- Verbascoside, synthetic derivatives and other glycosides from Argentinian native plant species as potential antitumoral agents
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A phytochemical study was performed on three native plant species from the central-western zone of Argentina: Buddleja cordobensis Grisebach, Baccharis salicina Torr. & A. Gray and Nepeta cataria L. We could obtain verbascoside (1) from B. cordobensis. From N. cataria, we could obtain 1, 5, 9-epi-deoxyloganic acid (2) L. Finally, we could isolate 2-β-(L-rhamnopyranosyl)-3-angeloyloxy-15-acetyloxy-7,13(14)-E-dien-ent-labdane (3) and 2-β-(L-rhamnopyranosyl)-3-α-angeloyloxy-15-hydroxy-7,13(14)-E-dien-ent-labdane (4) from B. salicina. Moreover, three derivatives from 1, and one semi-synthetic derivative from 2, were prepared. PCR reaction was used to analyse the activity against DNA polymerase and cell culture to determine cytotoxicity and antitumoral activity. Verbascoside (1) was strongly active in the nanomolar scale (IC50 = 356 nM) against DNA polymerization. Moreover, verbascoside was also strongly active in the nanomolar scale against human melanoma cell line (IC50 = 256 nM) and human colorectal cell line (IC50 = 320 nM). Furthermore, derivatives 6 and 7 were cytotoxic against both cancer cell lines.
- Garro, Hugo A.,Bruna-Haupt, Ezequiel,Cianchino, Valeria,Malizia, Florencia,Favier, Silvina,Menacho-Márquez, Mauricio,Cifuente, Diego,Fernández, Claudio O.,Pungitore, Carlos R.
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Read Online
- Reactivity of mono-halogen carbene radical anions (CHX-; X = F, Cl and Br) and the corresponding carbanions (CH2X-; X = Cl and Br) in the gas phase
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The gas-phase reactions of mono-halogen substituted carbene radical anions, CHX- (X = F, Cl and Br) and the corresponding carbanions, CH2X- (X = Cl and Br) with halomethanes and organic esters have been examined with the use of Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry. The chlorine and bromine containing (radical) anions react by SN2 substitution with the parent chloro- and bromo-methanes, whereas an SN2 and/or a BAC2 reaction occurs with the methyl ester of trifluoroacetic acid and dimethyl carbonate. The main features of the results are: (i) the SN2 substitution of a given carbene radical anion with CH3C1 or CH3Br is less efficient than this reaction of the corresponding carbanion, (ii) the radical anions react less efficiently with dimethyl carbonate than the carbanions, (iii) the SN2 substitution is less important for the radical anions than for the carbanions in the reactions with the two carbonyl compounds, (iv) for both types of ions, the BAC2 pathway becomes relatively more important as the halogen atom is changed from chlorine to bromine. These findings are discussed in terms of the thermodynamics of the overall processes in combination with considerations of the potential energy surfaces which can describe these gas-phase processes.
- Born, Monique,Ingemann, Steen,Nibbering, Nico M. M.
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Read Online
- Synthesis of ethyl 4,5-bis(diethoxyphosphorylmethyl)-3-furoate
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Preparative procedure for 4,5-bis(diethoxyphosphorylmethyl)-3-furoate from 4-chloromethyl-3-furoate is developed. It includes substitution of chlorine with iodine, phosphorylation by means of the Arbuzov reaction, chloromethylation of 4-(diethoxyphosphorylmethyl)-3-furoate in the position 5 of the furan ring, substitution of chlorine with iodine in the obtained chloromethyl derivative, and repeated phosphorylation with triethyl phosphite. It was found that ethyl 4-(diethoxyphosphorylmethyl)-5(chloromethyl)-3-furoate reacts with sodium diethyl phosphite by two pathways. Besides usual nucleophilic substitution leading to phosphonate, transfer of the reaction center in the position 2 of the furan ring takes place. The ambident diethylphosphite anion in this case reacts at the oxygen to give tertiary phosphite. The latter is oxidized with the air oxygen to form ethyl 2-(diethoxyphosphoryloxy)-4-(diethoxyphosphorylmethyl)-5-methyl-3-furoate. Unlike that analogous iodomethyl phosphonate is phosphorylated selectively under the conditions of the Arbuzov reaction.
