双季铵盐化合物的结构表征与抗菌性能测试

将N,N-二甲基乙醇胺、N-甲基二乙醇胺分别接枝到1,3-二溴丙烷的两端进行季铵化反应,得到N1,N3-二羟乙基-N1,N1,N3,N3-四甲基-1,3-丙二胺二溴盐(QAS-1)和N1,N1,N3,N3-四羟乙基-N1,N3-二甲基-1,3-丙二胺二溴盐(QAS-2)。采用傅立叶变换红外光谱(FTIR)、核磁共振(NMR)和元素分析确证了其结构,以抑菌圈法和试管二倍稀释法评价了两者对5种菌株的抗菌活性。结果显示,它们对所选菌株均具有一定的抗菌活性,其中对白色念珠菌的最小抑菌浓度(MIC)分别为100 mg·L~(-1)和50 mg·L~(-1)。扫描电子显微镜(SEM)和透射电子显微镜(TEM)显示,QAS-1对金黄色葡萄球菌的抗菌作用机理可能为,带正电荷的季铵盐吸附在细菌表面,破坏细胞膜,导致细胞质外流从而杀灭细菌。细胞毒性显示QAS-1对人正常肝细胞(LO2)和人永生化表皮细胞(HaCat)的IC_(50)值分别为110.34 mg·L~(-1)和92.68 mg·L~(-1),细胞毒性显著低于阳性药。该研究说明该类季铵盐在抗菌领域具有潜在的应用价值。     

Synthesis and light absorption of benzotellurazole crown ether cyanine dye

Various methods for synthesis of 2-methyl-5,6-(1,4,7,10,13-pentaoxatridecamethyl-ene)benzotellurazole (8) are described. Under different conditions, alkylation of compound 8 with methyl iodide gave telluronium salt 1,2-dimethyl-5,6-(1,4,7,10,13-pentaoxatridecamethylene)benzo-tellurazolium iodide (15) or quaternary ammonium salt 2,3-dimethyl-5,6-(1,4,7,10,13-pentaoxatri-decamethylene)benzotellurazolium iodide (14) in high yields, repectively. The cyanine dye 3,3'-dimethyl-5,6,5',6'-bis(1,4,7,10,13-pentaoxatridecamethylene)telluracarbocyanine iodide (16) is obtained by condensation of 14 with ethyl orthoformate in acetic anhydride. The visible absorption of the cyanine dye is also discussed.     

Crosslinked QA‐PEI nanoparticles: synthesis reproducibility,chemical modifications,and stability study

Quaternary ammonium polyethylenimine (QA‐PEI) nanoparticles were synthesized by PEI crosslinking and alkylation with octyliodide followed by quaternization by methyl iodide. The present study focuses on the reproducibility of particles formation with respect to particle size, positive charge, oxidative, thermal stability and antibacterial activity. The QA‐PEI‐based nanoparticles with particle size in the range of 160–190 nm were synthesized in high reproducibility and showed high chemical stability against environmental changes including exposure to different oxidizers and storage conditions. QA‐PEI nanoparticles incorporated in dental restorative resin composites at 2% w/w demonstrated strong antibacterial activity. Copyright © 2013 John Wiley & Sons, Ltd.     

Rigid core vinamidinium salts and their N,N'-rotamers

The power of proton magnetic resonance spectroscopy to unravel stereochemical details is amply demonstrated. O-Methylation of 3-methylamino-5,5-dimethyl-2-cylohexen-1-one (1a) produces stable diastereomers, (Z)- and (E)-N-(3-methoxy-5,5-dimethyl-2-cyclohexen-1-ylidine)-N-methylaminium iodide (2a). As predicted by computation and confirmed by spectroscopy, the (Z)-vinylogous imidate salt predominates. Reaction of 2a with primary and secondary amines furnished a number of vinamidinium salts, including N-(3-methylamino-5,5-dimethyl-2-cyclohexen-1-ylidene)-N-methylaminium iodide (3a). Two rotamers of 3a were identified and characterized. A substantial number of additional compounds 2 and 3 are included in the study.     

近红外菁染料敏化的准固态太阳电池的光电化学研究

一个新型的近红外五甲川菁染料敏化剂(Cy)通过3,3-二甲基-1-乙基-2-[4-(N-苯乙酰氨基]-1,3-丁二烯-1-基]-3H-苯并[e]吲哚碘盐和5-羧基-1-丁基-2,3,3-三甲基-3H-吲哚碘盐的Knoevenagel缩合反应合成, 其结构用核磁、质谱和紫外等方法进行了确定; 使用疏水性气相法纳米SiO2 R974固化1-丁基-3-丙基咪唑碘离子液体制备了一种新的准固态电解质, 将其应用于菁染料(Cy)敏化的太阳电池, 对该染料敏化的准固态太阳电池的光电化学性能进行了研究. 在AM1.5G标准光源下, 得到1.49%的光电转换效率. 此方法对拓展准固态染料敏化太阳电池的研究具有一定的意义.     

