氨基呋咱氧化为氨基硝基呋咱的合成研究

研究开发了将氨基呋咱转化为氨基硝基呋咱新的高收率氧化方法. 采用甲烷磺酸为介质, 以过氧化氢、碱或碱土金属和胺为基的氧化物(如钨酸钠或过硫酸铵)混合物的新氧化体系[H2O2/CH3SO3H/Na2WO4或(NH4)2S2O8]代替以硫酸为介质的过氧化氢和过硫酸铵混合物氧化体系, 分别对3,4-二氨基呋咱(DAF)、3,3’-二氨基-4,4’-氧化偶氮呋咱(DAAF)和3,3’-二氨基-4,4’-偶氮呋咱(DAAzF)进行氧化, 以高于65%的产率获得了3-氨基-4-硝基呋咱(ANF)和3-氨基-3’-硝 基-4,4’-氧化偶氮呋咱(ANAF), 并以15%的收率合成得到新化合物3-氨基-3’-硝基-4,4’-偶氮呋咱(ANAzF). 研究表明甲烷磺酸/过氧化氢/碱或碱土金属和胺为基的氧化物混合物是制备同时含有氨基和硝基基团的系列呋咱化合物非常有效的氧化体系.     

含2,6-二甲酰胺基吡啶单元的大环合成、结构及其对四面体构型阴离子的络合性质

采用前体二胺N,N’-(3-胺基苯基)-2,6-二甲酰亚胺吡啶(1)和5,5’-亚甲基双水杨醛(2)进行缩合反应得到含酚羟基的 [1+1] 席夫碱大环L1, 将其中席夫碱C=N双键还原得到环状骨架更具柔性的饱和大环L2. 通过1H NMR、FABMS和元素分析等对大环组成进行了表征, 并通过X射线单晶衍射解析了两个大环的晶体结构. 采用UV-Vis 光谱滴定技术对大环与系列阴离子的络合作用进行了考察, 结果表明席夫碱大环L1对四面体构型的阴离子H2PO4-、 HP2O73-和H2P2O72-有明显的选择性识别作用, 进一步通过UV-Vis 光谱、核磁滴定等技术获得了识别反应的配位比及平衡常数(K), L1对3个磷酸阴离子的络合能力依H2PO4-、HP2O73-和H2P2O72-顺序递增。     

三种新型二苯砜氮杂环蕃N,N’-二对甲苯磺酰基-1,m-二氮杂[m.1]对环蕃-n-砜的合成与表征(m＝8,10,12; n＝15,17,19)

以N,N’-二对甲苯磺酰基-4,4’-二氨基二苯砜与二溴代烷为原料, 高度稀释条件下合成了三种新型有硫原子桥连的氮杂环蕃N,N’-二对甲苯磺酰基-1,8-二氮杂[8.1]对环蕃-15-砜(C); N,N’-二对甲苯磺酰基-1,10-二氮杂[10.1]对环蕃-17-砜(D); N,N’-二对甲苯磺酰基-1,12-二氮杂[12.1]对环蕃-19-砜(E). 提供了三种环蕃化合物的合成方法. 用IR, 1H NMR和元素分析证实了新化合物结构. 分析了化合物D的单晶结构数据, 为环蕃化合物的空间结构研究提供了晶体学依据.     

水介质中9,10-二芳基吖啶的洁净合成

水介质中在十二烷基磺酸钠(SDS)催化下, 席夫碱与双甲酮反应合成了一系列9,10-二芳基吖啶衍生物, 同时分离得到一种中间产物. 所有产物的结构通过红外光谱和1H NMR光谱确定, 产物10-(4-氯苯基)-9-(4-甲氧基苯基)-3,3,6,6-四甲基-3,4,6,7,9,10-六氢化吖啶-1,8(2H,5H)-二酮(3i)和中间产物2-{4-氯苯基-[2-(4-甲氧基苯基氨基)-4,4-二甲基-6-氧代环已-1-烯基]甲基}-3-羟基-5,5-二甲基环已-2-烯酮(4h)的结构还通过单晶X射线衍射分析确证.     

