- A BODIPY-based fluorescent sensor for the detection of Pt2+ and Pt drugs
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A BODIPY-based fluorescent sensor PS with an NO4S2 podand ligand was studied for the selective detection of Pt2+ over 21 cations as well as selected platinum drugs in aqueous medium. The platinum sensor PS shows 28-fold, 22-fold and 14-fold fluorescence turn-on enhancements to Pt2+, cisplatin and nedaplatin, and was thereby employed to detect platinum drugs in A-549 human lung cancer cells.
- Bian, Qingyuan,Kong, Fred Ka-Wai,Leung, Ken Cham-Fai,Ng, Maggie,Tang, Fung-Kit,Tse, Anfernee Kai-Wing,Tse, Yu-Chung,Yam, Vivian Wing-Wah,Zhu, Jiaqian
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Read Online
- Design, synthesis, linear and nonlinear photophysical properties of novel pyrimidine-based imidazole derivatives
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Novel donor-π-acceptor (D-π-A) and donor-π-acceptor-π-donor (D-π-A-π-D) type pyrimidine imidazole derivatives with flexible ether chains (L1 and L2) have been efficiently synthesized through improved Knoevenagel condensation and Ullmann reactions with high yields. Based on systematic photophysical investigations and theoretical calculations, the structure-property relationships can be described as follows: (1) the linear and nonlinear optical properties of the target chromophores change regularly with increasing the number of branches and the polarity of the solvents. (2) The single-substituted chromophore L2 exhibited a remarkable negative solvato-kinetic effect, while the double-substituted chromophore L1 showed a positive solvato-kinetic effect. Significant bathochromic shifting of the emission spectra and larger Stokes shifts were observed in polar solvents. (3) The two-photon absorption (TPA) cross-section results further demonstrated that their TPA cross section values (δ) increase notably with increasing branch number, and the presence of high π-delocalization could induce large size-scalable TPA enhancements. (4) By comprehensively considering the optical performance, cytotoxicity and solubility, L1 was identified as the better candidate for living cell (HepG2) imaging.
- Zhang, Qiong,Luo, Lei,Xu, Hong,Hu, Zhangjun,Brommesson, Caroline,Wu, Jieying,Sun, Zhaoqi,Tian, Yupeng,Uvdal, Kajsa
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Read Online
- Kinetic parameter estimation of solvent-free reactions monitored by 13C NMR spectroscopy, a case study: Mono- and di-(hydroxy)ethylation of aniline with ethylene carbonate
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The kinetics of solvent-free reactions can be followed in situ by 13C nuclear magnetic resonance (NMR) spectroscopy, provided that the reaction mixture can be maintained liquid at the monitoring temperature. The pros and cons of the technique and the correct translation of the signal intensities into concentrations are discussed. A good model for this investigation is the reaction of ethylene carbonate (1) with aniline (2) at 140°C, two alkylation products of N-mono- and N, N-bis-(2-hydroxy)ethylation of aniline form (compounds 3 and 4, respectively). The overall reaction occurs with heavy volume shrinking, so that the physical as well as the chemical features evolve during the course of the process. The chemical evolution is described by the kinetic constants k1 and k2 of the two N-alkylation steps, the physical evolution by the time-dependent activity coefficients α(t). Two complementary procedures are utilized for the determination of these parameters.
- Lucchini, Vittorio,Fabris, Massimo,NoE, Marco,Perosa, Alvise,Selva, Maurizio
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Read Online
- A Bis-Quinoline Appended Azobenzene Based Naked Eye Sensor for Selective Detection of Cd2+ Ion
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A new azobenzene chromophore (AZQU), appended with a bis-quinoline unit as a turn-on chemosensor for selective detection of Cd2+ ions, has been designed and synthesized. The fluorescent receptor AZQU has an excellent selectivity and sensitivity towards Cd2+ ions over other metal ions in CH3CN:H2O (80:20, v/v) solution. AZQU is red colored and non-fluorescent in the absence of Cd2+ ions, but upon addition of Cd2+ ions it turns colorless with appreciable fluorescence. This “off–on” type signaling behavior is attributed to the CHEF (chelation-enhanced fluorescence) effect of the quinoline unit and the change in color from red to yellow occurs by an ICT process with Cd2+. The association constant for AZQU?+?Cd2+ was calculated to be 1.68?×?105 L·mol?1 with binding in the 1:1 stoichiometric ratio.
