三甲氧基苄啶分子印迹整体柱的制备及色谱性能

选择甲基丙烯酸为功能单体\, 甲基丙烯酸乙二醇双酯为交联剂, 制备了三甲氧基苄啶分子印迹整体柱, 对整体柱材料的形貌进行了表征, 并且研究了TMP和5种磺胺类药物在分子印迹整体柱上的色谱行为.     

5，10，15，20-四 [4-(4''-乙基哌嗪基)苯基]卟啉的合成及其与DNA的相互作用

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。     

Studies on Thermodynamics Features of the Interaction between Imidacloprid and Bovine Serum Albumin

At different temperatures, the interactions between imidacloprid （IMI） and bovine serum albumin （BSA） were investigated with a fluorescence quenching spectrum, a synchronous fluorescence spectrum, a three-dimensional fluorescence spectrum and an ultraviolet-visible spectrum. The average values of bonding constants （KLB： 3.424 × 10^4 L,mol^-1）, thermodynamic parameters （△H： 5.188 kJ,mol^-1, △G^（○—）：-26.36 kJ,mol^-1, △S： 103.9 J,K^-1,mol^-1） and the numbers of bonding sites （n： 1.156） could be obtained through Stern-Volmer, Lineweaver-Burk and ther- modynamic equations. It was shown that the fluorescence of BSA could be quenched for its reactions with IMI to form a certain kind of new compound. The quenching belonged to a static fluorescence quenching, with a non-radiation energy transfer happening within a single molecule. The thermodynamic parameters agree with △H〉 0, △S〉0 and△G^（○-）〈0, suggesting that the binding power between IMI and BSA should be mainly a hydrophobic interaction.     

Synthesis,structures and properties of two novel copper(II) complexes with hydrogen bonding supramolecular networks

Two novel complexes, [Cu(HL)₂(H₂O)]₂(OH)₂(ClO₄)₂·1.5H₂O (1) and [Cu(HL)₂]Cl₂·4H₂O (2), have been prepared by reacting copper salts with the 4-amino-3-ethyl-1,2,4-triazole-5-thione (HL) ligand in neutral solution and in HCl (6 mol L^–1) medium, respectively. They were characterized by FT-IR and u.v.–vis. spectra, and the structures were determined by single crystal X-ray diffraction techniques. In both complexes, the triazole ligand chelated the metal ions through the amine and thione substituents on the five-membered ring. Complex (1) has a square-pyramidal copper(II) ion coordinated by two triazole ligands and one water molecule. Unlike (1), the Cu²⁺ ion in (2) displays its characteristic Jahn–Teller distortion with the distance of the Cl^– anions to metal ion further away than that of the triazole ligands. The most intriguing structural features of the title complexes are that the HL ligands chelate copper(II) ions through the N(1) and S(1) atoms, in a cis mode in (1) and a trans mode in (2). In both cases, self-assembled crystals, by supramolecular contacts simultaneously, form two multi-dimensional frameworks.     

Human immunoglobulin adsorption investigated by means of quartz crystal microbalance dissipation, atomic force microscopy, surface acoustic wave, and surface plasmon resonance techniques

Time-resolved adsorption behavior of a human immunoglobin G (hIgG) protein on a hydrophobized gold surface is investigated using multitechniques: quartz crystal microbalance/dissipation (QCM-D) technique; combined surface plasmon resonance (SPR) and Love mode surface acoustic wave (SAW) technique; combined QCM-D and atomic force microscopy (AFM) technique. The adsorbed hIgG forms interfacial structures varying in organization from a submonolayer to a multilayer. An "end-on" IgG orientation in the monolayer film, associated with the surface coverage results, does not corroborate with the effective protein thickness determined from SPR/SAW measurements. This inconsistence is interpreted by a deformation effect induced by conformation change. This conformation change is confirmed by QCM-D measurement. Combined SPR/SAW measurements suggest that the adsorbed protein barely contains water after extended contact with the hydrophobic surface. This limited interfacial hydration also contributed to a continuous conformation change in the adsorbed protein layer. The viscoelastic variation associated with interfacial conformation changes induces about 1.5 times overestimation of the mass uptake in the QCM-D measurements. The merit of combined multitechnique measurements is demonstrated.     

