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1.
The toxicity studies of free 5‐[(E)‐2‐(aryl)‐1‐diazenyl]‐2‐hydroxybenzoic acid and 2‐[(E)‐2‐(3‐formyl‐4‐hydroxyphenyl)‐1‐diazenyl]benzoic acid and their tri‐n‐butyltin(IV) complexes were evaluated by using sea urchin early developmental stages as recommended model organisms for toxicity tests. The novel complexes, as the parent tri‐n‐butyltin(IV) chloride (TBTCl), caused mitosis block and induced high embryonic mortality in sea urchin. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

2.
An efficient one‐pot synthesis of 3‐[(4,5‐dihydro‐1H‐pyrrol‐3‐yl)carbonyl]‐2H‐chromen‐2‐one (=3‐[(4,5‐dihydro‐1H‐pyrrol‐3yl)carbonyl]‐2H‐1‐benzopyran‐2‐one) derivatives 4 by a four‐component reaction of a salicylaldehyde 1 , 4‐hydroxy‐6‐methyl‐2H‐pyran‐2‐one, a benzylamine 2 , and a diaroylacetylene (=1,4‐diarylbut‐2‐yne‐1,4‐dione) 3 in EtOH is reported. This new protocol has the advantages of high yields (Table), and convenient operation. The structures of these coumarin (=2H‐1‐benzopyran‐2‐one) derivatives, which are important compounds in organic chemistry, were confirmed spectroscopically (IR, 1H‐ and 13C‐NMR, and EI‐MS) and by elemental analyses. A plausible mechanism for this reaction is proposed (Scheme 2).  相似文献   

3.
The crystal structures of 2‐hydroxy‐5‐[(E)‐(4‐nitrophenyl)diazenyl]benzoic acid, C13H9N3O5, (I), ammonium 2‐hydroxy‐5‐[(E)‐phenyldiazenyl]benzoate, NH4+·C13H9N2O3, (II), and sodium 2‐hydroxy‐5‐[(E)‐(4‐nitrophenyl)diazenyl]benzoate trihydrate, Na+·C13H8N3O5·3H2O, (III), have been determined using single‐crystal X‐ray diffraction. In (I) and (III), the phenyldiazenyl and carboxylic acid/carboxylate groups are in an anti orientation with respect to each other, which is in accord with the results of density functional theory (DFT) calculations, whereas in (II), the anion adopts a syn conformation. In (I), molecules form slanted stacks along the [100] direction. In (II), anions form bilayers parallel to (010), the inner part of the bilayers being formed by the benzene rings, with the –OH and –COO substituents on the bilayer surface. The NH4+ cations in (II) are located between the bilayers and are engaged in numerous N—H...O hydrogen bonds. In (III), anions form layers parallel to (001). Both Na+ cations have a distorted octahedral environment, with four octahedra edge‐shared by bridging water O atoms, forming [Na4(H2O)12]4+ units.  相似文献   

4.
Treatment of {[(benzyloxy)carbonyl]amino}‐substituted sulfones 1 with 2‐[(trimethylsilyl)oxy]furan ( 2 ) in the presence of InCl3 as a catalyst at room temperature produced the γ‐butenolactone derivatives 3 and 4 containing a protected amino group (Scheme 1). The products were formed in high yields (81–92%) within 3–10 h favoring the anti‐isomer 3 .  相似文献   

5.
The monomer 5‐[(5‐ethynyl‐1‐naphthyl)ethynyl]‐N,N‐dimethylnaphthalen‐1‐amine was satisfactory obtained through the heterocoupling reaction of 5‐ethynyl‐N,N‐dimethylnaphthalen‐1‐amine and 4‐(5‐iodo‐1‐naphthyl)‐2‐methyl‐3‐butyn‐2‐ol catalyzed by a palladium–copper system, followed by acetone elimination. Poly{5‐[(5‐ethynyl‐1‐naphthyl)ethynyl]‐N,N‐dimethylnaphthalen‐1‐amine} was obtained through the reaction of the acetylene monomer with homogeneous rhodium and palladium catalyst complexes. The structure of the polymers always showed a trans–cisoidal chain configuration on the basis of IR and NMR spectra. Moreover, only for the rhodium catalyst complex in methanol was a dimeric product isolated in a very low yield, having a conjugated terminal ene–yne structure, which permitted the consideration of a metallated chain‐transfer intermediate in the polymer propagation. The mass determination of the polymers, by osmometry and gel permeation chromatography techniques, showed low average molecular weights. The kinetics of the catalyzed polymerization were analyzed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2038–2047, 2007  相似文献   