Synthesis of 3-substituted 7-(3,3-dimethyl-1-triazeno)-10-methylphenothiazines as potential antitumor agents

A series of 3-substituted (chloro, bromo, fluoro or methyl) 7-(3,3-dimethyl-1-triazeno)-10-methylphenothiazines were synthesized as potential antitumor agents. Treatment of p-substituted anilines with ammonium thiocyanate in the presence of bromine gave 6-substituted 2-aminobenzthiazoles which, after methylation with methyl iodide were hydrolyzed in 50% potassium hydroxide to give 5-substituted 2-methylaminothiophenols in moderate yield. Condensation of methylaminothiophenols with 3,4-dichloronitrobenzene in ethanol under an atomsphere of nitrogen gave adducts which were cyclized in dimethylformamide under the catalysis of copper and cuprous iodide to give 3-substituted 7-nitro-10-methylphenothiazines. The nitro group was reduced to the amino function with stannous chloride. Diazotization of the amines followed by coupling with dimethylamine gave the corresponding triazenes.     

Silver Chloride Loaded Mesoporous Silica Particles and Their Application in the Antibacterial Coatings on Denture Base

Thiol-functionalized MCM-41 type mesoporous silica particles（MSPs） were prepared and loaded with silver chloride to act as antibacterial agents. The antibacterial activity of the silver chloride loaded MSPs（AgCI-MSPs） was evaluated by the minimum bactericidal concentration（MBC） against Candida albieans（ATCC 10231）. The AgC1-MSPs with the highest antibacterial activity were then dispersed in hybrid coatings with different mass ratios to fabricate antibacterial coatings. The antibacterial activity of the coatings was tested against Candida albicans{ATCC 10231） and Streptococcus mutans（ATCC 25175）. The resulting antibacterial coatings exhibited high antibacterial activity, good adhesion to the substrate and high hardness.     

The first 1-alkyl-3-perfluoroalkyl-4,5- dimethyl-1,2,4-triazolium salts

Syntheses of quaternary 1-alkyl-3-perfluoroalkyl-4,5-dimethyl-1,2,4-triazolium iodides have led to a variety of new quaternary salts via metathesis reactions. 1,4,5-Trimethyl-3-trifluoro-methyl-1,2,4-triazolium iodide (6) with LiN(SO(2)CF(3))(2), KSO(3)CF(3), AgClO(4), AgBF(4); 1-(3-fluoropropyl)-3-trifluoromethyl-4,5-dimethyl-1,2,4-triazolium iodide (7) with LiN(SO(2)CF(3))(2); and 1,4,5-trimethyl-3-perfluorooctyl-1,2,4-triazolium iodide (8) with LiN(SO(2)CF(3))(2), AgClO(4), AgBF(4) gave excellent yields of new thermally stable and relatively low melting quaternary salts. The structure of 1,4,5-trimethyl-3-perfluorooctyl-1,2,4-triazolium tetrafluoroborate (11c) was confirmed by single-crystal X-ray analysis. Although the molecular weight of 11c (cation) is 3-fold greater than that of the 3-trifluoromethyl derivative 9d, its melting point is 32 degrees C lower.     

Laser photolysis studies of spiropyran-merocyanine aggregate formation in solution

The photoinduced processes leading to formation of J-aggregate stacks of 1-(β-methacryloxyethyl)-3,3-dimethyl-6′- nitrospiro-(indoline-2,2′-[2H-[2H-1] benzopyran) d its associated ring opened merocyanine form B have been determined by N₂-laser transient spectroscopy. Detailed mechanisms for formation of complexes AB, A₂B, and J-aggregate stacks (A₂B) _n in aliphatic and aromatic solvents are presented.     

Synthesis and anti-bacterial activities of some novel Schiff bases derived from aminophenazone

A series of 1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one-containing Schiff bases were synthesized, characterized and screened for their antibacterial activities. The structures of the synthesized compounds were established by spectroscopic (FT-IR, 1H-NMR, 13C-NMR, MS) and elemental analyses. The anti-bacterial activities (with MIC values) of compounds were evaluated. The anti-bacterial screening results reveal that among the six compounds screened, four compounds showed moderate to good anti-bacterial activity. Among the tested compounds, the most effective compounds against four bacterial strains, viz. Escherichia coli, Staphylococcus aureus, Salmonella typhimurium and Streptococcus pyogenes, are [(2-chlorobenzylidene)amino]-1,5-dimethyl-2-phenyl-1,2-dihydropyrazol-3-one (4) and [(1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-ylimino)methyl]benzonitrile (5) with MIC values of 6.25 μg/mL.     

