- To be dinuclear or not: Z-DNA induction by nickel complexes
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The left-handed Z-DNA has been identified as a gene regulating element. Therefore the generation of ZDNA through metal complexes might be an innovative way for the regulation of gene expression. Use of the new dinuclear complex N,N,N',N'-tetrakis-[2(3,5-dimethylpyrazol-l-yl)ethylJ-l,3propylenediamine- bis(nickel(II) dinitrate) (2) reversibly induced Z-DNA formation. However, when a 1:1 ratio of metal/dinucleating ligand was used as a control, the midpoint of the B- to Z-DNA transition was at the same nickel concentration as in case of the dinuclear complex. The novel mononuclear analogue, N-methyl-N,N-bis-[2(3,5- dimethylpyrazol-l-yl)ethyl]aminenickel(II)-dinitrate (3) was inducing the Z-DNA at a similar ratio versus nucleotides as free nickel(II) itself. For the first time, proton and nickel binding constants for the bis-[2-(pyrazol-lyl)ethyl] amine ligand system are reported and discussed. Both nickel complexes 2 and 3 were structurally characterized by single crystal analysis. Furthermore, the synthesis of the two new ligands, N,N,N',N,'-tetrakis-[2-(3,5-dimethylpyrazol-l- yl)ethyl]-l,2-propylenediamine (4) and N-methyl-N,N-bis-[2(3,5-dimethylpyrazol- l-yl)ethyl]amine (5) is described. The two major synthetic pathways leading to polypyrazoyl amines in general are critically discussed with respect to yield, reproducibility and handling of the intermediates.
- Spingier, Bernhard,Antoni, Philipp M.
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- Preparation of 1-amino-4-methylpiperazine
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The selectivity of the formation of N-di(2-chloroethyl)methylamine in reactions with various chlorinating agents has been investigated and the optimum chlorinating agent has been found. 1-Amino-4-methylpiperazine has been obtained for the first time by the cyclization of N-di(2-chloroethyl)methylamine with aqueous hydrazine. A possible mechanism has been proposed for the cyclization reaction. 2004 Springer Science+Business Media, Inc.
- Kushakova,Chernobroviy,Kuznetsov,Garabadgiu
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- Synthesis, structure, spectra and redox of Cu(II) complexes of chelating bis(benzimidazole) - Thioether ligands as models for electron transfer blue copper proteins
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The tridentate ligand 1,5-bis(benzimidazol-2-yl)-3-thiapentane (L1) with N2S donor set forms the complex [Cu(L1)-(H2O)Cl]Cl 1a and the linear quadridentate ligand 1,8-bis(benzimidazol-2-yl)-3,6-dithiaoctane (L2) with N2S2 donor set forms the complexes [Cu(L2)](ClO4)2·2H2O 2a and [Cu(L2)(NO3)]NO3 2b. The linear pentadentate ligand 1,11-bis(pyrid-2-yl)-3,6,9-trithiaundecane (L3) with N2S3 donor set forms the complex [Cu(L3)](ClO4)2 3. The perchlorate complex [Cu(L4)](ClO4)2·2CH3CN 4 of the pentadentate ligand,N,N-bis(benzimidazol-2-ylmethylthioethyl)methyl-amine (L4) with N3S2 donor set has also been isolated. In 1a Cu(II) is coordinated to the two benzimidazole nitrogens and thioether sulfur of the ligand L1, a chloride ion and a water molecule. The coordination geometry around copper is intermediate between trigonal bipyramidal and square pyramidal geometries and is better described as trigonal bipyramidal distorted square based pyramidal (TBDSBP) with the sulfur and nitrogen atoms and the chloride ion in the equatorial positions and the oxygen of water in the apical position. The coordination geometry around copper(II) in 2b is best described as trigonal bipyramidal, with both the thioether sulfur atoms [Cu-S(1), 2.529(5) and Cu-S(2), 2.438(6) A] and one of the oxygen atoms of the nitrate ion [Cu-O(1), 2.066(13) A] constituting the trigonal plane and both the benzimidazole nitrogens [Cu-N, 1.985(14) and 1.953(13) A] occupying the axial positions. The bulky benzimidazole moieties of the ligand prevent the other nitrate ion from coordinating and favours trigonal bipyramidal geometry in spite of the presence of two six-membered chelate rings. In 4 the coordination plane of Cu(II) is comprised of two benzimidazole nitrogens, one thioether sulfur and N-methyl substituted amine nitrogen atom with the other thioether sulfur atom coordinated axially. The coordination geometry is best described as trigonal bipyramidal distorted square based pyramidal (TBDSBP). The ligand field and EPR spectra of 1a, 2a and 2b are consistent with trigonal bipyramidal geometry in the solid state, whereas two ligand field bands in solution and an axial EPR spectrum in frozen solution were observed suggesting a change in coordination geometry to a square-based one on dissolution. The complexes 3 and 4 exhibit only one ligand field band in the solid state and axial EPR spectrum consistent with a square based geometry. All the complexes exhibit an intense S(σ)→Cu(II) CT band in the range 330-380 nm and a high positive CuII/CuI redox potential.
