生物素标记试剂的合成方法改进及其在DNA合成中的应用

以生物素,4,4’-二甲氧基三苯基氯甲烷,6-氨基-1-己醇,2-氰基乙氧基-双(N,N-二异丙基)亚磷酰胺等为原料,采用改进方法合成了生物素标记试剂——[1-N-(4,4’-二甲氧基三苯甲基)-生物素-6-氨基己基]-2-氰乙氧基-N,N-二异丙基亚磷酰胺(3),总收率51.0%,其结构经1H NMR,13C NMR,31P NMR和MS确证。通过固相亚磷酰胺三酯法,应用3合成了一段含有十个碱基的5’-端生物素标记的寡核苷酸链,其结构经MS确证。     

含三苯基氧膦基团的磺化聚苯并咪唑质子交换膜

通过酯化反应合成了3,3'-二磺酸钠-4,4'-二甲酸二甲酯基联苯和二(4-甲酸甲酯基苯基)苯基氧膦单体,并将其与3,3'-二氨基联苯胺共缩聚,制备了含三苯基氧膦基团的可溶性磺化聚苯并咪唑.三苯基氧膦基中的苯侧基促使高分子链排列疏松,产物溶解性提高;而氧膦基团增加了产物的吸水率,并显著提高了其电导率.     

对位氨基能显著提高D-A-D型化合物的双光子吸收性能

报道了具有典型D-A-D型共轭结构的反式2,5-二氰基-1,4-二(4'-甲氧基苯乙烯基)苯(MOS-CN), 2,5-二氰基-1,4-二(4'-二甲胺基苯乙烯基)苯(MAS-CN)和1,4-二(4'-甲氧基苯乙烯基)苯(MOS)的合成. 用核磁、红外和元素分析进行了表征. 测试了紫外吸收光谱、单光子荧光光谱、双光子荧光光谱、双光子吸收系数及双光子吸收截面. 在800 nm的飞秒脉冲激光激发下, 化合物MOS-CN, MAS-CN和MOS分别发出很强的绿色、黄色和蓝色上转换荧光. 化合物MOS-CN, MAS-CN和MOS的最大吸收波长、单光子发射波长、双光子诱导荧光波长、荧光量子产率、双光子吸收系数、双光子吸收截面及双光子荧光寿命各分别是393, 473, 367 nm; 470, 569, 434 nm; 475, 574, 438 nm; 0.12, 0.72, 0.21; 0.8, 5.3, 0.3 cm/GW; 270, 1790, 101 GM; 140 ps, 1.32 ns, 54 ps. MAS-CN的双光子吸收截面是MOS-CN的6.63倍, MOS-CN的双光子吸收截面是MOS的2.67倍, 表明对位氨基显著地提高了化合物的双光子吸收性能, 氰基也较大地提高了双光子吸收截面.     

4,4'-二(对氨基苯乙炔基)-6,6'-二[N,N-二(乙氧基羰甲基)氨甲基]-2,2'-联吡啶的合成与表征

以4,4'-二硝基-2,2'-联吡啶-6,6'-二亚甲基双三氟乙酸酯作为起始原料, 经水解、 溴化、 酯化和对氨基苯乙炔取代4步反应合成了4,4'-二(对氨基苯乙炔基)-6,6'-二[N,N-二(乙氧基羰甲基)氨甲基]-2,2'-联吡啶. 通过红外光谱、 核磁共振波谱、 高分辨质谱等表征了该化合物的结构. 该化合物经水解后与铕离子形成稀土荧光螯合物, 在紫外光激发下, 发射出具有铕离子特征的荧光光谱.     

Synthesis and Characterization of 4,4'-Di (p-aminophenylethynyl)-6,6'-bis[ N,N-bis(ethoxycarbonylmethyi) amino methyl ]-2,2'-bipyridine

以4,4'-二硝基-2,2'-联吡啶-6,6'-二亚甲基双三氟乙酸酯作为起始原料,经水解、溴化、酯化和对氨基苯乙炔取代4步反应合成了4,4'-二.(对氨基苯乙炔基)-6,6'-二[N,N-二(乙氧基羰甲基)氨甲基]-2,2'-联吡啶.通过红外光谱、核磁共振波谱、高分辨质谱等表征了该化合物的结构.该化合物经水解后与铕离子形成稀土荧光螯合物,在紫外光激发下,发射出具有铕离子特征的荧光光谱.     

