Palladium Complexes with N,O-Bidentate Ligands Based on N-Oxide Units from Cyclic Secondary Amines:Synthesis and Catalytic Application in Mizoroki-Heck Reaction

Palladium-catalyzed Mizoroki-Heck reaction is a powerful and efficient method for construction of Csp2–Csp2 bonds.Herein,four palladium complexes(I—IV)with N,O-bidentate ligands(L1—L4)based on N-oxide units from cyclic secondary amines were easily synthesized and successfully applied in Mizoroki-Heck reaction of aryl bromides with electron-deficient olefins.X-ray diffraction analyses indicated the palladium(II)atom of II took the distorted square planar geometry and was four-coordinated by nitrogen and oxygen atoms from two ligands(L2).Two free chloride ions were presented as counter anions in complex II.But the palladium(II)center of IV was coordinated by nitrogen and oxygen atoms from one ligand(L4)as well as two chlorine atoms,which exhibited the nearly square-planar geometry.The study on catalytic properties of palladium complexes revealed that complex II exhibited high activity superior to the other complexes.The coupling reactions of a series of aryl bromides and olefin derivatives proceeded in the presence of 2—5 mol%palladium complex II,giving the desired products in good to excellent yields.The advantages of this method such as good compatibility of functional groups,high yields,and short reaction times made it more attractive for constructing Csp2–Csp2 bonds in the synthesis of functional molecules and materials.

Two Cobalt(II) Complexes Derived from the Hydrolysis Product of Di-Schiff Base Ligand N,N'-Bis-(1-benzimidazo-2-yl-ethylidene)-ethane-1,2-diamine:Preparation,Characterization and Crystal Structure of the 6-Coordinate Species [CoL_2]X·H_2O (X = ClO_4^-, N

The reactions of Co（C1O4）2·6H2O and Co（NO3）2.6H2O with the di-Schiff base ligand N,N＇-bis-（1-benzimidazo-2-yl-ethylidene）-ethane-1,2-diamine （LA） in ethanol have been investigated. The reactions of LA with excess amount of cobalt salts yield the six-coordinate complexes [CoL2]（ClO4）E·H2O 1 and [CoL2]（NO3）E·H2O 2 as isolatable products （L= N-（1- benzimidazo-2-yl-ethylidene）-ethane-1,2-diamine）, where L is a tri-dentate mono-Schiff base ligand, resulting from the hydrolysis of the precursor di-Schiff base LA. Both complexes were characterized by X-ray crystallography. Crystal data for complex 1： monoclinic, space group P21/c, a = 11.9214（10）, b = 23.5828（17）, c = 14.0387（12）A, β = 135.219（4）°, C22H30Cl2CoN8O9, Mr = 680.37, V = 2780.1（4） A^3 ,Z = 4, Dc = 1.625 g/cm^3,μ（MoKa） = 0.876 mm^-1, F（000） = 1404, the final R = 0.0725 and wR = 0.1530 for 5726 observed reflections （I 〉 2σ（I））. Crystal data for complex 2： monoclinic, space group P21/c, a = 18.2162（16）, b = 10.0610（6）, c = 18.593（2）A, β = 130.099（3）°, C22H30CoN10O7, Mr = 605.49, V = 2606.5（4） A3 Z = 4, Dc = 1.543 g/cm^3,μ（MoKa） = 0.722 mm^-1, F（000） = 1260, the final R = 0.0619 and wR = 0.1429 for 5194 observed reflections （I 〉 2σ（I））. X-ray diffraction analysis reveals that each cobalt atom in the two complexes is chelated by six nitrogen atoms from two tridentate iigands L, exhibiting a slightly distorted octahedral coordination sphere. In both complexes, the strong hydrogen-bonding interactions between the lattice waters and N-H groups of the ligands result in 1D chains which are further connected by ClO4^- （or NO3^-） groups to form a 3D framework. In complex 2, the strong π-π interactions increase the stability of the structure.