- Vaidyanathan,Balamurugan,Sivagnanam,Palaniandavar
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- Synthesis and characterisation of ruthenium dihydrogen complexes and their reactivity towards B-H bonds
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In this paper the synthesis and characterisation of ruthenium dihydrogen complexes bearing rigid aliphatic PNP pincer-type ligands are described. As one result hydride complexes were synthesised in good to high yields by a one-pot direct hydrogenation reaction. As another finding the dihydrogen complex, stabilised with a N-Me group in the ligand frame, can be converted with dimethylamine borane into a rare σ-boron complex [RuH2(BH 3)(Me-PNP)] with rapid B-N decoupling. Additionally, we present the first mass spectrometric analysis of the synthesised σ-complexes via liquid injection field desorption/ionisation technique (LIFDI-MS).
- Choi, Jong-Hoo,Schloerer, Nils E.,Berger, Josefine,Prechtl, Martin H. G.
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- Mass spectral studies of silyl derivatives of partially hydrolyzed products of nitrogen mustards: Important markers of nitrogen mustard exposure
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Rationale: Nitrogen mustards (NMs) are vesicant class of chemical warfare agents. From the viewpoint of the Chemical Weapons Convention partially hydrolyzed products of nitrogen mustards (pHpNMs) are considered as important markers of nitrogen mustard exposure. The detection of pHpNMs from biological or environmental samples is highly useful for obtaining forensic evidence of exposure to NMs. Methods: Gas chromatography interfaced with tandem mass spectrometry (GC/MS/MS) is a widely used tool for the identification and sensitive detection of metabolites of NMs in complex matrices. The pHpNMs were derivatized using silylating agents as they are highly polar and non-amenable to GC. The mass spectral studies of these silyl derivatives of pHpNMs were performed using GC/MS/MS in both electron ionization (EI) and chemical ionization (CI) mode. Results: Various approaches have been proposed to assess the fragmentation pathways of the trimethylsilyl (TMS) and tert-butyldimethylsilyl (TBDMS) derivatives of pHpNMs. All the proposed fragmentation pathways were based on the product and/or precursor ion scanning of corresponding ions in both EI and CI mode. In the case of EI, most of the fragmentation pathways involved either α-cleavage or inductive cleavage. Conclusions: This is the first report on the MS study of the silyl derivatives of pHpNMs. The study of the two different derivatives of pHpNMs using both EI- and CI-MS provides a reliable, unambiguous identification of pHpNMs in complex environmental and biomedical matrices (such as plasma and urine) during any verification activities.
- Chandra, Buddhadeb,Sinha Roy, Kanchan,Shaik, Mahabul,Waghmare, Chandrakant,Palit, Meehir
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- TIN COMPOUND, TIN PRECURSOR COMPOUND FOR FORMING A TIN-CONTAINING LAYER, AND METHODS OF FORMING A THIN LAYER USING THE SAME
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A tin compound, a tin precursor compound for forming a tin-containing layer, and a method of forming a thin layer, the tin compound being represented by Formula 1: wherein R1, R2, R3, R4, R5, R6, and R7 are each independently hydrogen, a linear alkyl group having 1 to 4 carbon atoms, or a branched alkyl group having 3 or 4 carbon atoms.