4,4''''-二甲氧基-5,6,5'''',6''''-二次甲二氧基-2-烷氧甲酰基-2''''-(4-取代苄基哌嗪基-1)-甲酰基联苯的合成

在NiCl2(PPh3)2/NaH/Zn/PPh3作用下,以2-溴-3,4-次甲二氧基-5-甲氧基-苯甲酸甲酯为原料进行Ullmann-type偶合,在温和条件下以较高的收率得到中间体4,4'-二甲氧基-5,6,5',6'-二次甲二氧基联苯-2,2'-二甲酸二甲酯,经进一步的水解、环化成酸酐、开环酯化等反应得到4,4'-二甲氧基-5,6,5',6'-二次甲二氧基联苯-2,2'-二甲酸单酯.最后再与取代苄基哌嗪在DMAP及DCC催化下缩合,得到12个新的不对称联苯甲酸酯甲酰哌嗪类化合物,并用1H NMR,IR,ESI-MS等手段进行了结构确认.     

狼毒乙素分子印迹膜荧光传感器的制备及在中药材检测中的应用

以狼毒大戟根部提取的狼毒乙素(ECB)为模板分子, 7-二乙氨基香豆素-3-羧酸与3-溴丙烯缩合生成的烯丙端基香豆素类化合物(DCAC)为荧光单体, 丙烯酰胺为功能单体, 乙二醇二甲基丙烯酸酯为交联剂, 偶氮二异丁腈为引发剂, 通过自由基聚合制备了具有强烈青色荧光, 并且可以选择性富集狼毒乙素的分子印迹膜荧光传感器(FL-MIF). 研究结果表明, FL-MIF吸附ECB的线性范围为1.00~50.00 μmol/L, 在线性范围内, 随着ECB浓度递增, 青色荧光(489 nm)呈现出明显的荧光猝灭响应, 狼毒乙素的检测限为0.29 μmol/L. FL-MIF对ECB具有良好的特异选择性识别性能, 印迹因子为3.58, 明显高于类似结构的2-甲氧基-4-羟基苯甲酸(MHBA)、 没食子酸(GA)和3,3'-二乙酰基-4,4'-二甲氧基-2,2',6,6'-四羟基二苯基甲烷(DDTPM). 重复再生性能优异的FL-MIF可应用于实际样品中药材狼毒大戟ECB含量的检测.     

异硫氰酸荧光素-溶菌酶的制备及晶体生长预研究

迄今尚未有适用于光源为488 nm激光扫描共聚焦显微镜研究用的溶菌酶. 为此, 用异硫氰酸荧光素作为探针标记了溶菌酶, 测定了溶菌酶标记物的紫外-可见吸收光谱和荧光光谱, 摸索了其晶体的生长条件. 实验结果表明, 在标记过程中异硫氰酸荧光素没有影响溶菌酶的生化性质, 标记后的溶菌酶可用于激光扫描共聚焦显微镜进行后续研究.     

固相研磨合成4,4''''-联吡啶季铵盐

采用室温固相研磨的方法,4,4'-联吡啶与连有阻塞基的乙氧乙醇磺酸酯(或苄溴)反应,得到单取代的4,4'-联吡啶六氟磷酸盐(2),2再与α,α'-二(溴甲基)-2,2'-联吡啶反应,得到哑铃型化合物--2,2'-联吡啶桥连的双-4,4'-联吡啶六氟磷酸盐(3),收率约90%.2和3的结构经1H NMR, 13C NMR和MS表征.     

天然产物Combretastatin A-1和Combretastatin B-1的合成

基于Perkin反应策略合成了具有强效抗肿瘤、抗血管活性的天然产物Combretastatin A-1(CA1)和Combretastatin B-1(CB1).以2,3,4-三羟基苯甲醛(1)为起始物, 经单甲基化反应得到2,3-二羟基-4-甲氧基苯甲醛(2), 再经酚羟基保护得到2,3-二异丙基-4-甲氧基苯甲醛(3), 该化合物与3,4,5-三甲氧基苯乙酸(4)发生Perkin反应分离得到E-2-(3,4,5-三甲氧基苯基)-3-(2',3'-二异丙氧基-4'-甲氧基)丙烯酸(E-5), 经脱羧反应得到Z-3,4,4',5-四甲氧基-2',3'-二异丙氧基二苯乙烯(6), 最后经脱保护反应得到CA1.另外, 将E-2-(3,4,5-三甲氧基苯基)-3-(2',3'-二异丙氧基-4'-甲氧基)丙烯酸(E-5)脱去保护基得到E-2-(3,4,5-三甲氧基苯基)-3-(2',3'-二羟基-4'-甲氧基)丙烯酸(7), 该化合物经脱羧-异构化反应得到E-3,4,4',5-四甲氧基-2',3'-二羟基二苯乙烯(E-CA1), 最后经催化氢化得到CB1.     

