反式阿魏酸钌配合物的合成、表征、荧光光谱及其与DNA/蛋白作用

对天然产物反式阿魏酸进行化学修饰,设计、合成了2种单核钌配合物[Ru(cym)(L)Cl]Cl (Ru-1)与[Ru(bpy)2(L)]Cl2(Ru-2)(cym=对伞花烃,bpy=2,2′-联吡啶,L=(E)-3-(4-hydroxy-3-methoxyphenyl)-N-((4′-methyl-(2,2′-bipyridin)-4-yl)methyl)acrylamide),通过核磁共振氢谱和碳谱、电喷雾质谱对配合物进行了结构表征。利用荧光、紫外-可见光谱等方法研究了配合物的溶解性和光学性质。配合物均具有良好的亲水性。Ru-2有良好的荧光性能,其发射波长达到近红外的631 nm,且可以在pH值为8～10之间实现响应。Ru-2还具有较高的单线态氧量子产率(Φ=0.70),有望成为一类高效的光敏剂。2种配合物都与CT-DNA发生嵌入作用(Kb分别为1.210×104和1.233×103L·mol-1);均与BSA有一个结合位点,使其荧光发生静态淬灭(Ka值分别为1.94×104,2.45×104)。     

Ru(Ⅱ)和Ru(Ⅲ)配合物[Ru(bpy)(PH3)(-C≡CC6H4NO2-p)Cl]m(m=0,+1)的光谱性质的密度泛函-含时密度泛函理论研究

我们利用DFT中的B3LYP方法优化了Ru(Ⅱ)配合物和氧化的Ru(Ⅲ)配合物[Ru(bpy)(PH3)(-C≡CC6H4NO2-p)Cl]m[bpy=2,2′-bipyridine;m=0(1), 1(1 )]的基态几何结构,得到的几何参数与实验结果吻合的很好。采用TDDFT方法,得到了配合物1和1 的激发态电子结构和电子吸收光谱。研究结果表明,配合物1和1 随着氧化过程的发生,光谱性质也发生变化,Ru(Ⅱ)配合物的低能吸收被指认为MLCT/LLCT混合跃迁,而氧化的Ru(Ⅲ)配合物1 的低能吸收具有LMCT跃迁性质。     

含1,3,4-噁二唑的联吡啶钌(Ⅱ)配合物的合成及光电性质研究(英文)

合成了2个新的含1,3,4-噁二唑官能团的联吡啶配体及其相应的钌髤配合物Ru(CPOD)(dcbpy)(NCS)2(Ru-1)和Ru(DPOD)(dcbpy)(NCS)2(Ru-2)(CPOD=4-羧基-4′-[2-(4-壬氧基苯基)-5-苯基-1,3,4-噁二唑]-2,2′-二联吡啶,DPOD=4,4′-二[2-(4-壬氧基苯基)-5-苯基-1,3,4-噁二唑]-2,2′-二联吡啶,dcbpy=4,4′-二羧基-2,2′-二联吡啶),并通过红外光谱、循环伏安、紫外可见吸收光谱、元素分析和光电流-光电压曲线实验对其结构和光电转化性质进行了表征。这些配合物的最大MLCT态吸收位于555nm,摩尔消光系数可达1.43×104L·mol-1·cm-1。它们的光化学和电化学性质表明:激发态能级与TiO2导带底能级匹配,电子能够注入到TiO2导带中。将它们敏化到纳米晶TiO2电极上,光电转化效率为2.4%。     

含2,6-二(甲基苯并咪唑)吡啶钴、镨配合物的合成、结构、电化学性质和理论计算研究

以2,6-二(甲基苯并咪唑)吡啶和2,2′-联吡啶为配体,合成了一个钴的配合物[Co(mbzimpy)(bipy)Cl]Cl O4·1.3H2O(1)和一个镨的配合物[Pr(mbzimpy)2(NO3)2]Cl O4·2CH3COCH3(2),(mbzimpy=2,6-bis(methylbenzimidazol-2-yl)pyridine,bipy=2,2′-bipyridine)并利用单晶衍射对其结构进行了表征。还对配合物1和2的荧光和电化学性质进行了研究。晶体结构中C-H…O氢键和π-π芳环堆积作用将每个单核分子连接成一个三维的空间结构。配合物1的TD-DFT理论计算的结果表明:实验得到的紫外谱图和理论计算的紫外谱图较好地吻合。通过循环伏安图可以了解金属中心的氧化和还原电子对。在不同偶极矩的溶剂中研究其荧光性能。     