Design, synthesis, and photophysical studies of a porphyrin-fullerene dyad with parachute topology; charge recombination in the marcus inverted region

As part of a continuing investigation of the topological control of intramolecular electron transfer (ET) in donor-acceptor systems, a symmetrical parachute-shaped octaethylporphyrin-fullerene dyad has been synthesized. A symmetrical strap, attached to ortho positions of phenyl groups at opposing meso positions of the porphyrin, was linked to [60]-fullerene in the final step of the synthesis. The dyad structures were confirmed by (1)H, (13)C, and (3)He NMR, and MALDI-TOF mass spectra. The free-base and Zn-containing dyads were subjected to extensive spectroscopic, electrochemical and photophysical studies. UV-vis spectra of the dyads are superimposable on the sum of the spectra of appropriate model systems, indicating that there is no significant ground-state electronic interaction between the component chromophores. Molecular modeling studies reveal that the lowest energy conformation of the dyad is not the C(2)(v)() symmetrical structure, but rather one in which the porphyrin moves over to the side of the fullerene sphere, bringing the two pi-systems into close proximity, which enhances van der Waals attractive forces. To account for the NMR data, it is proposed that the dyad is conformationally mobile at room temperature, with the porphyrin swinging back and forth from one side of the fullerene to the other. The extensive fluorescence quenching in both the free base and Zn dyads is associated with an extremely rapid photoinduced electron-transfer process, k(ET) approximately 10(11) s(-)(1), generating porphyrin radical cations and C(60) radical anions, detected by transient absorption spectroscopy. Back electron transfer (BET) is slower than charge separation by up to 2 orders of magnitude in these systems. The BET rate is slower in nonpolar than in polar solvents, indicating that BET occurs in the Marcus inverted region, where the rate decreases as the thermodynamic driving force for BET increases. Transient absorption and singlet molecular oxygen sensitization data show that fullerene triplets are formed only with the free base dyad in toluene, where triplet formation from the charge-separated state is competitive with decay to the ground state. The photophysical properties of the P-C(60) dyads with parachute topology are very similar to those of structurally related rigid pi-stacked P-C(60) dyads, with the exception that there is no detectable charge-transfer absorption in the parachute systems, attributed to their conformational flexibility. It is concluded that charge separation in these hybrid systems occurs through space in unsymmetrical conformations, where the center-to-center distance between the component pi-systems is minimized. Analysis of the BET data using Marcus theory gives reorganization energies for these systems between 0.6 and 0.8 eV and electronic coupling matrix elements between 4.8 and 5.6 cm(-)(1).     

Thermal Reaction of Azulene and Some of Its Symmetrically Substituted Methyl Derivatives with Dimethyl Acetylenedicarboxylate

