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1.
An efficient synthetic method for the preparation of (E)- and (Z)-3(5)-(2-hydroxyphenyl)-4-styrylpyrazoles has been developed. The reaction of (E)- and (Z)-3-styrylchromones with hydrazine hydrate afforded the corresponding (E)- and (Z)-4-styrylpyrazoles, respectively, saved 4′-nitro-derivatives where both (E)- and (Z)-4′-nitro-3-styrylchromones afforded (E)-3(5)-(2-hydroxyphenyl)-4-(4-nitrostyryl)pyrazoles. The reaction mechanism for these transformations was discussed and the stereochemistry of all products was assigned by NMR experiments.  相似文献   

2.
Abstract  An efficient synthesis method for the preparation of a series of new (Z)- and (E)-3(5)-(2-hydroxyphenyl)-4-styrylpyrazoles was developed. The reaction of (Z)- and (E)-3-styrylchromones with hydrazine hydrate afforded the corresponding (Z)- and (E)-3(5)-(2-hydroxyphenyl)-4-styrylpyrazoles, except for nitro derivatives, where both (Z)- and (E)-4′-nitro-3-styrylchromones afforded (E)-3(5)-(2-hydroxyphenyl)-4-(4-nitrostyryl)pyrazoles. The reaction mechanism for these transformations is discussed and the stereochemistries of all products were established by NMR experiments. Graphical abstract     相似文献   

3.
The synthesis of 1-(4-hydroxyphenyl)-2-(2-fluoro-4-hydroxyphenyl)ethane ( FBPE ), 1-(4-hydroxyphenyl)-2-(2-chloro-4-hydroxyphenyl)ethane ( CIBPE ), 1-(4-hydroxyphenyl)-2-(2-bromo-4-hydroxyphenyl)ethane ( BrBPE ), and 1-(4-hydroxyphenyl)-2-(2-trifluoromethyl-4-hydroxyphenyl)ethane ( CF3BPE ), of the corresponding polymers based on 1,5-dibromopentane ( RBPE-5) , 1,8-dibromooctane ( RBPE-8 ), and of the copolymers based on various ratios of 1,5-dibromopentane and 1,8-dibromooctane [ RBPE-5/8(A/B )] is described. The phase transition temperatures and thermodynamic parameters of RBPE-5 and RBPE-8 polymers were compared to those of the corresponding polyethers based on 1,2-bis(4-hydroxyphenyl)ethane ( BPE ) and 1-(4-hydroxyphenyl)-2-(2-methyl-4-hydroxyphenyl)ethane ( MBPE ) which were reported previously. Both isotropic-nematic transition temperatures and corresponding thermodynamic parameters (i.e., enthalpy and entropy changes) decrease in the following order of the substituent R: H > F > CH3 > Cl > Br > CF3. This order corresponds to the increase of the breadth of the RBPE molecules, and agrees with the similar trends observed in low molar mass liquid crystals.  相似文献   

4.
l,7-Bis(4-hydroxyphenyl)-3-hydroxy-1,3-heptadien-5-oneIIwagfirstlyisolatedfromtheseedsofAIPiniablepharocalyxK.Schum.(Zingiberaceae)asanoveldiarylheptanoid.Meanwhile,l,7-his(4-hydroxyphenyl)-3-hydroxy-l,3,6-heptatTien-5-one2,aknowndiarylheptanoid,wasisolatedaswell.Therecentpublication'reportedthatIstronglyinhibitedtheaggregationofplateletinducedbycollagen,arachidonicacidandadenosinediphosphate.AdditionalresearchZprovedthat2couldactasaninhibitoroftheHIV-1integrase.Byourfindings,thesynthesi…  相似文献   

5.
利用对羟基苯甲醛和丙酮为原料,以氯化氢气体为催化剂,超声波辐射下成功合成了1,5-二-(4-羟基苯基)-1,4-戊二烯3-酮(HPD).与传统方法相比,该方法具有反应时间短,操作简便及产率高等优点,并讨论了影响产率的因素.  相似文献   

6.
Summary The Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (2 a) gave 7-hydroxy-8-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one (3 a) and 2,3-dihydro-2,6-diphenyl-3-methyl-(7H)furo[2,3-h]-1-benzopyran-7-one (7 a). 2-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (2 b) afforded4 b and7 b. 8-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4H)-1-benzopyran-4-one (12) gave only the alkali soluble product 7-hydroxy-8-methyl-6-(1-phenyl-2-propenyl)-3-phenyl-(4H)-1-benzopyran-4-one (13).3 a,4 b, and13 were further cyclized in acidic medium to9 a,10 b, and14 followed by dehydrogenation.This paper is dedicated to Dr. F. M. Dean, Department of Organic Chemistry, Robert Robinson Laboratories, University of Liverpool, Liverpool, U. K., on his retirement  相似文献   