新型含均三唑席夫碱型大环化合物的合成及其抗菌活性

5-取代-4-氨基-3-巯基-1,2,4-均三唑1a～1d与1,3-二氯-2-丙醇在超声辐射条件下缩合得S,S'-取代双(氨基均三唑)2a～2d,其与2,4-二羟基-5-乙酰苯乙酮在聚乙二醇-600催化下缩环合简便制得新型含均三唑席夫碱型大环化合物3a～3d,其结构经元素分析,1H NMR,IR和MS等进行确证,并测试了目标化合物的体外抗菌活性.     

新型交联磺化聚醚偶酰酮的合成及其物理性能

以对氟苯甲醛为原料,依次经过安息香缩合、亲核取代和脱甲氧基化反应制得二酚类单体——4,4’-二[(4-羟基)苯氧基]-二苯偶酰(3);3与4,4’-联苯二酚和3,3’-二磺酸钠基-4,4’-二氟二苯甲酮进行亲核缩聚反应,合成了一系列链状磺化聚醚偶酰酮聚合物(6a～6d)并制得质子膜(F-6a～F-6d);以3,3’-二氨基联苯胺为交联剂,6a～6d经缩环反应合成了新型交联结构的磺化聚醚偶酰酮(8a～8d)并制得具有不同离子交换容量的质子膜(F-8a～F-8d),6a～6d与8a～8d的结构经1H NMR和IR表征。物理性能研究结果表明,F-8a～F-8d具有较高的热稳定性和质子传导率。     

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。     

开环葫芦脲在水中对芳烃和芳醛的增溶和对腙大环形成的促进作用

利用核磁实验,研究了并入四个磺酸根或羧酸根的高水溶性开环葫芦脲对疏水性芳烃和芳醛的水相增溶作用.并入四个磺酸根的开环葫芦脲acCB-1能显著提高包括三联苯、4,4’-二甲基联苯和联苯-4,4’-二甲醛在内的芳烃和芳醛的水溶性,其中4,4’-二甲基联苯的溶解度可以提高到8.9 mmol/L,联苯-4,4’-二甲醛的溶解度可以提高到11.2 mmol/L.并入四个羧酸根的acCB-2可以把五氟甲苯和六氟苯在水中的溶解度提高到5.6和3.0 mmol/L.acCB-1还可以通过增溶芳香醛,促进其与酰肼反应形成腙.这一促进作用可以进一步应用于促进两个芳香二醛和一个芳香二酰肼在水中的反应,制备常规条件下不能形成的两个芳香腙大环.     

含有三苯胺环类席夫碱的合成

以4,4’-二甲酰基三苯胺为原料,通过Wittig和胺醛缩合反应合成了两个含有三苯胺环席夫碱类化合物——4-(对甲基苯乙烯基)-4’-亚(α-萘胺)甲基三苯胺和4-(对甲基苯乙烯基)-4’-亚(2-氨基芴)甲基三苯胺,其结构经1H NMR,13CNMR和IR确证。     

席夫碱大环的合成及其对稀土金属离子的识别研究

利用2,6-二(2'-甲酰基苯氧亚甲基)吡啶(1)分别与间苯二酚-二(4-氨基苯基)醚(2)和邻苯二酚-二(4-氨基苯基)醚(3)进行缩合得到席夫碱大环化合物L1和L2。用间苯二酚-二(2-甲酰基苯基)醚(4)与2缩合得到席夫碱大环化合物L3。采用1H NMR、IR、质谱和元素分析等对L1、L2和L3的组成进行表征,采用X射线单晶衍射技术测定了L2和L3的晶体结构。用UV-Vis光谱滴定技术对L1、L2和L3与系列稀土离子的键合作用分别进行了考察,结果表明,L1对Ce3+和Eu3+具有选择性识别作用,配位作用的键合比均为1∶1,键合常数依次分别为8.27×103和3.58×103L/mol。     

Synthesis and properties of a novel polyester containing bithiazole

A novel Schiff base type polyester containing 2,2’-diamino-4,4’-bithiazole(DABT) was prepared by low-temperature interface polycondensation of 1,4-benzenedicarbonyl dichloride with 4,4’-(4,4’-bithiazole-2,2’-diylbis(imine-2,1-diyl)diphenol(BDDP), which is derived from a 2,2’-diamino-4,4’-bithiazole(DABT) Schiff base reacted with a 4-hydroxybenzaldehyde monomer.The newly generated polyester was evaluated based on characterization of its solubility,FTIR spectroscopy,elemental analysis,X-ray diffraction measurements and thermogravimetric analysis(TGA) studies.     