Feasible Synthesis of N,O-Bidentate Difluoroboron Chromophores through Direct Functionalization of Quinoxalin-2(1H)-ones with Ketones in One Shot

Organic difluoroboron complexes are a kind of potential platforms for a wide range of applications owing to their excellent photophysical properties.Herein,we have explored a simple and direct synthesis methodology for a library of N,O-bidentate difluoroboron complexes from quinoxalin-2(1H)-ones and ketones in one shot.The photophysical properties of the generated complexes were evaluated and the application potential of these compounds on subcellular imaging was also explored.

N,O-Bidentated difluoroboron complexes based on pyridine-ester enolates:Facile synthesis,post-complexation modification,optical properties,and applications

An array of pyridine-ester enolate based organoboron complexes has been designed and synthesized via a one-pot cascade of Pd-catalyzedα-arylation and BF2complexation.The rapid structure-activity relationship(SAR)studies indicated that unsymmetrical N,O-chelated BF2complexes were highly fluorescent in solid state,and exhibited large Stokes shifts,excellent photostability,along with insensitivity to p H.Theα-aryl group could not only modulate the electronic effect but also inhibit the intermolecularπ-πstacking to promote the aggregation-induced emission(AIE)effect.DFT calculations and experiments identified that the intramolecular charge transfer properties of these N,O-chelates could be switched by the modification of substituents,resulting tunable fluorescence wavelengths.Furthermore,post-complexation modification was accomplished,including Suzuki-Miyaura cross-coupling,Buchwald-Hartwig amination,oxidative cleavage,along with a unique triple substitution reaction involving propargyl Grignard reagents.The exemplificative application of dimethylamine substituted boron complex as a reversible acidic vapor sensor was also demonstrated.

树枝状大分子N-乙酰半胱氨酸纳米聚合物对视网膜血管重建的作用

目的通过对氧诱导的视网膜病变(OIR)小鼠模型抑制活性氧(ROS)的表达,研究ROS抑制剂纳米试剂树枝状大分子(Dendrimer)和N-乙酰半胱氨酸(NAC)的聚合物(D-NAC)对视网膜血管重建的作用及其机制。方法C57BL/6J小鼠随机分为3组:正常对照组、OIR+Dendrimer组(OIR模型+玻璃体内注射Dendrimer)和OIR+D\|NAC组(OIR模型+玻璃体内注射D-NAC),通过从出生后第7天(P7)到P12暴露在含体积分数75%O 2的环境,从P12到P17返回到含体积分数21%O 2的环境,建立小鼠OIR模型。谷胱甘肽(GSH)检测试剂盒检测各组小鼠视网膜GSH浓度。视网膜荧光染色定量对比两OIR组小鼠间视网膜血管闭塞区(VO)和病理性新生血管(NV)面积,qRT-PCR检测两OIR组小鼠之间视网膜NV相关因子的mRNA水平差异,ELISA法检测两OIR组小鼠之间视网膜血管内皮生长因子(VEGF)蛋白表达的差异,qRT-PCR检测两OIR组小鼠之间视网膜Delta样4配体(DLL4)/Notch通路相关因子的mRNA水平差异。结果GSH检测结果显示,P12、P13、P14、P16、P17时,正常对照组与OIR+Dendrimer组小鼠视网膜GSH水平相比,差异均无统计学意义(均为P>0.05);在P16和P17,与OIR+Dendrimer组相比,OIR+D-NAC组小鼠视网膜GSH水平升高(P<0.05)。视网膜铺片染色结果显示,在P17,与OIR+Dendrimer组相比,OIR+D-NAC组VO及病理性NV面积均减少(均为P<0.05)。qRT-PCR结果显示,在P16,与OIR+Dendrimer组相比,OIR+D-NAC组小鼠视网膜成纤维细胞生长因子、促血管生成素、VEGF、VEGF受体2、促红细胞生成素mRNA水平均降低(均为P<0.05);ELISA检测结果显示,与OIR+Dendrimer组相比,OIR+D-NAC组小鼠视网膜VEGF蛋白表达水平降低(P<0.01)。qRT-PCR检测结果显示,在P16,与OIR+Dendrimer组相比,OIR+D-NAC组小鼠视网膜DLL4/Notch通路相关因子Hey1、NRARP、DLL4、Notch1、Hes1和Hey2 mRNA水平均降低(均为P<0.01)。结论ROS抑制剂D-NAC通过抑制DLL4/Notch信号通路促进OIR的生理性NV形成,抑制病理性NV形成的过程。