- Hrishikesan, Elango,Manjunath, Rangasamy,Kannan, Palaninathan
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Read Online
- Synthesis of New Bis-1,2,4-Oxadiazoline Derivatives via 1,3-Dipolar Cycloaddition Reaction
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A series of novel bis-oxadiazoline derivatives 4 was synthesized via 1,3-dipolar cycloaddition reaction of bis-aldimines 3, and nitrile oxides generated in situ from various benzohydroximinoyl chlorides in the presence of Et3N. The target products were confirmed by IR,1H-NMR, and mass spectrometry.
- Chen, Fei,Zeng, Hua,Liu, Fang-Ming
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Read Online
- A fully-aqueous red-fluorescent probe for selective optical sensing of Hg2+ and its application in living cells
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A new red-fluorescent mercury ion sensor material is designed and synthesized, which is composed of a tweezer-shaped hydrophilic probe containing bifurcated soft-base atoms N and S coupled with 2-dicyanomethylene-3-cyano-4,5,5-trimethyl-2,5-dihydrofuran (TCF) unit. By virtue of the strong electron-accepting nature of TCF unit (as a push-pull chromophore), this designed sensor material can selectively detect Hg2+ over various tested metal ions in a 100% aqueous medium via naked-eye and photoluminescence (PL) observations. Theoretical and time-resolved photoluminescence measurements further confirmed the selectivity and reversibility of the probe towards Hg2+ via intramolocular charge transfer mechanism in this sensor material. Moreover, the living cell tests by confocal fluorescence images of this sensor material towards Hg2+ were also investigated. Finally, distinguished absorption changes and fluorescence quenching spectral appearances allowed us to present the selective optical indicator of Hg2+ via TCF moiety for the first time.
- Pola, Murali Krishna,Ramakrishnam Raju, Mandapati V.,Lin, Chein-Ming,Putikam, Raghunath,Lin, Ming-Chang,Epperla, Chandra Prakash,Chang, Huan-Cheng,Chen, San-Yuan,Lin, Hong-Cheu
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Read Online
- Hg2+ sensing in aqueous solutions: an intramolecular charge transfer emission quenching fluorescent chemosensors
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Compounds 4a and 4b, comprising an anthracene moiety as the fluorophore and a pair of dithiocarbamate functionalities as ligating groups, were designed as fluorescent chemosensors for Hg(II). In aqueous solvent systems, upon excitation, in addition to the normal emission bands of locally excited (LE) state of anthracene, both compounds show a prominent pH-independent intramolecular charge transfer (ICT) emissive band, which can be modulated by Hg2+ binding. The systems can be exploited to develop a fluorescent sensitive probe for Hg2+.
- Cheung, Sin-Man,Chan, Wing-Hong
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Read Online
- Synthesis, characterization and properties of NLO dye-containing polyurethane
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Polyurethane attached hemicyanine dye with tetraphenylborate anion was synthesized. This polymer was soluble in dimethylformamide and could be processed into thin film by spin coating. The poled polymer film showed a large second-order nonlinear optical coefficient (χ(2) = 4.0×10-7 esu) and good temporal stability.
- Moon,Shim,Lee
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Read Online
- Fluorescent probe molecule for detecting azo reductase based on coumarin derivative as well as preparation method and application of fluorescent probe molecule
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The invention provides a fluorescent probe molecule for detecting azo reductase based on a coumarin derivative as well as a preparation method and application of the fluorescent probe molecule, and belongs to the technical field of protease detection reagents. The fluorescent probe molecule prepared by the invention can provide a molecule combined with a specific biological enzyme-azo reductase, so that azo groups in a probe structure are reduced by the azo reductase, a fluorophore coumarin derivative is released, fluorescence of the probe molecule is changed, and an anticancer active drug phenylalanine mustard is released at the same time; therefore, the azo reductase in a liquid phase system is selectively identified and detected. Therefore, the invention provides the application of the fluorescent probe molecule in preparation of a reagent for detecting azo reductase and/or detection of Sn in a water body.
