Synthesis and Antibacterial Activities of 7 β-Heterocyclyl-3-(2-substituted 1,3,4-thiadiazol-5-thiometbyl)Cephalosporin

Cephalosporin derivatives are an interesting class of β-lactam antibiotics because of their power against a large number of both Gram-positive and Gram-negative organisms. Many efforts have been made to synthesize cephalosporin by varying the substituents. Further pharmacological research indicated the inhibitory activity, broad-spectrum biological activity and β-lactamase resistance determined by the side chain at 7β position of 7-ACA and the structure of substituted group at C₃ position. Actually, most of its applications in clinic are the derivatives linked with heterocyclic at C₃ and 7β position of cephalosporin skeleton. Literature^[1] also revealed that cephalosporin containing aminothiazoloxime at the 7β position of 7-ACA used as antibiotics with obvious applications. Moreover, some compounds bearing 1,2,3-triazole ring at the C₃ position of 7-ACA have been reported to possess better antibacterial activity. For these purpose, we synthesized new cephalosporin 3a-c and 5a-c by the reaction of 7-ACA with 2-arylamino-1,3,4-thiadiazol-5-thioles, and then reacted with 1 -aryl-5-methyl-1H-1,2,3-triazol-4-formyl chloride 2 or aminothiazoloxime active ester 4,respectively.     

皂荚素的表面活性及其二元体系的热力学研究

通过表面张力的测定研究了皂荚素(GS)的表面活性及其热力学性质随温度的变化.测定了皂荚素分别与十二烷基磺酸钠、十二烷基聚氧乙烯醚硫酸钠、全氟辛酸钠、十二烷基脂肪醇聚氧乙烯(9)醚、辛基酚聚氧乙烯(10)醚及十六烷基三甲基溴化铵等复配的表面张力-浓度对数关系(γ～lgc)曲线,并用二维晶格模型及正规溶液理论计算了含皂荚素的二元表面活性剂溶液表面吸附层的组成、分子相互作用参数及分子交换能.结果表明,皂荚素主要呈现非离子表面活性剂的性质,与阳离子表面活性剂复配呈微弱的离子性.复配后分子交换能均小于零,复配增效.增效顺序为GS/阳离子>GS/非离子>GS/阴离子(表面活性剂复配体系).     

离子液体@TiO_2纳米复合材料的制备及其光催化性能

利用—Si—O—共价键将离子液体嫁接在纳米TiO_2表面,制备离子液体@TiO_2纳米复合材料,并利用红外光谱、差热分析、元素分析等技术手段进行了分析。光催化性能研究表明,在紫外光照射60 min后,[C8tespim]Br@TiO_2([C8tespim]:N-3-(3-三乙氧基硅烷基丙基)-4,5-二氢咪唑)复合材料能够将甲基橙100%脱色,明显优于TiO_2P25的光催化降解性能。同时发现其光催化性能与阴离子类型有密切关系,活性顺序为[C8tespim]Br@TiO_2[C8tespim]PF6@TiO_2[C8tespim]Tf2N@TiO_2。     

The synthesis, structural features and thermal behaviour of thiophene-containing dithiocarboxylate complexes of zinc(II)

The complexes [Zn₂(S₂CTR)₄] (T = 2,5-disubstituted thiophene, R = C₄H₉ (1), C₆H₁₃ (2), C₈H₁₇ (3), C₁₂H₂₅ (4) and C₁₆H₃₃ (5)) have been synthesized and their structural features investigated. Compared to the analogous dithiobenzoate complexes, the crystal structure determination of 2 revealed that the thiophene induces a “step-rod” chain pattern instead of the linear, rodlike structure found for the corresponding dithiobenzoates. Complexes 1–5 did not display mesophases under thermal conditions, but an irregular melting pattern was observed for 3 and 4.     