卵巢子宫内膜异位囊肿患者血清APRIL与NDRG1的水平表达及其临床价值研究

目的观察血清增殖诱导配体(a proliferation inducing ligand,APRIL),N-myc下游调节基因1(N-myc downstream regulated gene 1,NDRG1)水平变化,并分析其对卵巢子宫内膜异位囊肿(ovarian endometriomas,OEM)的诊断价值。方法选取2021年7月~2022年7月在自贡市第一人民医院就诊的132例OEM患者作为观察组,并进行定期随访,根据患者预后病情有无复发分为复发组(n=50)和未复发组(n=82)。同期在该院体检的健康者78例为对照组。采用酶联免疫吸附法(enzyme linked immunosorbent assay,ELISA)检测血清中APRIL和NDRG1水平;并对复发组和未复发组的一般资料进行比较;采用Logistic回归分析影响OEM预后的相关因素;用Pearson法分析OEM患者血清APRIL与NDRG1表达相关性;绘制受试者工作特征(receiver operating characteristic,ROC)曲线分析血清APRIL和NDRG1对OEM的诊断价值。结果与对照组相比,APRIL水平(35.28±6.81ng/ml vs 26.37±3.19ng/ml)和NDRG1水平(124.39±15.67μg/L vs 9.67±10.82μg/L)升高,差异具有统计学意义(t=10.864,17.278,均P<0.05)。与未复发组比较,复发组血清APRIL(40.38±7.88ng/ml vs 32.16±6.18ng/ml)和NDRG1(132.04±19.83μg/L vs 119.73±13.16μg/L)水平升高,差异具有统计学意义(t=6.668,4.287,均P<0.05)。Logistic回归分析显示,血清APRIL和NDRG1水平是影响OEM患者预后的危险因素(Waldχ^(2)=11.839,28.437,均P<0.001)。Pearson法分析结果显示,OEM患者血清APRIL水平与NDRG1水平呈正相关(r=0.439,P<0.001)。血清APRIL,NDRG1水平联合诊断OEM的曲线下面积(AUC)为0.849,灵敏度和特异度分别为73.95%,85.37%,优于APRIL和NDRG1单独预测(Z=2.644,2.094,P=0.008,0.036)。结论子宫内膜异位囊肿患者血清APRIL和NDRG1水平升高,二者联合对子宫内膜异位囊肿诊断具有较高的临床价值,且与子宫内膜异位囊肿患者的预后密切相关。

新型手性联吡啶叔胺及其衍生的N-氧化物的合成

手性联吡啶配体和叔胺衍生的手性N-氧化物配体的合成是不对称催化领域研究的热点。本文以光学纯的各种取代脯氨酰胺(1)与联吡啶-6-甲醛(2)发生缩合环化反应,合成了8个未见文献报道的手性联吡啶叔胺3a~3h,收率75%~80%,dr>20∶1。化合物3在氧化剂m-CPBA(间氯过氧苯甲酸)的作用下发生氮原子上的氧化反应,合成了8个未见文献报道的手性联吡啶叔胺衍生的N-氧化物4a~4h,总产率45%~51%,dr>20∶1(4e为14/1)。化合物3和4结构经^(1)H NMR,^(13)C NMR和HR-MS(ESI-TOF)表征,化合物3h的绝对构型(3R,7aS)通过单晶X-射线衍射进一步进行了确定。手性联吡啶和手性N-氧化物作为优势配体,其骨架类化合物3和4的合成今后可以为不对称路易斯酸催化提供新配体筛选。

小整联蛋白结合配体N端联结糖蛋白家族在硬组织发育中的调控作用

硬组织发育是生物机体发育过程中的重要组成部分,小整联蛋白结合配体N端联结糖蛋白家族在硬组织发育过程中发挥重要的调控作用,如:促进干细胞的成牙本质分化或成骨分化,调控成牙本质细胞或成骨细胞的基因表达等。编码小整联蛋白结合配体N端联结糖蛋白家族的基因发生突变可引起硬组织矿化异常,导致如低血磷性佝偻病、牙本质发育不全等多种疾病。近年来,学者们对该蛋白家族在硬组织发育中的调控作用开展了深入研究,揭示了该蛋白家族的主要分子调控机制,加深了对其作用及机制的认知。因此,本文对小整联蛋白结合配体N端联结糖蛋白家族在生物硬组织发育中的调控作用及其机制的研究进展进行总结和综述。