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Paragraph 0083; 0086
(2021/07/17)
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- A water-soluble BODIPY based ‘OFF/ON' fluorescent probe for the detection of Cd2+ ions with high selectivity and sensitivity
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A water-soluble dilithium salt BODIPY derivative (LiBDP) with appended dicarboxylate pseudo-crown ether [NO4] coordinating sites has been designed, synthesized and characterized successfully for the selective and sensitive recognition of Cd2+ in aqueous media. The chemosensor exhibits a remarkable increase in fluorescence intensity as well as a distinct color change upon the addition of Cd2+ over other environmentally and biologically relevant metal ions in H2O. The fluorometric response of LiBDP is attributed to the metal chelation-enhanced fluorescence (MCHEF) effect which has been confirmed by a strong association constant of 2.57 ± 1.06 × 105 M?1 and Job's plot, indicating 1?:?1 binding stoichiometry between LiBDP and Cd2+. Frontier molecular orbital analysis (obtained from DFT studies) also illustrates the turn-on fluorescence of the probe by blocking photoinduced electron transfer (PET) after coordination to Cd2+. The probe can detect Cd2+ in a competitive environment up to a submicromolar level in a biologically significant pH range. The sensor is proved to be reversible and reusable by the alternative addition of Cd2+ followed by S2?. The OFF/ON/OFF sensing behavior is utilized to construct an INHIBIT molecular logic gate based on the two inputs of Cd2+ and S2? and a fluorescence intensity at 512 nm as an output. The test paper experiment demonstrates the practical utility of LiBDP to monitor Cd2+ in an aqueous sample. Finally, the sensing probe was utilized to monitor Cd2+ in living cells.
- Maity, Apurba,Ghosh, Utsav,Giri, Dipanjan,Mukherjee, Devdeep,Maiti, Tapas Kumar,Patra, Sanjib K.
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supporting information
p. 2108 - 2117
(2019/02/12)
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- METALLOENZYME INHIBITOR COMPOUNDS
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Provided are compounds having HDAC6 modulating activity, and methods of treating diseases, disorders or symptoms thereof mediated by HDAC6.
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Page/Page column 146-147
(2018/09/28)
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- A straightforward one-pot synthesis of bioactive: N -aryl oxazolidin-2-ones via a highly efficient Fe3O4@SiO2-supported acetate-based butylimidazolium ionic liquid nanocatalyst under metal- and solvent-free conditions
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In the present study, we report the fabrication and characterization of novel acetate-based butylimidazolium ionic liquid immobilized silica-coated magnetic nanoparticles (IL-OAc@FSMNP). The synthesized nanocomposite proves its supremacy as an environmentally benign catalyst in the reaction of aniline and its derivatives with ethylene carbonate to form bioactive N-aryl oxazolidin-2-ones under metal-, ligand-, and solvent-free conditions. The catalyst offers excellent assemblies of hydrogen-bond donors and acceptors, which activate the substrates, thereby delivering good-to-excellent product yields with a conversion and selectivity of more than 99%. Additionally, mild reaction conditions, wide substrate scope, effortless catalytic recovery and recyclability of the catalyst up to eight consecutive cycles offer the potential for scale-up in various pharmaceutical applications.
- Gupta, Radhika,Yadav, Manavi,Gaur, Rashmi,Arora, Gunjan,Sharma, Rakesh Kumar
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p. 3801 - 3812
(2017/08/22)
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- METHOD FOR PRODUCING CIS- AND TRANS-ENRICHED MDACH
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A process for preparing trans-enriched MDACH, including: distilling an MDACH starting mixture in the presence of an auxiliary, which is an organic compound having a molar mass of 62 to 500 g/mol, a boiling point at least 5° C. above the boiling point of cis,cis-2,6-diamino-1-methylcyclohexane, and 2 to 4 functional groups, each of which is independently an alcohol group or a primary, secondary or tertiary amino group. The MDACH starting mixture includes 0 to 100% by weight of 2,4-MDACH and 0 to 100% by weight of 2,6-MDACH, based on the total amount of MDACH present in the MDACH starting mixture. The MDACH starting mixture includes both trans and cis isomers. Trans-enriched MDACH includes 0 to 100% by weight of 2,4-MDACH and 0 to 100% by weight of 2,6-MDACH, where the proportion of trans isomers in the mixture is higher than the proportion of trans isomers in the MDACH starting mixture.