Synthesis,characterization and in vitro antibacterial evaluation of 1-(7,7-dimethyl-2-morpholino-5,6,7,8-tetrahydroquinazolin-4-yl)piperidine-4-carboxamide derivatives

A series of six novel 1-(7,7-dimethyl-2-morpholino-5,6,7,8-tetrahydroquinazolin-4-yl)piperidine-4-carboxamide derivatives has been synthesized and characterized using various spectral techniques (¹H and ¹³C NMR, LCMS, IR). The antibacterial activities of these compounds have been screened against nine different Gram-positive and Gram-negative bacterial strains. The results show that quinazoline derivatives containing thiazole ring 2a and 2b exhibit good antibacterial activity amongst the compounds under investigation.     

Synthesis,spectral characterization and biological evaluation of novel 1-(2-(4,5-dimethyl-2-phenyl-1H-imidazol-1-yl)ethyl)piperazine derivatives

A simple, highly useful synthesis of 1-(2-(4,5-dimethyl-2-phenyl-1H-imidazol-1-yl)ethyl)piperazine derivatives is achieved by a four component cyclo condensation of diacetyl, aromatic aldehyde, 2-(piperazin-1-yl)ethanamine and ammonium acetate using SO₄²⁻/Y₂O₃ as a catalyst in ethanol. The synthesized compounds were characterized by IR, ¹H and ¹³C NMR and mass spectral studies. All the synthesized compounds were screened for their in vitro antimicrobial studies. Among the newly synthesized compounds 5d, 5e, 5h and 5m showed excellent antibacterial and antifungal activities when compared to the standard drugs.     

Rubesanolides C-E: abietane diterpenoids isolated from Isodon rubescens and evaluation of their anti-biofilm activity

Phytochemical study of the leaves of the medicinal plant Isodon rubescens led to the isolation of three novel abietane diterpenoids, rubesanolides C-E (1-3). These diterpenes contain a unique γ-lactone subgroup formed between C-8 and C-20. Their structures were determined from analysis of spectroscopic data, and were further confirmed by X-ray crystallographic data. The compounds were evaluated for their antibacterial activity, and rubesanolide D (2) demonstrated inhibition activity against biofilm formation of the dental bacterium Streptococcus mutans.     

2,4,5-三苯基咪唑Schiff碱的合成及其抑菌活性

以联苯甲酰、对硝基苯甲醛和乙酸铵为原料,经缩合和还原反应制得2-(4-氨基苯基)-4,5-二苯基咪唑(2);2再与芳香醛缩合制得三个新型的2,4,5-三苯基咪唑Schiff碱衍生物(3a～3c),其结构经1H NMR,IR和MS表征。初步抑菌活性测试结果表明,3a～3c对大肠杆菌,苏云金杆菌和枯草芽孢杆菌均有较好的抑菌活性。     

Synthesis and antibacterial activity of novel pyrano[2,3-d]pyrimidine-4-one–3-phenylisoxazole hybrids

A series of ethyl 2,7-dimethyl-4-oxo-5-phenyl-3-[(3-phenylisoxazol-5-yl)methyl]-3,5-dihydro-4H-pyrano[2,3-d]pyrimidine-6-carboxylates was synthesized and screened for antibacterial activity against Gram positive and Gram negative bacterial species. All new compounds were characterized by ¹H, ¹³C NMR, IR, and mass spectra. The results of the antibacterial study indicated that all compounds exhibited good to excellent antibacterial activity.

     

Synthesis and antimicrobial agents of thiazolidinone derivatives from benzocyclohepetenone

A series of benzosuberone coupled piperazin-1-yl thiazolidin-4-one derivatives 6a-j were synthesized from 3-(2-[9-chloro-2,3-dimethyl-6,7-dihydro-5H-benzo[7]annulen-8-yl]-4-oxothiazolidin-3-yl)propanoic acid ( 4 ) and substituted piperazines/secondary amines 5a-j using 1-hydroxy benzotriazole, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride and triethyl amine in good yields and their structures were characterized by ¹H NMR, ¹³C NMR, IR, and Mass spectra. The newly synthesized compounds were evaluated for their antimicrobial activity against bacterial strains and a fungal strain. Compounds 6f and 6g were indicated promising and broad spectrum antibacterial activity.     