Spacial Structure of Cationic Phosphorus Ligand-Ru （Ⅱ） Halide Complexes-by DFT Study

The full-parameter geometry optimization of cationic （ S ） - BINAP - Ru （ Ⅱ ） halide complex was performed by DFT method using B3LYP, PW91 and PBE potentials with several basis sets. PW91 with 3-21G / SDD basis sets is found to be the most suitable method with consideration of both precision and efficiency. The dihedral angles （ θ ） of the binaphthyl or biphenyl with different phosphorus ligand - Ru （ Ⅱ ） halide complexes were found changing from 59.9 to 79.3 degree, while the natural bite angle （ βn ） of those complexes only changes from 87.4 to 90.3 degree. It is different from the common view of asymmetric organic chemists＇ that θ directly influences βn.

Synthesis and Potential Application of Novel C_(2)-Symmetrical Bis(ferrocenyl)P2N Ligand

A novel chiral bis(ferrocenyl) P2N ligand 1 with C2-symmetry was synthesized through a four-step procedure from (R)-N,N-dimethyl-1-ferrocenylethylamine. In a model reaction of Pd-catalyzed allylic alkylation of 1,3-diphenylprop-2-enyl acetate 6 with dimethyl malonate, good enantioselectivity (86% e.e.) was obtained.

Synthesis and Crystal Structure of a New N-alkylated Azacrown Ligand

A new pendant arms macrocyclic ligand, N, N'-bis(2-cyanoethyl)-3,4: 9, 10-dibenzo-1, 12-diaza-5, 8-dioxacyclopentadecane (L), was synthesized in goodyield (93% ) by alkylating 3, 4: 9, 10-dibenzo-1, 12-diaza-5, 8-dioxacyclopentadecane(L') with acrylonitrile. Its crystal structure has been determined by X-ray diffraction.The ligand crystallizes in the orthorhombic system, space group Pbca, a=18. 143 (3),b=11. 206(2), c=22. 274(5)A, V=4528(2)A3, Mr=418. 55, Z= 8, F(000)=1792, Dc= 1. 228 gcm-3, T= 293K, μ= 7. 9 cm-1, final R=0.044 and Rw=0.067(w=1/(σ2 (F) + 0. 0005F2 ) ) based on 2291 independent reflections with F> 4. 0σ(F). The two benzene rings of the macrocyclic ligand are not in the same plane, andthe dihedral angle between them is 73. 6°, the molecule is in a folded state.

Triboluminescent Complexes of Rare Earth Ⅱ.Mixed-ligand Complexes of Eu^(3+) with Thenoyltrifluoroacetone and Pyridine-N-Oxide or its Substitutive Derivatives

Five triboluminescent mixed-ligand complexes of Eu^(3+)with thenoyltrifluoroacetone(TTA)and pyridine-N-oxide or its substitutive derivatives have been prepared.They are all pale yellow crystalline com- pounds with the formula of Eu(TTA)_3·L(L=py NO.2-pie NO,3-pie NO,4-pic NO,bipy N_2O_2).Their physico-chemical properties have been studied with conductometry,UV and IR absorption and fluorescence spectroscopy.Once the complexes are touched or rubbed by a glass rod,they emit strong red triboluminescent light which is similar to the characteristic fluorescence of Eu^(3+).