Synthesis,characterization and thermooxidative stability of addition polymers from 1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracene and anthracene end-capped imide oligomers

A series of Diels–Alder addition-type copolymers prepared from 1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracence and anthracene end-capped 6F-PDA imide oligomers were characterized. The composition of the anthracene end-capped imide oligomers was found to be sensitive to monomer molar ratios and the mode of monomer addition. The resistance of the copolymer to thermooxidative degradation at 316 and 371°C was compared with a similar commercial polymer called Avimid-N prepared from 4,4′-hexafluoroisopropylidene-2,2′ bis(phthalic acid anhydride) and para-and meta-phenylene diamine, abbreviated 6F-PDA. There are strong indications that the copolymers undergo degradation initially by unzipping the diepoxyanthracene unit from the anthracene end-capped 6F-PDA oligomer unit (Avimid-N like repeat unit), followed by a slower degradation of the more stable residual 6F-PDA unit. © 1993 John Wiley & Sons, Inc.     

Regulation of π-stacked anthracene arrangement for fluorescence modulation of organic solid from monomer to excited oligomer emission

The construction and precise control of the face-to-face π-stacked arrangements of anthracene fluorophores in the crystalline state led to a remarkable red shift in the fluorescence spectrum due to unprecedented excited oligomer formation. The arrangements were regulated by using organic salts including anthracene-1,5-disulfonic acid (1,5-ADS) and a variety of aliphatic amines. Because of the smaller number of hydrogen atoms at the edge positions and the steric effect of the sulfonate groups, 1,5-ADS should prefer face-to-face π-stacked arrangements over the usual edge-to-face herringbone arrangement. Indeed, as the alkyl substituents were lengthened, the organic salts altered their anthracene arrangement to give two-dimensional (2D) edge-to-face and end-to-face herringbone arrangements, one-dimensional (1D) face-to-face zigzag and slipped stacking arrangements, a lateral 1D face-to-face arrangement like part of a brick wall, and a discrete monomer arrangement. The monomer arrangement behaved as a dilute solution even in the close-packed solid state to emit deep blue light. The 1D face-to-face zigzag and slipped stacking of the anthracene fluorophores caused a red shift of 30-40?nm in the fluorescence emission with respect to the discrete arrangement, probably owing to ground-state associations. On the other hand, the 2D end-to-face stacking induced a larger red shift of 60?nm, which is attributed to the excimer fluorescence. Surprisingly, the brick-like lateral face-to-face arrangement afforded a remarkable red shift of 150?nm to give yellow fluorescence. This anomalous red shift is probably due to excited oligomer formation in such a lateral 1D arrangement according to the long fluorescence lifetime and little shift in the excitation spectrum. The regulation of the π-stacked arrangement of anthracene fluorophores enabled the wide modulation of the fluorescence and a detailed investigation of the relationships between the photophysical properties and the arrangements.     

Regulation of π‐Stacked Anthracene Arrangement for Fluorescence Modulation of Organic Solid from Monomer to Excited Oligomer Emission

The construction and precise control of the face‐to‐face π‐stacked arrangements of anthracene fluorophores in the crystalline state led to a remarkable red shift in the fluorescence spectrum due to unprecedented excited oligomer formation. The arrangements were regulated by using organic salts including anthracene‐1,5‐disulfonic acid (1,5‐ADS) and a variety of aliphatic amines. Because of the smaller number of hydrogen atoms at the edge positions and the steric effect of the sulfonate groups, 1,5‐ADS should prefer face‐to‐face π‐stacked arrangements over the usual edge‐to‐face herringbone arrangement. Indeed, as the alkyl substituents were lengthened, the organic salts altered their anthracene arrangement to give two‐dimensional (2D) edge‐to‐face and end‐to‐face herringbone arrangements, one‐dimensional (1D) face‐to‐face zigzag and slipped stacking arrangements, a lateral 1D face‐to‐face arrangement like part of a brick wall, and a discrete monomer arrangement. The monomer arrangement behaved as a dilute solution even in the close‐packed solid state to emit deep blue light. The 1D face‐to‐face zigzag and slipped stacking of the anthracene fluorophores caused a red shift of 30–40 nm in the fluorescence emission with respect to the discrete arrangement, probably owing to ground‐state associations. On the other hand, the 2D end‐to‐face stacking induced a larger red shift of 60 nm, which is attributed to the excimer fluorescence. Surprisingly, the brick‐like lateral face‐to‐face arrangement afforded a remarkable red shift of 150 nm to give yellow fluorescence. This anomalous red shift is probably due to excited oligomer formation in such a lateral 1D arrangement according to the long fluorescence lifetime and little shift in the excitation spectrum. The regulation of the π‐stacked arrangement of anthracene fluorophores enabled the wide modulation of the fluorescence and a detailed investigation of the relationships between the photophysical properties and the arrangements.     