- Pevzner
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Read Online
- The Ethyl Halides: Stable Neutral and Radical Cation Isomers where X = F, Cl, Br, I
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The following isomers of the ethyl halide molecular ions have all been shown to be stable species in the gas phase: +.; +.; (ΔH0f = 1012 kJ mol-1); +. (ΔH0f = 971 kJ mol-1); +.; +. (ΔH0f = 1058 kJ mol-1); +. (ΔH0f = 995 kJ mol-1) and +..Neutralization-reionization mass spectrometry, employing Xe as the electron transfer target gas and O2 as the target gas for reionization, indicated that the ylides CH3ClCH2 and CH3BrCH2 could not be generated by such means.However, the species CH3CHClH, CH2CH2ClH and CH2CH2BrH ( and posibly CH3CHBr ) were unambiguously identified.
- Blanchette, Marcia C.,Holmes, John L.,Lossing, F. P.
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Read Online
- Effects of Preferential Solvation and of Solvent-Solvent Interaction on the Rates of Nucleophilic Substitution involving Anions in Binary Mixed Solvents. Theoretical Approach
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Theoretical procedures for investigating rate constants and activation parameters measured in binary mixed solvents have been presented on the basis of the concept of ideal associated mixtures.In methanol+acetonitrile mixtures the behaviour of the rate constant and of activation parameters for the ethyl iodide plus bromide ion reaction were interpreted as resulting from the specific interaction of bromide ion with methanol.In methanol+NN-dimethylacetamide mixtures association complex formation between methanol and NN-dimethylacetamide makes a significant contribution to the activation parameters, and this factor must be taken into account in interpreting the observed rate behaviour.
- Kondo, Yasuhiko,Kusabayashi, Shigekazu
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Read Online
- Nucleophilic Substitution in Binary Mixed Solvents. Kinetics and Transfer Enthalpies of Anions in the Mixed Solvents Methanol+Propylene Carbonate and Methanol+N-methyl-2-pyrrolidone
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Rate constants and activation enthalpies for the reaction of ethyl iodide with bromide ion have been determined in two solvent mixtures, i.e., methanol+propylene carbonate and methanol+N-methyl-2-pyrrolidone mixtures.Heats of solution have also been determined for ethyl iodide, tetra-n-butylammonium-bromide, -perchlorate and -tetra-n-butylborate in the two solvent mixtures.Judging from these transfer enthalpies, perchlorate ion seems to be a pertinent model compound for the activated complex of the reaction.Single ion transfer enthalpies have been evaluated on the basis of the (n-Bu)4NB(n-Bu)4 assumption in the two solvent mixtures.Transfer enthalpy against composition profiles for perchlorate ion are similar in the two solvent mixtures, whereas for bromide ion the corresponding profiles are quite different in the two solvent mixtures, i.e., a sharp minimum was observed for the profile in MeOH+PC mixtures.From these observations and from other evidence, it is concluded that bromide ion solvation involves both electrostatic interactions and specific interactions between solute and solvents.Model calculation performed on the basis of the above views reproduce the bromide ion profile in MeOH+PC mixtures well.
- Yasuhiko, Kondo,Kazumi, Yuki,Takeshi, Yoshida,Niichiro, Tokura
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Read Online
- Process for desulpherization and hydrogen recovery
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A process for removing hydrogen sulfide from a sour gas stream is presented. The method oxidizes hydrogen sulfide to sulfuric acid by reducing aqueous bromine to hydrobromic acid in solution. The aqueous bromine solution does not react with hydrocarbon components common to natural gas including methane and ethane. This allows the process to both sweeten sour gas and convert its hydrogen sulfide content to sulfuric acid in a single step. In the present process, sulfuric acid is concentrated to eliminate its bromine content prior to being removed from the system, while the remaining hydrobromic acid solution is electrolyzed to regenerate aqueous bromine and produce hydrogen. Hydrobromic acid electrolysis requires less than half the energy required by water electrolysis and is an inherently flexible load that can shed or absorb excess power to balance supply and demand.