新型双苯并环己酮芳亚胺镍(Ⅱ)催化降冰片烯与甲基丙烯酸丁酯共聚合

采用自制的新型双苯并环己酮芳亚胺镍催化剂双苯并环己酮-2,6-二甲基苯亚胺镍(Ⅱ)(Ni{C₁₀H₈(O)C[2,6-C₆H₃(CH₃)₂N]CH₃}₂, C1)和双苯并环己酮-2,6-二氯苯亚胺镍(Ⅱ)(Ni{C₁₀H₈(O)C[2,6-C₆H₃Cl₂N]CH₃}₂, C2)与三五氟苯硼[B(C₆F₅)₃]结合, 在一定的反应条件下可高效催化降冰片烯(NB)与甲基丙烯酸正丁酯(n-BMA)的乙烯基加成共聚合. 提出了催化聚合时存在的可能失活机理; 研究了不同单体投料比对催化活性、 产率及产物性能的影响. 根据Kelen-Tüdõs方法分别估算出2种单体在不同催化体系下的竞聚率, 即当催化体系为C1/B(C₆F₅)₃时, 竞聚率r_n-BMA=0.02, r_NB=16.28, r_NB·r_n-BMA=0.32; 当催化体系为C2/B(C₆F₅)₃时, r_n-BMA=0.01, r_NB=64.83, r_NB·r_n-BMA=0.65. 结果表明, 2种单体在2种体系催化下均为无规共聚合.     

新型双杂环修饰的酰胺硫醚衍生物的合成和生物活性

首次设计并合成了16个新型1,2,4-三唑与1,3,4-噻二唑双杂环修饰的酰胺硫醚衍生物,并对其进行了结构表征。分别评价了目标分子对蛋白酪氨酸磷酸酶1B(PTP1B)和细胞分裂周期25磷酸酶B(Cdc25B)抑制活性,结果发现:16个目标分子对PTP1B具有良好的抑制活性,其中8-C-d和8-D-c的抑制作用最佳,半抑制浓度(IC_(50)值)分别为(1.19±0.22)mg/L和(1.08±0.09)mg/L,优于阳性参照物齐墩果酸(IC_(50)=(1.27±0.19)mg/L),有望作为抗糖尿病药物先导物;对Cdc25B抑制活性测试中,11个目标分子表现出良好的活性,其中8-A-d、8-C-d和8-D-c抑制活性的IC_(50)值分别为(0.97±0.05)、(1.06±0.03)和(0.94±0.11)mg/L,低于阳性参照物Na_3VO_4(IC_(50)=(1.25±0.14)mg/L),有望作为抗肿瘤药物先导物。     

Theoretical Studies on Aromaticity of Spiro Metallaaromatics of (C10H10M)2-(M=Ni,Pd, Pt)

Aiming to identify the spiro metallaaromatic systems with potential application value, (C₁₀H₁₀M)^2?(M=Ni, Pd, Pt) derivatives were theoretically investigated. (C₁₀H₁₀M)^2?-Iso1, which has two 6-membered rings(6MRs) connected by the M spiro atom, is a 14π-aromatic as a whole plane. (C₁₀H₁₀M)^2?-Iso2 has one 6π-aromatic 5MR and one 10π-aromatic 7MR connected by the spiro atom. The free (C₁₀H₁₀M)^2? dianions could not exist due to their rather high frontier orbital energies, while the neutral (C₁₀H₁₀M)Li₂ compounds are extremely stable against dissociation. Since (C₁₀H₁₀M)Li₂ coumponds are not fully coordinated, they trend to form (C₁₀H₁₀M)Li₄²⁺ dications, or even[(C₁₀H₁₀M)Li₂]_n polymers. Arguably, (C₁₀H₁₀M)^2? planes are not the only examples for spiro metallaaromaticity, their derivatives are also potential material building blocks.     

