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1.
Eight new compounds of α- and β- M2H4[SiW16Cr2(OH2)2O ] .xH2O types, where M = K, Me4N, Et4N or n-Bu4N, and 0+6=6,were synthesized from trivacant heteropoly tungstate α-and β-[SiW9O34]10 precursors, and characterized by elemental analysis, thermal gravimetric analysis, IR, UV-visible spectra, X-ray photoelectron spectroscopy(XPS), polarography, magnetic measurements and X-ray powder diffraction. The IR and UV spectra conJEirm that α-and β-[SlW10Cr2(OH2)2O24]6- isomers possess α-and β-Keg-gin structures. The differences between α-and β-isomers in IR, UV spectra and polarography are discussed.  相似文献   

2.
八乙酰乳糖与一缩二乙二醇或二缩三乙二醇在 BF3.Et2 O催化下反应生成相应的 β-糖苷 ,后者在同样的催化剂存在下再与八乙酰乳糖反应生成对称的 β-构型二聚体 .糖苷与二聚体在甲醇钠 /甲醇溶液中脱去乙酰基生成目标化合物用于抗癌转移活性研究 .  相似文献   

3.
(+)-樟脑与6-甲基-2-氨甲基吡啶缩合得到一种新的手性双齿配体-1,7,7-三甲基-双环[2.2.1]-2-(6'-甲基-2'-氨甲基)吡啶亚胺(1), 与二价钯生成配合物2, 晶体属P21空间群, 晶胞参数为a=10.641(2), b=10.706(2), c=11.011(2)埃; β=115.63(1)°;V=1131.15(40)埃^3; Z=2, 二价钴与1生成配合物3, 晶体属PI空间群, 晶胞参数为a=7.429(2), b=7.971(3), c=16.304(5)埃; a=80.19(3), β=77.10(2), γ=83.21(2)°; V=924.25(56)埃^3; Z=2。根据晶体数据讨论了分子的结构特征, 并对配合物的红外、紫外和核磁共振谱的变化作了解释。  相似文献   

4.
(+)-樟脑与6-甲基-2-氨甲基吡啶缩合得到一种新的手性双齿配体-1,7,7-三甲基-双环[2.2.1]-2-(6'-甲基-2'-氨甲基)吡啶亚胺(1), 与二价钯生成配合物2, 晶体属P21空间群, 晶胞参数为a=10.641(2), b=10.706(2), c=11.011(2)埃; β=115.63(1)°;V=1131.15(40)埃^3; Z=2, 二价钴与1生成配合物3, 晶体属PI空间群, 晶胞参数为a=7.429(2), b=7.971(3), c=16.304(5)埃; a=80.19(3), β=77.10(2), γ=83.21(2)°; V=924.25(56)埃^3; Z=2。根据晶体数据讨论了分子的结构特征, 并对配合物的红外、紫外和核磁共振谱的变化作了解释。  相似文献   

5.
通过配基置换反应合成出两个新的三核钼簇合物[Mo3S4(DTC)4(DMF)](EtOH)(1)和[Mo3S4-(DTC)4(Py)](Py)2(H2O)(2). 用X射线衍射法测定了这两个簇合物的晶体结构.簇合物1的空间群为PT, 晶胞参数: A=10.624(5), b=11.373(2), c=19.216(5)埃;α=87.92(2), β=79.89(3), γ=69.44(3)°; Z=2. 簇合物2的空间群为PT, 晶胞参数:a=11.505(2), b=11.945(1), c=18.974(2)埃; α=99.18(1), β=94.82(1), γ=93.84(1)°; Z=2, 结构分析结果表明, 两个簇合物的簇胳均是{Mo3S4}^4^+的三核钼原子簇, 对簇合物中配基对Mo-Mo键的影响以及配基置换反应的规律性进行了讨论.  相似文献   

6.
Four 2- (α-hydroxyalkyl ) -2-oxazolines and a 2- (α-hydroxy-α,α-diphenyl) -2-benzooxazole were synthesized from β-amimoalcohols and α-hydroxy carboxylic acids under microwave irradiation in the absence of a solvent.  相似文献   

7.
Two new triterpenoid sapon.ins 1 and 2 were isolated from the crude saponin extract of Oxytropis glabra DC by Si gel chromato-grapny . Saponins 1 and 2 were determined to be 3-0-1 β-D-glucopyranosy 1 (1-2)- β -D-glucuronopyranosyl azukisapogenol methyl ester and 3-O-[β-D-glucopyranosyl(1 - 2 ) - β -D-glucuronopyranosyl] azukisapogenol amide, respectively by spectral analysis and chemical methods.  相似文献   