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- Synthesis of 3-[4-(dimethylamino)phenyl]alkyl-2-oxindole derivatives and their effects on neuronal cell death
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Novel 3-[4-(dimethylamino)phenyl]alkyl-2-oxindole analogs were synthesized by either of the following two pathways: (1) a sequence of Knoevenagel condensation of oxindole with (4-dimethylamino)cinnamaldehyde–hydrogenation, or (2) alkylation of oxindole dianion with [(4-dimethylamino)phenyl]alkyl halides. Subsequent alkylation at C-3 and/or N-1 of the oxindole skeleton by anion-based methods provided additional substituted derivatives for structure-activity relationship studies. Their effects on neuronal cell death induced by oxidative stress were evaluated by lactate dehydrogenase assay. Compounds with the alkyl chain length of 2–4 significantly suppressed the neuronal cell death. No significant change occurred in the activity by substitution with less-polar groups. The stereochemistry at C-3 of the oxindole core was also irrelevant for the neuroprotective effects of these compounds.
- Furuta, Kyoji,Kawai, Yu,Mizuno, Yosuke,Hattori, Yurika,Koyama, Hiroko,Hirata, Yoko
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supporting information
p. 4457 - 4461
(2017/09/12)
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- Cu2O/nano-CuFe2O4: An efficient and magnetically recoverable catalyst for the ligand-free N-arylation of amines and nitrogen heterocycles with aryl halides
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An efficient strategy has been developed for the N-arylation of azoles and aliphatic amines with aryl halide using a Cu2O/nano-CuFe2O4 magnetic composite as the catalyst and KOH as the base. The methodology is found to be applicable to a variety of nitrogen-containing heterocycles, such as imidazole, indole, and pyrrole, as well as aliphatic amines in high yields with practical simplicity under cost-effective "ligand-free" conditions. The magnetic property of the catalyst allowed its fast separation from the reaction medium by an external magnet. Additionally, the inexpensive catalyst could be recycled for five consecutive runs with small drops in catalytic activity.
- Elhampour, Ali,Nemati, Firouzeh,Kaveh, Mahdieh
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supporting information
p. 223 - 225
(2016/03/01)
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- Synthetic technology of hydroxyethylaniline ester (III)
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The invention discloses a synthetic technology of hydroxyethylaniline ester (III). The synthesis process is shown by a chemical equation shown in the description. The technology has the following advantages: 1, the advantage of few instant reaction substances of a micro-channel reactor is used, so the flammable and explosive disadvantages of a hydroxyethylation reaction in a routine kettle are solved, the process safety is increased, and current chemical engineering safety operation requirements are met; and 2, the advantage of high mixing efficiency of the micro-channel reactor is used, the reaction can be carried out under solvent-free conditions when a hydroxyethylation reaction raw material is liquid, and when the excess amount of ethylene oxide is very small, so a reaction solution obtained after the hydroxyethylation reaction ends can be esterified in the micro-channel reactor, serial operation of two-step reactions is realized, and manpower and three wastes are greatly reduced. The technology is a new technology with simplified processes, and accords with environmental protection and safety requirements.
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Paragraph 0042; 0043
(2016/11/02)
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- Application of nitrogen mustard based piperlongumine compound in medicine
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The invention provides application of a nitrogen mustard based piperlongumine compound in medicine. On the basis of the research on the nitrogen mustard based piperlongumine compound for inhibiting the activity of malignant cells, it proves that the nitrogen mustard based piperlongumine compound has the good anti-tumor activity, and a new choice is provided for preparing anti-tumor medicine.