It is shown that azulene ( 1 ) and dimethyl acetylenedicarboxylate (ADM) in a fourfold molar excess react at 200° in decalin to yield, beside the known heptalene- ( 5 ) and azulene-1,2-dicarboxylates ( 6 ), in an amount of 1.6% tetramethyl (1RS,2RS,5SR,8RS)-tetracyclo[6.2.2.2^2,50^1,5]tetradeca-3,6,9,11,13-pentaene-3,4,9,10-tetracarboxylate(‘anti’-7) as a result of a SHOMO (azulene)/LUMO(ADM)-controlled addition of ADM to the seven-membered ring of 1 followed by a Diels-Alder reaction of the so formed tricyclic intermediate 16 (cf. Scheme 3) with a second molecule of ADM. The structure of ‘anti’-7 was confirmed by an X-ray diffraction analysis. Similarly, the thermal reaction of 5,7-dimehtylazulene ( 3 ) with excess ADM in decalin at 120° led to the formation of ca. 1% of ‘anti’- 12 , the 7,12-dimethyl derivative of‘anti’-7, beside of the corresponding heptalene- 10 and azulene-1,2-dicaboxylated (cf Scheme 2). The introduction of Me groups at C(1)and C(3)of azulene ( 1 ) and its 5,7-dimethyl derivative 3 strongly enhance the thermal formation of the corresponding tetracyclic compound. Thus, 1,3-dimethylazulene ( 2 ) in the presence of a sevenfold molar excess of ADM at 200° yielded 20% of ‘anti’- 9 beside an equal amount of dimethyl 3-mehtylazulene-1,2-dicarboxylate ( 8 ;cf. Scheme 1), and 1,3,5,7-tetramethylazulene ( 4 ) with a fourfold molar excess of ADM AT 200° gave a yield of 37% of‘anti’- 15 beside small amount of the corresponding heptalene- 13 and azulene-1,2-dicarboxylates 14 (cf.Scheme 2).     

Determination of unbound cefamandole in rat blood by microdialysis and microbore liquid chromatography

To analyze unbound cefamandole in rat blood, a method combing microdialysis with microbore liquid chromatography has been developed. A microdialysis probe was inserted into the jugular vein/right atrium of male Sprague-Dawley rats to examine the unbound cefamandole level in the rat blood following cefamandole administration (50 mg/kg, i.v.). The dialysates were directly submitted to a liquid chromatographic system. Samples were eluted with a mobile phase containing acetonitrile-methanol-100 mM monosodium phosphate (pH 5.0; 15:20:65, v/v). The UV wavelength was set at 270 nm for monitoring the analyte. Using the retrograde method, at infusion concentrations of 1 microg/mL of cefamandole, the in vivo microdialysis recoveries were 55.44% for the rat blood (n = 6). Intra- and inter-assay accuracy and precision of the analyses were < or = 10% in the range of 0.1-10 microg/mL. Pharmacokinetic parameters were calculated from the recovery-corrected dialysate concentrations of cefamandole vs time data. The elimination half-life (t1/2,beta) was 21.6 +/- 1.6 min. The results suggest that the pharmacokinetics of unbound cefamandole in blood following cefamandole administration (50 mg/kg, i.v., n = 5) fit best to the two-compartmental model.     

Dehydrogenation activity and structure of polyaniline supported heteropolyacid catalysts

Polyaniline(PAN) supported H₆P₂W₁₈O₆₂(PW) , H₃PMo₁₂O₄₀ (PMo) and H₄PMo₁₁VO₄₀(PMoV) catalysts were prepared and their activities for hexanol conversion were tested. IR, XRD, ICP and SEM measurements proved that the heteropolyacids (HPA) could be supported on this type of polymer. The PAN supported HPA catalysts exhibit higher redox activities and low acid-base activities for the hexanol conversion. The redox activities increase with increasing amount of the heteropolyacid. Substitution of Mo ion by V ion results in an increase of redox activities of the catalysts. This revised version was published online in June 2006 with corrections to the Cover Date.     

Production of 1,3-propanediol by Klebsiella pneumoniae

1,3-Propanediol (1,3-PD) has numerous applications from polymers to cosmetics, foods, lubricants, and medicines. Recently, there are strong industrial interests in a new kind of polyester, polytrimethylene terephthalate, with 1,3-PD as a monomer. This new polyester shows significant promise for use in carpeting and textiles. In this article we introduce a mild aerobic fermentation process using a strain screened from Klebsiella pneumoniae ATCC 25955, which is insensitive to oxygen, to produce 1,3-PD. We also describe a two-step fermentation process starting with glucose that was converted into glycerol with a glycerol-producing yeast, followed by K. pneumoniae that converts glycerol into 1,3-PD without intermediate isolation and purification of glycerol.