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111.
112.
The Molecule S?GeCl2. Matrix IR Investigation and Ab initio SCF Calculation Molecular S?GeCl2 is found in a matrix reaction between the high-temperature molecule Ge?S and Cl2. A structure analog to that of phosgene can be derived from the isotopical shifts (70Ge/72Ge/73Ge/74Ge/76Ge and 35Cl/37Cl) within the IR spectra. The normal coordinate analysis results for the Ge?S force constant a value of 4.21 mdyn/Å. The spectroscopic results are confirmed by ab initio SCF calculations.  相似文献   
113.
We have synthesized a new series of azo‐bis antipyrine derivatives from a one‐pot multicomponent Knoevenagel/Michael addition reaction of antipyrine, with a diversity of azo aldehydes in ethanol and L‐Proline as a catalyst under reflux condition. The anti‐inflammatory activity of the final products was assessed using the inhibition of albumin denaturation technique. Compound 3f showed an inhibitory effect with IC50 values of 3.6 μM with respect to the standard anti‐inflammatory drug Aspirin, with IC50 values of 2 μM. In addition, molecular docking was performed to confirm the in vitro results against the enzymatic inhibition activity of COX‐2 enzymes in which compound 3f showed good binding affinity with an inhibition constant (Ki) of 1.79 nM.  相似文献   
114.
Mono‐ ( 3a – 3e and 4a – 4e ) and bis‐ferrocene ( 5a – 5e and 6a – 6e ) conjugated 5‐substituted uracil derivatives that are bridged by 1,2,3‐triazole linker were synthesized. The impact of ferrocene unit and spacer between ferrocene and triazole on radical scavenging potency was observed. Bis‐ferrocenyl uracil derivatives exhibited better antiproliferative activities than their mono‐ferrocenyl analogs. Bis‐ferrocenyl methyl‐ ( 5b ) and halogen‐substituted ( 5e , 6c , and 6d ) uracil derivatives showed pronounced and selective cytostatic activities on colon adenocarcinoma (CaCo‐2) and Burkitt lymphoma (Raji) cells, with higher potency and selectivity than the reference drug 5‐fluorouracil. Generation of reactive oxygen species (ROS) in CaCo‐2 and Raji cells when treated with compounds 5b , 5e , and 6d was observed. Bis‐ferrocenyl 5‐chlorouracil 6c induced significant disruption in mitochondrial membrane potential that is accompanied by activation of apoptosis in CaCo‐2, Raji, and acute lymphoblastic leukemia (CCRF‐CEM) cells, while 6d caused mitochondrial dysfunction and apoptosis induction in CaCo‐2 and Raji cells. Potent antiproliferative activity of 6c and 6d could be associated with mitochondrial membrane potential disruption accompanied by apoptosis induction. Our findings highlighted 6c and 6d with potent and selective antiproliferative activity on CaCo‐2, Raji, and CCRF‐CEM cells that may be associated with targeting cancer cell mitochondria, as a molecular target.  相似文献   
115.
利用水热法合成了2种新的双咪唑及二元羧酸配体镉配合物[Cd(sdc)(bipe)]·H_2O(1)和[Cd(bpdc)(bipe)(H_2O)](2)[bipe=bis(4-imidazolphenoxy)ethane,H_2sdc=4,4’-sulfonyldibenzoic acid,H_2bpdc=biphenyl-4,4’-dicarboxylic acid].通过元素分析、红外光谱(IR)、X射线单晶衍射和热重分析(TG)等方法对其进行表征,并测试了2种化合物的荧光性质.化合物1展示了一个具有{4~4·6~2}拓扑的(4,4)-连接的sql二维空间网络结构,配体与金属间荷移跃迁化合物2显示了一个具有(4~(12)·6~3)的六连接pcu网状拓扑结构.荧光测试结果显示,配体与金属间发生的荷移跃迁使得化合物1和2的荧光发射峰与配体bipe相比明显发生了红移.  相似文献   
116.
胡佳  高璐  宋振雷 《合成化学》2017,25(4):277-281
C3-位偕双硅取代的2,3-环氧醇分别与对甲苯磺酰氯、溴素和单质碘发生C3-位区域及立体选择性环氧开环/卤代反应合成了15个新的C3-位卤代偕双硅基1,2-二醇类产物,收率64%~87%,其结构经1H NMR, 13C NMR和HR-MS(ESI)表征。产物的立体结构经3-[二甲基(苯基)甲硅烷基]-3-碘-3-(三甲基甲硅烷基)丁烷-1,2-二醇(8d)的X-射线单晶衍射确证。  相似文献   
117.