Unequivocal synthesis of bis(2-cyanoacrylate) monomers. I. Via anthracene adducts

An unequivocal and general synthesis of bis(2-cyanoacrylate) monomers from Diels-Alder adducts of the alkyl 2-cyanoacrylates has been developed. Saponification of the anthracene adduct of either isobutyl or ethyl 2-cyanoacrylate to the anthracene/2-cyanoacrylic acid adduct, conversion of the latter to the alkali salt or acid chloride derivatives, followed by respective esterification reactions with an organic dihalide or glycol gave the bis-anthracene adduct precursors to the bis(2-cyanoacrylate) monomers. Heating the bis-adducts with excess maleic anhydride in refluxing xylene effected retrograde diene scission to the bis(2-cyanoacrylate) monomers in up to 80% overall yields. Comonomer blends of the difunctional bis(2-cyanoacrylates) with the alkyl 2-cyanoacrylates gave crosslinked polymeric adhesive compositions exhibiting higher bond strengths under both dry and wet conditions than the noncrosslinked cyanoacrylate adhesives. Potential applications of interest are as pit and fissure sealants in dentistry and for the direct bonding of orthodontic attachments.     

Copolymerization of Chloroprene with Methyl Methacrylate by the EtnAICI3.n (n=1, 1.5, 2)-Vanadium Compound System

Abstract

The copolymerization of chloroprene with methyl methacrylate was studied in the presence of Et_n A1C1_3-n (n=1, 1.5, 2)-vanadium compounds. Monomer reactivity ratios in various catalyst concentrations were compared with that of a usual radical initiator. The apparent monomer reactivity ratio changed with the concentration of alkylaluminum halide. In this polymerization, alternating copolymer could not be prepared by the ordinary catalyst concentration by which the alternating copolymerization of chloroprene with acrylonitrile was carried out. The addition of more than 10 mole % of the alkylaluminum halide based on two monomers was required to prepare the copolymer which had equimolar composition irrespective of the feed monomer ratio.

The configuration in the repeating unit of the copolymer was discussed by comparison with the NMR and IR spectra of the radical copolymer and the cyclic Diels-Alder adduct of chloroprene-methyl methacrylate. The high alternating tendency was clarified by ozonolysis of the copolymer which was prepared under the conditions which produced equimolar copolymer in various feed monomer ratios. The chloroprene unit of the copolymer was present in the 1, 4-trans structure in the copolymer prepared by the Et_n A1C1_3-n -vanadium compound system.     

一种含三苯胺链段的PPV类交替共聚物的合成、表征及性能

合成了三苯胺二醛和1-甲氧基-4-辛氧基-2,5-二甲苯双(三苯基氯化)两种单体,通过Wittig反应制得了共轭聚合物,对共轭聚合物进行了表征和性能测试.这类共轭聚合物的氯仿溶液和膜在紫外光激发下能发出强的蓝绿光,与小分子三苯胺衍生物(TPD)相比,具有相对较高的热稳定性和良好的成膜性.电化学分析表明聚合物具有很好的空穴传输能力.同时对共轭聚合物的光致发光和电致发光性能进行了研究,结果表明,此聚合物与同类聚对亚苯基亚乙烯基(PPV)型聚合物相比具有较低的驱动电压和较高的发光亮度,是一种潜在的有机高分子电致发光材料.     

2-甲基-8-羟基喹啉-丙烯酸-镓(Ⅲ)与甲基丙烯酸甲酯共聚物的合成与表征

制备了 2 甲基 8 羟基喹啉、丙烯酸与镓 (Ⅲ )的三元配合物 ,将此配合物与甲基丙烯酸甲酯共聚后得到含镓 (Ⅲ )的共聚物 ,这种共聚物易溶于氯仿、丙酮等普通低沸点溶剂 ,具有良好的成膜性能 .用红外光谱、元素分析、紫外光谱等方法对三元配合物和共聚物的组成进行了表征 .测试三元配合物和共聚物的荧光光谱 ,表明共聚物在 4 96nm处能发出较强的荧光 .DSC和TG分析表明 ,共聚物具有良好的耐热性和热稳定性 .     