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- Synthesis and mass spectra of rearrangement bio-signature metabolites of anaerobic alkane degradation via fumarate addition
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Metabolite profiling in anaerobic alkane biodegradation plays an important role in revealing activation mechanisms. Apart from alkylsuccinates, which are considered to be the usual biomarkers via fumarate addition, the downstream metabolites of C-skeleton rearrangement can also be regarded as biomarkers. However, it is difficult to detect intermediate metabolites in both environmental samples and enrichment cultures, resulting in lacking direct evidence to prove the occurrence of fumarate addition pathway. In this work, a synthetic method of rearrangement metabolites was established. Four compounds, namely, propylmalonic acid, 2-(2-methylbutyl)malonic acid, 2-(2-methylpentyl)malonic acid and 2-(2-methyloctyl)malonic acid, were synthesized and determined by four derivatization approaches. Besides, their mass spectra were obtained. Four characteristic ions were observed at m/z 133 + 14n, 160 + 28n, 173 + 28n and [M - (45 + 14n)]+ (n = 0 and 2 for ethyl and n-butyl esters, respectively). For methyl esterification, mass spectral features were m/z 132, 145 and [M - 31]+, while for silylation, fragments were m/z 73, 147, 217, 248, 261 and [M - 15]+. These data provide basis on identification of potential rearrangement metabolites in anaerobic alkane biodegradation via fumarate addition.
- Chen, Jing,Zhou, Lei,Liu, Yi-Fan,Hou, Zhao-Wei,Li, Wei,Mbadinga, Serge Maurice,Zhou, Jing,Yang, Tao,Liu, Jin-Feng,Yang, Shi-Zhong,Wu, Xiao-Lin,Gu, Ji-Dong,Mu, Bo-Zhong
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- Halogen-Dependent Surface Confinement Governs Selective Alkane Functionalization to Olefins
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The product distribution in direct alkane functionalization by oxyhalogenation strongly depends on the halogen of choice. We demonstrate that the superior selectivity to olefins over an iron phosphate catalyst in oxychlorination is the consequence of a surface-confined reaction. By contrast, in oxybromination alkane activation follows a gas-phase radical-chain mechanism and yields a mixture of alkyl bromide, cracking, and combustion products. Surface-coverage analysis of the catalyst and identification of gas-phase radicals in operando mode are correlated to the catalytic performance by a multi-technique approach, which combines kinetic studies with advanced characterization techniques such as prompt-gamma activation analysis and photoelectron photoion coincidence spectroscopy. Rationalization of gas-phase and surface contributions by density functional theory reveals that the molecular level effects of chlorine are pivotal in determining the stark selectivity differences. These results provide strategies for unraveling detailed mechanisms within complex reaction networks.
- Zichittella, Guido,Scharfe, Matthias,Puértolas, Bego?a,Paunovi?, Vladimir,Hemberger, Patrick,Bodi, Andras,Szentmiklósi, László,López, Núria,Pérez-Ramírez, Javier
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supporting information
p. 5877 - 5881
(2019/02/20)
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- An Activated TiC–SiC Composite for Natural Gas Upgrading via Catalytic Oxyhalogenation
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Alkane oxyhalogenation has emerged as an attractive catalytic route for selective natural gas functionalization to important commodity chemicals, such as methyl halides or olefins. However, few systems have been shown to be active and selective in these reactions. Here, we identify a novel and highly efficient TiC–SiC composite for methane and ethane oxyhalogenation. Detailed characterization elucidates the kinetics and mechanism of the selective activation under reaction conditions to yield TiO2–TiC–SiC. This catalyst outperforms bulk TiO2, one of the best reported catalysts, reaching up to 85 % selectivity and up to 3 times higher titanium-specific space-time-yield of methyl halides or ethylene. This is attributed to the fact that the active TiO2 phase generated in situ is embedded in the thermally conductive SiC matrix, facilitating heat dissipation thus improving selectivity control.
- Zichittella, Guido,Puértolas, Bego?a,Siol, Sebastian,Paunovi?, Vladimir,Mitchell, Sharon,Pérez-Ramírez, Javier
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p. 1282 - 1290
(2018/02/09)
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- Reliably Regioselective Dialkyl Ether Cleavage with Mixed Boron Trihalides
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A protocol for the regioselective cleavage of unsymmetrical alkyl ethers to generate alkyl alcohol and alkyl bromide products is described. A mixture of trihaloboranes triggers this conversion and exhibits improved reactivity profiles (regioselectivity and yield) compared with BBr3 alone. Additionally, this procedure allows the efficient synthesis of (B-Cl) dialkyl boronate esters. There are limited methods to generate acyclic dialkoxyboryl chlorides, and these intermediates constitute important synthons in main-group chemistry.
- Atienza, Bren Jordan P.,Truong, Nam,Williams, Florence J.