脯氨酰胺衍生的新型噻吩-叔胺手性N-氧化物的合成

叔胺手性N-氧化物配体的结构多样性合成对金属不对称催化反应具有重要意义。为了拓展手性N-氧化物配体的化学空间,以光学纯的脯氨酰胺或羟脯氨酰胺(1)与各种取代的噻吩-2-甲醛(2)发生缩合环化反应,生成缩合的中间体(3),然后中间体(3)中的氮原子在氧化剂m-CPBA(间氯过氧苯甲酸)的作用下发生N-氧化反应,室温下合成了10个新型噻吩-叔胺手性N-氧化物(4a~4j),总产率41%~57%,dr值为18/1~>20/1,其结构经1H NMR,13C NMR和HR-MS(ESI-TOF)表征。该类手性N-氧化物以L-脯氨酰胺或羟脯氨酰胺作为手性源制备,今后可以为金属不对称催化提供新配体筛选。

Syntheses and Crystal Structures of Two Silver(I) Complexes Isolated by the Reaction of [Ag(PPh_3)_2(MeCN)](SbF_6) with a N_6 Ligand

Two silver(I) complexes were obtained by the reaction of a N6 ligand with [Ag(PPh3)2(MeCN)](SbF6). In complex [AgL1(PPh3)](SbF6) 1, the silver center is bound to three N donors of the nitrogen ligand and P donor of one triphenylphosphine group, forming an irregular AgN3P tetrahedron. In complex [Ag(PPh3)4](SbF6) 2, the Ag+ ion is coordinated to four triphenyl- phosphine groups, affording a tetrahedral geometry. Crystal data for complex 1: C30H37AgF6N6PSb, Mr = 856.25, orthorhombic, space group Pbca, a = 19.0702(9), b = 15.9047(7), c = 21.498(1) ?, V = 6520.5(6) ?3, Z = 8, Dc= 1.744 g/cm3, F(000) = 3408, μ = 1.544 mm-1, the final R = 0.0367 and wR = 0.1077 for 5325 observed reflections with I > 2σ(I); and those for 2: C72H60AgF6P4Sb, Mr = 1392.70, trigonal, space group R3, a = 14.4577(6), b = 14.4577(6), c = 51.544(2) ?, V = 9330.5(7) ?3, Z = 6, Dc= 1.487 g/cm3, F(000) = 4224, μ = 0.913 mm-1, the final R = 0.0352 and wR = 0.1089 for 3498 observed reflections with I > 2σ(I).

Palladium/Imadazolium Salt Mediated Cyclisations for the Synthesis of Heterocyclic Compounds

The use of intramolecular reactions involving palladium/imidazolium salts to synthesize hetero-cyclic compounds is described. Reactivity of phenyl, ethyl and methyl substituents leading to isolation of various isomeric products is also illustrated. Rearrangement of phenyl intermediates to furnish benzoxazoles is also mentioned.

美国白蛾hcapn3基因的克隆及HcAPN3蛋白与Cry1Ac结合特性分析

通过比对分析已知昆虫氨肽酶N(aminopeptidase N,APN)氨基酸序列并结合本实验室的美国白蛾(Hyphantria cunea)中肠iTRAQ结果,设计了hcapn3基因特异引物,获得hcapn3基因片段。通过RACE-PCR技术获得美国白蛾中肠氨肽酶N基因(hcapn3)全长序列(GenBank登录号为KJ013598)。Blastp分析表明,获得的氨肽酶属于氨肽酶N3家族,命名为HcAPN3。序列分析显示HcAPN3包括952个氨基酸残基,具有典型的谷氨酸锌化氨肽酶(Gluzincin)结构域和羧基端(ERAP1_C)结构域。利用Bac to Bac表达系统在昆虫细胞中表达108kDa的HcAPN3蛋白。在原核表达系统中表达58kDa的Gluzincin结构域和49kDa ERAP1_C的结构域蛋白。Ligand Blot分析结果显示,HcAPN3蛋白及Gluzincin结构域可与Cry1Ac蛋白特异性结合,但ERAP1_C结构域未能与Cry1Ac结合。本研究首次克隆了美国白蛾氨肽酶基因并分析了HcAPN3与Cry1Ac的结合特性,为下一步功能研究提供基础。

Synthesis, Characterization, and Evaluation of Antitumor Potential in MCF-7 Cells of Ruthenium-Derived Compounds