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Paragraph 0034
(2020/08/05)
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- Rational design of an organocatalyst for peptide bond formation
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Amide bonds are ubiquitous in peptides, proteins, pharmaceuticals, and polymers. The formation of amide bonds is a straightforward process: amide bonds can be synthesized with relative ease because of the availability of efficient coupling agents. However, there is a substantive need for methods that do not require excess reagents. A catalyst that condenses amino acids could have an important impact by reducing the significant waste generated during peptide synthesis. We describe the rational design of a biomimetic catalyst that can efficiently couple amino acids featuring standard protecting groups. The catalyst design combines lessons learned from enzymes, peptide biosynthesis, and organocatalysts. Under optimized conditions, 5 mol % catalyst efficiently couples Fmoc amino acids without notable racemization. Importantly, we demonstrate that the catalyst is functional for the synthesis of oligopeptides on solid phase. This result is significant because it illustrates the potential of the catalyst to function on a substrate with a multitude of amide bonds, which may be expected to inhibit a hydrogen-bonding catalyst.
- Handoko,Satishkumar, Sakilam,Panigrahi, Nihar R.,Arora, Paramjit S.
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supporting information
p. 15977 - 15985
(2019/10/11)
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- Molecular Routes to Two-Dimensional Metal Dichalcogenides MX2 (M = Mo, W; X = S, Se)
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New synthetic access to two-dimensional transition metal dichalcogenides (TMDCs) is highly desired to exploit their extraordinary semiconducting and optoelectronic properties for practical applications. We introduce here an entirely novel class of molecular precursors, [MIV(XEtN(Me)EtX)2] (MIV = MoIV, WIV, X = S, Se), enabling chemical vapor deposition of TMDC thin films. Molybdenum and tungsten complexes of dianionic tridentate pincer-type ligands (HXEt)2NR (R = methyl, tert-butyl, phenyl) produced air-stable monomeric dichalcogenide complexes, [W(SEtN(Me)EtS)2] and [Mo(SEtN(Me)EtS)2], displaying W and Mo centers in an octahedral environment of 4 S and 2 N donor atoms. Owing to their remarkable volatility and clean thermal decomposition, both Mo and W complexes, when used in the chemical vapor deposition (CVD) process, produced crystalline MoS2 and WS2 thin films. X-ray diffraction analysis and atomic-scale imaging confirmed the phase purity and 2D structural characteristics of MoS2 and WS2 films. The new set of ligands presented in this work open ups convenient access to a scalable and precursor-based synthesis of 2D transition metal dichalcogenides.
- Brune, Veronika,Hegemann, Corinna,Mathur, Sanjay
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p. 9922 - 9934
(2019/08/26)
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- COMPOUNDS AND METHODS for the inhibition of HDAC
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Disclosed are compounds having the formula: wherein X1, X2, X3, R1, R2, R3, R4, Y, A, Z, L and n are as defined herein, and methods of making and using the same.
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Paragraph 0395-0396
(2015/11/24)
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- COMPOSITIONS AND METHODS FOR THE TREATMENT OF SEVERE PAIN
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The invention relates to the compounds of formula I or its pharmaceutical acceptable salts, as well as polymorphs, solvates, enantiomers, stereoisomers and hydrates thereof. The pharmaceutical compositions comprising an effective amount of compounds of formula I, and methods for the treatment of severe pain may be formulated for oral, buccal, rectal, topical, transdermal, transmucosal, intravenous, parenteral administration, syrup, or injection. Such compositions may be used to treatment of postoperative pain, cancer pain, kidney stones pain, fractures, local pain, chronic pain, chemotherapy induced pain, neuropathic pain, post herpetic neuralgia, neuralgia, motor neurone disease, diabetic neuropathy, postherpetic neuralgia, injury, post-operative pain, osteoarthritis, rheumatoid arthritis, multiple sclerosis, spinal cord injury, migraine, HIV related neuropathic pain, cancer pain and lower back pain.
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Paragraph 0109-0110
(2015/03/31)
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- ANTI-CANCER AGENTS
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Described herein are compounds that may be selectively activated to produce active anti-cancer agents in tumor cells. Also disclosed are pharmaceutical compositions comprising the compounds, and methods of treating cancer using the compounds.