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supporting information
p. 6332 - 6335
(2018/10/09)
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- Ion liquid in the application in the preparation of bromoethane
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The invention discloses application of an ionic liquid in bromoethane preparation, belonging to the fields of green chemistry and new materials. Under the action of the ionic liquid, hydrobromic acid and ethanol are subjected to substitution reaction; and after the reaction finishes, after-treatment is performed to obtain the bromoethane. The ionic liquid is composed of cations X and anions Y, wherein the cations are imidazole, pyridine, pyrrolidone and other cations containing nitrogen heterocyclic ring, and the anions are various functionalized anions with catalytic action. The ionic liquid is used for preparing the bromoethane, thereby avoiding using the traditional concentrated sulfuric acid, enhancing the reaction efficiency, avoiding generating waste acid and being beneficial to environmental protection. The ionic liquid can be recovered, and is a high-efficiency green synthesis means.
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Paragraph 0056-0060
(2017/05/02)
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- One-Step Synthesis of Substituted Benzofurans from ortho- Alkenylphenols via Palladium-Catalyzed C=H Functionalization
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A dehydrogenative oxygenation of C(sp2)=H bonds with intramolecular phenolic hydroxy groups has been developed, which provides a straightforward and concise access to structurally diversely benzofurans from ortho-alkenylphenols. The reaction is catalyzed by palladium on carbon (Pd/C) without any oxidants and sacrificing hydrogen acceptors.
- Yang, Dejun,Zhu, Yifei,Yang, Na,Jiang, Qiangqiang,Liu, Renhua
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supporting information
p. 1731 - 1735
(2016/06/09)
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- 2D Ultrafast HMBC 1H,31P: Obtaining mechanistic details on the Michaelis-Arbuzov reaction
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Ultrafast NMR spectroscopy (UF-NMR) can be used to monitor chemical reactions in real time and to provide insights into their mechanisms and the nature of the intermediates formed. Here, we have developed a 2D 1H,31P UF-HMBC method and the corresponding NMR experimental setup to enable the study of a Michaelis-Arbuzov reaction at two different temperatures, 25 and 70 °C. The specific reaction studied was between triethyl phosphite and benzyl bromide to produce diethylbenzyl phosphonate. Our results show that at 70 °C the reaction takes place directly, without the detection of an intermediate by 1H,31P UF-HMBC. In contrast, at 25 °C, using zinc bromide as a catalyst, our results show the formation of benzyltriethoxy phosphonium bromide as an intermediate. The experiments again show the power of UF-NMR in mechanistic studies of reactions involving various phosphorus chemical species.
- Fernández-Valle, María Encarnación,Martínez-álvarez, Roberto,Molero-Vílchez, Dolores,Pardo, Zulay D.,Sáez-Barajas, Elena,Herrera, Antonio
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p. 799 - 805
(2015/03/05)
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- Reaction of α-carbanions of lithium acylates with 1,2-dibromoethane
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The reaction of 1,2-dibromoethane with α-carbanions of lithium acylates generated from acetic, butyric, isobutyric, and capronic acids with lithium diisopropylamide has been studied. Anion-radical and anionic pathways of the products formation have been discussed.
- Zorin,Zaynashev,Chanysheva,Zorin
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p. 1382 - 1385
(2015/08/03)
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- METHOD OF PRODUCING ALCOHOLS
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A method of making alcohols involves forming of alcohol esters from liquid alkane halides and a solution of metallic salts of organic acids to produce gaseous alcohol esters for reaction with magnesium or metal hydroxides to form the alcohol and the metal salt of the organic acids. In an improvement method, liquid phase alcohol esters instead of gaseous alcohol esters are produced from liquid alkane halides and a solution of metal salts of organic acids whose alkane esters are less soluble in water than that of the alkane halide and treating of the alcohol ester formed with magnesium or metal hydroxides to form the alcohol and the metal salt of the organic acids.
