meso—苯基四苯并卟啉的合成和光谱性能研究（II）

本文将ｍｅｓｏ－苯基四苯并卟啉锌（Ｚｎ－ＰｎＴＢＰｎ＝１￣４）在酸性条件下脱锌，获得了不含金属离子的ｍｅｓｏ－苯基四苯并卟啉（Ｈ２－ＰｎＴＢＰｎ＝１￣４）。研究了它们的吸收光谱、荧光光谱及在溶液状态下的瞬态光谱特性，并对照相应的锌卟啉，讨论了两者之间的光谱差异。     

meso－苯基四苯并卟啉的合成和光谱性能研究（Ⅱ）

本文将ｍｅｓｏ－苯基四苯并卟啉锌（Ｚｎ－Ｐ_ｎＴＢＰｎ＝１～４）在酸性条件下脱锌，获得了不含金属离子的ｍｅｓｏ－苯基四苯并卟啉（Ｈ_２Ｐ_ｎＴＢＰｎ＝１～４）。研究了它们的吸收光谱、荧光光谱及在溶液状态下的瞬态光谱特性，并对照相应的锌卟啉，讨论了两者之间的光谱差异。     

二溴邻硝基偶氮胂的纯化,性质及其钍络合物的稳定常数

研究了钍的新试剂二溴邻硝基偶氮砷（ＤＢＯＮＡ）的纯化方法和性质。测定的其离解常数（ｐＫａ）、质子化常数（ｌｏｇＫｐ）分别为１０．１７和－４．７５。求得钍络合物的组成为１：２，其积累稳定常数为２７．９８。     

meso—四（4—磺酸基萘基）卟啉与痕量铜显色反应研究

研究了铜（Ⅱ）与ｍｅｓｏ－四（４－磺酸基萘基）卟啉的显色反应，在ｐＨ为２．８５的ＨＣｌ－邻苯二甲酸氢钾缓冲溶液中，铜与ＴＮＰＳ４生成稳定的１：１型黄绿色的配合物，其最大吸收波长为４１８ｎｍ，表面摩尔吸光系数为３．０８×１０＾５·ｍｏｌ＾－１·ｃｍ＾－１。     

一元弱酸表观离解常数pKa的测定

本文依据Ｈｅｌｍｋａｍｐ和Ｊｏｈｎｓｏｎ所提出的实验方法，通过选择易溶于水的弱酸，采用电位滴定法准确测定滴定ＨＡ至一半时溶液的氢离子浓度，得到表观离解常烤ｐＫａ，并通过数学方法计算出经对ｐＫａ，该方法不仅能用于ｐＫａ〈１１．３弱酸，也可以用于ｐＫａ≥１１．３的极弱酸离解常数的测定，具有简单，快速，准确的特点。     

4,8-二磺酸萘偶氮氯磺酚离解作用的研究及其与Nb(V)络合物稳定常数的测定

用电位法研究了新显色剂４，８－二磺酸萘偶氮氯磺酚的离解作用。用分光光度法测定了该试剂的离解常数及其与Ｎｂ（ｖ）形成的组合物的累积稳定常数。离解常数Ｋ６＝２．７０×１０－７、Ｋ７＝６．９４×１０－９．Ｋ８＝９．２４×１０－１２；累积稳定常数１ｇＫ＝３９．４９±０．４０。     

3-羧基苯偶氮氯磺酚离解作用的研究及其与V(Ⅳ)配合物稳定常数的测定

用电位滴定法研究了新显色剂３－羧基苯偶氮氯磺酚的离解作用。用分光光度法测定了该显色剂的离解常数及其与Ｖ（Ⅳ）形成的配合物的稳定常数。离解常数Ｋ５＝２．９２×１０－７、Ｋ６＝４．７８×１０－１０、Ｋ７＝２．３９×１０－１２,表观稳定常数ｌｇＫＳ′＝５．９８±０．４９（Ｐ＝０．９５）。     

