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1.
李和平  郭灿城 《有机化学》2000,20(5):830-832
在还原剂维生素C存在下,将4-氨基苯甲醛与吡咯在丙酸中缩合得到5,10,15,20-中位-四(4-氨基苯基)卟吩,操作简单,产率高于文献方法。  相似文献   

2.
The Knoevenagel condensations of 5-[3-(trifluoromethyl)phenyl]furan-2-carbaldehyde with seven compounds containing an active methyl or methylene group have been studied. The compounds used were: methyl 2-cyanoacetate, malononitrile, 2-furylacetonitrile, acetophenone, 2-thioxo-1,3-thiazolidin-4-one (rhodanine), 5,5-dimethylcyclohexane-1,3-dione (dimedone), and methyl 2-azidoacetate. The effect of microwave irradiation on the condensation reactions was studied and compared with “’classical”’ conditions. Thermolysis of methyl 2-azido-3-{5-[3-(trifluoromethyl)phenyl]-2-furyl}propenoate afforded methyl 2-[3-(trifluoromethyl)phenyl)]-4H-furo[3,2-b]pyrrole-5-carboxylate. (2E)-3-{ 5-[3-(Trifluoromethyl)phenyl]-2-furyl}propenoic acid was converted to the corresponding azide, which was cyclized on heating into 2-[3-(trifluoromethyl)phenyl)]-4,5-dihydrofuro[3,2-c]pyridin-4-one. The latter after successive action of POCl3 and NH2NH2-Pd/C gave 2-[3-(trifluoromethyl)-phenyl]furo[3,2-c]pyridine. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 825–831, June, 2006.  相似文献   

3.
A new cardo diamine monomer, 5,5-bis[4-(4-aminophenoxy)phenyl]-4,7-methanohexahydroindane (II), was prepared in two steps with high yield. The monomer was reacted with six different aromatic tetracarboxylic dianhydrides in N,N-dimethylacetamide (DMAc) to obtain the corresponding cardo polyimides via the poly(amic acid) precursors and thermal or chemical imidization. All the poly(amic acid)s could be cast from their DMAc solutions and thermally converted into transparent, flexible, and tough polyimide films which were further characterized by x-ray and mechanical analysis. All of the polymers were amorphous and the polyimide films had a tensile strength range of 89–123 MPa, an elongation at break range of 6–10%, and a tensile modulus range of 1.9–2.5 GPa. Polymers Vc, Ve, and Vf exhibited good solubility in a variety of solvents such as N-methyl-2-pyrrolidinone (NMP), DMAc, N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), pyridine, γ-butyrolactone, and even in tetrahydrofuran and chloroform. These polyimides showed glass-transition temperatures between 274 and 299°C and decomposition temperatures at 10% mass loss temperatures ranging from 490 to 521°C and 499 to 532°C in nitrogen and air atmospheres, respectively. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2815–2821, 1999  相似文献   

4.
5-碘[杯(4)芳烃偶氮]氨基喹啉光度法测钯   总被引:1,自引:0,他引:1  
合成了新试剂5 碘[杯(4)芳烃偶氮]氨基喹啉(ICAQ),并研究了该试剂与钯显色反应条件。结果表明,在pH10.2~11.0的Na2CO3 NaHCO3缓冲介质中,在TritonX 100存在下,试剂与钯发生显色反应,生成1∶1稳定络合物。建立了测定钯的光度法新体系,λmax=625nm,ε=1.42×105L·mol-1·cm-1,钯质量浓度在0~0 80μg/mL内符合比尔定律。方法用于钯催化剂中钯的测定,结果与原子吸收法相符,平行6次测定的RSD在2.5%~3.0%。  相似文献   

