新型荧光化学敏感器的合成及性质研究

分子识别是超分子化学的一个重要方面.它是分子传递和酶催化的基础.以分子识别为基础,设计和合成了有光谱响应的荧光化学敏感器和离子显色试剂,在生物化学、临床医学、环境科学等与人类生命科学密切相关的领域中有着很强的应用背景.本论文系统总结了环糊精对有机分子的包结特征和包结作用对客体分子光物理性质的影响,以及用荧光发色团化学修饰的环糊精分子在识别研究中的发展状况.考虑到当前分子识别研究中的另一问题,即发展对阴离子物种有选择性响应的荧光化学敏感器和显色试剂,本论文还总结了目前在设计和合成阴离子接受体方面的发展状况和特点.本论文工作正是从以下两个方面进行了研究.     

[2+2]型苯并咪唑环番的一锅法合成

超分子化学是当今化学中发展迅速、极具前景的研究领域.分子识别是形成超分子化合物的基础.环番由于兼备冠醚、环糊精和多齿配体的一些特性,在分子识别、离子识别、超分子催化、模拟酶、分子自组装、材料科学等方面得到了广泛关注.     

卟啉及卟啉衍生物的应用

近年来,卟啉及卟啉衍生物在显色反应、分子识别、催化合成反应等领域中有很广泛的应用。文章就卟啉及卟啉衍生物在分析化学、生命科学和化学合成方面的研究发展作一简要介绍,并提出卟啉化合物今后的发展方向。     

分子印迹技术用于模拟酶及分子反应器的研究进展

分子印迹技术是制备特异性分子识别材料的新技术. 分子印迹聚合物(Molecularly-imprinted polymer, MIP)具有可同酶相媲美的选择性识别能力, 能够催化手性及区域选择性的反应, 是一种新型的分子反应器; 同时MIP具有良好的化学和物理稳定性, 因而在替代酶用于某些苛刻条件下的催化反应方面有良好的应用前景. 就近年来利用MIP模拟酶催化有机合成反应, 以及利用MIP作为分子反应器反面的研究进展进行了综述.     

新型杯[4]芳烃衍生物的合成及其对镧系金属离子的识别研究

超分子化学是与材料化学、信息科学和生命科学等学科紧密相关的一门交叉学科, 近年来得到了人们越来越多的关注. 分子识别是超分子化学的核心研究内容之一, 也是生命体系中普遍存在的现象. 目前分子识别的主体化合物有3代: 冠醚、 环糊精和杯芳烃. 杯芳烃因具有空腔大小可调、构象可变换、易于化学修饰和既是离子受体又是分子受体等特点, 而成为近年来的研究热点.     

二维分子组装的竞争性手性诱导

正手性分子组装是化学、材料、生命科学等领域研究的重要课题之一。研究分子组装过程的手性诱导和控制,对手性组装结构及材料的设计构筑及其在分子识别、分离、催化、不对称光学等领域的应用具有指导意义,也有助于对自然界中手性     

环糊精-卟啉超分子体系的构筑及应用进展

环糊精具有分子识别和选择包结客体分子的独特性质,而卟啉具有模拟酶催化、电子转移和光能转移等功能,本工作通过对环糊精-卟啉超分子体系构筑方式的介绍,详细综述了环糊精-卟啉超分子体系在模拟酶催化、生命科学、药物控释、电子转移过程等方面的应用,认为环糊精-卟啉超分子体系具有卟啉和环糊精双重性质的优点,而以键联环糊精-卟啉为主体分子构筑的超分子体系能更有效地模拟生物酶,表现出优异的区域和立体选择性,在仿生催化方面将具有更广泛的应用前景.     