The CdII three‐dimensional coordination poly[[[μ4‐1,4‐bis(1,2,4‐triazol‐1‐yl)but‐2‐ene]bis(μ3‐5‐carboxybenzene‐1,3‐dicarboxylato)dicadmium(II)] dihydrate], {[Cd2(C9H4O6)2(C8H10N6)]·2H2O}n , (I), has been synthesized by the hydrothermal reaction of Cd(NO3)2·4H2O, benzene‐1,3,5‐tricarboxylic acid (1,3,5‐H3BTC) and 1,4‐bis(1,2,4‐triazol‐1‐yl)but‐2‐ene (1,4‐btbe). The IR spectrum suggests the presence of protonated carboxylic acid, deprotonated carboxylate and triazolyl groups. The purity of the bulk sample was confirmed by elemental analysis and X‐ray powder diffraction. Single‐crystal X‐ray diffraction analysis reveals that the CdII ions adopt a five‐coordinated distorted trigonal–bipyramidal geometry, coordinated by three O atoms from three different 1,3,5‐HBTC2− ligands and two N atoms from two different 1,4‐btbe ligands; the latter are situated on centres of inversion. The CdII centres are bridged by 1,3,5‐HBTC2− and 1,4‐btbe ligands into an overall three‐dimensional framework. When the CdII centres and the tetradentate 1,4‐btbe ligands are regarded as nodes, the three‐dimensional topology can be simplified as a binodal 4,6‐connected network. Thermogravimetric analysis confirms the presence of lattice water in (I). Photoluminescence studies imply that the emission of (I) may be ascribed to intraligand fluorescence.  相似文献   
118.
A new 2,7‐bis(diphenylamino)naphthalene‐based diamine monomer, N,N′bis(4‐aminophenyl)‐N,N′bis(4‐methoxyphenyl)‐2,7‐naphthalenediamine, was synthesized and polymerized with various aromatic dicarboxylic acids via the phosphorylation polyamidation reaction leading to a new series of redox‐active and electrochromic aromatic polyamides. The polyamides exhibited high solubility in many polar aprotic solvents, good film‐forming ability, and high thermal stability. They also showed stable electrochemical stability and anodically green coloring when oxidized. The two arylamino centers showed a weak electronic interaction via the 2,7‐naphthalenediyl bridge, and thus they started to oxidize almost at the same time. No intervalence charge transfer (IVCT) absorption was observed during the oxidation processes of these polyamides. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 1409–1421  相似文献   
119.
In this paper, the synthesis and characterization of a series of latent polymeric bis(N‐heterocyclic carbene) (NHC) copper(I) complexes is reported, which can be activated for the copper(I)‐catalyzed azide/alkyne cycloaddition (CuAAC) via ultrasound. To prove the influence of chain length and nature of the polymer towards the activation, poly(isobutylene) (PIB), poly(styrene) (PS) and poly(tetrahydrofuran) (PTHF) are synthesized via living polymerization techniques (LCCP, ATRP, CROP) obtaining different chain lengths (from 2500 to 9000 g/mol), followed by quaternization with N‐methylimidazole, generating the corresponding N‐methylimidazolium‐telechelic polymers. The deprotonation of these macroligands via strong bases like sodium tert‐butoxide (NaOtBu) or potassium hexamethyldisilazide (KHMDS) yields the free N‐heterocyclic carbenes (NHCs), which are used to coordinate to tetrakis(acetonitrile)copper(I) hexafluorophosphate, forming the final polymer‐based mono‐ and bis(N‐methylimidazole‐2‐ylidene) copper(I)X complexes. The structural proof of these complexes is accomplished via 1H‐NMR spectroscopy, MALDI‐TOF‐MS and GPC‐techniques. The activation of the copper(I) biscarbene catalysts by ultrasound is studied by GPC, revealing the cleavage of one shielding NHC‐ligand. The initial catalytic latency and the via ultrasound introduced catalytic activation is successfully demonstrated monitoring a CuAAC “click” reaction of benzyl azide and phenylacetylene by in situ 1H‐NMR spectroscopy introducing thus “click” conversions up to 97%. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 3893–3907  相似文献   
120.
{Fe3O4@SiO2@(CH2)3‐thiourea dioxide‐SO3H/HCl}, a newly reported nanomagnetic core–shell supported solid acid catalyst, was successfully employed in the preparation of 4,4′‐(arylmethylene)bis(1H –pyrazol‐5‐ol) and pyrano[3,2‐c ]pyrazole derivatives. The presented methods are very efficient and high‐yielding. Also, the catalyst exhibited powerful potential for reusability in both types of reactions.  相似文献   
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