5.
基于卟啉对癌细胞的特殊亲和作用和哌嗪化合物的抗肿瘤、抗病毒作用,设计并合成了具有哌嗪结构的新型卟啉化合物5,10,15,20-四[4-(4'-乙基哌嗪基)苯基]卟啉(TEPPPH2),其结构经UV-Vis, 元素分析,1H NMR等手段证明。采用UV-Vis光谱和荧光光谱研究了TEPPPH2和小牛胸腺DNA 的相互作用模式和结合机理。实验发现,TEPPPH2能嵌入到DNA的碱基对中,1个小牛胸腺DNA分子对TEPPPH2分子的最大结合数n约为88,结合常数为8.4×106mol•L-1 。TEPPPH2与DNA的结合数和结合常数大于已知的四(4-N-甲基吡啶基)卟啉和Ca/sal-his、Ni/sal–aln型席夫碱抗癌药物。  相似文献   

6.
3,3-Bis[4-(4-aminophenoxy)phenyl]phthalide ( II ) was used as a monomer with various aromatic dicarboxylic acids and dianhydrides to synthesize polyamides and polyimides, respectively. The diamine II was derived by a nucleophilic substitution of phenolphthalein with p-chloronitrobenzene in the presence of K2CO3. Polyamides IV a-g having inherent viscosities of 0.77–2.46 dL/g were prepared by the direct polycondensation of diamine II with diacids III a-g using triphenyl phosphite and pyridine as condensing agents. The polyamides were readily soluble in a variety of solvents such as N, N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), and N-methyl-2-pyrrolidinone (NMP) and afforded transparent and flexible films from the polymer solutions. These polymers had glass transition temperatures (Tgs) in the 227–307°C range and 10% weight loss temperatures occurred up to 450°C. Polyimides VI a-e based on diamine II and various aromatic dianhydrides V a-e were synthesized by the two-stage procedure that included ring-opening, followed by thermal or chemical conversion to polyimides. Most of the polyimides obtained by chemical cyclodehydration procedure were found to soluble in DMF, NMP, o-chlorophenol, and m-cresol. The Tgs of these polyimides were in the 260–328°C range and showed almost no weight loss up to 500°C under air and nitrogen atmosphere. © 1994 John Wiley & Sons, Inc.  相似文献   

7.
采用时间分辨荧光光谱等手段研究了手性探针分子L-[4-(1-芘基)]丁酰基苯丙氨酸(PLP)与溶菌酶(Lys)、牛血清白蛋白(BSA)和人血清白蛋白(HSA)的结合过程及机理,探讨了三氯六氨合钴(CoHA)对不同复合体系内芘基的荧光猝灭作用.结果表明,PLP在与血清白蛋白的结合过程中是以芘基插入到血清白蛋白疏水空腔中的方式与蛋白质结合的;而PLP与Lys的结合部位处在其表面的疏水部分.  相似文献   

8.
A novel fluorinated diamine monomer, 9,9-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]fluorene (II) was prepared via the nucleophilic substitution reaction of 2-chloro-5-nitrobenzotrifluoride with 9,9-bis(4-hydroxyphenyl)fluorene in the presence of potassium carbonate, followed by catalytic reduction with hydrazine and Pd/C. Polyimides V were synthesized from diamine II and various aromatic dianhydrides III a-f via thermal imidization. These polymers had inherent viscosities ranging from 0.84 to 1.03 dL/g and were soluble in a variety of organic solvents such as NMP, DMAc, DMF, and DMSO, and some could even be dissolved in less polar solvents such as m-cresol, pyridine, and dioxane. Polyimide films V a-f had tensile strengths of 85–105 MPa, elongations to break of 7–9%, and initial moduli of 2.13–2.42 GPa. The glass transition temperature of these polymers were in the range of 277–331 °C, their 10% weight loss temperatures were in the range of 539–594 °C in nitrogen and above 544 °C in air, and their char yields at 800 °C in nitrogen ranged between 55–65 wt%. Compared with nonfluorinated polyimides VI, V showed better solubility and lower color intensity. Low dielectric constants (2.68–2.85 at 1 MHz) and low moisture absorptions (0.12–0.24 wt%) were also observed. In particular, V c-f afforded lightly-colored films, which had cutoff wavelengths lower than 385 nm and b* values ranging from 6 to 22.  相似文献   