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Paragraph 0012; 0013
(2016/11/28)
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- Hybrid pharmacophore-based drug design, synthesis, and antiproliferative activity of 1,4-dihydropyridines-linked alkylating anticancer agents
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Two series of novel substituted 1,4-dihydropyridine derivatives incorporating nitrogen mustard pharmacophore hybrids without spacer DHP-M (4a-4d) and with ethyl spacer DHP-L-M (8a-8g) were designed and synthesized. They were subjected to in silico ADME prediction study to check their drug-like properties and evaluated for their cytotoxicity against: A 549 (lung), COLO 205 (colon), U 87 (glioblastoma), and IMR-32 (neuroblastoma) human cancer cell lines in vitro using 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay against chlorambucil and docetaxel. Majority of the test compounds exhibited moderate to significant cytotoxic activity. The highest activity in all the investigated cancer cells was displayed by DHP-M (4a). This may be due to the less steric hindrance offered by 4a.
- Singh, Rajesh K.,Prasad,Bhardwaj
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p. 1534 - 1545
(2015/04/21)
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- Green and efficient protocol for the synthesis of N-(2-hydroxyethyl)anilines by the alkylation reaction in ionic liquid
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A green and efficient protocol for the synthesis of N-(2-hydroxyethyl)anilines by the selective alkylation reaction in ionic liquid [BMIM]BF4 (1-butyl-3-methylimidazolium tetrafluoroborate) has been developed, eliminating the need for toxic and expensive catalysts and volatile organic solvents. The effects of the amount of ionic liquid, temperature, time, and substrate structure on the reaction were investigated. The conversion and selectivity of N-(2-hydroxyethyl)anilines obtained in ionic liquid [BMIM]BF4 are significantly increased in comparison to those traditional methods. Furthermore, the ionic liquid could be easily separated and reused at least five times. It provided a simple and efficient alternative way for the industrial synthesis of N-(2-hydroxyethyl)anilines.
- Guo, Hui,Zhuang, Yuwei,Cao, Jian,Zhang, Guobao
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p. 3368 - 3374
(2014/12/10)
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- Free-radical hydroxymethylation of ketimines generated in situ: A one-pot multicomponent synthesis of β,β-disubstituted-β-aminoalcohols
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We report how an acidic TiCl4-Zn/t-BuOOH system is able to promote the one-pot multicomponent synthesis of β,β-disubstituted- β-aminoalcohols via nucleophilic addition of a hydroxymethyl radical to activated ketimines generated in situ in methanol solvent. While ketimines are generally recognized as less reactive and less stable when compared with aldimines, Ti(IV) plays a key role in facilitating their formation and in enhancing their electrophilic character. As a consequence, the reaction occurs at room temperature and under non-anhydrous conditions in just 1 h, without requiring either the preformation of the ketimine or protection of the amino group. The scope of the reaction is widely explored and a possible mechanism is discussed.
- Rossi, Bianca,Pastori, Nadia,Clerici, Angelo,Punta, Carlo
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p. 10151 - 10156,6
(2020/09/02)
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- Synthesis, crystal structure, optical properties, DNA-binding and cell imaging of an organic chromophore
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An organic chromophore (4-[N, N- bis(2′-chloroethyl)anilino] ethenyl N-methyl pyridinium-N- methyl iodide) L was synthesized and fully characterized by elemental analysis, IR, 1HNMR spectra and single crystal X-ray diffraction analysis. One and two-photon fluorescence spectra for it were studied. Interestingly, L exhibited obvious two-photon absorption in the range from 700-850 nm in DMSO solution. The interactions between the chromophore and calf thymus DNA were investigated by absorption, fluorescence spectra and viscosity experiments. The results showed that the chromophore could interact with DNA in the mode of intercalation and be effectively used as fluorescent staining dye for cell imaging applications. Furthermore, the cell viability data for MCF-7 (Human breast carcinoma) cells indicated that the low-micromolar concentrations of the L are essentially non-toxic and can be applied in brighter two-photon fluorescent (TPF) bioimaging.