Design,Synthesis and Anticancer Activity of Shikonin and Alkannin Derivatives with Different Substituents on the Naphthazarin Scaffold

Based on the asymmetric reduction of alkannin ketone derivative 4 by diisopinocampheylchloro-borane(DIP-Cl), a series of shikonin and alkannin derivatives was designed, synthesized and their anticancer activities against various kinds of cell lines were evaluated. The in vitro biological experiments demonstrated that compound S-10, a 5,8-O-dimethyl-1,4-dioxime alkannin derivative, not only displayed excellent antiproliferative activity against cancer cells, but also exhibited low toxicity towards normal cells. It could induce HCT-116 cell apoptosis, but had no impact on the cell cycle. The underlying anticancer mechanism of S-10 is most likely different from other shikonin and alkannin derivatives.     

Design,Synthesis and Anticancer Activity of Novel 6-（Aminophenyl）-2,4-bismorpholino-1,3,5-triazine Derivatives Bearing Arylmethylene Hydrazine Moiety

In an attempt to develop potent and selective anticancer agents,we designed and synthesized a series of novel bis（morpholino-1,3,5-triazine） derivatives beating aylmethylene hydrazine moiety and evaluated their cytotoxicity,in vitro,against H460（non-small-cell lung cancer）,HT-29（human colorectal cancer） and MDA-MB-231（human breast cancer） cell lines.The pharmacological results indicate that all the compounds exhibit enhanced cytotoxicity than BMCL-200908069-1,and six target compounds（7e,7h,7j,9a,9b,9c） were superior to PAC-1 against all the tested cancer cell lines.The most active compound 7j,with IC50（inhibitory concentration 50％）values of 0.75,0.34 and 0.60 μ mol/L against HT-29,H460 and MDA-MB-231 cancer cell lines,was 39-,28-,and 60-fold more potent than BMCL-200908069-1 （29.24,9.52 and 36.21 μmol/L）,respectively.     

Selective derivatisations of resorcarenes - 2. Multiple regioselective ring closure reactions

The condensation of the C-pentyl resorcarene 1 with long chain aliphatic diamines 3a-d and excess formaldehyde leads under high dilution conditions to tetrabenzoxazine derivatives 4a-d in which pairs of adjacent oxazine rings are connected by an aliphatic chain. Six new rings are formed per resorcarene molecule during this reaction in a regioselective way. For one example (4a) the chiral cleft-like structure with C₂ symmetry was proved by single crystal X-ray analysis. Hydrolysis of the oxazine rings gives the secondary amine derivatives 5a,b with C_2v symmetry in high yield.     

Thermogravimetry of some uranium 8-hydroxyquinolates

The thermogravimetric behaviour of UO₂(C₉H₆NO)₂.C₉H₆NOH and [UO₂(C₉H₆NO)₂]₂.C₉H₆NOH prepared by precipitation from homogeneous solution with 8-acetoxy-quinoline has been found to closely resemble that of UO₂(C₉H₆NO)₂.C₉H₆NOH prepared by direct precipitation of uranium^VI with 8-hydroxyquinoline.     

Terpenoids—LXX Structure of dehydrocostus lactone

The structure III assigned to dehydrocostus lactone by Sorm et al. has been supported by converting it into (i) guaiane, C₁₅H₂₈ (I) and (ii) s-guaiazulene and chamazulene in fairly high yield from sone of its derivatives. The lactol XII, obtainable from III gives four different products (XIII, XIV, XVIII and XXIV) when subjected to Huang-Minlon reduction at 135° and 170° respectively. The dienic monol (XVIII) the structure of which is supported by UV and NMR spectra, furnished a hydrocarbon C₁₅H₂₆ XXVIII, when subjected to metal amine reduction indicating the presence of an allylic hydroxyl in it, which proves that the lactone attachment in III is at C₆–C₇.     