7.
依据邻羟基二苯醚及三唑类化合物的抗菌特性及生物活性叠加原理, 将邻羟苯基和1,2,4-三唑分子片断有机结合, 设计合成了12个新型3-取代硫基-5-(1-羟基苯基)-4H-1,2,4-三唑类化合物. 首先, 水杨酸甲酯与水合肼反应生成水杨酰肼, 水杨酰肼再与硫氰酸铵和盐酸反应, 生成5-(1-羟基苯基)-4H-1,2,4-三唑-3-硫酮(3), 最后在碱性条件下化合物3与取代苯乙酮、氯苄和碘甲烷发生烷基化反应生成目标化合物, 化合物结构经 1H NMR及IR等表征确认. 抑菌测试结果表明, 当化合物质量分数为0.01%时, 目标化合物对白色念珠菌和大肠杆菌的抑菌率高达90%, 具有强抑菌活性; 对金黄色葡萄球菌的抑菌率高达80%, 具有一定的抑菌活性.  相似文献   

8.
以对称二氨基硫脲为原料,与冰醋酸反应生成5-甲基-4-氨基-1,2,4-三唑-3-硫酮(1);在弱酸性条件下,1与取代水杨醛反应生成席夫碱中间体5-甲基-4-(N-取代邻羟苯基)亚胺基-1,2,4-三唑-3-硫酮(2a~2c);最后在碱性条件下分别与N-取代苯基-2-氯乙酰胺发生烷基化反应生成15种未见报道的目标化合物3-(N-取代苯基-2-乙酰胺基)硫基-4-(N-取代邻羟苯基)亚胺基-5-甲基-1,2,4-三唑(3a~3o),其结构经IR,1H NMR,13C NMR确证.初步生物测试表明,质量分数为0.01%时,3a~3o对白色念珠菌的抑菌率均达90%以上,具有很强的抑菌活性;对金黄色葡萄球菌、大肠杆菌的抑菌率达80%以上,具有较强的抑菌活性.  相似文献   

9.
The crystal structure of the title compound(E)-ethyl 2-(4-(2,4-dimethoxy benzylide-neamino)-5-(3,4,5-trimethoxyphenyl)-4H-1,2,4-triazol-3-ylthio)acetate(4,C24H28N4O7S,Mr = 516.17) was synthesized and determined by X-ray single-crystal diffraction.The crystal belongs to the monoclinic system,space group P21/n with a = 13.162(2),b = 8.4506(13),c = 22.602(4) ,β = 99.888(3)°,μ = 0.183 mm-1,V = 2476.5(7)3,Z = 4,Dc = 1.385 g/cm3,F(000) =1088,T = 110(2) K,R = 0.0426 and wR = 0.1216 for 3859 observed reflections with I > 2σ(Ⅰ).  相似文献   

10.
报道了显色剂1-(4-硝基苯基)-3-(2-吡嗪)-三氮烯化合物的合成及其与镉(Ⅱ)的显色反应。在非离子表面活性剂Triton X-100存在下,pH 10.5的Na2B4O7-NaOH的缓冲介质中,该试剂能与镉(Ⅱ)与发生显色反应,形成摩尔比为4∶1的黄棕色配合物,配合物在波长453 nm处有最大吸收峰,表观摩尔吸光系数ε为6.90×104L.mol-1.cm-1,镉(Ⅱ)质量浓度在0~0.56μg/mL范围内遵守比尔定律。用拟定方法测不同废水中的镉(Ⅱ)。  相似文献   

11.
The compound (Z)-ethyl 5-(phenylamino)-3-(phenylimino)-3H-1,2-dithiole-4-carboxylate 3 has been synthesized by the reaction of ethylacetoacetate 1 and phenylisothiocyanate 2. Its structure has been established by 1H NMR, 13C NMR, infrared, mass spectra, and x-ray crystallography.   相似文献   

12.
A series of metal(II) complexes ML (where M?=?Cu(II), Co(II), Ni(II), Zn(II), Mn(II), Cd(II), and VO(II)) have been prepared from 3-(3-(2-hydroxyphenyl)-3-oxoprop-1-enyl)-4H-chromen-4-one and sulfanilamide. The structures of the complexes have been investigated by elemental analysis, magnetic susceptibility, molar conductance, IR, UV-Vis, NMR, mass, and ESR spectral studies. Conductivity measurements reveal that the complexes are non-electrolytes, except the oxovanadium complex. Spectral and other data show square pyramidal geometry for oxovanadium and octahedral for the other complexes. The redox behaviors of the copper and vanadyl complexes have been studied through cyclic voltammetry. Antimicrobial activities of the compounds against several microorganisms indicate that some complexes have higher activity than free ligand. The compounds may serve as photoactive materials as indicated from their characteristic fluorescence properties. The second harmonic generation efficiency of the ligand was found to be higher than that of urea and KDP.  相似文献   