- Zhou, Shuangsheng,Zhang, Qiong,Tian, Xiaohe,Hu, Guiju,Hao, Fuying,Wu, Jieying,Tian, Yupeng
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scheme or table
p. 689 - 695
(2012/02/13)
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- Synthesis and structure-analgesic activity relationships of a novel series of monospirocyclopiperazinium salts (MSPZ)
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A series of monospirocyclopiperazinium salts were designed and synthesized to search for a peripherally-acting analgesic drug with low side effects. Extensive SAR studies revealed that a suitable NR2R3 was critical for the analgesic activity, which might be beneficial to expose the cationic nitrogen to bind to the receptor, and possibly interact with the receptor via π-π interaction. Introduction of substituting group on the N4-phenyl ring could improve the activity, and the best position was the 4-position. Compound 14n showed more potent analgesic activity (63%, 20 μM/kg, sc) and holds promise for development as a mechanically new analgesic drug.
- Lin, Song-Wen,Sun, Qi,Ge, Ze-Mei,Wang, Xin,Ye, Jia,Li, Run-Tao
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supporting information; experimental part
p. 940 - 943
(2011/03/21)
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- Steady-state and time-resolved investigations of a crown thioether conjugated with methylacridinium and its complexes with metal ions
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The crown thioether 9-[4-(4,7,10,13-tetrathia-1-azacyclopentadecyl]phenyl- N-methylacridinium perchlorate (TCMA) was synthesized and characterized with the aim to verify its ability to interact selectively with metal ions and substantiate the possibility to detect easily the presence of heavy metals in fluid samples. The spectroscopic properties of TCMA, alone and in the presence of metal ions, were therefore studied in polar solvents (MeCN and H 2O); in particular, steady-state UV-Vis spectrophotometric and fluorimetric techniques were used together with transient absorption spectroscopy with fs time resolution to investigate the spectral and dynamic properties of the lowest excited singlet state of TCMA and of TCMA/metal ion complexes. The absorption in the Vis region is characterized by a charge-transfer nature with the methylacridinium moiety acting as the electron-acceptor and the anilic group as the electron-donor. No emission from the S1 was detected both in MeCN and H2O, while a small S2 → S0 fluorescence emission (λmax = 485 nm and F = 0.0011) was detected in water. Time-resolved measurements with fs resolution of TCMA in MeCN have shown that the relaxed S1 state is reached ～0.6 ps after the laser pulse, while the S1 → S0 time constant is 3.7 ps. Among the investigated metal ions, only Fe3+ (in MeCN) and Hg2+ (in MeCN and H2O) were able to form stable complexes (association constant, Kass = 1-11 × 104 M-1) with TCMA. The S1 state of the TCMA/Mn+ complexes emits with low quantum yield (F = 0.0023-0.014) and decays with time constants much longer than TCMA itself, at least in the case of TCMA/Hg2+ in MeCN. This study showed that TCMA is a good candidate for colorimetric/ fluorimetric sensing of Hg2+ in aqueous media owing to its high selectivity towards metal ions. the Owner Societies.
- Giacco, Tiziana Del,Carlotti, Benedetta,Solis, Stefano De,Barbafina, Arianna,Elisei, Fausto
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experimental part
p. 2188 - 2195
(2011/09/30)
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- Synthesis and characterization of three novel nitrogen-containing macrolides
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Three novel nitrogen-containing macrolides have been synthesized by esterification. All of them have been characterized by infrared (IR), elemental analysis, mass spectra (MS), and 1H NMR spectroscopy, and their crystal structures were determined by single-crystal X-ray diffraction. The preparation methods and the intermolecular associations based on C-H···O hydrogen bonds and π-π stacking interactions are discussed.
- Leng, Xin,Yang, Bingqin,Liu, Yuanyuan,Xie, Yi,Tong, Jie
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experimental part
p. 930 - 934
(2011/10/11)
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- Synthesis of 2,2-Bipyridines via Suzuki-Miyaura Cross-Coupling
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For a long time, the Suzuki-Miyaura cross-coupling reaction could not be used for the synthesis of 2,2′-bipyridines due to the lack of sufficiently stable 2-pyridylboron compounds. Stabilized 2-pyridylboronic acid esters recently developed by Hodgson, however, were found to be ideally suited for this purpose. Two general protocols could be developed and demonstrated to be valuable alternatives, which can be used very efficiently for the synthesis of functionalized 2,2-bipyridines.