基于3,5-二硝基苯甲酸和2,2′-联吡啶的Cu(Ⅱ)、Zn(Ⅱ)配合物的合成及晶体结构

以3,5-二硝基苯甲酸(3,5-Hdnbc)和2,2′-联吡啶(2,2′-bipy)为配体,与Zn2+和Cu2+反应,得到了4个配合物[Zn(3,5-dnbc)2(2,2′-bipy)(H2O)]·(3,5-Hdnbc)(1),[Cu(3,5-dnbc)2(2,2′-bipy)(H2O)](2),[Cu(2,2′-bipy)2(3,5-dnbc)](NO3)·2(3,5-Hdnbc)(3),和[Cu(2,2′-bipy)2Cl](3,5-dnbc)·(3,5-Hdnbc)(4)。用元素分析、红外光谱对其进行了表征,并用单晶X-射线衍射测定了配合物的晶体结构;对配合物1和2进行了热重分析。4个配合物均为单核分子。配合物1中,Zn2+离子是五配位的三角双锥结构;配合物2中,Cu2+离子是五配位的变形四方锥结构;配合物3和4中,Cu2+离子均是五配位的三角双锥结构;配合物中存在氢键和π-π堆积等弱的分子间作用力。     

含2,6-二(甲基苯并咪唑)吡啶钴、镨配合物的合成、结构、电化学性质和理论计算研究（英文）

以2,6-二(甲基苯并咪唑)吡啶和2,2′-联吡啶为配体,合成了一个钴的配合物[Co(mbzimpy)(bipy)Cl]Cl O4·1.3H2O(1)和一个镨的配合物[Pr(mbzimpy)2(NO3)2]Cl O4·2CH3COCH3(2),(mbzimpy=2,6-bis(methylbenzimidazol-2-yl)pyridine,bipy=2,2′-bipyridine)并利用单晶衍射对其结构进行了表征。还对配合物1和2的荧光和电化学性质进行了研究。晶体结构中C-H…O氢键和π-π芳环堆积作用将每个单核分子连接成一个三维的空间结构。配合物1的TD-DFT理论计算的结果表明:实验得到的紫外谱图和理论计算的紫外谱图较好地吻合。通过循环伏安图可以了解金属中心的氧化和还原电子对。在不同偶极矩的溶剂中研究其荧光性能。     

一个对2,4,6-三硝基苯酚和Fe~(3+)离子具有双重荧光传感行为的层状镉(Ⅱ)-有机配位聚合物（英文）

通过水热法合成了一个由三连接的2,3-喹啉二甲酸桥联扭曲的Cd~(2+)八面体形成的二维层状配位聚合物[Cd(QDA)]_n(1)。该配合物发射出较强的蓝色荧光并具有很高的热稳定性和化学稳定性。更为重要的是,该配合物在乙醇分散体系中可快速识别痕量的2,4,6-三硝基苯酚和Fe~(3+)离子,其对2,4,6-三硝基苯酚的淬灭常数(K_(sv))和检测限(LOD)分别为6.61×10~4L·mol~(-1)和0.83μmol·L~(-1),对Fe~(3+)离子的淬灭常数和检测限分别为1.74×10~4L·mol~(-1)和2.70μmol·L~(-1)。     

两个线形三核配合物的晶体结构及性质

合成并表征了2个新的线性三核配合物[Co_2~ⅢCo~ⅡL_2(μ-OAc)_4](1)和[Ni_3L_2(μ-OAc)_2(CH_3OH)_2]·2H_2O(2),其配体L为2-羟基-1,3-丙二胺和5-氟水杨醛缩合的产物。配合物1与DNA的作用通过紫外-可见光谱、荧光光谱、粘度实验和电化学方法进行了研究。紫外-可见光谱的结果表明配合物1与DNA的结合常数为2.43×10~(5 )L·mol~(-1)。荧光光谱的研究结果表明配合物1能取代溴化乙锭和DNA结合,其淬灭常数为4.92×10~(3 )L·mol~(-1)。配合物1和2的变温磁学性质研究表明在2个配合物的三金属中心之间均存在反铁磁性耦合。     