Mesogenic Unsymmetric dimers containing cholesteryl ester and tolane moieties

Among unsymmetric oligomesogens, chiral dimers formed by connecting a cholesteryl ester fragment with various aromatic mesogenic cores through a polymethylene spacer have been attracting much attention due to their remarkable thermal behaviour. In particular, dimers containing a diphenylacetylene segment having an alkoxy chain have shown interesting mesomorphic behaviour. In view of this a new series of unsymmetric dimers consisting of a diphenylacetylene moiety having an alkyl chain and a cholesteryl ester unit joined through a paraffinic spacer have been synthesized and their liquid crystalline properties characterized. The lengths of the central methylene spacer (C₃, C₄, C₅ and C₇) as well as that of the alkyl chain (n-butyl, n-pentyl, n-hexyl and n-heptyl) have been varied to establish structure-property relationships. These investigations have revealed that all the dimers exhibit smectic A, twist grain boundary and chiral neamtic (N*) phases with the exception of one of the dimers for which only the N* phase was observed. Some differences in the mesomorphic properties of the unsymmetric dimers containing odd or even parity methylene spacers have been observed. The majority of dimers having an even (C₄) parity paraffinic spacer show a blue phase while the dimers with odd (C₃, C₅ and C₇) parity spacers exhibit the chiral smectic (SmC*) phase. In some cases, the SmC* phase exists well below (-60°C) and above room temperature.     

Supported transition-metal catalysts for the C---C coupling reaction between ethene and diazoalkanes

The preparation of a series of immobilized transition-metal catalysts are reported. The catalysts were obtained by chemisorption of either rhodium(I) or iridium(I) complexes [MX(C₂H₄)₂]_n (M = Rh, Ir; X = Cl, OAc, acac, f₃-acac, f₆-acac) on SiO₂ or MgO supports. The oxides were also activated by SiCl₄ or TiCl₄ to give support materials in which the acidic nature of the surface is substantially increased. The activity of the immobilized catalysts was tested, particularly in the reaction of ethene with diphenyldiazomethane which yields a mixture of 1.1-diphenylpropene (8) and 1.1-diphenylcyclopropane (9). It was found that the most active and most selective (highest ratio 8:9) catalyst B1 was formed support material B (SiO₂ activated by SiCl₄) and [RhCl(C₂H₄)₂]₂ (1) and that both the activity and selectivity of B1 was comparable with that of complex 1 in solution. In contrast, the supported catalysts A2, D2 and A3, D3 obtained from [Rh(OAc)(C₂H₄)₂]₂ (2) and [Rh(acac)(C₂H₄)₂] (3) were less active than compounds 2 and 3 in solution. The immobilized catalysts A6, A7, D7 and E7, which were generated from the chloro- and acetatoiridium(I) complexes [IrCl(C₂H₄)₂]₂ (6) and [Ir(OAc)(C₂H₄)₂]₂ (7), possessed a lower activity than the rhodium counterparts. With diazoalkanes other than Ph₂CN₂, the activity of the supported catalyst B1 was partly higher and partly lower than that of complex 1 in the homogeneous phase.     

Complex formations of silver(I) trifluoroacetate and trifluoromethanesulfonate with benzene and cyclohexene

An apparatus for measurements of equilibrium ligand vapor pressure has been applied in order to determine the stoichiometry of benzene and cyclohexene complexes of silver(I) trifluoroacetate (AgCF₃CO₂) and silver(I) trifluoromethanesulfonate (silver(I) triflate, AgCF₃SO₃) in the solid state. It has been found that the equilibrium leads the formation of such complexes as: (AgCF₃CO₂)₂(C₆H₆), (AgCF₃CO₂)₂(C₆H₁₀), (AgCF₃CO₂)₂(C₆H₁₀)₃, (AgCF₃SO₃)₂(C₆H₆), (AgCF₃SO₃)(C₆H₆), (AgCF₃SO₃)(C₆H₁₀) and (AgCF₃SO₃)(C₆H₁₀)₂. The temperature dependence of the gas-solid equilibrium ligand pressure has also been examined for these complexes, and the enthalpy and entropy changes according to the following complex dissociation reactions were estimated: (AgCF₃CO₂)L_m (s) AgCF₃CO₂ (s)+mL (g): and (AgCF₃SO₃)L_n (s) AgCF₃SO₃ (s)+nL (g), where L's are benzene and cyclohexene. On the basis of the thermodynamic data obtained, the effects of the counter anion as well as the ligand on the complex stability are discussed.     