Pulse radiolysis of 4,4'-bipyridyl aqueous solutions at elevated temperatures: spectral changes and reaction kinetics up to 400 degrees C

The spectral changes as well as the reaction kinetics of the transient species of 4,4'-bipyridyl (4,4'-bpy) have been experimentally investigated by pulse radiolysis techniques up to 400 degrees C. The results show that the transient species such as OH adduct 4,4'-bpyOH*, monoprotonated electron adduct 4,4'-bpyH*, and doubly protonated electron adduct 4,4'-bpyH2+* have 15-20 nm blue shifts from room temperature to 400 degrees C. For a deaerated neutral solution of 4,4'-bpy in the presence of tert-butyl alcohol, ethanol, or NaCOOH, the doubly protonated electron adduct is the main transient species at room temperature. But at temperatures > 350 degrees C, a monoprotonated form, the N-hydro radical 4,4'-bpyH*, becomes predominant. Interestingly, at room temperature, CO2-* could not efficiently react with 4,4'-bpy, but the reaction was accelerated with increasing temperature; at 350 degrees C, this reaction completed within 2 mus. Using an alkaline solution (pH = 11.5) of 4,4'-bpy in the presence of tert-butyl alcohol, we studied the N-hydro radical 4,4'-bpyH* from room temperature to 400 degrees C at 25 MPa. An estimation of the temperature-dependent G(e(aq)-) at 25 MPa agrees with our previous result with methyl viologen as a scavenger.     

Novel poly(fluorinated imide)s containing naphthalene pendant group: synthesis and characterization

A new fluorinated diamine monomer containing naphthalene pendant group, bis(4-amino-3,5-difluorophenyl)naphthylmethane (monomer 1), was synthesized from 1-naphthaldehyde and 2,6-difluoroaniline with trifluoromethanesulfonic acid at reflux. The novel poly(fluorinated imide)s (PFIs) were prepared via one-step polycondensation by monomer 1 and three aromatic dianhydrides including 4,4′-oxydiphthalic dianhydride, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride, and 3,3′,4,4′-biphenyltetracarboxylic dianhydride in m-cresol, respectively. The obtained PFIs could be dissolved in a variety of organic solvents such as N-methyl-2-pyrrolidinone, N,N-dimetahylacetamide (DMAC), N,N-dimethylformamide, chloroform, and tetrahydrofuran at room temperature. The highest solubility of PFIs could even reach to 250 mg/mL in chloroform. The PFIs could be easily processed into flexible and tough films by casting onto glass from DMAC solution. The PFI films had a tensile strength, elongation at break, and tensile modulus in the range of 84–102 MPa, 8.7–12.8%, and 2.2–2.8 GPa, respectively. These polymers also showed excellent thermal stability with glass transition temperatures in the range of 326–352 °C, 10% weight loss temperatures in the range of 538–574 °C, and the weight residue more than 57% at 800 °C in nitrogen. Moreover, as for the optical properties, these PFIs exhibited a strong optical absorption in the ultraviolet region (290–370 nm) and photoluminescence in dilute chloroform solution or solid state.     

Synthesis of AB‐type block copolymers containing benzoxazole and anthracene groups by ATRP and fluorescent property

Two functional monomers, methacrylic acid 4‐(2‐benzoxazol)‐benzyl ester (MABE) containing the benzoxazole group and 4‐(2‐(9‐anthryl))‐vinyl‐styrene (AVS) containing the anthracene group were synthesized by rational design. The MABE was polymerized via atom transfer radical polymerization (ATRP) using ethyl 2‐bromoisobutyrate (EBIB) as initiator in CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine (PMDETA) catalyst system; block copolymers poly(MABE‐b‐AVS) was obtained, which was conducted by using poly(MABE) as macro‐initiator, AVS as the second monomer, and CuBr/PMDETA as catalyst. The constitute of two monomers in block copolymers poly(MABE‐b‐AVS) by ATRP could be adjusted, that is the constitute of the benzoxazole group and the anthracene group could be controlled in AB‐type block copolymers. Moreover, the fluorescent properties of homopolymers poly(MABE) and block copolymers poly(MABE‐b‐AVS) were discussed herein. With the excitation at λ_ex = 330 nm, the fluorescent emission spectrum of poly(MABE) solution showed emission at 375 nm corresponding to the benzoxazole‐based part; with the same excitation, the fluorescent emission spectrum of poly(MABE‐b‐AVS) solution showed a broad peek at 330–600 nm when the monomer AVS to the total monomers mole ratio was 0.31, and the fluorescent emission spectrum of poly(MABE‐b‐AVS) in film state only showed one peak at 525 nm corresponding to the anthracene‐based unit that indicated a complete energy transfer from the benzoxazole group to the anthracene group. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3894–3901, 2007