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Paragraph 0046
(2013/08/28)
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- One-pot new barbituric acid derivatives derived from the reaction of barbituric acids with BrCN and ketones
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Reaction of cyclic β-dicarbonyl compounds such as pyrimidine-(1 H,3H,5H)-2,4,6-trione (BA), 1,3-dimethyl pyrimidine-(1 H,3H,5H)-2,4,6-trione (DMBA) and 2-thioxo-pyrimidine-(1 H,3H,5H)-4,6-dione (TBA) with cyanogen bromide in acetone and 2-butanone in the presence of triethylamine afforded a new class of stable heterocyclic spiro[furo[2,3-d]pyrimidine-6,5′-pyrimidine]2, 2′,4,4′,6′(3H,3′H,5H)-penta-ones (dimeric forms of barbiturate) at 0 °C and ambient temperature. Structure elucidation was carried out by X-ray crystallographic, 1H NMR, 13C NMR, two dimensional NMR, FT-IR spectra, mass spectrometry and elemental analysis. The mechanism of product formation is discussed. The reaction of DMBA with cyanogen bromide in the presence of triethylamine also afforded trimeric form of barbiturate of uracil derivatives in good yield. The reaction of selected acyclic β-dicarbonyl compounds with cyanogen bromide in the presence of triethylamine in acetone and/or diethyl ether has also been investigated under the same condition. Diethyl malonate and ethyl cyanoacetate brominated and also ethyl acetocetate both bro-minated and cyanated on active methylene via cyanogen bromide.
- Hosseini, Yaser,Rastgar, Saeed,Zerrin Heren,Orhan Büyükgüng?r,Pesyan, Nader Noroozi
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scheme or table
p. 309 - 318
(2011/11/06)
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- OXONIUM AND SULFONIUM SALTS
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The present invention relates to oxonium salts having [(Ro)3O]+ cations and sulfonium salts having [(Ro)3S]+ cations, where Ro denotes straight-chain or branched alkyl groups having 1-8 C atoms or phenyl which is unsubstituted or substituted by Ro, ORo, N(Ro)2, CN or halogen, and anions selected from the group of [PFx(CyF2y+1?zHz)6?x]? anions, where 2≦x≦5, 1≦y≦8 and 0≦z≦2y+1, or anions selected from the group of [BFn(CN)4?n]? anions, where n=0, 1 , 2 or 3, or anions selected from the group of [(Rf1SO2)2N]? anions or anions selected from the group of [BFwRf24?w]? anions, to processes for the preparation thereof, and to the use thereof, in particular for the preparation of ionic liquids.
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Page/Page column 11-12
(2009/03/07)
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- Sequestration, fluorometric detection, and mass spectroscopy analysis of lanthanide ions using surface modified magnetic microspheres for microfluidic manipulation
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Several methods for rapid sequestration, fluorometric detection, and the subsequent mass spectroscopic analysis of lanthanide ions using surface modified polystyrene magnetic microspheres are demonstrated. Mixed-ligand antenna complexes of Eu3+ in which one of the ligands is attached to the surface of the microspheres have been used as a means for the sequestration, immobilization, and detection of these ions. Using the ion-exchange properties of these microspheres, this scheme has been extended to the detection of nonluminescent ions. The principles of these assays form the basis for operation of a portable microfluidic device for general analytical and nuclear forensics applications and indicate the manner in which the established methods of analytical chemistry, such as liquid-liquid extraction and ion-exchange chromatography, can be adapted for such miniature devices.
- Shkrob, Ilya A.,Kaminski, Michael D.,Mertz, Carol J.,Rickert, Paul G.,Derzon, Mark S.,Rahimian, Kamyar
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supporting information; experimental part
p. 15705 - 15710
(2010/01/30)
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- Vapor generation of inorganic anionic species after aqueous phase alkylation with trialkyloxonium tetrafluoroborates
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Aqueous phase reaction of trialkyloxonium tetrafluoroborates, R 3O+BF4- (R=Me, Et) has been tested in the alkylation of simple inorganic anionic substrates such as halogen ions, cyanide, thiocyanate, sulphide an
- D'Ulivo, Alessandro,Pagliano, Enea,Onor, Massimo,Pitzalis, Emanuela,Zamboni, Roberto
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experimental part
p. 6399 - 6406
(2010/04/06)
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- Loss of benzene to generate an enolate anion by a site-specific double-hydrogen transfer during CID fragmentation of o-alkyl ethers of ortho-hydroxybenzoic acids