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Paragraph 0397
(2013/03/26)
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- COMPOSITIONS AND METHODS FOR TREATMENT OF SEVERE PAIN
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Compounds or their pharmaceutical acceptable salts, as well as polymorphs, solvates, enantiomers, stereoisomers and hydrates thereof. The pharmaceutical compositions comprising an effective amount of compounds of formula (I), and methods for the treatment of severe pain may be formulated for oral, buccal, rectal, topical, transdermal, transmucosal, intravenous, parenteral administration, syrup, or injection. Such compositions may be used to treatment of postoperative pain, cancer pain, kidney stones pain, fractures, local pain, chronic pain, chemotherapy induced pain, neuropathic pain, post herpetic neuralgia, motor neurone disease, diabetic neuropathy, postherpetic neuralgia, injury, post-operative pain, osteoarthritis, rheumatoid arthritis, multiple sclerosis, spinal cord injury, migraine, HIV related neuropathic pain, cancer pain and lower back pain.
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Paragraph 0095; 0096
(2013/12/03)
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- A unique aliphatic tertiary amine chromophore: Fluorescence, polymer structure, and application in cell imaging
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Although photoluminescence of tertiary aliphatic amines has been extensively studied, the usage of this fundamental chromophore as a fluorescent probe for various applications has unfortunately not been realized because their uncommon fluorescence is easily quenched, and strong fluorescence has been observed only in vapor phase. The objective of this study is how to retain the strong fluorescence of tertiary amines in polymers. Tertiary amines as branching units of the hyperbranched poly(amine-ester) (HypET) display relatively strong fluorescence (Φ = 0.11-0.43). The linear polymers with tertiary amines in the backbone or as the side group are only very weakly fluorescent. The tertiary amine of HypET is easily oxidized under ambient conditions, and red-shifting of fluorescence for the oxidized products has been observed. The galactopyranose-modified HypET exhibits low cytotoxicity and bright cell imaging. Thus, this study opens a new route of synthesizing fluorescent materials for cell imaging, biosensing, and drug delivery.
- Sun, Miao,Hong, Chun-Yan,Pan, Cai-Yuan
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supporting information
p. 20581 - 20584
(2013/02/22)
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- Linear cationic click polymer for gene delivery: Synthesis, biocompatibility, and in Vitro Transfection
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Sixteen novel cationic click polymers (CPs) were parallelly synthesized via the conjugation of four alkyne- functionalized monomers to four azide-functionalized monomers by "click chemistry". The biocompatibility of CPs was evaluated by in vitro cytotoxicity (MTT assay, Hoechst/PI apoptosis/necrosis assay, and cell cycle analysis) and blood compatibility tests (hemolysis and erythrocyte aggregation). The experimental results showed that the kind of amine groups, charge density, and number of methylene or ethylene glycol groups brought about the effect on toxicity of CPs. Among all polymers, two polymers (B1 and B2) showed good biocompatibility, inducing neither apoptosis nor necrosis at the test concentration and low hemolysis ratio and erythrocyte aggregation. In particular, B1 and B2 exhibited the comparable transfection efficiency compared with PEI (25 kDa) but much lower cytotoxicity. These results suggested that the novel cationic CPs could be promising carriers for gene delivery.
- Gao, Yu,Chen, Lingli,Zhang, Zhiwen,Gu, Wangwen,Li, Yaping
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experimental part
p. 3102 - 3111
(2011/10/08)
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- Study of electronic and vibronic contributions to cooperative enhancement of two-photon absorption in multibranched structures
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A series of multibranched benzylidene cyclopentanone dyes with non-conjugated central moiety were synthesized. Their one- and two-photon photophysical properties were systematically studied in comparison with corresponding triphenylamine derivatives. Electronic coupling and vibronic coupling contributions to cooperative enhancement of two-photon absorption in multibranched structure were revealed. The results showed that the crucial contribution for this enhancement was from electronic coupling effect among branches. In addition, no contribution of vibronic coupling was observed. Furthermore, multibranched effect on photosensitizing efficiency of these compounds was investigated by one-photon polymerization and the result indicated the electronic coupling effect was also beneficial to their photosensitizing efficiency. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2009.
