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1.
水溶性锌卟啉配合物的合成、表征及其与CTDNA的作用   总被引:7,自引:3,他引:4  
合成了5,10,15,20-四[4-(3'-丙氧基吡啶溴化盐)苯基]卟啉(TPPBr)及其锌卟啉配合物TPPBr(Zn),用红外光谱、核磁共振和紫外光谱进行了表征.利用紫外-可见光谱、荧光光谱、圆二色谱和黏度实验研究了TPPBr(Zn)与小牛胸腺DNA(CTDNA)的相互作用,并计算了TPPBr(Zn)与CTDNA作用的表观键合常数为2.64×105L/mol.进而证明了TPPBr(Zn)与CTDNA以外部自堆积和静电结合的混合模式作用.  相似文献   

2.
采用紫外-可见分光光度法研究了溴代卟啉(H2TPPBrx)在N,N-二甲基甲酰胺(DMF)中的吸收光谱性质,并测定了其在非水溶剂DMF中与HClO4反应的质子化常数。结果表明H2TPP,H2TPPBr2在DMF溶剂中与高氯酸反应得到两个质子生成[H4TPP]2 和[H4TPPBrx]2 ,而H2TPPBr3,H2TPPBr4只能得到一个质子生成[H4TPPBrx] 和[H4TPPBrx] ,其质子化常数分别为:lgK1=3.28,lgK2=2.86,lgK3=2.16,lgK4=1.93。  相似文献   

3.
<正> C100H78, (A: C36H28, B: C28H22) Mr = 1279. 74, monoclinic, P21/a, a=17. 282(3), b=10. 669(4), c= 19, 927(3) A , β =102. 99(1)°,V = 3580. 1(2) A3, Z=2, μ(MoKα) = 0. 623cm-1, F(000) = 1356, Dc=1. 187g/cm3, room temperature. The final R=0. 084, Rw = 0. 086 for 1255 independent observed reflections (I≥3σ(I)). Owing to the existence of 1,6,7, 8-Tetraphenyl (3,4-benzo)-bicyclo[4, 2, 0]octa-7-ene(A) , cis, cts-1, 2, 3, 4-Tetraphenylbutadiene (B) in A2B can take the different conformation from the one in the pure B crystal. The reason of the formation of this molecular compound crystal is put forward.  相似文献   

4.
丁维钰  魏嘉  浦家齐 《化学学报》1987,45(10):1035-1038
The reaction of benzoylmethylenetriphenylphosphorane (I) and -arsorane (II) with RCYCCNC:C2F5, n-C3F7) took place smoothly. At room temperature, Ph3P:C(CN)CR:CHBz were formed from phosphonium ylide I in high yield and mixtures of Ph3As:C(CN)CR:CHBz and Ph3As:CBaCR:CHCN were formed from arsonium ylide II and they could be separated by chromatog. and the total yields were about 95%. At low temperature (-78癈), Ph3M:CBzCR:CHCN (M = P, A5) were formed as the sole products in moderate yield.  相似文献   

5.
IntroductionInl99o,Sutteretal.preParedthefirstorganicphotorefrachvecrystalsCoANP:TCNQbydoPingnon-linearopticalcrystalCOANPwithTCNQ.l1]Sincethen,quitealotofattentionwasdirectedintothisfield.[2'3]TherearetWobasicprerequisitesforamaterialtohavephotorefractiveeffectfhavingthesecondorderoPticalnon-linearityandthephotoconductivitythatiscloselyrelatedwithphotoinducedinermolecularchargetransfer.RecentlyitwasrePOrtedthatHEC(9-hydroxyethylcarbazole)ethibitedinterestingnon-linearityandphotocon…  相似文献   

6.
IntroductionUptonow,therehavebeenreportsonthemaintypicalhighcriticaltemper-aturesuperconducting(HTS)systems:BiSrCaCuO,T1BaCaCuOandXBaCuO(XdenotesheavyandraremetalssuchasY,Nd,Dy).IthasalsobeenreportedthatdopingPb,Mo,Al,W,Ti,SbandFetc.insuperconductorscanmaintainTc.Thestructuresareallioniccrystalswhicharecomposedofrare(orheavy)metalelementsandBaCuO,BaCaCuO(orSrCuO,SrCaCuO)components.Thecrystalce1lunitsofTlBaCaCuO,BiSrCaCuOandXBaCuO(X=Y,Nd,DY)su-perconductorsareshowninFi…  相似文献   