6.
The diorganotin(IV) complexes of 5‐[(E)‐2‐aryldiazen‐1‐yl]‐2‐hydroxybenzoic acid are of interest because of their structural diversity in the crystalline state and their interesting biological activity. The structures of dimethylbis{2‐hydroxy‐5‐[(E)‐2‐(4‐methylphenyl)diazen‐1‐yl]benzoato}tin(IV), [Sn(CH3)2(C14H11N2O3)2], and di‐n‐butylbis{2‐hydroxy‐5‐[(E)‐2‐(4‐methylphenyl)diazen‐1‐yl]benzoato}tin(IV) benzene hemisolvate, [Sn(C4H9)2(C14H11N2O3)2]·0.5C6H6, exhibit the usual skew‐trapezoidal bipyramidal coordination geometry observed for related complexes of this class. Each structure has two independent molecules of the SnIV complex in the asymmetric unit. In the dimethyltin structure, intermolecular O—H…O hydrogen bonds and a very weak Sn…O interaction link the independent molecules into dimers. The planar carboxylate ligands lend themselves to π–π stacking interactions and the diversity of supramolecular structural motifs formed by these interactions has been examined in detail for these two structures and four closely related analogues. While there are some recurring basic motifs amongst the observed stacking arrangements, such as dimers and step‐like chains, variations through longitudinal slipping and inversion of the direction of the overlay add complexity. The π–π stacking motifs in the two title complexes are combinations of some of those observed in the other structures and are the most complex of the structures examined.  相似文献   

7.
In the present work, 2‐[(E)‐(3‐hydroxynaphthalen‐2‐yl)diazenyl]benzoic acid, an azo chromophoric system was prepared and incorporated onto carbohydrates such as starch and cellulose by dicyclohexylcarbodiimide coupling. The products were characterized by UV‐visible, fluorescence, FT‐IR and NMR spectroscopic methods. The results of the studies show that incorporation of the chromophoric system onto the polymeric core enhanced the light absorption, emission and light stabilization properties of the chromophoric system. The light fastening properties of chromophoric system and the carbohydrate‐bound photochromic systems were compared. It shows that light stabilization of the chromophoric system greatly enhanced on attaching to the polymeric core materials. Thermal stability of the chromophoric system also enhanced on attaching to the biopolymeric core systems. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

8.
A convenient one‐pot method for the preparation of (4Z)‐4‐(arylmethylidene)‐5‐ethoxy‐1,3‐oxazolidine‐2‐thiones 2 and 3 from ethyl (2Z)‐3‐aryl‐2‐isothiocyanatoprop‐2‐enoates 1 , which can be easily prepared from ethyl 2‐azidoacetate and aromatic aldehydes, has been developed. Thus, these α‐isothiocyanato α,β‐unsaturated esters were treated with organolithium compounds, including lithium enolates of acetates, to provide 5‐substituted (4Z)‐4‐(arylmethylidene)‐5‐ethoxy‐1,3‐oxazolidine‐2‐thiones, 2 , and 2‐[(4Z)‐(4‐arylmethylidene)‐5‐ethoxy‐2‐thioxo‐1,3‐oxazolidin‐5‐yl]acetates, 3 .  相似文献   

9.
The zinc(II) center in the molecule of [(C23H36N4O3)ZnCl]Cl·H2O is coordinated by four nitrogen atoms of HL (1,3‐bis[2‐[2‐[(4‐methoxybenzyl) amino]ethylamino]]‐2‐propanol) and one chloro anion. The coordination moieties are connected by hydrogen bonds to form a one‐dimensional structure. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