新试剂meso—四（3—氟—4—磺基苯）卟啉光度法测定痕量镉的研究

研究了碱性介质中新试剂ｍｅｓｏ－四（３－氟－４磺基苯）卟啉（ｍ－ＦＴＰＰＳ４）与Ｃｄ（Ⅱ）的显色反应条件。不加任何辅助试剂,沸水浴中加热２０ｍｉｎ,ｍ－ＦＴＰＰＳ４与Ｃｄ（Ⅱ）形成灵敏度较高的１１配合物,表观摩尔吸光系数为３．３２×１０５Ｌｍｏｌ－１ｃｍ－１。应用于天然水中痕量Ｃｄ（Ⅱ）的测定,结果满意。     

合成三聚氯氰的氯化和聚合反应宏观动力学研究

利用非等温固定床反应器，研究了三聚氯氰合成的氯化和聚合反应宏观动力学，实验表明氢氰酸与氯气的氯化反应为气相均相反应，而氯氰的聚合反应为吸附在活性炭表面上的氯氰表面反应为控制步骤的气固催化反应。实验测得氯化反应的宏观反应动力学方程为对氢氰酸的一级反应，即（－ｒＡ）１＝２．４５×１０７ｅｘｐ（－２．９０×１０４／ＲＴ）ｃＡ测得聚合反应的宏观动力学方程为（－ｒＡ）２＝ｋ［ｐ３Ａ－ｐＲ／Ｋｐ］／［１＋ＫＡｐＡ＋ＫＲｐＲ］３ｋ＝４．０×１０７ｅｘｐ（－４．３５×１０４／ＲＴ）Ｋｐ＝６．７６×１０－２３ｅｘｐ（３．５２×１０５／ＲＴ）ＫＡ＝４．０×１０３ｅｘｐ（－３．３９×１０４／ＲＴ）ＫＲ＝１．０５×１０３ｅｘｐ（－５．０２×１０４／ＲＴ     

meso—四（4—羟基苯基）卟吩与钯离子显色反应的研究及应用

首次系统研究了非水溶性ｍｅｓｏ－四（４－羟基苯基）卟吩（ｍｅｓｏ－ｔｅｔｒａｋｉｓ（４－ｈｙｄｒｏｘｙｐｈｅｎｙｌ）ｐｏｒｐｈｉｎｅ，简称Ｔ（４－ＨＰ）Ｐ）与钯（Ⅱ）的显色反应条件及有机溶剂的增敏作用。在Ｌ－抗坏血酸、表面活性剂存在下，沸水浴中加热１５ｍｉｎ，钯（Ⅱ）与Ｔ（４－ＨＰ）Ｐ形成稳定的１＋１配合物。ε４１９＝２．７２×１０５Ｌｍｏｌ－１ｃｍ－１，加入丙酮后，ε４２０＝１．４６×１０６Ｌｍｏｌ－１ｃｍ－１，是目前报道的分光光度法中测钯（Ⅱ）最灵敏的方法之一。试验了１７种离子的干扰影响。用此法测定了硅载体钯催化剂中钯的含量，回收率达９５％～９９％。     

Aggregation of Tetrakis(4-methylpyridyl)porphyrin and tetrakis(4-sulphonatophenyl)porphyrin in water

The homo- and heteroaggregation of two oppositely charged water soluble porphyrins, tetrakis(4-methylpyridyl)porphyrin, TMPyP and tetrakis(4-sulphonatophenyl) porphyrin, TSPP has been studied by means of absorption and fluorescence spectroscopy in phosphate buffered saline. All experimental results on TSPP are consistent with a monomerdimer equilibrium (ΔH = −19.6 and ΔS = 19.3 kJ mole⁻¹). The absorption spectrum of the TSPP dimer was obtained from a global fit of a set of spectra to the monomer dimer model. TMPyP does not aggregate at concentrations up to 10⁻⁴M . Changes in the fluorescence spectrum of TMPyP upon dilution are due to adsorption phenomena. 1:1 heteroagregates of both porphyrins cannot be characterized in water solution due to extreme small solubility. A 2:1 heteroaggregate is detectable in solution. It is proposed to exploit the extreme small solubility of heteroaggregated oppositely charged porphyrins to increase the selective retention of porphyrins provided there is an initial selectivity of ether component.     