Synthesis,spectroscopic, DNA cleavage and antibacterial activity of binuclear schiff base complexes

The binuclear Schiff base complexes are formed newly using different transition metals at their stable oxidation state as Cu(II), Ni(II), and VO(II). 3,3′,4,4′-tetraminobiphenyl and 2-aminobenzaldehyde were condensed to form a new Schiff base ligand having an two N₄ group responsible for better chelating to the metal centers. The ligand and their complexes have been established by analytical, spectral and electrochemical data. The interaction studies of the complexes with CT-DNA were carried out using cyclic voltammetry, viscosity measurements and fluorescence spectroscopy. The free ligand and their metal complexes were screened for their antimicrobial activities against the following species: Klebsiella pneumoniae, Escherichia coli and Staphylococcus aureus. A comparative study of minimum inhibitory concentration (MIC) values of the Schiff base and its complexes indicate that the metal complexes exhibit higher antibacterial activity than the free ligand.     

Design of Binaphthyl‐Modified Symmetrical Chiral Phase‐Transfer Catalysts: Substituent Effect of 4,4′,6,6′‐Positions of Binaphthyl Rings in the Asymmetric Alkylation of a Glycine Derivative

A series of symmetrical chiral phase‐transfer catalysts with 4,4′,6,6′‐tetrasubstituted binaphthyl units have been designed, and these aryl‐ and trialkylsilyl‐substituted phase‐transfer catalysts, which included a highly fluorinated catalyst, were prepared. The chiral efficiency of these chiral phase‐transfer catalysts was investigated in the asymmetric alkylation of tert‐butylglycinate–benzophenone Schiff base under mild phase‐transfer conditions, and the eminent substituent effect of the 4,4′,6,6′‐positions of the binaphthyl units on enantioselection was observed. In particular, the OctMe₂Si‐substituted catalyst was found to be highly efficient for the phase‐transfer alkylation of tert‐butylglycinate–benzophenone Schiff base with various alkyl halides, including sec‐alkyl halides. The highly fluorinated catalyst was also utilized as a recyclable chiral phase‐transfer catalyst by simple extraction with fluorous solvents.     

Synthesis,spectroscopic, electrochemical,DNA binding and photocleavage studies on coordination compounds of bis(4-aminophenyl)methane based novel Schiff bases

Two novel Schiff bases, 4,4′-methylenedianilidene-bis(3-methoxy-4-hydroxy-benzaldehyde) (L₁) and 4,4′-methylenedianilidene-bis(3,4-dimethoxybenzaldehyde) (L₂), have been prepared by condensing 4,4′-methylenedianiline (MDA) with vanillin and 3,4-dimethoxybenzaldehyde (DMB) respectively in ethanolic medium. Metal complexes of the above Schiff bases are prepared from salts of Cu(II), Zn(II), Co(II) and VO(IV). They are characterized by elemental analysis, molar conductivity, magnetic moment measurements, IR, ¹H NMR, UV-Vis., FAB Mass, and EPR spectra. The elemental analysis data exhibit the formation of 1: 1 [M: L] ratio. The mode of bonding and the geometry of the complexes have been confirmed on the basis of IR, UV-Vis. and magnetic moment measurements. These data reveal a square-planar geometry for all the complexes except VO(IV) which has square-pyramidal geometry. The molar conductance measurements of the Schiff base complexes reveal the existence of non-electrolytic nature. The interactions of complexes with calf thymus DNA (CT-DNA) have been investigated by electronic absorption spectroscopy, viscosity measurements and cyclic voltammetry. The results indicate that the complex can bind to DNA by intercalation modes. The Schiff bases and their metal complexes have been evaluated for their antifungal and antibacterial activities against different species of pathogenic fungi and bacteria and their results are compared with standard drugs.     

Facile synthesis of some novel triazolo[3,4-b]thiadiazines and triazolo[4,3-b]tetrazines

4-Amino-5-ethyl-4H-1,2,4-triazole-3-thiol was used as a key intermediate for the synthesis of triazolo[3,4-b][1,3,4]thiadiazines, triazolo[4,3-b][1,2,4,5]tetrazines and Schiff’s base via reactions with various hydrazonoyl halides and salicyaldehyde, respectively. Moreover triazolyl-N-N′-triazole derivatives were prepared from reaction of Schiff’s base with various hydrazonoyl halides. The structures of all the newly synthesized heterocyclic compounds were established by considering elemental analysis and spectral data.     