- Xue, Jianqiang,Zhao, Yuxia,Wu, Jie,Wu, Feipeng,Fang, Xiangyun
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experimental part
p. 634 - 640
(2009/05/30)
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- SPIRO-PIPERIDINE DERIVATIVES
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The present invention is concerned with novel indol-2-yl-carbonyl-spiro-piperidine derivatives as V1a receptor antagonists, their manufacture, pharmaceutical compositions containing them and their use for the treatment of anxiety, depressive disorders and other diseases. The compounds of present invention are represented by the general formula (I) wherein R1 to R1, X and Y are as defined in the specification.
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Page/Page column 24
(2008/12/06)
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- SPIROPIPERIDINE DERIVATIVES
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The present invention is concerned with novel spiro-piperidine derivatives as V1a receptor antagonists, their manufacture, pharmaceutical compositions containing them and their use for the treatment of anxiety and depressive disorders and other diseases. The compounds of present invention are described with formula (I) wherein R1 to R5, R5′, R7 to R9, R7′, R8′, X and Y are as defined in the specification.
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Page/Page column 19-20
(2008/12/06)
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- Spiro-piperidine derivatives
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The present invention is concerned with novel spiro-piperidine derivatives as V1a receptor antagonists, their manufacture, pharmaceutical compositions containing them and their use as medicaments. The active compounds of the present invention are useful in the prevention and/or treatment of anxiety and depressive disorders and other diseases. In particular, the present invention is concerned with compounds of the general formula (I) wherein R1 to R5, R5′, X, Y and A are as defined in the specification.
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Page/Page column 14
(2008/12/06)
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- '3+1' Mixed-ligand oxotechnetium(V) complexes with affinity for melanoma: Synthesis and evaluation in vitro and in vivo
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'3+1' Mixed-ligand [99mTc]oxotechnetium complexes with affinity for melanoma were synthesized in a one-pot reaction. Complexation of technetium-99m with a mixture of N-R(3- azapentane-1,5-dithiol) [R = Me, Pr, Bn, Et2N(CH2)2] and N-(2- dialkylamino)ethanethiol [alkyl = X = Et, Bu, morpholinyl] using Sn2+ as the reducing agent resulted in the formation of '3+1' mixed-ligand technetium-99m complexes [TcO(SN(R)S)(SNX2)] in high radiochemical yield (60-98%). In vitro uptake studies in B16 murine melanoma cells indicated a moderate tumor-cell accumulation (40%) of compound 1 [R = Me, X = Et] and a higher accumulation (69%) of compound 2 [R = Me, X = Bu] after a 60-min incubation. In vivo evaluation of compounds 1-6 in the C57B16/B16 mouse melanoma model demonstrated tumor localization. Compound 2 displayed the highest accumulation with up to 5% ID/g at 60 min after injection. In vivo, 2 also showed a low blood-pool activity and high melanoma/spleen (4.3) and melanoma/lung (1.9) ratios at 1 h. These results suggest that small technetium-99m complexes could be useful as potential melanoma-imaging agents.
- Friebe, Matthias,Mahmood, Ashfaq,Spies, Hartmut,Berger, Ralf,Johannsen, Bernd,Mohammed, Ashour,Eisenhut, Michael,Bolzati, Cristina,Davison, Alan,Jones, Alun G.
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p. 2745 - 2752
(2007/10/03)
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- Crown Ether Annelated Tetrathiafulvalenes. 2
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A synthetic procedure leading to derivatives of tetrathiafulvalene (TTF) incorporating polyether chains of various lengths, some nitrogen analogs, and a 2,6-bis(methylene)pyridine analog has been developed.These compounds possess cage-type structures which were confirmed by X-ray crystallography in four cases, two of which are reported herein for the first time.Structural and electronic features of these cage molecules were correlated to oxidation potentials by the use of semiempirical methods (MNDO-PM3).An investigation of the alkali metal ion affinity using PDMS revealed that these compounds are poor ligands.Finally, in one case, protonation of the core TTF was studied by NMR.
- Hansen, T. K.,Joergensen, T.,Jensen, F.,Thygesen, P. H.,Christiansen, K.,et al.
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p. 1359 - 1366
(2007/10/02)
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