Porphyrin derivatives for telomere binding and telomerase inhibition

The capacity of G-quadruplex ligands to stabilize four-stranded DNA makes them able to inhibit telomerase, which is involved in tumour cell proliferation. A series of cationic metalloporphyrin derivatives was prepared by making variations on a meso-tetrakis(4-N-methyl-pyridiniumyl)porphyrin skeleton (TMPyP). The DNA binding properties of nickel(II) and manganese(III) porphyrins were studied by surface plasmon resonance, and the capacity of the nickel porphyrins to inhibit telomerase was tested in a TRAP assay. The nature of the metal influences the kinetics (the process is faster for Ni than for Mn) and the mode of interaction (stacking or external binding). The chemical alterations did not lead to increased telomerase inhibition. The best selectivity for G-quadruplex DNA was observed for Mn-TMPyP, which has a tenfold preference for quadruplex over duplex.     

脂肪族醇的酸碱离解常数(pKa)的预测研究

酸碱离解常数(pKa)在理解受体与药物反应和药物如何选择辅料上起着重要的作用。因此,在药物前期的开发中,能有效地预测pKa值可很好地降低开发成本,降低资源消耗。本文通过运用定量构效关系的方法(QSAR)对脂肪醇的数据库展开研究,以进行pKa值的预测。一共选用了253种各类描述符,包含原子键的性质的描述符48个,分子整体描述符205个,其中重点描述符为原子键的性质类描述符。采取多元线性回归的方法对数据进行研究。该预测模型能取得较好的效果,可以应用于药物的前期开发中。     

Novel meso-substituted porphyrins: Synthesis, characterization and photocatalytic activity of their TiO2-based composites

Two series of novel meso-substituted porphyrins, namely 5,10,15,20-tetra[4-(3-phenoxy)-propoxy]phenyl porphyrin, the structural analogue 5,10,15,20-tetra[2-(3-phenoxy)-propoxy]phenyl porphyrin and their Co(II) Cu(II) and Zn(II) complexes were synthesized. The compounds were characterized using various spectroscopic techniques and their molecular structure was proposed based on density functional theory calculations. The diverse properties of the porphyrin derivatives result from the different stereochemistry of the particular substituents at the meso site on the macrocycle and are controlled also by the coordinated metal. The ¹H NMR spectrum of the free-base porphyrin showed a complicated spin-splitting. The photocatalytic activities in degradation of 4-nitrophenol were investigated using polycrystalline TiO₂ impregnated with the porphyrins and metalloporphyrins. The Cu(II) porphyrin was a more effective sensitizer than other metal containing compounds (M = Co, Zn) as well as the free-base. Photocatalytic activity was also influenced by spatial positions of the substitutions on the porphyrin molecules.     

Porphyrins and metalloporphyrins: potential hypoxic agents

Synthetic water-soluble porphyrins and their metalloporphyrin derivatives with Co(III), Cu(II), Ru(II) and Pt(II), containing various functional groups within the meso-positions of the porphyrin, were synthesised and evaluated as hypoxic agents, especially as cytotoxins and radiosensitisers. Cobalt complexes of the porphyrins containing positively charged methylpyridinium groups showed selective toxicity toward hypoxic Chinese Hamster Ovary (CHO) cells. The Co(III) complexes of the cationic and the anionic porphyrins are all weak radiosensitisers toward hypoxic cells, the highest sensitisation enhancement ratio (SER = 1.22, at 50 muM) being with a porphyrin complex containing a cis-arrangement of two nitro and two methylpyridinium meso-substituents. A copper complex of a tetracationic porphyrin showed slight radiosensitisation activity with an SER value of about 1.1. The other metalloporphyrins showed no hypoxic selectivity or radiosensitisation activity. In total, over 50 porphyrin free bases have been synthesised, of which half are water-soluble and have been metallated; thus, the chemistry is now in place for further development of water-soluble hypoxic agents.     