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Collision-induced dissociation of anions derived from orffco- alkyloxybenzoic acids provides a facile way of producing gaseous enolate anions. The alkyloxyphenyl anion produced after an initial loss of CO2 undergoes elimination of a benzene molecule by a double-hydrogen transfer mechanism, unique to the ortho isomer, to form an enolate anion. Deuterium labeling studies confirmed that the two hydrogen atoms transferred in the benzene loss originate from positions 1 and 2 of the alkyl chain. An initial transfer of a hydrogen atom from the C-l position forms a phenyl anion and a carbonyl compound, both of which remain closely associated as an ion/neutral complex. The complex breaks either directly to give the phenyl anion by eliminating the neutral carbonyl compound, or to form an enolate anion by transferring a hydrogen atom from the C-2 position and eliminating a benzene molecule in the process. The pronounced primary kinetic isotope effect observed when a deuterium atom is transferred from the C-l position, compared to the weak effect seen for the transfer from the C-2 position, indicates that the first transfer is the rate determining step. Quantum mechanical calculations showed that the neutral loss of benzene is a thermodynamically favorable process. Under the conditions used, only the spectra from ortho isomers showed peaks at mlz 77 for the phenyl anion and mlz 93 for the phenoxyl anion, in addition to that for the ortho-specific enolate anion. Under high collision energy, the ortho isomers also produce a peak at mlz 137 for an alkene loss. The spectra of meta and para compounds show a peak at mlz 92 for the distonic anion produced by the homolysis of the O-C bond. Moreover, a small peak at mlz 136 for a distonic anion originating from an alkyl radical loss allows the differentiation of para compounds from meta isomers. Copyright
- Attygalle, Athula B.,Bialecki, Jason B.,Nishshanka, Upul,Weisbecker, Carl S.,Ruzicka, Josef
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experimental part
p. 1224 - 1234
(2009/09/29)
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- N-alkylation of indole compounds in modified Wittig-Horner reaction
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N-Ethyl-3-styrylindoles are prepared under modified Wittig-Horner reaction conditions. Copyright Taylor & Francis Group, LLC.
- Singh, Anil K.,Asefa, Abera
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p. 1491 - 1494
(2008/02/02)
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- Catalytic cleavage of phosphate ester bonds by boron chelates
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Novel chemical compounds are disclosed having the general formula L{YXm}n, wherein X is selected from the Group 13 elements, Y is a halide, and L is a chelating ligand containing at least one binding atom contacting the Group 13 element, the atom being selected from the group consisting of C, N, O, and S, and m and n are integers having a value of at least 1. L may be a Schiff base type ligand, such as a salen ligand. The compositions of the present invention may be bidentate, quadridentate, or greater. The compositions may be used in dealkylation of phosphate esters or ethers. Advantageously, the methods of the present invention may be rendered catalytic.
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(2008/06/13)
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- Conjugated compounds based on vinylthiazole units
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Conjugated compounds based on vinylthiazole units show a strong polarization along the π chain, when NR2 groups as electron donors are attached in the terminal position. The effect can be even more enhanced by a CHO group as electron acceptor in the opposite terminal position. This property makes such oligomers (n = 1, 2, . . .) interesting for applications in linear and nonlinear optics.
- Meier, Herbert,Nicklas, Frank,Petermann, Ralf
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body text
p. 1525 - 1529
(2008/10/09)
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- Multicomponent synthesis of dihydropyrimidines and thiazines
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A broad range of differently substituted dihydropyrimidines and thiazines can be efficiently prepared by using a four-component reaction between phosphonates, nitriles, aldehydes, and iso(thio)cyanates. The scope and limitations of this multicomponent reaction are fully described. Variation of all four components has been investigated. The nitrile and aldehyde inputs can be varied extensively, but variation of the phosphonate input remains limited. An interesting rearrangement leading to phosphoramidates has been observed, Furthermore, the multicomponent reaction seems to be restricted to the use of isocyanates with strongly electron-withdrawing substituents, but an interesting additional exchange reaction under microwave conditions leads to dihydropyrimidines with less electron-withdrawing substituents at N3. In addition, a diastereoselective formation of dihydropyrimidines has been observed when using a chiral aldehyde as the input. Finally, by changing the isocyanate component to an isothiocyanate, thiazines are efficiently formed instead of the corresponding thio-dihydropyrimidines.
- Vugts, Danielle J.,Koningstein, Manoe M.,Schmitz, Rob F.,De Kanter, Frans J. J.,Groen, Marinus B.,Orru, Romano V. A.
