一种新型Cu(Ⅱ)离子荧光探针的合成及性能研究

以4-N,N-二乙氨基水杨醛为原料,经7-N,N-二乙氨基香豆素-3-甲酸合成了一种新型酰胺类Cu2+荧光探针1。该法具有原料经济易得、合成简单易行的特点。该探针对Cu2+的检测具有良好的离子选择性、抗干扰性能和较高的检测灵敏度,当探针1的浓度为10-5mol/L时,Cu2+的检测限达到2.4×10-7mol/L。该探针与Cu2+以1∶2的摩尔比络合。     

新型香豆素荧光探针的合成及其对三聚氰胺的识别性能研究

合成了一系列基于香豆素的新荧光探针化合物,荧光性质测定表明1,4,7,10-四氮杂环十二烷的香豆素荧光探针对三聚氰胺具有识别作用,检测限为5.0×10-11mol/L.     

核酸荧光探针检测铅离子的研究

将8-17 DNAzym e增加2个"G-C"碱基对进行增强热稳定性的结构修饰,并标记上1个荧光基团"FAM"和2个荧光猝灭基团"Dabcyl",设计成双猝灭Pb2+荧光探针。研究了该探针对Cd2+、Zn2+、Mg2+、Cu2+、Mn2+、Pb2+6种二价金属离子的响应,结果表明探针对Pb2+具有很强的特异性,在探针浓度为2.5×10-7mol/L时,Pb2+浓度在8.5×10-8~7.5×10-6mol/L范围内和探针的荧光强度呈线性关系,检出限为8.5×10-8mol/L。该探针可用于Pb2+的定性和定量检测。     

香豆素-亚胺型Cu~(2+)识别荧光探针的合成及性能

以2,4-二羟基水杨醛为原料经Knoevenagel缩合反应、脱乙酰化反应,再与4-二乙氨基水杨醛经缩合反应,进而通过甲基化合成了新型的香豆素荧光探针.利用核磁共振氢谱(1 H NMR)、碳谱(13 C NMR)和高分辩质谱对所合成的目标化合物进行了结构确认,并测定了其荧光光谱.结果表明,目标化合物对Cu2+有较好的选择性和灵敏度,且当Cu2+浓度在0.66~10μmol·L-1范围内时探针的荧光强度与其浓度有较好的线性关系.Job分析法表明探针与金属离子作用形成1∶1结合的络合物.     

一种罗丹明类Cu~(2+)荧光探针化合物的合成及性能研究

以罗丹明B、水合肼和咔唑为原料,合成了一种新型的荧光增强型Cu2+荧光探针,即4-(N-咔唑基)苯亚甲基罗丹明B腙(CPMRH)。用FTIR、1H NMR和13C NMR对其分子结构进行了表征,并通过荧光光谱对探针的识别性能进行了研究。研究结果表明:探针CPMRH对水溶液中的Cu2+具有良好的选择识别性,且基本不受其他金属离子的影响;探针与Cu2+络合显示粉红色,可以作为一种裸眼检测的试剂用于溶液中Cu2+的检测;当λex=520 nm时,Cu2+水溶液与探针作用可显示橙红色荧光。且Cu2+浓度在1×10-5-5×10-5mol·L-1的范围内,探针的荧光强度与Cu2+浓度呈现出较好的线性关系;Cu2+的最低检出限为5.25×10-7mol·L-1;Job’s曲线表明,探针CPMRH与Cu2+的络合比为1∶1。     

一种新型Cu2+离子荧光探针的合成及性能研究

以4-(二乙氨基)水杨醛为原料,经7-二氨基-3-羧酸香豆素合成了一种新型酰胺类Cu2+荧光探针1。本实验具有合成原料经济易得,合成方法简单易行的特点。并且该探针对Cu2+的检测具有良好的离子选择性,抗干扰性能和较高的检测灵敏度,探针1的浓度为10-5 mol/L时检测限达到2.4×10-7mol/L。同时该探针可以与Cu2+离子1：2的摩尔比络合。     

一种定量测定Pb^2＋的新型荧光探针的合成及性能

以氟化硼络合二吡咯甲川类(BODIPY)染料为荧光团,二(2-羟基乙基)亚胺为识别体合成了一种新的对Pb2+具有高选择性的Pb2+荧光探针.在HEPES缓冲溶液(pH 7.4)中,当Pb2+浓度达到1.0×10-5 mol/L时肉眼可观察到探针荧光强度明显增强;当Pb2+浓度达到3.0×10-4 mol/L时,探针荧光强度增大20倍以上,且识别作用不受其它金属离子(Na+、Mg2+、Ca2+、Cu2+、Fe2+、Hg2+、Ag+、Cd2+、Cr3+、Fe3+)干扰.Pb2+浓度在0.2×10-5～5.0×10-5 mol/L范围内,探针荧光强度与Pb2+浓度有较好的线性关系,相关系数为0.998,检出限为0.2 μmol/L.     

脱氢枞酸基芳胺荧光探针探测金属离子的应用

通过脱氢枞酸基芳胺荧光探针a,b,c对不同金属离子(Ca2+、K+、Mg2+、Mn2+、Na+、Ni2+、Pb2+、Fe3+、Cu2+)的识别性、对其他金属离子的抗干扰性、以及金属离子对探针的荧光滴定试验,研究了它们作为金属离子荧光探针的应用。结果表明,a和b对Fe3+、c对Cu2+具有良好识别性,其识别性能受其他金属离子的干扰性不明显;Fe3+浓度分别在1.0×10-7~6.0×10-6mol·L-1和2.0×10-7~7.0×10-6mol·L-1范围内,a和b的荧光强度与Fe3+浓度有较好的线性关系,Cu2+浓度在6.0×10-6~3.0×10-5mol·L-1范围内,c的荧光强度与Cu2+浓度有较好的线性关系,可以定量检测中性水溶液中Fe3+和Cu2+含量。     

新型罗丹明类Ca2+荧光探针的合成及光谱性能研究

以2-氨基酚和3-(二乙基氨基)苯酚为原料,经过5步反应合成了新型罗丹明类荧光探针化合物,研究发现该化合物对Ca2+具有较高的选择识别性能,并且受常见离子的干扰较小.探针的荧光强度与Ca2+浓度(2×10-6～5×10-5mol/L)呈较好的线性关系.     

含氟香豆素荧光探针的合成及其荧光性能研究

以7-羟基-4-三氟甲基香豆素和1,4,7,10-四氮杂环十二烷(Cyclen)为原料,合成了具有多荧光侧臂的新型香豆素类荧光探针化合物,该合成方法经济简单,且环境友好。关键中间体及目标物经1HNMR、13CNMR和LC-MS分析表征,根据其荧光发射强度的不同讨论了探针化合物在乙腈中的荧光性能。     

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%.     

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.     

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.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.