一种基于共保护策略合成谷胱甘肽的新方法

报道了一种采用谷氨酸席夫碱Ni(II)配合物共保护L-谷氨酸α-氨基和α-羧基合成谷胱甘肽(γ-L-谷氨酰-L-半胱氨酰-甘氨酸)的新方法. 首先由手性助剂——2-[N-(N’-苄基-脯氨酰)氨基]二苯甲酮(1)、六水合氯化镍和L-谷氨酸反应, 得到谷氨酸席夫碱Ni(II)配合物2, 产率为98%; 进而采用二异丙基碳二亚胺(DIC)/1-羟基-苯并三氮唑(HOBt)复合缩合剂法与S-苄基-L-半胱氨酸反应, 得到S-苄基-γ-L-谷氨酰-L-半胱氨酸席夫碱Ni(II)配合物3, 产率为90%; 接着同样采用DIC/HOBt复合缩合剂法与甘氨酸反应, 得到S-苄基-γ-L-谷氨酰-L-半胱氨酰-甘氨酸席夫碱Ni(II)配合物4, 产率为95%; 然后稀酸水解配合物4, 得到S-苄基-γ-L-谷氨酰-L-半胱氨酰-甘氨酸(5), 产率为70%; 最后采用甲酸铵催化转移氢化脱除S-苄基, 得到谷胱甘肽(6), 产率为87%. 中间产物和终产物的结构经由旋光, 1H NMR, 13C NMR和HRMS表征.     

Synthesis and properties of oligomers containing substituted bithiazole rings

A series of novel polyimide and poly(Schiff base) oligomers containing substituted bithiazole rings were designed and synthesized, for the first time, by polycondensation of 5,5^′-dimethyl-2,2^′- diamino-4,4^′-bithiazole (MDABT) with dianhydrides (pyromellitic dianhydride, 3,3^′-4,4^′-benzophenone tetracarboxylic dianhydride and bis (3,4-dicarboxyphenyl) ether dianhydride), and dialdehydes (oxalic aldehyde, isophthalaldehyde and terephthalaldehyde). The structure of the oligomers was determined by IR and ¹H NMR spectroscopy, and elemental analysis. The oligomers showed good thermal stability. The Fe²⁺ complex of poly(Schiff base), synthesized from MDABT with oxalic aldehyde (PMTOA), was prepared with 13.7% Fe content and found to be a ferromagnet at low temperature.     

Synthesis and magnetic properties of novel poly(Schiff base)‐Fe2+ complexes

Three polymer‐Fe²⁺ complexes were synthesized from Fe²⁺ and poly(Schiff base)s. The poly(Schiff base)s were prepared from 2,2′‐diamino‐4,4′‐bithiazole (DABT) with phthalaldehyde, 5,5′‐methylenebis(salicylaldehyde) (MBSA) and terephthalaldehyde, respectively, and characterized by IR, XPS, NMR and ESR spectroscopy. The magnetic behavior of these polymer‐Fe²⁺ complexes was examined as a function of magnetic field strength and temperature (5–300 K), respectively. The hysteresis loops were also studied. Based on these results, several novel ferromagnets were obtained.     

Synthesis,characterization and dyeing performance of new bisazo–bisazomethine disperse dyes

New bisazo–bisazomethine disperse dyes were prepared by the coupling of diazotized solutions of various aromatic amines with 2,2′-{methylenebis[4,1-phenylenenitrilomethylylidene]}diphenol (Schiff base). Schiff base (SB) was prepared by the condensation of 2-hydroxybenzaldehyde with 4,4′-diaminodiphenylmethane (DDM). The resultant dyes were characterized by elemental analysis, IR and ¹H NMR spectral studies. The UV–visible absorption spectral data were investigated in dimethylformamide (DMF) and are discussed in terms of structure property relationship. The dyes when applied on polyester fabric, gave golden yellow to reddish brown shades having fairly good to good light fastness, very good to excellent washing, perspiration and sublimation fastness and good to very good rubbing fastness properties.