7.
采用相图计算(CALPHAD:Calculation of phase diagrams)方法对Zr-X(X=Li,Na,K,Sc,Hf)5个二元体系进行了相图热力学研究.基于实验数据,通过热力学优化计算获得了一套描述液相及(αZr),(βZr),(Li),(Na),(K),(αSc),(βSc),(αHf)和(βHf)相的热力学参数.Zr-Li,Zr-Na和Zr-K体系中的气相视为理想气体.与实验相图数据对比发现,本文获得的热力学参数能够准确地描述实验相平衡数据.  相似文献   

8.
李勤瑜  许旋 《物理化学学报》2007,23(12):1875-1880
In order to study the effects of R group on Fe-Hg interactions and 31P chemical shifts, the structures of mononuclear complexes Fe(CO)3(PPh2R)2 (R=pym: 1, fur: 2, py: 3, thi: 4; pym=pyrimidine, fur=furyl, py=pyridine, thi=thiazole) and binuclear complexes [Fe(CO)3(PPh2R)2(HgCl2)] (R=pym: 5, fur: 6, py: 7, thi: 8) were studied by using the density functional theory (DFT) PBE0 method. The 31P chemical shifts were calculated by PBE0-GIAO method. Nature bond orbital (NBO) analyseswere also performed to explain the nature of the Fe-Hg interactions. The conclusions can be drawn as follows: (1) The complexes with nitrogen donor atoms are more stable than those with O or S atoms. The more N atom there are, the higher is the stabilitity of the complex. (2) The Fe-Hg interactions play a dominant role in the stabilities of the complexes. In 5 or 6, there is a σ-bond between Fe and Hg atoms, However, in 7 and 8, the Fe-Hg interations act as σP-Fe→nHg and σC-Fe→nHg delocalization. (3) Through Fe邛Hg interactions, there is charge transfer from R groups towards the P, Fe, and Hg atoms, which increases the electron density on P nucleus in binuclear complexes. As a result, compared with their mononuclear complexes, the 31P chemical shifts in binuclear complexes show some reduction.  相似文献   

9.
<正> C16H13N5S2· (C2H5)3N: Mr = 440. 64, monoclinic, space group C2/c with a = 18.956(7)(?), b = 12. 866(7)(?), c = 20. 830(9)(?) , β=115. 63(3)°; Z=8; V = 4580(7)(?)3; Dc = 1. 278gcm-3; F (000) = 1872, μ= 2. 423cm-1 (MoKa). Final R is 0. 069. C16H13N5S2is non-planar with two rings, a five-member and a six-member with conformations of envelope and twist boat forms respectively, and the two substituted phenyl groups are in equatorial and axial positions.  相似文献   

10.
d,l-a-Tocopherol(vitaminE)isgenerallysynthesizedbycondensingtrimethylhydroquinone(TMHQ)withphytolorisophytolcatatyzedbyvariousBronstedandLex'llisacidssuchasZnCI,-HCI'andAICI;'.Anessentialdisadvantageofthesecatalystsistheirhighconsumption.TheratioofZnCI,toTMHQIsaboLltI(I.Futhertllore.thecatalystsaredifficulttoberecoveredandreused.Recentl}.I.V.Rozhevnikovandco-workers'reportedthatthereactioncouldbecatalyzedbyheteropolyacids(HPA)H:PW,=O.,andH;SiW,=O..,.TheconsumptionoftheseHPAw…  相似文献   

11.
The natural sex pheromone of the yellow rice borer, Scirpophaga incertulas is known to consist of 3 components: 16: Ald (Ⅰ), (Z)-9-16: Ald (Ⅱ) and (Z)-11-16: Ald (Ⅲ) by using single sex pheromone gland technique, high performance capillary CC, GC-MS, EAG, micro-chemical reaction as well as field trapping tests. Analysis of single sex pheromone gland showed that the precise ratio of the 3 components is 18.8 (Ⅰ): 27.1 (Ⅱ): 54.1 (Ⅲ) (%). The septura lure made according to the above precise blending showed strong attractancy in the field trapping tests. Maximun catch of a trap was 45 males/ day in the first generation in Guangxi Zhuang Autonomous Region. The average catch per day was 15.8 males.  相似文献   