4-氯-2-(1H-咪唑并[4,5-f][1,10]菲咯啉)苯酚铜(Ⅱ)配合物的晶体结构及其与DNA的相互作用

利用菲咯啉酮衍生物4-氯-2-(1H-咪唑并[4,5-f][1,10]菲咯啉)苯酚(HL)设计合成了一种新的单核铜配合物[Cu(L)(5-Cl-sal)(DMF)]ClO_4·DMF(5-Cl-Hsal=5-氯-水杨醛),用元素分析和X射线单晶衍射等手段对配合物进行了表征。该配合物晶体属三斜晶系,P1空间群。用紫外吸收光谱、荧光光谱和凝胶电泳等方法研究了配合物与DNA的相互作用。结果表明,配合物以插入方式与CT-DNA结合,结合常数为1.02×10~3 L·mol~(-1)。同时配合物也能较大程度淬灭EB-DNA复合物的荧光,表观键合常数为4.37×10~5L·mol_(-1),略小于经典键合常数107 L·mol~(-1)。淬灭机理为动态淬灭。凝胶电泳实验研究表明配合物在H_2O_2存在下可将pBR322质粒DNA切割为开环缺口型DNA和线型DNA,配合物浓度越大,切割效果越好。机理研究显示,配合物切割DNA的反应是由羟基自由基(·OH)和单线态氧(~1O_2)作为活性物种的氧化切割过程。     

配合物[Ru(tpa)(H_2biim)](ClO_4)_2和[Ru(tpa)(H_2bbim)](ClO_4)_2的合成、晶体结构及紫外光谱理论研究

以三(2-吡啶甲基)胺(tpa)为螯合配体合成了2种新型的钌配合物[Ru(tpa)(H_2biim)]·(ClO_4)_2(1)和[Ru(tpa)(H_2bbim)]·(ClO_4)_2(2)(H_2biim=2,2′-联咪唑;H2bbim=2,2′-苯并联咪唑),并研究了它们的晶体结构和紫外光谱.通过理论计算对紫外光谱峰值进行了指认,光谱模拟和实验吻合.计算发现2种配合物分子的最低空轨道落在H_2biim或H_2bbim配体上,和其他Ru-H_2biim(H_2bbim)配合物有所不同.     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.     

A general and convenient synthesis of 4-(tosylmethyl)semicarbazones and their use in amidoalkylation of hydrogen,heteroatom, and carbon nucleophiles

A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.     

Synthesis of novel chiral bidentate hydroxyalkyl-N-heterocyclic carbene ligands and their application in palladium-catalyzed Mizoroki–Heck couplings and asymmetric addition of diethylzinc to benzaldehyde

A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

Microwave-assisted copper-catalyzed stereoselective ring expansion of three-membered heterocycles with α-diazo-β-dicarbonyl compounds

Microwave-assisted copper-catalyzed ring expansions of three-membered heterocycles with α-diazo-β-dicarbonyl compounds were investigated. Thiiranes generated 3-acyl-5,6-dihydro-1,4-oxathiines in the presence of copper sulfate and trans-3-acyl-5,6-dihydro-1,4-oxathiines as stereospecific products for 1,2-disubstituted cis-thiiranes through an intramolecular S_N2 process. Oxiranes gave rise to 2-acyl-5,6-dihydro-1,4-dioxines under the catalysis of copper hexafluoroacetylacetonate and cis-3-acyl-5,6-dihydro-1,4-dioxines as stereospecific products for 1,2-disubstituted cis-oxiranes via an intimate ion-pair mechanism. The current method provides a direct and simple strategy in efficient preparation of 3-acyl-5,6-dihydro-1,4-oxathiines and 2-acyl-5,6-dihydro-1,4-dioxines, important agents in medicinal and agricultural chemistry, from readily available thiiranes and oxiranes, respectively.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.