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p. 7178 - 7189
(2007/10/03)
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- Synthesis of hydroxylated hydrocarbons
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Ethylene glycol, other diols, triols, and polyols are made in an efficient manner by reacting dibromides with water in the presence of a metal oxide. An integrated process of dibromide formation, alcohol synthesis, metal oxide regeneration, and bromine recycling is also provided.
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Page/Page column 5
(2008/06/13)
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- Aromatic methylidene compound, methylstyryl compound for producing the same, production method therefor, and organic electroluminescent element
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A compound of the formula (1): wherein R11 represents an alkyl group, an alkoxy group, a halogen atom, a cyano group, or a nitro group; n11 is an integer of 0 to 4; R21 and R31 are a hydrogen atom, an alkyl group, a cycloalkyl group, an aromatic group, or a heteroaromatic group; or R21 and R31 together form a condensed ring consisting of aromatic rings or heteroaromatic rings; and Ar is selected from the groups consisting of groups represented by the following formulae: and a methylstyryl compound for producing the same, the production methods thereof and an organic electroluminescent element having the compound.
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Page/Page column 55
(2008/06/13)
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- SEROTONINE REUPTAKE INHIBITOR
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There is provided a selective serotonin reuptake inhibitor having affinity for serotonin 1A receptors which comprises a cyclic amine represented by the formula: wherein G represents a formula (2): a prodrug of said cyclic amine, or a pharmaceutically acceptable salt of said cyclic amine or prodrug, as an active ingredient.
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- Carboxylic acids and the esters thereof, pharmaceutical compositions thereto and processes for the preparation thereof
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The present invention relates to carboxylic acids and esters of general formula wherein Ar, R, R1, X1, X3, X4, Y and Y1 are defined as in claim 1, the tautomers, the diastereomers, the enantiomers, the mixtures thereof and the salts thereof, particularly the physiologically acceptable salts thereof with inorganic or organic acids or bases, pharmaceutical compositions containing these compounds, the use thereof and processes for the preparation thereof, as well as the use thereof for the production and purification of antibodies and as labelled compounds in RIA and ELISA assays and as diagnostic or analytical aids in neurotransmitter research.
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- Use of organophosphorus compounds for the therapeutic and prophylactic treatment of infections
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Use of organophosphorus compounds of general Formula (I) for the therapeutic and prophylactic treatment of infections in humans and animals caused by viruses, fungi and parasites.
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Page column 13, 14
(2010/02/05)
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- N-alkylated thiazolium salts and process for their preparation
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The present invention relates to N-alkylated thiazolium salts, to a process for their preparation and also to their use as condensation and dehydrating agents.
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- Peptide and peptide mimetic conjugates with integrin-inhibitor properties
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The invention relates to compounds of formula (1) I-Q-X1, wherein B is bioactive cell adhesive mediating molecule. Q is absent or is an inorganic spacer molecule and X1 is an anchor molecule, selected from the group Lys.(CO—CH —(CH2)n—PO3H2)2(I)-Lys[-Lys-(CO—CH2—(CH2)a—PO3H2)2]2(ii) or -Lys-(Lys[-Lys-(CO—CH2—(CH2)n—PO3H2]2 (iii), and n independently represents 0, 1, 2 or 3, wherein a free amino group of group B is linked in peptide form to a free carboxyl group of the spacer molecule Q or of the anchor molecule X1 or a free amino group of the radical Q is linked in peptide form to a free carboxyl group of the radical X1. The invention also relates to the salts thereof. The inventive compounds can be used as integrin inhibitors for the treatment of illnesses, deficiencies, inflammations caused by implants and osteolytic illnesses such as osteoporosis, thrombosis, cardiac infarction and arteriosclerosis, in addition to the acceleration and strengthening of the integration process of implants or the biocompatible surface in tissue.
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- An integrated process for partial oxidation of alkanes
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The partial oxidation of alkanes via bromination followed by the reaction with solid metal oxide mixtures (MO) is shown to give an array of products that can be tuned by varying the MO and the reaction conditions.
- Zhou, Xiao-Ping,Yilmaz, Aysen,Yilmaz, Gurkan A.,Lorkovic, Ivan M.,Laverman, Leroy E.,Weiss, Michael,Sherman, Jeffrey H.,McFarland, Eric W.,Stucky, Galen D.,Ford, Peter C.
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p. 2294 - 2295
(2007/10/03)
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- Luminescent element material, luminescent element, ethylene derivative having n-containing 7-membered ring, and benzoazepine derivative
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Disclosed are a luminescent element material comprising a polymer having a partial structure represented by formula (I) and a luminescent element usin the same.