12.
IntroductionTheMHg(SCN)4seriesofcrystallinecomplexeshavebeenknowninanalyticalchemistryfortheircharacteristicshapesand..l.,,i.Withthedevelopmentofnon-linearoptics(NLO),thiskindofcoordinationcompoundshavebeendiscoveredtobeusefulasNLOmaterials.In1970s,ItwasreportedthattheN'LOcoefficient(fordoublinginfraredI.064urnNd:YAGlaserbeamtogenerate0.532urngreenlight)ofCdHg(SCN)4wasI.3timesasthatofNLOcrystalLiIO,'.Furthermore,wehaverecentlydiscoveredthattheCdHg(SCN)'crystalcangeneratesecondha…  相似文献   

13.
采用基于密度泛函理论的第一性原理方法系统地研究了Au12M(M=Na,Mg,Al,Si,P,S,Cl)团簇的结构、稳定性和电子性质.对团簇的平均结合能、镶嵌能、垂直离化势、最高占据分子轨道(HOMO)和最低未占据分子轨道(LUMO)的能级差、电荷布居分析、自然键轨道(NBO)进行了计算和讨论.对于Au12M(M=Na,Mg,Al)团簇,它们形成了内含M原子的最稳定的笼状结构.然而对于Au12M(M=Si,P,S,Cl)团簇,它们却形成了以M元素为顶点的稳定锥形结构.在这些团簇中发现Au12S团簇相对是最稳定的,这是由于Au12S团簇形成了稳定的满壳层的电子结构.自然电荷布居分析表明:对于所有的Au12M(M=Na,Mg,Al,Si,P,S,Cl)团簇电荷总是从Au原子转向M原子.自然键轨道和HOMO分析表明Au12M团簇中发生了Au原子的s-d轨道和M原子的p轨道间的杂化现象.  相似文献   

14.
The two crystal structures of C_(17)H_(17),N_2O_2Cl_2PS (NP-8) and C_(17)H_(19)N_2O_2PS (NP-10-Ⅱ) have beendetermined by Patterson method. The crystals belong to monoclinic system with space group of P2_1/aand P2_1/n respectively. There are four molecules in the unit cell. Cell parameters: a = 26.622 (7)A, b = 7.711 (2) A., c = 9.461 (3) A, β = 94.90°(4) and a = 18.879(3) A, b = 10.199 (13) A, c = 8.948(3) A, β= 94.30°(3) for the two cells. After refinement by block diagonal matrix least squares me-thod, R factors are 0.046 for 2971 reflections of NP-8 and 0.076 for 1711 reflections of NP-10-Ⅱ. Referring to molecular structures of NP-8 and NP-10-Ⅱ spectra data have been satisfactorilycxplained. The characteristic features of the structures have been discussed.  相似文献   

15.
A novel copper complex [Cu_2(L)(DMF)_2](1, H_4L =(1 Z,N?Z)-3,5-dibromo-N?-((3,5-dibromo-2-hydroxyphenyl)(hydroxy)methylene)-2-hydroxybenzohydrazonic acid which was synthesized by in-situ oxidation reaction derived from H_2hdb(H_2hdb = 6,6?-((1 E,1?E)-hydrazine-1,2-diylidenebis(methanylylidene)) bis(2,4-dibromophenol)) has been synthesized and characterized by IR, elemental analysis(CHN), TG and single-crystal X-ray diffraction. The single crystal belongs to monoclinic system, space group P21/c with a = 13.538(1), b = 3.912(1), c = 23.778(1) ?, β = 105.232(5)o, Mr = 857.08, V = 1214.9(1) ?~3, Z = 2, Dc = 2.343 g/cm~3, F(000) = 824, μ = 8.375 mm~(–1), R = 0.0566, and w R = 0.1610. Compound 1 displays weak anti-ferromagnetic interactions through a η~1:η~1:η~1:η~1:η~1:η~1:μ_2-L~(4-) bridging mode. Hirshfeld surface analysis revealed that complex 1 was supported mainly by Br···H and H···H intermolecular interactions.  相似文献   

16.
<正> The title com pound (HHOMP) has been synthesized with the pho-toinduced condensation of acetone and pyrrole in the presence of iodoaromatic hydrocarbons, and its molecular and crystal structures have been determined by X-ray analysis. C28H36N4, Mr = 428. 63, triclinic; space group P1; a =10. 165(3), b = 10. 185(2), c=13. 012(3)(?); α=85. 41(2), β=67. 84(2), γ= 89. 75(2)°; V = 1243 (?)3; Z = 2; D = 1. 145g. cm-3; μ= 0. 635cm-1; F (000) = 464. Although the HHOMP molecule twists, it is found that the four nitrogen atoms are still in a plane.  相似文献   

