substituted phenyl)-thiazoles 1, in the presence of micellar media, gives formylated derivatives 2, which upon hydrolysis afforded thiazole-5-carboxaldehydes 3. Microwave-assisted Knoevenagel condensation of 3 with active methylene compounds, in the presence of piperidine as catalyst, gives excellent yields of ylidenenitrile compounds 4. The structures of the newly synthesized compounds were established on the basis of elemental analysis, IR, 1H NMR, and 13C NMR spectral analysis. All newly synthesized compounds were screened for antibacterial activity using two Gram-positive and one Gram-negative bacterial species and their antifungal activity was screened using two fungal species.  相似文献   

12.
13.
本文报道了苯取代螺环戊烷衍生物的电子轰击(EI)正离子和化学电离正、负离子(PNCI)质谱。通过亚稳离子测定,研究了该类化合物的裂解机理。在卤代螺环戊烷的EI质谱中,分子离子峰都很弱,甚至不出现M 离子。其特征离子为[M-X]~ 、[M-2X] 和[M-X-HX]~ 。CI正离子谱有较强的[M H]~ 、[M-2X]~ 和[M-x]~ ,CI负离子谱的特征离子为[M X]~-,它们在多数情况下为基峰离子,另外还出现HX_2~-或X~-离子。  相似文献   

14.
15.
New Schiff base derivatives, 2,2′‐[naphthalene‐2,7‐diylbis(oxy)]bis[N′‐substituted acetohydrazide] ( 4a‐m ) were synthesized by the acid catalyzed condensation of aryl/hetero aromatic aldehydes with 2,2′‐ [naphthalene‐2,7‐diylbis(oxy)]diacetohydrazide ( 3 ) under reflux temperature and ultrasonic irradiation. These Schiff base derivatives were confirmed through spectral characterization using IR, 1H NMR, 13C NMR and mass spectra. All the synthesized compounds were screened for their antioxidant activity using DPPH free radical scavenging method.  相似文献   

16.
The application of non-planar scaffolds in drug design allows for the enlargement of the chemical space, and for the construction of molecules that have more effective target–ligand interactions or are less prone to the development of resistance. Among the works of the last decade, a literature search revealed spirothiazamenthane, which has served as a lead in the development of derivatives active against resistant viral strains. In this work, we studied the novel molecular scaffold, which resembles spirothiazamenthane, but combines isoxazoline as a heterocycle and cyclooctane ring as a hydrophobic part of the structure. The synthesis of new 3-nitro- and 3-aminoisoxazolines containing spiro-fused or 1,2-annelated cyclooctane fragments was achieved by employing 1,3-dipolar cycloaddition of 3-nitro-4,5-dihydroisoxazol-4-ol 2-oxide or tetranitromethane-derived alkyl nitronates with non-activated alkenes. A series of spiro-sulfonamides was obtained by the reaction of 3-aminoisoxazoline containing a spiro-fused cyclooctane residue with sulfonyl chlorides. Preliminary screening of the compounds for antiviral, antibacterial, antifungal and antiproliferative properties in vitro revealed 1-oxa-2-azaspiro[4.7]dodec-2-en-3-amine and 3a,4,5,6,7,8,9,9a-octahydrocycloocta[d]isoxazol-3-amine with activity against the influenza A/Puerto Rico/8/34 (H1N1) virus in the submicromolar range, and high values of selectivity index. Further study of the mechanism of the antiviral action of these compounds, and the synthesis of their analogues, is likely to identify new agents against resistant viral strains.  相似文献   

17.
18.
The convenient methods for the synthesis of new trimethylsilyl esters of aminomethylenediphosphonic acids are elaborated. The new substituted N‐formylaminomethylenediphosphonates are obtained via the interaction of trimethylsilyl esters of methylenediphosphonic acids with a mixture of triethyl orthoformate and ethanol. Also boron trifluoride–diethyl etherate as an effective catalyst is used for the interaction of hydrochlorides of ethoxymethylene imines with diethyl trimethylsilyl phosphite. The corresponding aminomethylenediphosphonic acids are presented.  相似文献   

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