6′-对位取代苯乙烯基吲哚啉螺吡喃的合成

利用2-亚甲基吲哚啉和取代水杨醛缩合得到十三种新的烷基苯乙烯基吲哚啉螺苯并吡喃。在苯并吡喃部分含有硝基的螺吡喃显示出逆光致变色行为,其它的则为普通光致变色化合物。同时,结果表明,化合物异构体的稳定性不仅取决于化合物本身的结构,而且还取决于介质环境的影响。     

Photochromism of spirobenzopyran in the membrane of surfactant vesicle and in the cavity of cyclodextrins

Photochromic reaction of water insoluble 1,3,3-trimethyl-6-nitrospiro[2H-1-benzopyran-2,2-indoline] (SP) was studied in water with the aid of vesicles and -cyclodextrin (-CD). In both systems, the photochromic reaction of SP was observable in spite of the low solubility of SP in water. In order to examine the microenvironment around the SP and the reaction product, photomerocyanin (MC), in those systems, the spectrum of MC was measured in various organic solvent of various polarity. Decreasing the polarity of the solvent decreased the peak absorbance and shifted the peak wavelength to the long wavelengths. When the vesicles were used, the reactant, SP, and the product, MC, were solubilized in different regions of different polarity. The reaction substrate was then supposed to have moved from the hydrophobic region of the membrane to the hydrophilic one after the photoisomerzation. The photochromic reaction of SP in the presence of -CD was slower than in the vesicles and faster than that in methanol. The polarity in the vesicular membrane and the limited rotation of the reactant in the cavity of -CD may have influenced the reaction rate. The prolonged light irradiation period resulted in a simultaneous photoreaction and polymerization, producing some unknown side reaction.     

‘Purposive’ Molecular Design for Multifunctional Artificial Receptors

This account describes recent examples of multifunctional artificial receptors, which demonstrates our approach to purposive molecular design. The paper is divided into two parts. The first deals with novel crowned spirobenzopyrans as dual-mode signal transducers. The new crowned spirobenzopyrans complement previous crowned spirobenzopyrans from the viewpoint of molecular devices, and a detailed comparison between them is given. The second part is concerned with polypyridine-macrocyclic structures as ribofuranoside receptors. The design of the ribofuranoside receptors was based on the multipoint hydrogen bond complementarity between the receptors and methyl -(d)-ribofuranoside. The binding affinity of the receptors was very high, so that even native ribose was extracted by them into nonpolar solvents.     

Studies on PNPP Hydrolysis Catalyzed by Schiff Base Cobalt（Ⅱ） Complexes Containing Benzoaza-15-crown-5

Three novel Schiff base cobalt（Ⅱ） complexes containing benzoaza-15-crown-5, CoL^1, CoL^2 and CoL^3 were synthesized and characterized, and these complexes were used in catalytic hydrolysis of carboxylic ester （PNPP, p-nitrophenyl picolinate） as mimic hydrolytic metalloenzyme. The analysis of specific absorption spectra of the hydrolytic reaction systems indicated that the catalytic hydrolysis involved the key intermediates formed by PNPP with cobalt（Ⅱ） complexes. The CoL^3 bearing the electron withdrawing group shows better catalytic activity due to its stabilization effect on active species MLS^-. The catalytic mechanism of PNPP hydrolysis was also proposed. The kinetic parameter of PNPP catalytic hydrolysis has been calculated and the activation energy for the catalytic hydrolysis is 43.69, 39.76 and 35.44 kJ·mol^-1, respectively.     

冠醚螺吡喃化合物的合成和光致变色性质

合成了四个新的6位带不同取代基的含冠醚结构单元吲哚啉螺苯并吡喃化合物(5a-5d),研究了其光致变色性质和离子诱导光致变色作用及取代基的影响。结果表明冠醚能稳定螺吡喃开环形式,碱金属离子对冠醚螺吡喃的生色有诱导作用;6位为吸电子基团时,螺吡喃开环形式的稳定性增加,而6位为推电子基团时,螺吡喃开环形式的稳定性降低。另外,就稳定螺吡喃开环体的作用来说,吲哚啉环上的取代基效应和苯并吡喃环上的正好相反。     

Review on recent and advanced applications of monoliths and related porous polymer gels in micro-fluidic devices

