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1.
A string of four new hetero binuclear Ru(III) complexes of ferrocenecarboxaldehyde-4(N)-substituted thiosemicarbazones were synthesized and characterized by various spectral (infrared, ultraviolet–visible, Electron Paramagnetic Resonance (EPR) and High Resolution Mass Spectrometry (HR-MS) techniques. The binding abilities of the ligands/complexes with nucleic acid (calf thymus DNA, CT-DNA) and bovine serum albumin (BSA) were analyzed by absorption and emission titration methods. The complexes exhibited better DNA binding affinity than their parent ligands. The interaction with CT-DNA was found to be intercalative and with BSA static quenching mechanism was observed. All the synthesized Ru(III) complexes were subjected to study their in vitro cytotoxicity against MCF-7 (human breast cancer) and HT-29 (human colon cancer) cell lines. Among the four complexes, complex 3 [RuCp (FF-etsc)PPh3]Cl exhibited the highest cytotoxicity in MCF-7 cells and complex 4 [RuCp (FF-ptsc)PPh3]Cl was the most active on HT-29 cells.  相似文献   
2.
The γcmc values of CTAB-SDS decrease from 63.67 mN/m at 10‡C to 36.38 mN/m at 90‡C, slightly lower than those of either CTAB or SDS. Correspondingly, the CMC of CTAB-SDS decreases almost by half. The increase of surface activity of CTAB-SDS can be attributed to the relatively weak electrostatic interaction at high temperature, which is supported by the increase of solubility of CTAB-SDS with rise in temperature. Catalytic effect on oxidation of toluene derivatives with potassium permanganate follows the order CTAB-SDS > SDS > CTAB. This is not caused by the dissociative effect of CTAB-SDS with low surface activity at low temperature, as seen from the fact that almost all oxidative products can be retrieved for different toluene derivatives and surfactants by mimicking the conditions of reaction. In the emulsifications of toluene derivatives at 90‡C, the time that turbid water layers of surfactant solutions take to become clear is the same as that of the catalytic effect on oxidation of toluene derivatives. Thus, it can be inferred that surfactants can improve the oxidation yields of toluene derivatives by increasing the contact between two reacting phases.  相似文献   
3.
Summary A system for capillary electrophoresis combined with enzymatic assay has been evaluated for the two enzymes glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase. Instrumentation included a post-column reactor coupled to the separation capillary by a liquid junction. A technique for generating a substrate solution flow into the reactor by utilizing two high voltage supplies is proposed. This method offers a high degree of freedom in optimizing the separation and enzymatic reaction conditions individually. Possibilities for improving the enzymatic assay sensitivity were also examined.  相似文献   
4.
Copper bromide was used as a catalyst for the addition of pyrroles to enones. When both the reactants were used in equimolar amounts, mono and dialkylated products were obtained. However, the use of excess enone furnished only dialkylated products. Thus, copper bromide was shown to be an efficient catalyst for the dialkylation of pyrroles.  相似文献   
5.
A cluster complex of the composition [Th(DMSO)8Cl][Re6Se7Cl7] has been obtained by interaction of ThCl4 solution in DMSO with a water solution of K3[Re6Se7Cl7] and KCl. The compound crystallizes in the rhombic space group Pbcm with unit cell parameters a = 12.262(2) Å, b = 19.653(6) Å, c = 23.603(6) Å, V = 5688(2) Å3, Z = 4, d calc = 3.282 g/cm3. The structure is built from centrosymmetric cluster anions [Re6Se7Cl7]3? and complex cations [Th(DMSO)8Cl]3+ possessing mirror-plane symmetry, half of the DMSO ligands being doubly disordered.  相似文献   
6.
利用离子速度影象技术研究了正一溴丁烷(n-C4H9Br)在231~267 nm波段的光解,得出了如下结论:正一溴丁烷(n-C4H9Br)在231~267 nm波段的吸收源于基态到三个最低激发态的跃迁,这三个激发态标识为1A″、2A′和3A′;发生在这三个排斥态的势能面(PES)上的光解最终导致C4H9 Br(2P3/2)或C4H9 Br*(2P1/2)的产生;2A′和3A′态之间存在避免交叉(Avoided crossing)会影响最终的光解产物;从基态1A′到激发态1A″的跃迁矩垂直于对称面,也就垂直于C-Br键;从基态1A′到激发态3A′的跃迁矩平行于对称面,同时平行于C-Br键;从基态1A′到激发态2A′的跃迁矩在对称面内,且与C-Br键成53.1°夹角.我们也讨论了正一溴丁烷(n-C4H9Br)在234 nm和267 nm附近光解时的避免交叉几率(Avoided crossingprobability),以及它对单通道相对产额(Relative fraction of the individual pathways)的影响.  相似文献   
7.
采用MTT比色法对体外培养的肿瘤细胞进行细胞毒作用实验,验证槲寄生蛋白注射液体外抗肿瘤效果.并且鉴定这种检测方法的有效性。实验结果表明槲寄生蛋白注射液有一定的体外抗肿瘤效果;MTT比色法是一种可用的体外细胞毒作用检测法,为新药品的开发提供了实验依据。  相似文献   
8.
Various types of alcohols and phenols were rapidly protected by hexamethyldisilazane in good to excellent yields at room temperature in the presence of catalytic amount of magnesium bromide ethyl etherate under solvent-free conditions. Good to excellent chemoselectivity was demonstrated for competitive protection of primary hydroxyls in the presence of secondary and tertiary alcohols. Highly selective protection of phenols in the presence of aromatic amines was also demonstrated successfully.  相似文献   
9.
10.
Crosslinked hyaluronan gels are used in various applications where their stability is a prerequisite. The sensitivity of such gels to hyaluronidase can be determined as an index of stability by several approaches: chromatography, electrophoresis, and viscometry. We describe here a test based on the colorimetric determination of the N-acetyl-d-glucosamine released by hyaluronidase in standardized conditions. The sensitivities to bovine testicular hyaluronidase of 11 different gels used to fill skin wrinkles (Restylane; Perlane; Juvéderm 18, 24, 24HV, 30, and 30HV; Surgiderm 18, 24XP, 30, and 30XP) were compared.The method was reproducible, easy to perform, not time-consuming and allowed us to demonstrate that the sensitivity to testicular hyaluronidase was dependent on the degree of crosslinking of the gels and also on their monophasic/biphasic nature. Under our conditions, Surgiderm 30, 24XP and 30XP were the most resistant gels.We propose to retain the hyaluronidase test to predict the in situ stability of a crosslinked gel used to fill skin wrinkles.  相似文献   
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