13.
The synthesis of (S)-2-(3-arylacrylamido)-3-{4-[2-(5-methyl-2-phenyloxazol-4-yl)etho- xy]phenyl}propanoic acids is described. Their structures were confirmed by ^1H-NMR.  相似文献   

14.
3-(3-Aryl-4-formyl-1-pyrazolyl)propionic acids are converted by Knoevenagel condensation under conditions of microwave activation into 3-[3-aryl-1-(2-ethoxycarbonyl)-4-pyrazolyl]acrylic acids. Reduction of the latter with hydrazine hydrate in the presence of Raney nickel gives 3-[3-aryl-1-(2-ethoxycarbonyl)-4-pyrazolyl]propionic acids. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 686–690, May, 2006.  相似文献   

15.
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   

16.
Beckmann rearrangement of N-[3-(1-hydroxyimino)ethyl-2,2-dimethylcyclobutyl]acetylanthranilic acid, and its 5-bromo and 4-chloro derivatives gives the corresponding N-(3-acetylamino-2,2-dimethylcyclobutyl)acetylanthranilic acids. Treatment of these acylanthranilic acids with formamide gives 2-(3-acetylamino-2,2-dimethylcyclobutyl)methyl-4(3H)-quinazoline and its 6-bromo and 7-chloro derivatives.  相似文献   

17.
A new quinazolinone compound 2,3-dihydro-2-(2-hydroxyphenyl)-3-phenylquinazolin-4(IH)-one 3 ([C2oH16O2N2]-C2H5OH, Mr = 362.42) and compound 2-(2-hydroxybenzylidene-amino)-N-phenyl-benzamide 2 (C2oH16O2N2, Mr = 316.34) were prepared from a precursor of 2-amino-N-phenyl-benzamide 1 (C13H12ON2, Mr = 212.25). Compound 3 was characterized by single-crystal X-ray diffraction analysis. The crystal belongs to orthorhombic,space group Pbca with a = 1.2889(11), b = 1.6170(14), c = 1.7729(15) nm, V= 3.695(6) nm^3, Z= 8, F(000) = 1536, Mr = 362.42, Dc = 1.303 g/cm^3, μ(MoKa) = 0.087 mm^-1, R = 0.0447 and wR= 0.0879. The crystal structure analysis indicates that the title compound has a two-dimensional network structure formed by hydrogen bonds and electrostatic interactions.  相似文献   

18.
The title compound 2-(2-chloro-4-nitrophenyl)-4-(4-chlorophenyl)-3a,4- diethoxy- 2,3,3a, 4-tetrahydrochromeno[3,4-d][1,2,3]diazaphosphole 2 (C29H30Cl2N3O7P, Mr = 633.44) was synthesized and its structure was characterized by IR, MS, ^1H NMR, ^13C NMR, ^31p NMR, elemental analysis and single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1^-, a = 9.1549(3), b = 10.7168(4), c = 17.6272(6)A, α = 102.9363(12), β = 90.2713(9), γ = 117.4265(10)°, V= 1484.41(9)A^3, Z= 2,μ(MoKa) = 0.323, F(000) = 658, Z= 2, De= 1.417 g/cm^3, the final R = 0.0687 and wR = 0.2066 for 4943 observed reflections (I 〉 2σ(I)). X-ray analysis reveals that the diazaphospholine ring is almost planar and the two ethoxy groups bonded on the 3a- and 4-positions are in trans configurations. Its antiproliferative activity was also tested in vitro against four human tumor cell lines.  相似文献   

19.
A new anti-inflammatory active phenylpropenoid, (R,E)-1-[4-(3-hydroxyprop-1-enyl) phenoxyl]-3-methylbutane-2,3-diol (1), isolated from the stem wood of Zanthoxylum integrifoliolum, has been synthesized for the first time using commercially available 4-hydroxy benzaldehyde (2). The key step involves the Sharpless asymmetric dihydroxylation of olefin (3).

Additional information

ACKNOWLEDGMENTS

The authors (V. S., K. R., and J. J. P. S.) are thankful to the University Grants Commission and the Council of Scientific and Industrial Research, New Delhi, India, for financial support and to Dr. J. S. Yadav, director, Indian Institute of Chemical Technology, for his encouragement.  相似文献   

20.
以槲皮素为起始原料,经酰化、醚化、苄醚化、脱苄、甲基化、水解6步反应合成了18F标记前体3'-甲氧基-7-对甲苯磺酰氧丙氧基槲皮素,其结构经1H NMR,13C NMR和HR-MS(ESI)确证。  相似文献   

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