This review critically summarises recent novel and advanced achievements in the application of monolithic materials and related porous polymer gels in micro-fluidic devices appearing within the literature over the period of the last 5 years (2005-2010). The range of monolithic materials has developed rapidly over the past decade, with a diverse and highly versatile class of materials now available, with each exhibiting distinct porosities, pore sizes, and a wide variety of surface functionalities. A major advantage of these materials is their ease of preparation in micro-fluidic channels by in situ polymerisation, leading to monolithic materials being increasingly utilised for a larger variety of purposes in micro-fluidic platforms. Applications of porous polymer monoliths, silica-based monoliths and related homogeneous porous polymer gels in the preparation of separation columns, ion-permeable membranes, preconcentrators, extractors, electrospray emitters, micro-valves, electrokinetic pumps, micro-reactors and micro-mixers in micro-fluidic devices are discussed herein. Procedures used in the preparation of monolithic materials in micro-channels, as well as some practical aspects of the micro-fluidic chip fabrication are addressed. Recent analytical/bioanalytical and catalytic applications of the final micro-fluidic devices incorporating monolithic materials are also reviewed.     

PNPP Cleavage Catalyzed by Schiff Base Mn(III) Complexes Containing Polyether Side Chains in CTAB Micellar Solutions

Two Schiff base Mn(III) complexes containing polyether side chain were synthesized and characterized. The catalytic hydrolysis of p‐nitrophenyl picolinate (PNPP) by the two complexes in the buffered CTAB micellar solution in the pH range of 6.60–8.20 was investigated kinetically in this study. The influences of acidity, temperature, and structure of complex on the catalytic cleavage of PNPP were also studied. The mechanism of PNPP hydrolysis catalyzed by Schiff base manganese(III) complexes in CTAB micellar solution was proposed. The relative kinetic and thermodynamic parameters were determined. Comparied with the pseudo‐first‐order rate constant (k ₀) of PNPP spontaneous hydrolysis in water, the pseudo‐first‐order rate constants (k _obsd) of PNPP catalytic hydrolysis are 1.93×10³ fold for MnL¹ ₂Cl and 1.06×10³ fold for MnL² ₂Cl in CTAB micellar solution at pH=7.00, T=25°C, and [S]=2.0×10^?4mol · dm^?3, respectively. Furthermore, comparing the k _obsd of PNPP catalytic hydrolysis by metallomicelles with that of PNPP hydrolysis catalyzed only by metal complexes or CTAB micelle at the above‐mentioned condition, metallomicelles of MnL₂(L=L¹, L²) Cl/CTAB exhibit notable catalytic activities for promoting PNPP hydrolysis, and MnL¹ ₂Cl/CTAB system is superior in promoting cleavage of PNPP relative to MnL² ₂Cl/CTAB system under the same experimental conditions. The results indicate that the rate of PNPP catalytic cleavage is influenced by the structures of the two complexes, the acidity of reaction systems, and the solubilization of PNPP in CTAB micelles.     

Synthesis of 2‐Spironaphtho[2,3‐b]pyranoquinones

A convenient procedure for the synthesis of 2‐spirobenzopyranoquinone 5 and its application to the preparation of spironaphtho[2,3‐b]pyranoquinones 6 and 7 is described.     

Hydrolysis of Bis(4‐Nitrophenyl) Phosphate Catalyzed by Metallomicelle Made Up of the Crowned Schiff Base Complex as Synthetic Hydrolase

A crowned Schiff base ligand and its cobalt(II) and manganese(III) complexes were synthesized and characterized, and the metallomicelles made from the complexes and micelles (Brij35, LSS, CTAB) were investigated to catalyze the hydrolysis of bis(4‐nitrophenyl) phosphate (BNPP). A kinetic mathematical model for simulating enzyme catalyzing reaction was proposed and employed to analyze the mechanism of BNPP catalytic hydrolysis. Michanelis constant and the apparent active energy for the catalytic reaction were calculated. The kinetic studies showed that the metallomicelle made from the micelle and crowned Schiff base transitional metal complexes is an effective mimetic hydrolytic enzyme for BNPP catalytic hydrolysis.     

Synthesis of Long-Chain SpirobenzopyransBearing a Monoazacrown ether

Thephotochromicpigmentsinthechloroplastandinthephotoreceptorcellofthevisionsystemhaveamonolayerorganization'.Itisknownthatthemonolayerassembliesfavourtheenergetictransformations.Forthevisionprocess,light-inducedisomerizationofretinallinkedtoopsintrig...