基于硅材料的分子印迹聚合物的制备及应用*

分子印迹聚合物因制备简单、稳定性好、且具有分子识别功能使其在色谱分离、固相萃取、化学传感、模拟酶催化等方面有了广泛的应用。近年来,基于硅的分子印迹聚合物发展较为快速。本文主要介绍了以硅为母体材料和以硅为基质材料的分子印迹聚合物的制备及分子识别性质研究,并对其应用进行了分类,在此基础上对其将来的发展进行了展望。     

化学及生物体系中的分别识别*

分子识别的目标是研究分子间专一性地相互作用, 这在化学及生命过程中起着非常重要的作用。本文综述了分子识别的机制及其在化学、生命科学、材料、信息等有关学科中的应用。     

基于有机小分子的焦磷酸根荧光探针研究进展

焦磷酸根(PPi)作为一种重要的生物功能阴离子在生命科学、环境科学、药物领域和化学过程等方面起着非常重要的作用.鉴于荧光分析具有操作简便、灵敏度高等突出优点,设计合成高效的PPi荧光探针成为近年来超分子化学研究的热点之一.综述了近年来PPi荧光识别与传感的多种设计策略与原理,主要包括基于荧光增强或淬灭型识别,激基缔合物识别,荧光指示剂置换,静电或氢键作用识别等.DPA-金属离子络合物,尤其是DPA-Zn2+络合物,作为识别基团对PPi有着显著的亲和性和选择性识别能力.DPA-Zn2+络合物与多种荧光团或者荧光指示剂组合而形成的化学传感体系已经被广泛应用于PPi荧光识别与传感.     

The energy pump and the origin of the non-equilibrium flux of the dynamical systems and the networks

The global stability of dynamical systems and networks is still challenging to study. We developed a landscape and flux framework to explore the global stability. The potential landscape is directly linked to the steady state probability distribution of the non-equilibrium dynamical systems which can be used to study the global stability. The steady state probability flux together with the landscape gradient determines the dynamics of the system. The non-zero probability flux implies the breaking down of the detailed balance which is a quantitative signature of the systems being in non-equilibrium states. We investigated the dynamics of several systems from monostability to limit cycle and explored the microscopic origin of the probability flux. We discovered that the origin of the probability flux is due to the non-equilibrium conditions on the concentrations resulting energy input acting like non-equilibrium pump or battery to the system. Another interesting behavior we uncovered is that the probabilistic flux is closely related to the steady state deterministic chemical flux. For the monostable model of the kinetic cycle, the analytical expression of the probabilistic flux is directly related to the deterministic flux, and the later is directly generated by the chemical potential difference from the adenosine triphosphate (ATP) hydrolysis. For the limit cycle of the reversible Schnakenberg model, we also show that the probabilistic flux is correlated to the chemical driving force, as well as the deterministic effective flux. Furthermore, we study the phase coherence of the stochastic oscillation against the energy pump, and argue that larger non-equilibrium pump results faster flux and higher coherence. This leads to higher robustness of the biological oscillations. We also uncovered how fluctuations influence the coherence of the oscillations in two steps: (1) The mild fluctuations influence the coherence of the system mainly through the probability flux while maintaining the regular landscape topography. (2) The larger fluctuations lead to flat landscape and the complete loss of the stability of the whole system.     

New study of the stability and of the spectroscopy of the molecular anions NCO- and CNO-

Using highly correlated wave functions, the ground and the low lying excited states of the molecular NCO(-) and CNO(-) anions have been reinvestigated. The stability of the electronic ground state of the two isomers with respect to dissociation and to electron detachment has been checked along the isomerization pathway. The regions of stability of the excited electronic states have been analyzed and identified and it is shown that only the ground state is stable and the corresponding potential energy surface presents three equilibrium positions. The rovibronic spectroscopy of the X (1)Σ(+) state of both NCO(-) and CNO(-) isomers has been determined by a variational approach leading to remarkable agreement with experimental data.     

Analysis and assessment of the occurrence, the fate and the behavior of nanomaterials in the environment

Nanomaterials have one dimension <100 nm and possess physico-chemical properties dictated by their unusually small size, large surface area, shape and chemical composition. New properties of nanomaterials have boosted their production and industrial applications in many fields (e.g., microelectronics, catalysis, fuel cells, materials science, textiles, biotechnology and medicine). In biomedical fields, nanomaterials are of the appropriate dimensions to interact with biological matter. However, they may also have negative effects on biological systems. Nanotechnology is a major, innovative, scientific and economic growth area, but the increasing production and use of nanomaterials have led to calls for more information regarding the potential impacts that their release may have on human health and the environment.This review addresses analytical approaches for characterization and quantification of nanomaterials in the environment and recent studies on their occurrence, fate and behavior.     