8.
合成了三氨基胍三硝基间苯二酚盐(TAGH)2(TNR) (TAG: 三氨基胍; TNR: 2,4,6-三硝基间苯二酚), 并对其进行了元素分析及红外光谱表征. 利用X射线单晶衍射分析测定了其晶体结构. 该晶体属于单斜晶系, 空间群为C2/c, 晶体学数据为, a=2.2892(6) nm, b=1.2802(3) nm, c=1.3661(4) nm, β=111.174(5)°, V=3.7333(16) nm3, Z=8. 该化合物是由二个C(N2H3)+3与一个(C6HN3O8)2-相结合而成的离子型化合物. 用差示扫描量热法、热重法和微商热重法研究了该化合物的热分解过程, 研究结果表明, 在10 K·min-1的升温速率下, 该化合物只有一个剧烈的放热分解过程, 该过程发生在450.1-477.7 K之间, 且分解产物主要是气体产物.  相似文献   

9.
HPMTFP与1,10—菲罗啉(Phen)等中性萃取剂对Co(Ⅱ)的协同萃取   总被引:3,自引:0,他引:3  
本文研究了以1-苯基-3-甲基-4-4-三氟乙酰基吡唑啉酮-5(HPMTFP)与1,10菲罗啉(Phen)。三辛基氧磷(TOPO)、三苯基氧磷(Ph_3PO)、三丁基磷酸酯(TBP)和二戊基亚砜(DASO)的氯仿溶液对CO(Ⅱ)的协同萃取.协萃图上发现,HPMTFP与Phen协萃效应显著,与TOPO、Ph_3PO协萃效应较小,而与TBP、DASO基本上无协萃效应.本文由协萃图数据斜率分析和求协萃反应平衡常数的方法,推断萃合物组成为Co(PMTFP)_2·B(B分别为Phen、TOPO、Ph_3PO),求得的各协萃反应的平衡常数如下:Co~(2+)+2HPMTFP_(0)+Phen_(0) Co(PMTFP)_2·Phen_(0)+2H~+ β_(12)=9.57Co~(2+)+2HPMTFP_(0)+TOPO_(0) Co(PMTFP)_2·TOPO_(0)+2H~+ β_(12)=9.56×10~(-3)Co~(2+)+2HPMTFP_(0)+PH_3PO_(0) Co(PMTFP)_2·PH_3PO_(0)+2H~+ β_(12)=5.01×10~(-3)根据模拟萃合物Co(PMTFP)_2·2C_2H_5OH和萃合物Co(PMTFP)_2·Phen的单晶X-射线结构研究结果,讨论了萃合物的结构和产生协萃效应的原因。  相似文献   

10.
Two new compounds of A- type α-and β-K4.5H2.5[SiW9Cr3(OH2)3O37]·xH2O were synthesized. The two kinds of isomers of α-and β-SiW12-xCrx(x=2, 3) were identified by Second-derivative IR spectroscopy and cyclic voltammetry. The numbers of electrons involved in reductions were obtained by controlled potential electrolyses of the isomers.  相似文献   

11.
The crystal structure of N-(t-butoxycarbonyl)-L-methionyl-glycine ethyl ester has been determined. The crystal data are: P2_1, α=14.504(6), b=5.015(2), c=12.762(6), β=93.63(3)°, Z=2. The final R is 0.066 for 1495 reflections. The torsion angles of methionyl side chain are X~1=-177.7°. X~2=178.6°, X~3=-71.7°. The plan of the side chain is approximately vertical to the plan of the peptide. The peptide main chains are packed in a parallel β-sheet structure, the main chain torsion angles(φ,ψ) of the methionyl residue being (-118.9°,115.4°). This compound, BOC-L-Met-Gly-OEt, is very similar to certain derivatives used in the peptide transport studies which were carried out by Naider et al.  相似文献   

12.
In the process of preparing α-diazo carbonyl compound 2 by imidation of 1, we unexpectedly observed a direct conversion of the hydroxyl group into trichloroacetylamino group. In this presentation, we report this unprecedented reaction, as well as the Rh2(OAc)4-catalyzed reaction of the resulting β-(trichloroacetyl)amino β-diazo carbonylcompounds 3. [ 1]  相似文献   

13.
合成了三(对氟苄基)氯化锡(1)和三(对氟苄基)锡N,N-(1,4-亚丁基)氨荒酸酯(2).通过元素分析、红外光谱和核磁共振氢谱对其结构进行了表征.用X射线单晶衍射测定了这两个化合物的晶体结构.化合物1为单斜晶系,空间群P21, a=0.8403(3) nm, b=0.5958(2) nm, c=2.0016(8) nm, β=97.052(6)°, Z=2, V=0.9945(7) nm3, Dc=1.608 g/cm3, μ=1.447 mm-1, R1=0.0397, wR2=0.0813.化合物2为单斜晶系,空间群P21/n, a=0.8786(9) nm, b=1.993(2) nm, c=1.5039(15) nm, β=103.548(15)°, Z=4, V=2.560(4) nm3, Dc=1.537 g/cm3, μ=1.197 mm-1, R1=0.0363, wR2=0.0796. 在1的晶体中,锡原子呈四配位畸变四面体构型;2的晶体中,锡原子则是五配位畸变三角双锥构型.  相似文献   