To synthesize, characterize and evaluate the antitumor potential derived from ruthenium compounds was generated in this study, from the precursor K[RuCl4(bipy)] a route in a simple and reproducible synthesis for a novel compound of coordinating Ru+3 with bipy and L-trip. The spectroscopic characterization in the middle infrared region (FTIR) shows the interactions between Ru-(L-trip), evidenced by the displacement of the carboxylate ion band for higher energies, and also by the displacements of aliphatic amine bands, suggesting that bidentate coordination of the L-trip ligand occurred. Analysis of the results obtained with thermoanalytical techniques showed that the minimum formula of the compound, [RuCl2(bipy)(L-trip)]1/2H2O. Evaluation of the antitumor potential of precursor K[RuCl4(bipy)] showed the toxic effects on MCF-7 cell line, but did not show selectivity and not reached PBMC cells to the same extent. The evaluation of the antitumor potential of the newly synthesized compound, [RuCl2(bipy)(L-trip)], demonstrated that the insertion of an L-tryptophan molecule into the precursor coordination sphere made it selective when compared to PBMC cells, for MCF-7 type tumor cells.

Two Novel Complexes Based on N-N Bridged Ligand:Syntheses,Crystal Structures,Fluorescence and Magnetic Property

Two novel coordination compounds,1[Zn4（L1）4（NO3）2（H2O）2]（NO3）2·2H2O and 2[Mn2（L2）2（DMF）（H2O）3]（ClO4）2·DMF（HL1 = N＇-[（1E）-pyridine-2-ylmethylidene]pyrazine-2-carbohydrazide,H2L2 = 2-hydroxy-3-methoxybenzaldehyde（pyrazin-2-ylcarbonyl）hydrazone）,based on the N-N bridged ligands were prepared and structurally characterized.Compound 1represents the[2＊2]molecular squares,in which both N atoms belonging to the N-N bridged ligands are connected to the Zn centers.The emission of compound 1 exhibits a blue shift,which can be assigned to strong electrostatic interaction between Zn^Ⅱ ions and the L1^-1.Compound 2represents a rare phenol-O bridged Mn2^Ⅱ complex.The magnetic investigation indicates weak antiferromagnetic interactions between the Mn^Ⅱ centers.

A Novel Dinuclear Copper(Ⅱ)Complex:Synthesis,Crystal Structure,Properties and Hirshfeld Surface Analysis

A novel copper complex [Cu2（L）（DMF）2]（1, H4L =（1 Z,N？Z）-3,5-dibromo-N？-（（3,5-dibromo-2-hydroxyphenyl）（hydroxy）methylene）-2-hydroxybenzohydrazonic acid which was synthesized by in-situ oxidation reaction derived from H2hdb（H2hdb = 6,6′-（（1 E,1？E）-hydrazine-1,2-diylidenebis（methanylylidene）） bis（2,4-dibromophenol）） has been synthesized and characterized by IR, elemental analysis（CHN）, TG and single-crystal X-ray diffraction. The single crystal belongs to monoclinic system, space group P21/c with a = 13.538（1）, b = 3.912（1）, c = 23.778（1）A°, β = 105.232（5）o, Mr = 857.08, V = 1214.9（1） A°^3, Z = 2, Dc = 2.343 g/cm^3, F（000） = 824, μ = 8.375 mm^–1, R = 0.0566, and w R = 0.1610. Compound 1 displays weak anti-ferromagnetic interactions through a η^1：η^1：η^1：η^1：η^1：η^1：μ2-L^4- bridging mode. Hirshfeld surface analysis revealed that complex 1 was supported mainly by Br···H and H···H intermolecular interactions.

基于脯氨酸的新型手性叔胺N-氧化物合成

叔胺衍生的N-氧化物配体的结构多样性合成仍然是不对称催化领域最重要的课题之一。以光学纯的脯氨酰胺或羟脯氨酰胺1与各种取代的吡啶-2-甲醛2发生缩合环化反应,生成中间体3,然后中间体3中的氮原子在氧化剂m-CPBA(间氯过氧苯甲酸)的作用下发生氧化反应,合成了24个新型手性叔胺氮氧化合物4aa~4bk,总产率43%~58%,dr值为10/1~>20/1,其结构经^(1)H NMR,^(13)C NMR和HR-MS(ESI-TOF)表征,化合物4ai的绝对构型(3S,4R,7aS)通过单晶X-射线衍射进行了进一步确定。该类化合物以L-脯氨酸衍生物作为手性源制备了手性N-氧化物,今后可以为金属不对称催化提供新配体筛选。