9.
付二霞  曹高  石磊  胡艾希 《结构化学》2013,32(5):709-713
The title compound 2(C22H28N+O3)·H2O·2Cl-was synthesized by the reaction of 2-bromo-1-[4-(benzyloxy)phenyl]-1-pentone with 2,2'-azanediyldiethanol. The crystal determined by X-ray diffraction analysis belongs to the monoclinic system, space group Pc with a = 18.312(3), b = 14.838(3), c = 7.6227(14) , β = 97.981(4)°, Z = 2, Mr = 797.82, V = 2051.1(6) 3, Dc = 1.292 g/cm3, S = 0.956, μ = 0.21 mm-1, F(000) = 852, the final R = 0.0625 and wR = 0.1428 for 5683 observed reflections (Ⅰ > 2σ(Ⅰ)). Flack parameter is 0.10(9). The title compound is composed by four non-coplanar ring systems, two benzenes and two morpholines. One morpholine ring (C(3)-C(4)-N(1)-C(1)-C(2)-O(1)) forms a chair conformation, while the other (C(4)-C(3)-O(2)-C(6)-C(5)-N(1)) assumes a boat conformation. X-ray crystal structure displays extensive N-H…Cl and O-H…Cl intermolecular hydrogen bonds. The preliminary antidepressant activity test indicates that the inhibition ratio of SERT (5-HT Transporter) was 35.9% at the dosage of 10.0 mg/L.  相似文献   

10.
9,9-Bis[4-(p-aminophenoxy)phenyl]fluorene ( II ) was used as a monomer with various aromatic dicarboxylic acids and tetracarboxylic dianhydrides to synthesize polyamides and polyimides, respectively. The diamine II was derived by a nucleophilic substitution of 9,9-bis(4-hydroxyphenyl)fluorene with p-chloronitrobenzene in the presence of K2CO3 and then hydro-reduced. Polyamides IV a-g having inherent viscosities of 0.73–1.39 dL/g were prepared by the direct polycondensation of the diamine II with various aromatic diacids using triphenyl phosphite and pyridine as condensing agents. All the aromatic polyamides were amorphous and readily soluble in various polar solvents such as N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, and N-methyl-2-pyrrolidone. Transparent and flexible films of these polymers could be cast from the DMAc solutions. These aromatic polyamides had glass transition temperatures in the range of 283–309°C and 10% weight loss occurred up to 460°C. The polyimides were synthesized from diamine II and various aromatic dianhydrides via the two-stage procedure that included ring-opening poly-addition in DMAc to give poly(amic acid)s, followed by thermal or chemical conversion to polyimides. The poly(amic acid)s had inherent viscosities of 0.62–1.78 dL/g, depending on the dianhydrides. Most of the aromatic polyimides obtained by chemical cyclization were found to be soluble in NMP. These polyimides showed almost no weight loss up to 500°C in air or nitrogen atmosphere. © 1993 John Wiley & Sons, Inc.  相似文献   

11.
A new dialdehyde 1,1-bis[4-(4-benzaldehyde oxy)-3-methyl phenyl] cyclopentane (BBMPC) was synthesized starting from cyclopentanone and O-cresol to give 1,1-bis(4-hydroxy-3-methyl phenyl)cyclopentane (BHMPC); followed by reaction with 4-fluorobenzaldehyde in N, N-dimethyl formamide (DMF), containing anhydrous potassium carbonate. New series of poly(ether-azomethine)s were synthesized from (BBMPC) with different diamines such as 4,4′- diamino diphenyl ether (ODA); 4,4′-diaminodiphenyl methane (MDA); 4-aminophenyl sulfone (SDA); p-phenylene diamines (p-PDA), etc. in N, N’- dimethyl acetamide (DMAc) with 5 wt% LiCl by the solution polycondensation method. Inherent viscosities of these polymers were in the range 0.20 to 0.38 dL/g indicating formation of moderate molecular weights. These polymers exhibited good solubility in various polar aprotic solvents such as N-methyl-2-pyrrolidone (NMP), DMAc, DMF, etc. However some polymers showed partial solubility in DMF and DMAc. X-Ray diffraction pattern of polymers showed amorphous nature. Thermal stability was assessed by 10% weight loss temperature and the degradation temperature of the resultant polymers falls in the ranges from 444-501°C in nitrogen. The glass transition temperature was in the range of 155-205°C. The structure-property correlation among these polyazomethines were studied; in view of their potential applications as high performance polymers.  相似文献   

