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1.
报道了取代的邻羟基苯乙酮(1a~1e)经Vilsmeier-Haack反应一步制得3-醛基色酮(2a~2e),2a~2e与取代的芳酰肼(3a~3c)缩合制得15个酰腙类化合物(4a~4o),4a~4o在醋酸酐作用下关环得15个3-(2-苝二唑啉基)-色酮(5a~5o),并通过元素分析,IR,~1H NMR和MS诺数据确证了上述化合物的结构。  相似文献   

2.
研究了3-(2'-苯基-1', 2', 3'-连三唑-4'-基)-4-氨基-5-巯基-1, 2, 4-三唑(1)与取代苯甲酸和脂肪酸(2a-r)在POCl3催化下的反应, 共合成得到18个新的3-(2'-苯基-1', 2', 3'-连三唑-4'-基)-6-烷基/芳基-均三唑并[3, 4-b]-1, 3, 4-噻二唑(3a-r), 经元素分析,IR, 1H NMR和MS进行了结构确证。  相似文献   

3.
Conjugate addition of lithium dibenzylamide to tert-butyl (+/-)-3-methylcyclopentene-1-carboxylate occurs with high levels of stereocontrol, with preferential addition of lithium dibenzylamide to the face of the cyclic alpha,beta-unsaturated acceptor anti- to the 3-methyl substituent. High levels of enantiorecognition are observed between tert-butyl (+/-)-3-methylcyclopentene-1-carboxylate and an excess of lithium (+/-)-N-benzyl-N-alpha-methylbenzylamide (10 eq.) (E > 140) in their mutual kinetic resolution, while the kinetic resolution of tert-butyl (+/-)-3-methylcyclopentene-1-carboxylate with lithium (S)-N-benzyl-N-alpha-methylbenzylamide proceeds to give, at 51% conversion, tert-butyl (1R,2S,3R,alphaS)-3-methyl-2-N-benzyl-N-alpha-methylbenzylaminocyclopentane-1-carboxylate consistent with E > 130, and in 39% yield and 99 +/- 0.5% de after purification. Subsequent deprotection by hydrogenolysis and ester hydrolysis gives (1R,2S,3R)-3-methylcispentacin in > 98% de and 98 +/- 1% ee. Selective epimerisation of tert-butyl (1R,2S,3R,alphaS)-3-methyl-2-N-benzyl-N-alpha-methylbenzylaminocyclopentane-1-carboxylate by treatment with KO'Bu in 'BuOH gives tert-butyl (1S,2S,3R,alphaS)-3-methyl-2-N-benzyl-N-alpha-methylbenzylaminocyclopentane-1-carboxylate in quantitative yield and in > 98% de, with subsequent deprotection by hydrogenolysis and ester hydrolysis giving (1S,2S,3R)-3-methyltranspentacin hydrochloride in > 98% de and 97 +/- 1% ee.  相似文献   

4.
Preparative method for the synthesis of lithium, sodium, cesium, and calcium salts of (E)-4-(5-arylisoxazol-3-yl)methyleneaminobutanoic, (E)-6-(5-arylisoxazol-3-yl)methyleneaminohexanoic, (E,S)-3-methyl-2-(5-arylisoxazol-3-yl)methyleneaminobutanoic, (E,S)-4-methyl-2-(5-arylisoxazol-3-yl)methyleneaminopentanoic and (E,2S,3S)-3-methyl-2-(5-arylisoxazol-3-yl)methyleneaminopentanoic acids was developed by reacting 5-phenyl(4-tolyl)isoxazole-3-carbaldehydes with amino acids like 4-aminobutyric and 6-aminocaproic acids, L-valine, L-leucine or L-isoleucine in the presence of lithium hydride, sodium methoxide, cesium carbonate or calcium hydride in boiling methanol.  相似文献   

5.
本文制备了一系列新的3-烷基/芳基-6-(3'-吡啶基)均三唑并[3,4-b]-1,3,4-噻二唑类稠杂环化合物,确认了结构,筛选了其中代表物的生物活性。  相似文献   