17.
A high performance liquid chromatographic assay has been developed for the simultaneous determination of five water soluble vitamins:thimine, riboflavin, niacin, pyridoxine and folic acid in cereal products and fresh vegetables. Food samples were hydrolyzed in 0.4 mol/L HCl, autoclaved at 120℃ 15 psi for 20 minutes, using a μ-Bondapak column (3.9×300mm, Waters Co.), a mobile phase of methanol-water (30:70) (0.005 mol/L heptanesulfonic acid) and a flow rate of 1.0 ml/min gave the most satisfactory separation of the five water soluble vitamins. A double channel deteetion was used: four vitamins (B_5, folic acid, B_2, B_1) were detected hy UV spectrophotometry (254 nm) first, pyridoxine (B_6) was detected by fluoromelry (EX 290nm, EM 395 nm) afterwards. Detection limits were 2, 5, 5, 2and 5ng, linear ranges were 5-10ng, 5-50ng, 5-40ng, 5-50ng and 10-50ng for B_1, B_2, B_5, B_6 and folic acid respectively. Recoveries were 92-100%(B_5), 51-52% (folio acid), 103—105% (B_2), 99—100% (B_6) and 91.3—102% (B_1) respectively. In comparison with a reference method and checking with food composition tables, very satisfactory results were obtained by this method.  相似文献   

18.
基于剑桥晶体数据库中同配配合物的Sn(Ⅱ)-X和Sn(Ⅳ)-X (X=O,S,N,C,P,As,Se,Te,F,Cl,Br,I)键长数据,采用键价参数B=0.037 nm拟合得到Sn(Ⅱ)-X和Sn(Ⅳ)-X的键价参数R0,这样拟合的经验参数R0中有一些是首次推出.本文所报道的Sn(Ⅱ)-O键基于B=0.037 nm的R0值(0.1956 nm)可适用于多数Sn(Ⅱ)呈各种配位数时的氧化态指定,而文献报道的B=0.055 nm和R0=0.1859 nm主要对于低配位的情况能取得Sn(Ⅱ)原子价态指定的较好结果.本研究证明,进一步研究键价参数对键价和(BVS)计算至关重要的那些可能的因素实乃当务之急.  相似文献   

19.
<正> The structure of 3a-(4-chlorophenyl)-1, 5-diphenyl-3a, 4,5,11-te-trahydrq-1, 2, 4-oxadiazolino [5, 4-d][1, 5] benzothiazepine (C28H21N2OClS) has been determined. The compound crystallizes in triclinic space group P1 with two formula units in a cell of dimensions: a =11. 114(2), b = 11. 673(1), c=10. 435(1) (?), α=98. 42(1), β=118. 69(1),γ = 98. 64(1)° and V = 1136. 2(3)(?)3. The structure was solved by using direct methods and refined by full matrix least-squares. The final crystallographic discrepancy factor is 0. 058 for 2384 observed reflections. The molecular backbone is a tricyclic system : The seven-membered hetero ring in the center is in twisted-boat conformation, and is cis-fused to 1, 2, 4-oxadiazolino ring which is in an envelope form, together with the equilaterally adjoined benzene ring . The compound has a non-planar conjugation system.  相似文献   

20.
基于剑桥晶体数据库中同配配合物的Sn(Ⅱ)―X和Sn(Ⅳ)―X(X=O,S,N,C,P,As,Se,Te,F,Cl,Br,I)键长数据,采用键价参数B=0.037nm拟合得到Sn(Ⅱ)―X和Sn(Ⅳ)―X的键价参数R0,这样拟合的经验参数R0中有一些是首次推出.本文所报道的Sn(Ⅱ)―O键基于B=0.037nm的R0值(0.1956nm)可适用于多数Sn(Ⅱ)呈各种配位数时的氧化态指定,而文献报道的B=0.055nm和R0=0.1859nm主要对于低配位的情况能取得Sn(Ⅱ)原子价态指定的较好结果.本研究证明,进一步研究键价参数对键价和(BVS)计算至关重要的那些可能的因素实乃当务之急.  相似文献   

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