12.
N-[4-(磺酰胺)苯基]丙烯酰胺(ASPAA)单体可以均聚或与其它单体共聚合成具有药理活性的聚合物,制成水溶性、毒副作用小、具有缓释作用的大分子药物.同时,由于磺酰胺基具有一定的碱溶性,ASPAA与丙烯酸酯类等单体的共聚物可用于制备可碱显影、显影宽容度和耐印力等性能良好的平印、计算机直接制版版材.有关ASPAA与其它单体共聚的竞聚率还鲜见报道.本文在合成ASPAA单体的基础上,对ASPAA/丙烯腈和ASPAA/甲基丙烯酸甲酯共聚的竞聚率进行了研究。  相似文献   

13.
A new kink diamine with trifluoromethyl group on either side, bis[4-(2-trifluoromethyl-4-aminophenoxy)phenyl]diphenylmethane (BTFAPDM) , was reacted with various aromatic dianhydrides to prepare polyimides via poly (amic acid) precursors followed by thermal or chemical imidization. Polyimides were prepared using 3,3′, 4,4′-biphenyltetracarboxylic dianhydride(1), 4,4′-oxydiphthalic anhydride(2), 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (3), 4,4′-sulfonyldiphthalic anhydride(4), and 4,4′-hexafluoroisopropylidene-diphathalic anhydride(5). The fluoro-polyimides exhibited low dielectric constants between 2.46 and 2.98, light color, and excellent high solubility. They exhibited glass transition temperatures between 227 and 253°C, and possessed a coefficient of thermal expansion (CTE) of 60-88 ppm/°C. Polymers PI-2, PI-3, PI-4, PI-5 showed excellent solubility in the organic solvents: N-methyl-2-pyrrolidinone (NMP), N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), pyridkie and tetrahydrofuran (THF). Inherent viscosity of the polyimides were found to range between 0.58 and 0.72 dLg-1. Thermogravimetric analysis of the polyimides revealed a high thermal stability decomposition temperature in excess of 500°C in nitrogen. Temperature at 10 % weight loss was found to be in the range 506-563°C and 498-557°C in nitrogen and air, respectively. The polyimide films had a tensile strength in the range 75-87 MPa; tensile modulus, 1.5-2.2 GPa; and elongation at break, 6-7%.  相似文献   

14.
Alternate poly(amide-imide) [P(A-alt-I)] was synthesized from two aromatic diamines and trimellitic anhydride (TMA). When the diamine was 2,2-bis[4-(3-aminophenoxy)phenyl]sulfone (BAPS), the resulted P(A-alt-I) was found to be of light color. Specifically, when BAPS was located between two amide groups in the P(A-alt-I) chain, the P(A-alt-I) was almost colorless. A series of P(A-alt-I)s (Series III) containing BAPS was synthesized through direct polycondensation of an aromatic dicarboxylic acid prepared from various aromatic diamines and TMA, as well as BAPS. Polymers of Series III were much lighter in color than those of the isomeric series (BAPS was located between two imide group). The series of P(A-alt-I)s III had inherent viscosities ranging 0.69–1.35 dL/g and good solubility in various solvents. The tensile strengths, elongations to break, and initial moduli of the films were 72–107 MPa, 7–12% and 1.93–2.39 GPa, respectively, and most of the films had no yielding. Polymers of Series III had glass transition temperatures 210–272°C and 10% weight loss temperatures in nitrogen 518–545°C, indicating excellent thermal stability. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2421–2428, 1999  相似文献   