6.
The possibility of the direct preparation of 2-(3'-coumarinyl)-1,3-indandione and its derivatives by condensing phthalic and substituted phthalic anhydrides with 3-coumarinylacetic acid in acetic anhydride solution in the presence of triethylamine has been shown. The bromination and hydroxymethylation of 2-(3'coumarinyl)-1,3-indandione and its substituted derivatives have been performed.  相似文献   

7.
研究了2-苯基-1, 2, 3-三唑-4-羧酸(1)与3-烷基/芳基-4-氨基-5-巯基-1, 2, 4-三唑(2a~o)在POCl~3催化下, 脱水缩合得到15个新的3-烷基/芳基-6-(2'-苯基-1', 2', 3'-三唑-4'-基)均三唑并[3,4-b]-1, 3, 4-噻二唑类化合物(3a~o)。  相似文献   

8.
A complete series of compounds with the anions [(TeCF3)(3-x)I(x)]- (x = 0-2) had been prepared and characterised in the solid state and by NMR spectroscopic methods. Dynamic behaviour in solution can be assumed for [(TeCF3)3]- and [(TeCF3)2I]-, while in the solid state all three bis(triphenylphosphoranyliden)ammonium (PNP) salts resemble structures found in triiodides. The molecular structures of [PNP][(TeCF3)(3-x)I(x)]- (x = 0-2) are discussed in comparison with [PNP]I3, I2, and Te2(CF3)2. On this basis, the structures of the [(TeCF3)3]- and [(TeCF3)I2]- ions are comparable to symmetric I3- ions, while the [(TeCF3)2I]- ion resembles an asymmetric I3- unit.  相似文献   

9.
3-(Pivaloylamino)- and 3-(acetylamino)-4(3H)-quinazolinones react with alkyllithium reagents to give 1,2-addition products in very good yields. Lithiation takes place with LDA and is regioselective at position 2. The lithium reagents thus obtained react with a variety of electrophiles to give the corresponding substituted derivatives in very good yields. Reactions of the lithium reagents with iodine give oxidatively dimerized cyclic structures. 3-(Pivaloylamino)- and 3-(acetylamino)-2-ethyl-4(3H)-quinazolinones and 3-(pivaloylamino)- and 3-(acetylamino)-2-propyl-4(3H)-quinazolinones are lithiated at the benzylic position with LDA. The lithium reagents so produced also react with a variety of electrophiles to give the corresponding 2-substituted-4(3H)-quinazolinone derivatives in very good yields. However, lithiation of 3-(acylamino)-2-(1-methylethyl)-4(3H)-quinazolinones was unsuccessful, as were lithiations of compounds having a diacetylamino group at position 3. The amide groups have been cleaved in good yield under basic or acidic conditions from some of the products to provide access to the free amino compounds.  相似文献   

10.
Novel C-nucleosides of tiazofurin analogue (2-[2-(hydroxymethyl)-1,3-dioxolan-5-yl] 1,3-thiazole-4-carboxamide) and its thiol-substituted derivative (2-[2-(mercaptomethyl)-1,3-dioxolan-5-yl] 1, 3-thiazole-4-carboxamide) were synthesized from methyl acrylate through a multistep procedure. Their structures were confirmed by IR, ^1HNMR, ^13CNMR and elemental analysis.  相似文献   

11.
正如前文报道,l,3,4—噻二唑类杂环之所以有除草,植物生长调节,驱虫以及消炎等多种生物活性,无疑起因于噻唑母核。尽管母核上取代基不起主导作用,但它作为辅助基,在改善分子溶解性以及药效方面所产生的影响是不能忽略的。因而深入研究各种生物活性基团导入噻二唑环母核以制得多结构单元聚集于同一分子中的噻二唑新衍生物,对于开发多功能新药具有一定的理论意义和实际价值。  相似文献   