十八烷基醚型高效液相反相色谱填料的制备

反相填料在生物学、化学和药物工业等领域应用广泛 ,大量新的性能优良的反相柱不断投入市场[1,2 ].反相固定相除选择烷基链长度在Ｃ1Ｃ18之间外 ,不同疏水配基及结构特征也可提供不同的选择性 .通常调节流动相的组成 ,可以实现对分离过程的优化 ,但在实际应用中 ,发展不同类型的柱可更有效地分离相似或相近的化合物[3 ,4].本文报道了一种制备Ｃ18烷基醚型反相ＨＰＬＣ填料的新工艺[5 ],并对所得填料进行了初步的色谱性能评价 .1　实验部分1 .1　试剂与仪器　自制球形硅胶 (Ｓｉｎｏｐａｋ Ｓ ,粒径 5μｍ ,平均孔径 1 1ｎｍ ,比表面积 1 70…     

非离子表面活性剂Brij 30诱导离子液体型表面活性剂C16imC8Br蠕虫状胶束向凝胶的转变

Wormlike micelles and low-molecular-weight hydrogels are composed of three-dimensional networks that endow them with viscoelasticity, but their viscoelastic properties are markedly different. The viscosity of wormlike micelles is attributed to a transient network, while that of gels is due to a stable network. Under certain conditions, wormlike micelles can undergo transition to gels with an increase in the density of the network. In our previous study, we found that the wormlike micelle formed by the ionic liquid-type surfactant 1-hexadecyl-3-octyl imidazolium bromide ([C₁₆imC₈]Br) without any additive has high viscoelasticity. The inclusion of a nonionic surfactant polyoxyethylene lauryl ether (Brij 30) is expected to enhance the viscoelasticity of [C₁₆imC₈]Br wormlike micelles via electrostatic shielding and strong hydrophobic interactions, which may be the driving factor for the wormlike micelle-to-gel structural transition. The morphology and viscoelasticity of [C₁₆imC₈]Br wormlike micelles with Brij 30 were studied as a function of concentration by rheological measurements and freeze-fracture transmission electron microscopy. The thermal stability and gel-sol transition temperature of the Brij 30/[C₁₆imC₈]Br gels were studied using rheology. The interaction between Brij 30 and [C₁₆imC₈]Br was studied by zeta potential measurements and nuclear magnetic resonance (NMR) spectroscopy. Upon the inclusion of Brij 30 into the [C₁₆imC₈]Br wormlike micelles, the viscoelasticity of the Brij 30/[C₁₆imC₈]Br samples first increased and then decreased with an increase in the Brij 30 concentration, at different initial concentrations of [C₁₆imC₈]Br. At a certain Brij 30 concentration, the Brij 30/[C₁₆imC₈]Br samples rheologically behaved as a gel. The maximum viscoelasticity of the [C₁₆imC₈]Br (4.06% (w))/Brij 30 gel was observed at a Brij 30/[C₁₆imC₈]Br molar ratio of 4.55. The viscoelasticity of the Brij 30/[C₁₆imC₈]Br gels was positively correlated with the activation energy of the gels. The gel-sol transition temperature of the Brij 30/[C₁₆imC₈]Br gels also increased first and then decreased with an increase in the Brij 30 concentration. The highest gel-sol transition temperature of the Brij 30/[C₁₆imC₈]Br (4.06% (w)) gel was observed at a Brij 30/[C₁₆imC₈]Br molar ratio of 2.93. The Brij 30 concentration had a notable impact on the viscoelasticity, thermal stability, and gel-sol transition temperature of the Brij 30/[C₁₆imC₈]Br gels. The zeta potential and ¹H NMR measurements revealed that the neutral Brij 30 molecules are inserted into the palisade layer of the [C₁₆imC₈]Br wormlike micelles via hydrophobic interactions. This decreased the electrostatic repulsion between the [C₁₆imC₈]Br headgroups, which in turn induced the rapid growth of wormlike micelles and the formation of a stiffer network structure. Finally, the wormlike micelles underwent a structural transition to gels. The obtained results would aid in better understanding the relationship between wormlike micelles and gels, and may be of potential value for industrial and technological applications.     