10.
A series of tributyltin(IV) complexes of 2‐[(E)‐2‐(3‐formyl‐4‐hydroxyphenyl)‐1‐diazenyl]benzoic acid and 4‐[((E)‐1‐{2‐hydroxy‐5‐[(E)‐2‐(2‐carboxyphenyl)‐1‐diazenyl]phenyl}methylidene)amino]aryls have been investigated by electrospray mass spectrometry (ESI‐MS) and tandem mass spectrometry (MSn) techniques. The assignments are facilitated by agreement between observed and calculated isotopic patterns and MSn studies. Single‐crystal X‐ray crystallography of (Bu3Sn[O2CC6H4{N?N(C6H3‐4‐OH(C(H)?NC6H4OCH3‐4))}‐o])n reveals a polymeric structure. Toxicity studies of the tributyltin(IV) complexes of the 4‐[((E)‐1‐{2‐hydroxy‐5‐[(E)‐2‐(2‐carboxyphenyl)‐1‐diazenyl]phenyl}methylidene)amino]aryls on the second larval instar of the Aedes aegypti and Anopheles stephensi mosquito larvae are also reported. The LC50 values indicate that the complexes are effective larvicides, which range from a low of 0.36 ppm to a high of 0.69 ppm against the Ae. aegypti larvae and between 0.82 and 1.17 ppm against the An. stephensi larvae. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

11.
A series of novel 5‐alkyl(aryl)‐3‐[(3‐trifluoromethyl)anilino]‐4,5‐dihydro‐1H‐pyrazolo[4,3‐d]pyrimidin‐4‐imines were designed and synthesized by the multistep reactions. 1 reacted with 3‐(trifluoromethyl)aniline to obtain N,S‐acetals 2 in the presence of 10 mol% DBU. 2 reacted with hydrazine to form 5‐amino‐3‐[(3‐trifluoromethyl)anilino]‐1H‐pyrazol‐4‐ nitrile 3 , the target compounds 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i , 5j , 5k , 5l , 5m were obtained by the reaction of 3 with triethyl orthoformate followed by the cyclization of 4 with various amines. Their structures were confirmed by IR, 1H NMR, EI‐MS, and elemental analyses. The preliminary bioassay indicated that some of them displayed moderate herbicidal activity against dicotyledonous weed Brassica campestris L at the concentration of 100 mg/L. For example, compounds 5f , 5g , 5h , and 5j possessed 60.1%, 63.4%, 67.1%, and 61.3% inhibition against Brassica campestris L at the concentration of 100 mg/L.  相似文献   

12.
The unsymmetrical N‐heterocyclic ligand 1‐[(benzotriazol‐1‐yl)methyl]‐1H‐1,3‐imidazole (bmi) has three potential N‐atom donors and can act in monodentate or bridging coordination modes in the construction of complexes. In addition, the bmi ligand can adopt different coordination conformations, resulting in complexes with different structures due to the presence of the flexible methylene spacer. Two new complexes, namely bis{1‐[(benzotriazol‐1‐yl)methyl]‐1H‐1,3‐imidazole‐κN 3}dibromidomercury(II), [HgBr2(C10H9N5)2], and bis{1‐[(benzotriazol‐1‐yl)methyl]‐1H‐1,3‐imidazole‐κN 3}diiodidomercury(II), [HgI2(C10H9N5)2], have been synthesized through the self‐assembly of bmi with HgBr2 or HgI2. Single‐crystal X‐ray diffraction shows that both complexes are mononuclear structures, in which the bmi ligands coordinate to the HgII ions in monodentate modes. In the solid state, both complexes display three‐dimensional networks formed by a combination of hydrogen bonds and π–π interactions. The IR spectra and PXRD patterns of both complexes have also been recorded.  相似文献   

13.
Three ternary rare earth [NdIII ( 1 ), SmIII ( 2 ) and YIII ( 3 )] complexes based on 3‐[(4,6‐dimethyl‐2‐pyrimidinyl)thio]‐propanoic acid (HL) and 1,10‐phenanthroline (Phen) were synthesized and characterized by IR and UV/Vis spectroscopy, TGA, and single‐crystal X‐ray diffraction. The crystal structures showed that complexes 1 – 3 contain dinuclear rare earth units bridged by four propionate groups and are of general formula [REL3(Phen)]2 · nH2O (for 1 and 2 : n = 2; for 3 : n = 0). All rare earth ions are nine‐coordinate with distorted mono‐capped square antiprismatic coordination polyhedra. Complex 1 crystallizes in the monoclinic system, space group P21/c with a = 16.241(7) Å, b = 16.095(7) Å, c = 19.169(6) Å, β = 121.48(2)°. Complex 2 crystallizes in the monoclinic system, space group P21/c with a = 16.187(5) Å, b = 16.045(4) Å, c = 19.001(4) Å, β = 120.956(18)°. Complex 3 crystallizes in the triclinic system, space group P1 with a = 11.390(6) Å, b = 13.636(6) Å, c = 15.958(7) Å, α = 72.310(17)°, β = 77.548(15)°, γ = 78.288(16)°. The antioxidant activity test shows that all complexes own higher antioxidant activity than free ligands.  相似文献   