12.
1,4-苯并二氧六环木脂素类天然产物多数具有增加胆碱乙酰化酶和抗肝毒等活性 ,其活性主要源于 1 ,4-苯并二氧六环官能团 [1] . 1 ,4-苯并二氧六环木脂素的消旋全合成已有报道 [2 ] ,但其不对称合成还是空白[3] .我们发展了一条对映选择性合成 1 ,4-苯并二氧六环木脂素的简捷有效的路线 .基于前面的工作 [4 ] ,我们发现 1 ,4-苯并二氧六环醛类衍生物是合成此类天然产物的关键中间体 ,选择 2 - (4-羟基- 3-甲氧基 ) - 3-羟甲基 - 1 ,4-苯并二氧六环 - 6-醛 (1 )作为目标分子 ,其合成路线如下 :Reagents and conditions:( ) Me OH,H2 SO4,9…  相似文献   

13.
The new series of 3-(2-chlorophenyl)- and 3-(3-chlorophenyl)-pyrrolidine-2,5-dione-acetamide derivatives as potential anticonvulsant and analgesic agents was synthesized. The compounds obtained were evaluated in the following acute models of epilepsy: maximal electroshock (MES), psychomotor (6 Hz, 32 mA), and subcutaneous pentylenetetrazole (scPTZ) seizure tests. The most active substance-3-(2-chlorophenyl)-1-{2-[4-(4-fluorophenyl)piperazin-1-yl]-2-oxoethyl}-pyrrolidine-2,5-dione (6) showed more beneficial ED50 and protective index values than the reference drug—valproic acid (68.30 mg/kg vs. 252.74 mg/kg in the MES test and 28.20 mg/kg vs. 130.64 mg/kg in the 6 Hz (32 mA) test, respectively). Since anticonvulsant drugs are often effective in neuropathic pain management, the antinociceptive activity for two the promising compounds—namely, 6 and 19—was also investigated in the formalin model of tonic pain. Additionally, for the aforementioned compounds, the affinity for the voltage-gated sodium and calcium channels, as well as GABAA and TRPV1 receptors, was determined. As a result, the most probable molecular mechanism of action for the most active compound 6 relies on interaction with neuronal voltage-sensitive sodium (site 2) and L-type calcium channels. Compounds 6 and 19 were also tested for their neurotoxic and hepatotoxic properties and showed no significant cytotoxic effect.  相似文献   

14.
The synthesis of a ligand containing as an electroactive core a tetrathiafulvalene moiety, 3-[3-(diphenylphosphino)propylthio]-3',4,4'-trimethyl-tetrathiafulvalene, is reported. Its versatile ability to act as a bidentate or a monodentate ligand, as demonstrated by the metal carbonyl complexes obtained, is described. The novel cis-Mo(CO)(4)(P-TTF)(2) 4 and cis-W(CO)(4)(P,S-TTF) 6 complexes have been characterized by X-ray diffraction analyses and cyclic voltammetry measurements. Within complex 4, no significant influence of the two electroactive ligands on the molybdenum center was detected, whereas, in complex 6, a weak influence of the TTF redox-active core can be observed on the redox behavior of the metal center.  相似文献   

15.
1 INTRODUCTIONInrecentyears ,triazolo[3,4, b] 1 ,3,4 thiadiazolederivativeshavebeenat tractingmuchattentionfromchemistsandpharmacologistsbecausetheyshowbroadspectraofbiologicalactivities,suchasinsecticidal[1 ] ,antifungal[2 ] ,herbicidal[3] ,an tibacterial[4] ,hypotensiv…  相似文献   

16.
Natural diarylheptanoids have significant bioactivities. Some of them are potent inhibitors against prostaglandin biosynthesizing enzyme (PG synthetase) and 5-lipoxygenase (LT synthetase)1-2. Compound 1 was firstly isolated from Alnus rubra bark3. So far its synthesis has not been reported yet. Herein, we report the synthesis of compound 1. Meantime, compound 24 was also obtianed as an intermediate. Compound 7 and 16 were converted to compound 10 and 18 respectively, because compound 1…  相似文献   

