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1.
1 INTRODUCTION 2-Aminochromene is an important class of com- pounds found as the main compounds of many naturally occurring products employed as cos- metics and pigments[1] and utilized as potential biodegradable agrochemicals[2~4]. The utility of fluoride salts as potential base in variety of syn- thetic reactions has been recognized in recent years[5, 6]. However, low solubility of fluoride salts in ordinary solvents limits their wide applications in organic syntheses. On the other ha…  相似文献   

2.
1 INTRODUCTION The nature and topography of the herbicide binding site in the reaction center of photosystem Ⅱ (PSⅡ) have been the subject of intense interest for many years. Among several commercially important herbicides with different structures such as atrazine and polypeptide of the PSII reaction center[1], the cyanoacrylates with general structure 1 have proved hightly potent and useful as probes[2, 3] of the receptor because their activities as inhibitors of photosynthetic ele…  相似文献   

3.
1 INTRODUCTION Triazole nuclei appear frequently in the structures of various natural products and biologically active compounds, notably thiamine (vitamin B), peni- cillins, antibiotics such as micrococcin[1], and many metabolic products of fungi and p…  相似文献   

4.
柴卉  刘广飞  刘浪  贾殿赠 《结构化学》2005,24(9):1091-1095
1 INTRODUCTION 4-Acyl pyrazolones and their derivatives, reported to behave as effective chelating and extracting rea- gents for many metal ions, not only play a key role in coordination compounds with wide applications in several fields, from new materials[1] to catalysts[2] as precursors for CVD in the microe-lectronic Indus- try[3] and as potential antitumourals[4], but also are the focus of research as potential antifungal agro- chemicals and widely used as antiviral, antipyretic anal…  相似文献   

5.
1 INTRODUCTION Inorganic solid supports as catalysts resulting in higher selectivity, milder conditions and easier work-up has been reported as useful catalysts for many reactions [1~3]. Recently, we have reported the Knoevenagel condensation and some other reactions[4~6] catalyzed by KF-Al2O3. In this paper, we discussed the crystal structure of the title compound synthesized by the reaction of 2-cyano-3-(3,4-methylenedioxylphenyl)acrylonitrile and 5,5-dimethyl-1,3-cyclohexanedione in…  相似文献   

6.
 The hydroformylation of 1-hexene catalyzed by rhodium-TPPTS complexes in the ionic liquid [bmim]BF4 was studied. The activity and selectivity of the rhodium-TPPTS complexes in [bmim]BF4 were much higher than those reported in other ionic liquids. The TOF of 1-hexene and selectivity for aldehyde were 1508 h-1 and 92%, respectively, under the optimum conditions. The high activity of the catalyst is ascribed to the absence of halide ions as well as the much higher solubility of hydrogen and rhodium-TPPTS complexes in [bmim]BF4 than in [bmim]PF6.  相似文献   

7.
程琳  应磊  杨小玲  蹇锡高 《中国化学》2005,23(2):200-203
A new monomer diacid, 1,2-dihydro-2-(4-carboxylphenyl)-4-[4-(4-carboxylphenoxy)-3-methylphenyl]phtha-lazin-1-one (3), was synthesized through the aromatic nucleophilic substitution reaction of a readily available unsymmetrical phthalazinone 1 bisphenol-like with p-chlorobenzonitrile in the presence of potassium carbonate in N,N-dimethylacetamide and alkaline hydrolysis. The diacid could be directly polymerized with various aromatic diamines 4a-4e using triphenyl phosphite and pyridine as condensing agents to give five new aromatic poly(ether amide)s 5a-5e containing the kink non-coplanar heterocyclic units with inherent viscosities of 1.30-1.54 dL/g.The polymers were readily soluble in a variety of solvents such as N,N-dimethylformamide (DMF), N,N-dimethyl-acetamide (DMA), dimethylsulfoxide (DMSO), N-methyl-2-pyrrolidinone (NMP), and even in m-cresol and pyridine (Py). The transparent, flexible and tough films could be formed by solution casting. The glass transition tem-peratures Tg were in the range of 286-317℃.  相似文献   

8.
1 INTRODUCTION Acridine derivatives are described to have many applications, such as biological fluorescent probes[1] as well as anti-tumor[2], anti-bacterial[3], anti-HIV[4] and anti-malarial[5] agents. Because of the importance of acridine derivatives, much work has been done for several decades. Among them the classical synthetic methods involve condensing functionalized anilines and o-halogeno- benzoic acid derivatives as well as several other steps resulting in the desired acridine[…  相似文献   

9.
李明  郭维斯  文丽荣  曲波 《结构化学》2006,25(1):108-112
1INTRODUCTION Pyrazolo[1,5-a]pyrimidine derivatives have shown various biological activities in the terms of antibac-terial,antischistosomal and xanthine oxidase inhibi-tors[1~5].The enaminones are highly reactive inter-mediates and have been extensively used as build-ing blocks in organic synthesis especially in the he-terocyclic compounds[6~8].In addition,a great deal of interest has been focused on the synthesis of py-razolo[1,5-a]pyrimidine through versatile enamino-nes because of thei…  相似文献   

10.
1 INTRODUCTION We are presently involved in the synthesis and photodimerization of the analogues of trans-2-sty- rylbenzoxazole (BOEP), which have been widely reported as fluorescent whiteners and remedies[1]. Some structures of BOEP derivatives and thei…  相似文献   

11.
Introduction3,6- Disubstituted- 7H- 1 ,2 ,4- triazolo[3,4- b][1 ,3,4]thiadiazines are amongst the various hete-rocycles that received considerable attention duringthe last two decades as potential biologically activeagents.This kind of N- bridged heterocycles hasbeen reported to possess the wide spectrum of bio-logical properties,such as antimicrobial[1] ,an-tibacterial,antifungal[2 ] ,antiinflammatory[3 ] ,di-uretic[4] ,anthelmintic,and analgesic properties[5] .They can be also used as plant…  相似文献   