Synthesis and antibacterial activities of water‐soluble methacrylate polymers containing quaternary ammonium compounds

New water‐soluble methacrylate polymers with pendant quaternary ammonium (QA) groups were synthesized and used as antibacterial materials. The polymers with pendant QA groups were obtained by the reaction of the alkyl halide groups of a previously synthesized functional methacrylate homopolymer with various tertiary alkyl amines containing 12‐, 14‐, or 16‐carbon alkyl chains. The structures of the functional polymer and the polymers with QA groups were confirmed with Fourier transform infrared and ¹H and ¹³C NMR. The degree of conversion of alkyl halides to QA sites in each polymer was determined by ¹H NMR to be over 90% in all cases. The number‐average molecular weight and polydispersity of the functional polymer were determined by size exclusion chromatography to be 32,500 g/mol and 2.25, respectively. All polymers were thermally stable up to 180 °C according to thermogravimetric analysis. The antibacterial activities of the polymers with pendant QA groups against Staphylococcus aureus and Escherichia coli were determined with broth‐dilution and spread‐plate methods. All the polymers showed excellent antibacterial activities in the range of 32–256 μg/mL. The antibacterial activity against S. aureus increased with an increase in the alkyl chain length for the ammonium groups, whereas the antibacterial activity against E. coli decreased with increasing alkyl chain length. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5965–5973, 2006     

呫吨酮并吡啶季铵盐的合成及其生物活性

以邻碘苯甲酸和8-羟基喹啉为原料,通过Ullmann反应合成了呫吨酮并吡啶(2),再将其进行季铵化反应合成了它的甲基及乙基季铵盐化合物3a和3b,用IR、NMR、MS及元素分析等测试技术对其结构进行了表征。运用四甲基偶氮唑盐微量酸反应比色法(MTT法)测得化合物3a和3b对体外培养人卵巢癌(A2780)、宫颈癌(Hela)、肺癌(SPC-A)和口腔上皮癌(KB)细胞的抑制作用均优于阳性对照药5-氟尿嘧啶(5-Fu)。溴乙锭置换荧光探针法测得化合物3a和3b与小牛胸腺DNA(CT-DNA)的表观结合常数分别为3.91×105和2.72×105L/mol,揭示目标化合物的抗癌活性可能与其跟DNA的相互作用有关。化合物3a和3b对乙酰胆碱酯酶(AChE)和丁酰胆碱酯酶(BuChE)均具有良好的选择性抑制活性,IC50值达μmol/L以下,与阳性对照药氢溴酸加兰他敏(Galantamine.HBr)近似,它们对AChE的抑制作用为非竞争性抑制。     

5,6-二甲基-2,3-吡嗪二甲酰胺-铜配合物的合成及其抗菌活性

以2,3-二甲基-5,6-二氰基吡嗪为原料,稀碱条件下不完全氧化得到配体5,6-二甲基-2,3-吡嗪二甲酰胺,再与醋酸铜在弱碱条件下合成5,6-二甲基-2,3-吡嗪二甲酰胺-铜配合物;采用牛津杯法预试验及试管二倍稀释法研究配体5,6-二甲基-2,3-吡嗪二甲酰胺及其配合物的抗菌活性。 对合成的配合物通过紫外光谱、红外光谱、差热-热重分析进行确证表征。 该配合物表现出较好的抑菌和杀菌作用,对大肠埃希菌的MIC和MBC均为50 mg/L,对金黄色葡萄球菌的MIC和MBC均为25 mg/L,而配体没有明显的抑菌杀菌作用,从而为临床疾病的治疗和食品添加剂的研发提供参考。     

Crystal structures and antibacterial properties of Cu(II) complexes containing an unsymmetrical N2O Schiff base ligand and bidentate N-donor heterocyclic co-ligands

Abstract

Three new Cu(II) Schiff base complexes with bidentate N-donor heterocyclic co-ligands, 2,2'-bipyridine (1), 1,10-phenanthroline (2), and 2,9-dimethyl-1,10-phenanthroline (3), were synthesized and characterized by FT-IR and UV-vis spectroscopy. Molecular structures of [C₂₀H₂₁CuN₄O](ClO₄) (1) and [C₂₄H₂₅CuN₄O](ClO₄) (3) were characterized by single-crystal X-ray crystallography. The Schiff base ligand is an N₂O-type ligand, which is the mono-condensed form of the reaction between 1,3-propanediamine and salicylaldehyde. The antibacterial activities of these complexes were investigated against one gram positive and four gram negative bacteria. Considerable antibacterial activity was obtained against both gram type bacteria. Complexes 2 and 3 with 1,10-phenanthroline and 2,9-dimethyl-1,10-phenanthroline, respectively, showed better antibacterial activity compared to 1 which has the 2,2'-bipyridine co-ligand.