14.
The copper( Ⅱ ) complex, [Cu(oxpn)Cu(tmen)2](ClO4)2 was synthesized, where oxpn is N, N' -bis ( 3-aminopropyl) oxamido and tmen is N, N, N' N' -tetram-ethylethylenediamine. The crystal is triclinic, space group P 1, a=1-2349(2), b = 1.3093(2), c=1. 3855(2) nm, α=61-88(1), β=69.49(1), γ=57.91(1)°? V = 1. 6589 nm3, Z = 2. Both copper( Ⅱ ) ions are in a square pyramidal coordination environment , and linked by oxamido bridge. The distance between them is 0. 526 nm. Variable temperature (4. 2-300 K) magnetic susceptibility data for this complex show that there exists a relatively large antiferromagnetic exchange interaction between the two copper( Ⅱ ) ions with a J value of-740. 40 cm-1.  相似文献   

15.
1 INTRODUCTION In recent years, chiral β-amino alcohols have attracted much attention due to their special bio- logical functions and catalytic activities. Chiral β- amino alcohol moieties are usually found not only in natural products (e.g., cinchona alkaloids, ephe- drine, toxal, etc.) with special biological activities[1, 2], but also critical structural segments of some syn- thesized biologically active compounds, such as adrenergic agonists or antagolist[3, 4] and inhibitors for HI…  相似文献   

16.
合成了17个新的三(2-甲基-2-苯基丙基)锡氧衍生物.利用IR,1H NMR及元素分析确定了化合物的组成,描述了化合物7的结构.部分化合物的生物活性测试结果表明,它们具有很好的杀螨效果,且阴离子配体对生物活性有一定影响.  相似文献   

17.
β—环糊精衍生物的金属配合物催化RNA的水解   总被引:5,自引:0,他引:5  
用 β-环糊精 (β- CD)与马来酸酐合成了双 (6 -氧 -丁烯二酸单脂 ) - β- CD(简称 E1 ) ,用 KI对 E1 进行取代 ,生成了双 (6 -碘 ) - β- CD,其与组氨酸在 Na OH溶液中反应 ,生成双 (6 -氮 -组胺酸 ) - β- CD(简称 E2 ) ,E2 分别与 Mg( )、Zn( )、Fe( )和 Fe( )形成配合物 .研究了这 4种金属配合物对 RNA的水解 ,并与 Na OH水解 RNA进行了比较 ,发现 E2 · Fe( )对 RNA的水解能力可达到 Na OH水解 RNA能力的 96 .9% .  相似文献   

18.
The adsorption of nitric oxide adsorption on clean Mod(111), Mo(111)/O2-(4×4), Mo(111)/O2-(1×3), Mo(111)/O2-(112) facets and Mo(111) oxide surfaces was studied. Mass 28 (N2) desorption spectra show two high temperature peaks at approximate 1030 (β1) and 1200K (β2). For NO exposures less than 0. 1 L only the ft peak was observed. At higher exposures, the ft peak appeared and small amounts of N2O as well as NO desorbed. The preadsorption of oxygen blocked the β2 desorption partially on the (4×4) and (1×3) surfaces and fully on the (112) facet and oxide surfaces. In addition, the β1 desorption peak shifted to higher temperatures with increasing oxygen preexposure.  相似文献   

19.
<正> [C12H28O4N2](NO3)2, Mr = 388. 45, monoclinic space group P21/ n,a = 7. 811(2), b = 10.626(4), c= 11. 823(6) A , β=106.51(3)°, Z = 2, Dc = 1.37 gem-3, V = 940. 8(7) (?)3 F(000) = 416, μ(MoKα) =1. 3 cm-1, R =0. 044 for 1373 reflections. The structure contains prdtonated azacrown [H2(2,2)]2+ and two (NO3-) which are bridged by four hydrogen bonds O(nitrate) ...H-N(crown). The ion [H2(2,2)]2+ in the title crystal lies on the crystallographic center of symmetry. There is half a [H2(2,2)]2+ and one NO3- in an asymmetric unit.  相似文献   

20.
合成了侧链携带金刚烷的温敏性聚合物(Pnipam-Ad)及环糊精二聚体(trans-Azo β-CD Dimer),利用Pnipam-Ad侧链的金刚烷与trans-Azo β-CD Dimer的主客体识别作用构筑了超分子体系.以二维核磁共振谱(2D NMR)、粘度法等手段对Pnipam-Ad与trans-Azo β-CD Dimer之间的主客体包结作用进行了研究,两者之间的缔合受Pnipam-Ad和trans-Azo β-CD Dimer浓度及trans-Azo β-CD Dimer光异构的影响.此外,trans-Azo β-CD Dimer对Pnipam-Ad聚合物链的物理交联作用使两者混合溶液的最低临界溶解温度(LCST)低于纯P(NIPAM)的LCST.  相似文献   

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