14.
Kinetic measurements for the thermal rearrangement of 2,2‐diphenyl‐1‐[(E)‐styryl]cyclopropane ( 22a ) to 3,4,4‐triphenylcyclopent‐1‐ene ( 23a ) in decalin furnished ΔH =31.0±1.2 kcal mol?1 and ΔS =?6.0±2.6 e.u. The lowering of ΔH by 20 kcal mol?1, compared with the rearrangement of the vinylcyclopropane parent, is ascribed to the stabilization of a transition structure (TS) with allylic diradical character. The racemization of (+)‐(S)‐ 22a proceeds with ΔH =28.2±0.8 kcal mol?1 and ΔS =?5±2 e.u., and is at 150° 106 times faster than the rearrangement. Seven further 1‐(2‐arylethenyl)‐2,2‐diphenylcyclopropanes 22 , (E)‐ and (Z)‐isomers, were synthesized and characterized. The (E)‐compounds showed only modest substituent influence in their krac (at 119.4°) and kisom (at 159.3°) values. The lack of solvent dependence of rate opposes charge separation in the TS, but a linear relation of log krac with log p.r.f., i.e., partial rate factors of radical phenylations of ArH, agrees with a diradical TS. The ring‐opening of the preponderant s‐trans‐conformation of 22 gives rise to the 1‐exo‐phenylallyl radical 26 that bears the diphenylethyl radical in 3‐exo‐position, and is responsible for racemization. The 1‐exo‐3‐endo‐substituted allylic diradical 27 arises from the minor s‐gauche‐conformation of 22 and is capable of closing the three‐ or the five‐membered ring, 22 or 23 , respectively. The discussion centers on the question whether the allylic diradical is an intermediate or merely a TS. Quantum‐chemical calculations by Houk et al. (1997) for the parent vinylcyclopropane reveal the lack of an intermediate. Can the conjugation of the allylic diradical with three Ph groups carve the well of an intermediate?  相似文献   

15.
A computational study on the rearrangement of 2,2‐diphenyl‐1‐[(E)‐2‐phenylethenyl]cyclopropane ( 1 ) is presented, using density functional theory (DFT), (U)B3LYP with the 6‐31G* basis set (DFT1) and (U)M05‐2X with the 6‐311+G** basis set (DFT2). In agreement with a biradical character of the transition structure (TS) or intermediate, the potential‐energy hypersurface is lowered by the influence of three conjugated Ph groups. Surprisingly, two conformations of the geminal diphenyl group (different twist angles) induce two different minimum‐energy pathways for the rearrangement. Independent of the functional used, the first hypersurface harbors true biradical intermediates, whereas the second energy surface is a flat, slightly ascending slope from the starting material to the TS. The functional (U)M05‐2X with the basis set 6‐311+G** provides realistic energies which seem to be close to experiment. The activation energy for racemization of enantiomers of 1 is lower than that of rearrangement by 2.5 kcal mol?1, in agreement with experiment.  相似文献   

16.
5‐(2‐Cyanoethyl)‐1,1′‐biphenyl‐2‐carboxylates were prepared by regioselective formal [3+3] cyclocondensations of 1,3‐bis[(trimethylsilyl)oxy]buta‐1,3‐dienes.  相似文献   