12.
1INTRODUCTION It has been reported that3,6-disubstituted-7H-1,2,4-triazolo[3,4-b][1,3,4]thiadiazines have a broad spec-trum of bioactivities,such as antimicrobial[1],antibac-terial,antifungal[2],anti-inflammatory[3],diuretic[4],an-thelmintic and analgesic[5].They can also be used as plant-growth regulating agents[6],photographic coup-lers,dyes for improved preservability and absorption characteristics,and inhibitors of malignant cellularZOU K.H.et al.:Syntheses and Crystal Structures o…  相似文献   

13.
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   

14.
《结构化学》2004,23(4):358-360
1INTRODUCTION4H-Chromeneisaconstructionunitofsomenaturalproducts.4H-Chromeneswithaminoandcyanogroupsarealsosynthonofsomespecialnaturalproducts[1,2].Thesubstituted4H-chromenespossessawiderangeofpharmacologicalactivi-ties[3~5].Inordertoinvestigatetheactivi…  相似文献   

15.
胡扬根  徐靖  丁明武 《结构化学》2009,28(6):689-692
The crystal structure of the title compound ethyl 3-(4-chlorophenyl)-3,4-dihydro-6- methyl-4-oxo-2-(pyrrolidin-1-yl)furo[2,3-d]pyrimidine-5-carboxylate (C20H20ClN3O4, Mr= 401.84) has been prepared and determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group P21/n with a = 20.6215(9), b = 8.5311(4), c = 21.6886(9) A^°, β = 91.607(1)°, V = 3814.0(3)A^°^3, Z = 8, Dc = 1.400 g/cm^3, F(000) = 1680, μ = 0.233 mm^-1, R = 0.0718 and wR = 0.1545 for 6717 observed reflections with I 〉 2σ(I). X-ray diffraction analysis reveals two crystallographically independent molecules in the asymmetric unit.  相似文献   

16.
The title compound (C22H18N2O3) has been synthesized by the reaction of 3,4-dimethoxybenzaldehyde,malononitrile and 1-naphthol in ethanol in the presence of piperidine,and its structure was characterized by elemental analysis,IR,1H NMR and X-ray single-crystal diffraction.The crystal belongs to monoclinic,space group C2/c with a=24.221(6),b=9.016(2),c=17.003(5)A,β=93.16(1)°,V=3707(2)A3,Mr=358.38,Z=8,Dc=1.284g/cm3,μ(MoKα)=0.087mm-1,F(000)=1504,the final R=0.0432 and wR=0.1085.X-ray analysis reveals that the atoms of C(1),C(2),C(3),C(4),C(5) and O(1) form a boat-form six-membered ring in which the C(1)-C(2)(1.349(3)A) is a C=C double bond.  相似文献   

17.
The reaction of cyanogen chloride with [1-(4-C(7)H(7))-12-(C(5)H(3)-3,4-(CH(3))(2))-C(2)B(10)H(10)] (7) was found to yield two new C(5)-substituted carborane cluster-based compounds, [1-(4-C(7)H(7))-12-(C(5)H(2)-3-(CN)-3,4-(CH(3))(2))-C(2)B(10)H(10)] (8) and [1-(4-C(7)H(7))-12-(C(5)H-2,4-(CN)(2)-3,4-(CH(3))(2))-C(2)B(10)H(10)] (9). This cyano-substitution pattern is in contrast to the known substitution for the analogous organic quinarene[5.6.7] system. The observed unique cluster-based products may be understood by a combination of steric and electronic effects. Compounds 8 and 9 were characterized by complete multinuclear NMR, (1)H-(1)H COSY NMR, (1)H-(13)C HMQC NMR, FTIR, UV-Vis, IR, MS data and a single crystal analysis for 8 [X-ray data for 8: C(17)H(25)B(10)N, monoclinic, space group P2(1)/n with cell constants a = 8.6794(17) ?, b = 11.021(2) ?, c = 43.175(9) ?, β = 91.00(3)°, V = 4129.2(14) ?(3), Z = 8, R(1) = 0.0729, wR(2) = 0.1464].  相似文献   

18.
1 INTRODUCTION Biginelli reaction is a three-component condensa-tion of ethyl acetoacetate, benzaldehyde and urea forthe synthesis of 3,4-dihydropyrimidin-2(1H)-ones(Scheme 1). The reaction can be carried out in aone-pot fashion in alcohol solution in t…  相似文献   

19.
A new manganese coordination polymer 1, [Mn(H2O)4(L)]n(ClO4)2n·2nH2O·3nL (L = 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene), has been synthesized and structurally characterized. The crystal structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group Pn with a = 13.9176(8), b = 15.4754(9), c = 15.9670(9) , β = 99.5010(10)o, V = 3391.8(3) 3, Z = 2, C56H68Cl2MnN16O14 , Mr = 1315.10, Dc = 1.288 g/cm3, μ = 0.344 mm-1, F(000) = 1374, R = 0.0733 and wR = 0.2035. In the crystal the manganese atom is six-coordinated by two nitrogen atoms from 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene and four oxygen atoms from water molecules, completing an octahedral geometry. The title complex exhibits a novel supramolecular layer architecture sustained by the concurrence of coordination bonds, hydrogen bonds, and π-π stacking interactions.  相似文献   

20.
1 INTRODUCTION Since Biginelli firstly reported the synthesis of 3,4-dihydropyrimidin-2(1H)-ones in 1893, this com- pound has been found to emerge as calcium channel blockers, antihypersive agents and a-antagonists[1]. Consequently, this Biginelli reacti…  相似文献   

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