15.
用3,5—diBr—PAMB光度法测定微量铑的研究   总被引:4,自引:0,他引:4  
  相似文献   

16.
基于卟啉对癌细胞的特殊亲和作用和吡咯烷化合物的抗肿瘤及抗癌活性,设计并合成了具有吡咯烷结构的新型卟啉化合物--meso-5,10,15,20-四[4-(N-吡咯烷基)苯基]卟啉(TBPPH2),利用荧光光度法和紫外-可见分光光度法研究了TBPPH2与牛血清白蛋白(BSA)的相互作用.实验发现,TBPPH2利用疏水作用力进入BSA的疏水性腔,与BSA形成配合物并引起BSA的静态荧光猝灭.在TBPPH2与BSA的相互作用过程中,TBPPH2与BSA以摩尔比1∶1牢固结合,TBPPH2与BSA分子中色氨酸间的最近距离r=2.4nm.反应平衡常数KA=2.51×104L/mol,反应熵变ΔS=84.18J/(mol·K),TBPPH2与BSA的结合常数KB=5.13×105L/mol.研究结果表明,吡咯烷基卟啉可能成为一类新型的抗肿瘤及抗病毒药物.  相似文献   

17.
A dicarboxylic acid ( I ) was prepared from the condensation of 9,9-bis[4-(4-aminophenoxy) phenyl] fluorene and trimellitic anhydride. A new family of poly(amide-imide)s having inherent viscosities of 0.75-1.04 dL/g was prepared by the triphenyl phosphite activated polycondensation from the diimide-diacid I with various aromatic diamines in a medium consisting of N-methyl-2-pyrrolidone (NMP), pyridine, and calcium chloride. Most of the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All the soluble poly(amide-imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 262–325°C and the 10% weight loss temperatures were above 525°C in air. © 1994 John Wiley & Sons, Inc.  相似文献   

18.
对-二甲氨基苯甲醛和苯基氨基硫脲缩合反应生成1-[4-(二甲氨基)苯亚甲基氨基]-4-苯基硫脲(DMB), 产物能从溶液中析出单一手性对映体晶体. 用单晶X射线衍射技术测定了它的绝对构型, 晶体属正交晶系, P212121空间群, a=0.7870(2) nm, b=1.1560(2) nm, c=1.6668(3) nm, V=1.5164(5) nm3, Z=4, Dc=1.307 g/cm3, F(000)=632, μ=0.213 mm-1, 2557个可观测点[I>2s(I)]精修的最终残差因子: R=0.0409, wR=0.1061, Flack参数为0.00(9), 能够确定绝对构型. 化合物的晶体结构和大宗粉末样品的固体圆二色谱表明化合物在结晶过程中发生单一对映体的手性堆积.  相似文献   

19.
The corresponding 1-(2-quinoxalyl)-, 1-[3,5-di(trifluoromethyl)phenyl]-, and 1-ethoxycarbonyl-3-methyl-4-oxo-4,5,6,7-tetrahydroindazoles have been obtained from reactions of 2-acetyl-1,3-cyclohexanedione, its 5,5-dimethyl and 5-(2-furyl) derivatives, with 2-hydrazinoquinoxaline, 3,5-di(trifluoromethyl)phenylhydrazine, and ethoxycarbonylhydrazine. On interaction with ethoxycarbonylhydrazine the intermediate 2-[1-(-ethoxycarbonyl)hydrazino]ethylidene-1,3-cyclohexanediones were also isolated. From the potassium salt of 2-formyldimedone and 2-carboxyphenylhydrazine hydrochloride, 2-(2-carboxyphenyl)hydrazinomethylene-5,5-dimethyl-1,3-cyclohexanedione was obtained, the cyclization of which in ethanol in the presence of HCl led to 1-(2-carboxyphenyl)- and 1-(2-ethoxycarbonylphenyl)-6,6-dimethyl-4-oxo-4,5,6,7-tetrahydroindazole.  相似文献   

20.
We have used semiempirical calculations (PM3, MNDOd) to show that the parabolic dependence of the rate constants (kobs, s−1) on the picryl iodide (PicI) concentration in the reaction of quaternization of 4-[4-(dimethylamino)styryl]pyridine (DASP) in acetonitrile is due to formation of an inactive σ1,3 adduct from DASP and PicI. Formation of the σ1,1 adduct is the rate-limiting step of the SNAr substitution. __________ Translated from Teoreticheskaya i Eksperimental'naya Khimiya, Vol. 41, No. 4, pp. 242–246, July–August, 2005.  相似文献   

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