- Guetz, Christoph,Luetzen, Arne
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experimental part
p. 85 - 90
(2010/04/29)
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- The reaction of primary aromatic amines with alkylene carbonates for the selective synthesis of bis-N-(2-hydroxy)alkylanilines: The catalytic effect of phosphonium-based ionic liquids
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At T ≥ 140 °C, different primary aromatic amines (pX-C 6H4NH2; X = H, OCH3, CH3, Cl) react with both ethylene- and propylene-carbonates to yield a chemoselective N-alkylation process: bis-N-(2-hydroxyalkyl)anilines [pX-C 6H4N(CH2CH(R)OH)2; R = H, CH 3] are the major products and the competitive formation of carbamates is substantially ruled out. At 140 °C, under solventless conditions, the model reaction of aniline with ethylene carbonate goes to completion by simply mixing stoichiometric amounts of the reagents. However, a class of phosphonium ionic liquids (PILs) such as tetraalkylphosphonium halides and tosylates turn out to be active organocatalysts for both aniline and other primary aromatic amines. A kinetic analysis monitored by 13C NMR spectroscopy, shows that bromide exchanged PILs are the most efficient systems, able to impart a more than 8-fold acceleration to the reaction. The reactions of propylene carbonate take place at a higher temperature than those of ethylene carbonate, and only in the presence of PIL catalysts. A mechanism based on the Lewis acidity of tetraalkylphosphonium cations and the nucleophilicity of halide anions has been proposed to account for both the reaction chemoselectivity and the function of the catalysts.
- Selva, Maurizio,Fabris, Massimo,Lucchini, Vittorio,Perosa, Alvise,Noe, Marco
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experimental part
p. 5187 - 5198
(2010/12/25)
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- A new one-pot, four-component synthesis of 1,2-amino alcohols: TiCl 3/t-BuOOH-mediated radical hydroxymethylation of imines
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(Chemical Equation Presented) An amine, an aldehyde, and methanol can be readily assembled in one pot under very mild conditions through a free-radical multicomponent reaction by using an aqueous acidic TiCl3/t-BuOOH system to afford 1,2-amino alcohols in fair to excellent yields.
- Clerici, Angelo,Ghilardi, Alessandra,Pastori, Nadia,Punta, Carlo,Porta, Ombretta
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supporting information; experimental part
p. 5063 - 5066
(2009/05/31)
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- Synthesis of β-amino alcohols from aromatic amines and alkylene carbonates using Na-Y zeolite catalyst
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A simple, efficient, and environmentally benign methodology for the synthesis of β-amino alcohols from aromatic amines and alkylene carbonates in the presence of the highly active and reusable solid base catalyst Na-Y zeolite is demonstrated. Georg Thieme Verlag Stuttgart.
- Shivarkar, Anandkumar B.,Gupte, Sunil P.,Chaudhari, Raghunath V.
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p. 1374 - 1378
(2007/10/03)
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- PYRIDINE AND RELATED LIGAND COMPOUNDS, FUNCTIONALIZED NANOPARTICULATE COMPOSITES AND METHODS OF PREPARATION
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Nanoparticulate composites and dispersion thereof using novel polymeric ligand compounds, in certain embodiments in conjunction with pyridinyl moieties coupling the nanoparticulate and ligand.
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- Inhibition of HIV integrase by 4-hydroxycoumarin dimer bearing aniline mustard moiety
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The design, synthesis of novel HIV-integrase (HIV-IN) inhibitors possessing the 4-hydroxycoumarin dimer bearing aniline mustard moiety are described. These compounds showed good inhibitory activity against HIV-IN.
- Mao, Pili Chih-Min,Mouscadet, Jean-Francois,Leh, Herve,Auclair, Christian,Hsu, Ling-Yih
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p. 1263 - 1270
(2007/10/03)
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- SYNTHESIS OF BAPTA-AM ANALOGUES CAPABLE OF ENHANCING THE VASCULAR PRODUCTION OF PROSTACYCLIN
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About 30 analogues of BAPTA-AM, a potential antithrombotic agent, have been synthesized and tested for their effect on the production of prostacyclin.None of them was found to be a better enhancher of the production of prostacyclin by aortic endothelial cells than BAPTA-AM itself.The enhancing effect can be produced by compounds unable to chelate Ca2+, thus confirming that it is not related to their buffering capacity for free Ca2+.