Characterization of the first mixed-valent liquid-crystalline materials. Synthesis and structural properties of new binuclear ruthenium carboxylates

The syntheses and structural properties of new binuclear ruthenium (II, III) complexes with long chain carboxylates, of general formula Ru₂(RCO₂)₄X (R = C₈H₁₇, C₁₁H₂₃ and X = C1, RCOO), are reported. The thermodynamic behaviour of these compounds is strongly influenced by the nature of the counterion X. The chloro complexes (X = CI) are not mesomorphic whereas the carboxylato species (X = RCOO) are shown to exhibit a thermotropic columnar mesophase, thus providing the first example of a mixed-valent liquid-crystalline material.     

Theoretical study of tricyclo[3,3,1,1]decane, tricyclo[3,3,1,1]decsilane molecules and their halogen derivatives, C10H12X4 and Si10H12X4 (X=F, Cl, Br, I)

The B3LYP/3-21G* ab initio molecular orbital method from the program package was applied to study tricyclo[3,3,1,1^3,7]decane and tricyclo[3,3,1,1^3,7]decsilane molecules and their halogen derivatives (1,3,5,7-tetrahalotricyclo[3,3,1,1^3,7]decane and 1,3,5,7-tetrahalotricyclo[3,3,1,1^3,7]decsilane, C₁₀H₁₂X₄ and Si₁₀H₁₂X₄ respectively). The optimized structures of these compounds were obtained. Ionization potentials, HOMO and LUMO energies, energy gaps, heats of formation, atomization energies and vibration frequencies were calculated. The calculations indicate that these molecules are stable and have T_d symmetry. Tricyclo[3,3,1,1^3,7]decsilane and its halogen derivatives (Si₁₀H₁₂X₄) are found to have higher conductivity than tricyclo[3,3,1,1^3,7]decane and its halogen derivatives (C₁₀H₁₂X₄). 1,3,5,7-Tetrafluorotricyclo[3,3,1,1^3,7]decane (C₁₀H₁₂F₄) and 1,3,5,7-tetrafluorotricyclo[3,3,1,1^3,7]decsilane (Si₁₀H₁₂F₄) were found to be the easiest compounds to form and the most difficult to dissociate of all 1,3,5,7-tetrahalotricyclo[3,3,1,1^3,7]decane and 1,3,5,7-tetrahalotricyclo[3,3,1,1^3,7]decsilane compounds, respectively.     

Homochiral cyclopentane-based C1-symmetric P,P ligands C5H8(PPh2)(PR2) from C2-symmetric C5H8(PCl2)2

Treatment of 1,2-trans-C₅H₈(PCl₂)₂ with 1,2-C₂H₄(NHPr-i)₂ gave the C₂-symmetric perhydro-1,6,2,5-diazaphosphocine C₅H₈{P(Cl)N(Pr-i)CH₂}₂-cyclo, which produced dissymmetric C₅H₈(PPh₂){P[N(Pr-i)CH₂]₂-cyclo} on further reaction with PhMgBr. Cleavage of the P---N bonds with gaseous HCl afforded C₅H₈(PPh₂)(PCl₂), which was converted to C₅H₈(PPh₂){P(OPh)₂}₂ by reaction with phenol. All chiral P,P derivatives were obtained as racemates as well as resolved (1R,2R)- and (1S,2S)-enantiomers.