Influence of the molecular structure and the nature of the solvent on the absorption and fluorescence characteristics of rhodamines

A study of the equilibrium of the molecular forms of rhodamine 19 in aqueous and ethanolic solution is carried out by determining the absorption and fluorescence characteristics of the zwitterionic and the cationic forms of the dye. The optical properties of rhodamine 19 are compared with those obtained for rhodamine 6G and also with those previously reported for rhodamine 3B and for the molecular forms of rhodamine B in water and ethanol. Different aspects of the molecular structure of the rhodamines and solvent effects are discussed, as well as their influence on the photophysical properties of the rhodamines. The aggregation of the molecular forms of rhodamine 19 is also studied in water and ethanol.     

Isolation and identification of the anti-isohumulones and the anti-acetylhumulinic acids

The anti-isohumulones [5-(3-methylbutanoyl)-2-(3-methylbut-2-enyl)-4-hydroxy-4-(4-methylpent-3-enoyl)-cyclopentane-1,3-diones] and the anti-acetylhumulinic acids [5-(3-methylbutanoyl)-2-(3-methylbut-2-enyl)-4-ethanoyl-4-hydroxy-cyclopentane 1,3-diones] have been isolated from an isomerisation reaction mixture of humulone [2-(3-methylbutanoyl)-4,6-di(3-methylbut-2-enyl)-6-hydroxy-cyclohexane-l,3,5-trione] by counter-current distribution and identified by spectroscopic techniques. The formation mechanism is presented and the stereochemical consequences are discussed. The anti-isohumulones are the most bitter hop compounds presently known.     

Synthesis and pharmacological effects of the enantiomers of the N-phenethyl analogues of the ortho and para e- and f-oxide-bridged phenylmorphans

The N-phenethyl analogues of (1R*,4aR*,9aS*)-2-phenethyl-1,3,4,9a-tetrahydro-2H-1,4a-propanobenzofuro[2,3-c]pyridin-6-ol and 8-ol and (1R*,4aR*,9aR*)-2-phenethyl-1,3,4,9a-tetrahydro-2H-1,4a-propanobenzofuro[2.3-c]pyridin-6-ol and 8-ol, the ortho- (43) and para-hydroxy e- (20), and f-oxide-bridged 5-phenylmorphans (53 and 26) were prepared in racemic and enantiomerically pure forms from a common precursor, the quaternary salt 12. Optical resolutions were accomplished by salt formation with suitable enantiomerically pure chiral acids or by preparative HPLC on a chiral support. The N-phenethyl (-)- para-e enantiomer (1S,4aS,9aR-(-)-20) was found to be a mu-opioid agonist with morphine-like antinociceptive activity in a mouse assay. In contrast, the N-phenethyl (-)-ortho-f enantiomer (1R,4aR,9aR-(-)-53) had good affinity for the mu-opioid receptor (K(i) = 7 nM) and was found to be a mu-antagonist both in the [(35)S]GTP-gamma-S assay and in vivo. The molecular structures of these rigid enantiomers were energy minimized with density functional theory at the level B3LYP/6-31G* level, and then overlaid on a known potent mu-agonist. This superposition study suggests that the agonist activity of the oxide-bridged 5-phenylmorphans can be attributed to formation of a seven membered ring that is hypothesized to facilitate a proton transfer from the protonated nitrogen to a proton acceptor in the mu-opioid receptor.     

Phospholipid and fatty acid compositions of the lipids of the eggs and caterpillars of the silkworm,and of artificial diets and their components

The lipids of silkworm eggs in the period of diapause and embryonic and postembryonic development, of artificial feeds, and of the main lipid-containing components of artificial nutrient media have been investigated.     

Phospholipid and fatty acid compositions of the lipids of the eggs and caterpillars of the silkworm, and of artificial diets and their components

The lipids of silkworm eggs in the period of diapause and embryonic and postembryonic development, of artificial feeds, and of the main lipid-containing components of artificial nutrient media have been investigated.Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 192–197, March–April, 1994.