17.
Homopolymers of 2‐(trimethylsiloxy)ethyl methacrylate of degrees of polymerization from 5 to 50 were synthesized by group transfer polymerization in tetrahydrofuran (THF) using 1‐methoxy‐1‐(trimethylsiloxy)‐2‐methyl propene as the initiator and tetrabutylammonium bibenzoate as the catalyst. These polymers were first converted to poly[2‐(hydroxy)ethyl methacrylate]s by removal of the trimethylsilyl‐protecting groups by acidic hydrolysis, and subsequently transformed to poly{2‐[(3,5‐dinitrobenzoyl)oxy]ethyl methacrylate}s by reaction with 3,5‐dinitrobenzoyl chloride in the presence of triethylamine. Gel permeation chromatography in THF and proton nuclear magnetic resonance (1H NMR) spectroscopy in CDCl3 and d6 dimethyl sulfoxide were used to characterize the polymers in terms of their molecular weight and composition. The molecular weights were found to be close to the values expected from the polymerization stoichiometry and the molecular weight distributions were narrow, with polydispersity indices around 1.1. The hydrolysis and reesterification steps were found to be almost quantitative for all polymers. Differential scanning calorimetry and thermal gravimetric analysis were also employed to measure the glass transition temperatures (Tg 's) and decomposition temperatures, which were determined to be approximately 80 and 320 °C, respectively. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1457–1465, 2000  相似文献   

18.
A series of novel 6‐[(1,3,4‐thiadiazol‐2‐yl)sulfanyl]‐7‐phenylpyrazolo[1,5‐a]pyrimidines, 5‐phenyl‐6‐[(1,3,4‐thiadiazol‐2‐yl)sulfanyl]imidazo[1,2‐a]pyrimidines, and 2‐phenyl‐3‐[(1,3,4‐thiadiazol‐2‐yl)sulfanyl]pyrimido[1,2‐a]benzimidazoles have been synthesized in four steps starting with 2‐hydroxyacetophenone. The intermediate 3‐[(1,3,4‐thiadiazol‐2‐yl)sulfanyl]‐4H‐1‐benzopyran‐4‐ones reacted with pyrazol‐3‐amines, 5‐methylpyrazol‐3‐amine, and 1H‐imidazol‐2‐amine, 1H‐benzimidazol‐2‐amine via a cyclocondensation to give the title compounds in the presence of MeONa as base, respectively. The approach affords the target compounds in acceptable‐to‐good yields. The new compounds were characterized by their IR, NMR, and HR mass spectra.  相似文献   

19.
Eleven novel 5‐methyl‐2‐[(un)substituted phenyl]‐4‐{4,5‐dihydro‐3‐[(un)substituted phenyl]‐5‐(1,2,3,4‐tetrahydroisoquinoline‐2‐yl)pyrazol‐1‐yl}‐oxazole derivatives were synthesized and characterized by elemental analysis, ESI‐MS, 1H NMR and 13C NMR. All of the compounds have been screened for their antiproliferative activities against PC‐3 cell (human prostate cancer) and A431 cell (human epidermoid carcinoma cancer) lines in vitro. The results revealed that compounds 4g , 4j and 4k exhibited the strong inhibitory activities against the PC‐3 cell lines (with IC50 values of 2.8±0.11, 3.1±0.10 and 3.0±0.06 μg/mL, respectively).  相似文献   

20.
《中国化学》2017,35(7):1133-1140
The novel fungicidal agents, (E )‐5‐[1‐(2‐oxo‐1‐oxaspiro[4,5]dec/non‐3‐en‐3‐yl)ethylidene]‐2‐aminoimidazolin‐ 4‐one derivatives, were designed and synthesized in moderate to excellent yields in four steps using α ‐hydroxyketone and diketene as raw materials and characterized by HR‐ESI‐MS , 1H NMR and X‐ray diffraction. The preliminary bioassay showed that some of these compounds, such as 5e , 6a , 6e , and 7 h exhibit 87.8%, 91.3%, 89.9% and 87.8% inhibition rates against Sclerotinia scleotiorum , 3b , 3c , 4c and 7 h exhibit 96.4%, 92.5%, 90.3% and 76.9% inhibition rates against Phytophthora capsici at the concentration of 50 µg/mL , respectively. These compounds exhibited significant fungicidal activities against S. scleotiorum and P. capsici with EC50 values of 2.56–11.60 µg/mL , and compounds 6e and 7 h exhibited weak inhibition against the spore germination of S. scleotiorum , while the spore germination of P. capsici was strongly inhibited by compound 7 h solution. Scanning electron microscopy (SEM ) and transmission electron microscopy (TEM ) observation indicated that compound 7 h had a significant impact on the structure and function of the hyphal cell wall of P. capsici mycelium.  相似文献   

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