- Heilporn, S.,Broeders, F.,Daloze, D.,Braekman, J. C.,Boeynaems, J. M.
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p. 309 - 320
(2007/10/02)
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- Hypoxia-Selective Antitumor Agents. 3. Relationships between Structure and Cytotoxicity against Cultured Tumor Cells for Substituted N,N-Bis(2-chloroethyl)anilines
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A series of aniline mustards with a wide range of electron-donating and -withdrawing substituents in the 3- and 4-positions has been synthesized and evaluated for cytotoxicity in cell culture to examine the potential of using nitro group deactivated nitrogen mustards for the design of novel hypoxia-selective anticancer drugs (Denny, W.A.; Wilson, W.R.J.Med Chem. 1986, 29, 879).Hydrolytic half-lives in tissue culture media, determined by bioassay against a cell line (UV4) defective in the repair of DNA interstrand cross-links showed the expected dependence on the Hammett electronic parameter, ?, varying from 0.13 h for the 4-amino analogue to >100 h for analogues with strongly electron-withdrawing substituents.Cytotoxic potencies in aerobic UV4 cultures showed a similar dependence on ?.This dependence predicted that the 4-nitroaniline mustard would be 7200-fold less potent than its potential six-electron reduction product, the 4-amino compound, in growth inhibition assays using a 1-h drug exposure.The measured differential was much lower (225-fold) because of the instability of the latter compound, but a differential of 17500-fold was observed in the initial rate of killing by using a clonogenic assay.The potential for formation of reactive mustards by reduction to the amine or hydroxylamine was demonstrated by the 4-nitroso compound, which had an aerobic toxicity similar to that of the amine.Although these features confirmed the original rationale, the 3-nitro- and 4-nitroaniline mustards had only minimal hypoxic selectivity against UV cells.Toxicity to hypoxic cells appears to be limited by the low reduction potentials of these compounds and consequent lack of enzymatic nitroreduction.However, this study has demonstrated that nitro groups can be used to latentiate aromatic nitrogen mustards and indicates that examples with higher reduction potentials could provide useful hypoxia-selective therapeutic agents.
- Palmer, Brian D.,Wilson, William R.,Pullen, Susan M.,Denny, William A.
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p. 112 - 121
(2007/10/02)
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- Rubine disazo acid dyes for polyamides
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Dyes of the formula STR1 wherein B and D are each independently 1,4-phenylene or 1,4-naphthylene; M is hydrogen, lithium, sodium, potassium or ammonium; A1 is hydrogen, C1-4 alkoxy, C1-4 alkyl, trifluoromethyl, nitro, chloro, bromo, cyano, or hydroxy; B1 and B2 are each hydrogen, C1-3 alkoxy, C1-3 alkyl, chloro or bromo; D1 is hydrogen, C1-4 alkoxy, C1-4 alkyl, or chloro; D2 is hydrogen, C1-4 alkoxy, C1-4 alkyl, chloro, bromo, fluoro, or acylamino, acyl being C1-5 alkanoyl, C1-5 alkylsulfonyl, benzoyl or benzenesulfonyl, each acyl unsubstituted or substituted with 1 to 3 of C1-2 alkyl, C1-2 alkoxy, chloro, bromo, cyano, or hydroxy; and R1 and R2 are each C1-6 alkyl, C1-6 chloro or bromoalkyl, C2-6 hydroxy- or dihydroxyalkyl, C2-6 alkoxyalkyl, C1-6 cyanoalkyl, or phenyl-C1-2 alkyl (phenyl unsubstituted or substituted with 1 to 3 of C1-2 alkyl, C1-2 alkoxy, chloro, bromo, cyano or hydroxy) are useful in dyeing natural and synthetic polyamide fibers in deep and level shades of red to blue.
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