蒙脱土负载锰卟啉催化氧气对烯烃的环氧化

文章制备了水溶性的四(4-甲基吡啶基)锰卟啉(MnTM4PyP),然后通过浸渍法在水溶液中将锰卟啉负载到蒙脱土上制备了锰卟啉/蒙脱土催化剂(MTM4PyP/MT)。在室温条件下,用此固载型卟啉作为催化剂选择性催化氧气环氧化烯烃到相应的环氧化物。试验结果表明此催化剂可以高活性、高选择性地催化烯烃的环氧化反应,而且可以多次重复使用。     

卟啉类L—B膜分子间相互作用的光谱研究

以无取代的meso-四-(4-N)-吡啶基卟啉及其过渡族金属(主要Cu~(2+)、Zn~(2+))络合物制备L-B膜,以近紫外-可见吸收光谱和荧光光谱为手段,研究叶啉类分子在氯仿溶液中,L-B膜状态下以及固态状态下的相互作用。探讨分子聚集体的存在对光谱性质的影响。 为了研究叶咻类分子间的相互作用及其对光谱性质的影响,我们首先分析了叶啉在CHCl_3溶液中及固态状态下的近紫外-可见吸收光谱和荧光光谱。并将其与叶啉类分子的L-B膜作比较。结果表明,卟啉类的Soret吸收带带宽及峰位置在三种状态下均不相同,L-B膜的情况介于溶液中的和固体下的情况之间,说明了在L-B膜中,卟啉分子存在着某种形式的聚集体,且在这种聚集体中分子间的相互作用程度比固体弱,可以认为L-B膜上的分子呈准晶体状态。     

两亲性卟啉LB膜的Cu~(Ⅱ)离子嵌入作用

研究了带一个脂链三个羟基（ Ｔ Ｈ Ｐ Ｐ１）及三个脂链一个羟基（ Ｔ Ｈ Ｐ Ｐ３）的两种卟啉的单层膜及 Ｌ Ｂ膜的 Ｃｕ２＋ 离子嵌入作用。 Ｃｕ２＋ 嵌入速率和程度取决于膜中卟啉环的取向、分子排列和聚集态。膜中卟啉环较为平躺、排列较疏松、形成 Ｊ 聚体的 Ｔ Ｈ Ｐ Ｐ１ 可快速完全地金属化,而 Ｔ Ｈ Ｐ Ｐ３ 在膜中形成 Ｂ 带劈裂聚集体,环较直立,排列紧密有序, Ｃｕ２＋ 的嵌入缓慢且不完全。     

自组装铁基印迹聚合物的表征及吸附性能研究

采用固相法自组装铁基印迹聚合物（M IP）,并通过XRD与表面滴定手段对其进行表征及研究其吸附性能,结果表明：（1）M IP结晶完好,晶胞系数皆为a=5.036,b=5.036,c=13.749,粒径为28.5 nm;（2）Fe3＋与C6H6O质量比2：1与4：1组装成的微粒表面滴定拟合参数分别为：Nt=7.24×10-5mol.g-1,pKa1=6.77,pKa2=9.62;Nt=7.08×10-5mol.g-1,pKa1=6.62,pKa2=9.59;（3）4：1苯酚模板Fe2O3M IP的吸附性能较优,其投加量为0.5g时吸附效果最好。     

β-取代卟啉及卟啉锰对氧化破坏的稳定性

在假一级条件下,以亚碘酰苯为氧化剂,通过测定β-未取代的四苯基卟啉(TPP),以及不同β-取代的β-Cl8TPP、β-Br8TPP、β-Br4TPP、β-NO2TPP、β-(CH3)8TPP及其金属锰配合物的氧化破坏反应的表观动力学常数,获得了卟啉配体的稳定性顺序为TPP>β-(CH3)8TPP>β-Br8TPP>β-Cl8TPP>β-Br4TPP>β-NO2TPP,β位位阻越大相应的卟啉配体越稳定,并由此推导PhIO由β位进攻卟啉配体。β-取代锰卟啉的稳定性顺序为:Mn(β-Cl8TPP)Cl>Mn(β-Br8TPP)Cl>Mn(β-Br4TPP)Cl>Mn(β-NO2TPP)Cl>Mn(TPP)Cl>Mn[β-(CH3)8TPP]Cl,并与在催化氧化环己烷反应中的稳定性一致,β位吸电子作用越大相应的锰卟啉越稳定,并推导由氧化能力更强的高价金属-氧中间体以位阻较小的面对面方式进攻β-取代锰卟啉。