17.
Seven platinum(II) complexes isolated from thiosemicarbazones derived from 2-, 3- and 4-formylpyridine and 2-, 3-, and 4-acetylpyridine have been characterised by microanalyses, molar conductivities and by their i.r. and 1H-n.m.r. spectra.  相似文献   

18.
3-(2-, 3- and 4-Pyridyl)-2-methoxythiophenes have been prepared in good yields through the Pd(0)-cat-alyzed coupling of the three isomeric bromopyridines with 3-trimethylstannyl-2-methoxythiophene. This compound was prepared through halogen-metal exchange of 3-bromo-2-methoxythiophene followed by stannylation. 3-Bromo-2-methoxythiophene was prepared by dibromination and α-debromination of 2-methoxythiophen. Most attempts to demethylate 2-methoxy-3-pyridylthiophenes using a large variety of reagents failed, probably due to the instability and high reactivity of the desired 3-pyridyl-2-hydroxythiophene systems. Only 2-methoxy-3-(3-pyridyl)thiophene reacted with boron tribromide to give 3-(3-pyridyl)-3-thiolene-2-one, which only was stable in ether solution at ?20°. The attempted demethylation of 2-methoxy-3-(2-pyridyl)thiophene with trimethylsilane chloride/sodium iodide in refluxing acetonitrile led to a dimer. Demethylation of the 2-methoxy-3-pyridylthiophenes with dibenzyl diselenide and sodium borohydride gave 3-pyridylthiophan-2-ones. A number of other routes to prepare 3-pyridyl-2-hydroxythiophenes were also explored, but none of them gave the desired compounds. On the other hand, the 4-(2-, 3-, and 4-pyridyl)-2-hydroxythiophene systems could easily be prepared by hydrogen peroxide oxidation of the corresponding 4-pyridyl-2-thiopheneboronic esters, which were obtained from 2-bromo-4-pyridylthiophenes by halogen-metal exchange followed by reaction with ethyl borate. The 2-bromo-4-pyridylthiophenes were prepared by dibromination of the known 3-pyridylthiophenes to the 2,5-dibromo derivatives, and removal of the 2-bromine by halogen-metal exchange at ?100°, followed by hydrolysis. The 1H nmr and ir spectroscopic investigations show that these quite stable 2-hydroxythiophene systems exist exclusively in the 4-pyridyl-3-thiolen-2-one forms.  相似文献   

19.
2-(2-, 3- and 4-pyridyl)-3-hydroxythiophenes and 4-(2-, 3- and 4-pyridyl)- 3-hydroxythiophenes have been prepared by hydrogen peroxide oxidation of the corresponding boronic esters. In the former case the boronic esters were obtained in three steps from 2,3-dibromothiophene via the corresponding 3-bromo-2-pyridylthiophenes synthesized by Pd(0)-catalyzed coupling between 3-bromo-2-trimethylstannylthiophene and the corresponding bromopyridines. In the latter case the known isomeric pyridylthiophenes were converted into the corresponding boronic esters in three steps via tribromo- and 3-bromo-4-pyridylthiophenes successively. 4-(3- and 4-pyridyl) thiophen-2(5H)-ones were also obtained in the syntheses of 4-(3- and 4-pyridyl)-3-hydroxythiophene. They are suggested to arise from rearrangement during the halogen-metal exchange. Spectroscopic investigations by 1H NMR and IR show that these hydroxythiophene systems exist exclusively as enol forms.  相似文献   

20.
3-(2-卓二唑啉基) - 色酮类化合物的合成研究   总被引:5,自引:2,他引:3  
报道了取代的邻羟基苯乙酮(1a~1e)经Vilsmeier-Haack反应一步制得3-醛基色酮(2a~2e),2a~2e与取代的芳酰肼(3a~3c)缩合制得15个酰腙类化合物(4a~4o),4a~4o在醋酸酐作用下关环得15个3-(2-卓二唑啉基)-色酮(5a~5o),并通过元素分析,IR,^1^HNMR和MS谱数据确证了上述化合物的结构。  相似文献   

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