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- Vitamin D analogues
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Vitamin D compounds formula I wherein R represents hydrogen, or R represents (C1-C6)alkyl, phenyl, or (C7-C9)aralkyl, optionally substituted with one or more groups selected from (C1-C3)alkyl, F, phenyl; n is an integer having the value 0, 1, or 2; and X represents hydroxy or halogen.
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- Relative reactivity of methyl iodide to ethyl iodide in nucleophilic substitution reactions in acetonitrile and partial desolvation accompanying activation
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Through the examination of empirical correlations involving activation parameters for nucleophilic substitution of methyl iodide and of ethyl iodide, nucleophiles have been classified into three series: (1) nucleophiles with two equivalent reaction sites, (2) nucleophiles with a chlorine atom in the para-position, and (3) nucleophiles with a single reaction site. Three types of partial desolvation processes accompanying activation have been deduced on the basis of these classifications. A major factor determining the relative reactivity of methyl iodide to ethyl iodide in the substitution reaction of an anionic nucleophile having a single reaction site in acetonitrile (kMeI/kEtI) is suggested to be partial desolvation around the nucleophilic center on going from reactant to transition-state.
- Kondo, Yasuhiko,Urade, Miyuki,Yamanishi, Yukari,Chen, Xinyu
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p. 1449 - 1454
(2007/10/03)
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- Integrated process for synthesizing alcohols, ethers, and olefins from alkanes
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Alcohols, ethers, and olefins are manufactured from alkanes by mixing an alkane and bromine in a reactor to form alkyl bromide and hydrogen bromide. The alkyl bromide only or the alkyl bromide and the hydrogen bromide are directed into contact with metal oxide to form an alcohol and/or an ether, or an olefin and metal bromide. The metal bromide is oxidized to form original metal oxide and bromine, both of which are recycled.
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- Integrated process for synthesizing alcohols, ethers, and olefins from alkanes
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Alcohols, ethers, and olefins are manufactured from alkanes by mixing an alkane and bromine in a reactor to form alkyl bromide and hydrogen bromide. The alkyl bromide is directed into contact with metal oxide to form an alcohol and/or an ether, or an olefin and metal bromide. The metal bromide from the alkyl bromide metal oxide reaction is oxidized to form original metal oxide and bromine, both of which are recycled. The hydrogen bromide is separately directed into contact with metal oxide to form water and metal bromide. The metal bromide from the hydrogen bromide metal oxide is oxidized to form the original metal oxide which is recycled.
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- Integrated process for synthesizing alcohols, ethers, and olefins from alkanes
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Alcohols, ethers, and olefins are manufactured from alkanes by mixing an alkane and bromine in a reactor to form alkyl bromide and hydrogen bromide. The alkyl bromide only or the alkyl bromide and the hydrogen bromide are directed into contact with metal oxide to form an alcohol and/or an ether, or an olefin and metal bromide. The metal bromide is oxidized to form original metal oxide and bromine, both of which are recycled.
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- INTEGRATED PROCESS FOR SYNTHESIZING ALCOHOLS, ETHERS, AND OLEFINS FROM ALKANES
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Alcohols, ethers, and olefins are manufactured from alkanes by mixing an alkane and bromine in a reactor to form alkyl bromide and hydrogen bromide. The alkyl bromide only or the alkyl bromide and the hydrogen bromide are directed into contact with metal oxide to form an alcohol and/or an ether, or an olefin and metal bromide. The metal bromide is oxidized to form original metal oxide and bromine, both of which are recycled.
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- 2,3-oxidosqualene-lanosterol cyclase inhibitors
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The present invention relates to aminocyclohexanol derivatives useful for the treatment and/or prophylaxis of diseases which are associated with 2,3-oxidosqualene-lanosterol cyclase such as hypercholesterolemia, hyperlipemia, arteriosclerosis, vascular diseases, mycoses, gallstones, tumors and/or hyperproliferative disorders, and treatment and/or prophylaxis of impaired glucose tolerance and diabetes.
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- Synthesis of 2-γ-N-(aminoethyl)aminopropyl-2-methyl-6-alkyl(aryl,H)-1,3-dioxa-6- aza-2-silacyclooctanes
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Some new 2-γ-N-(aminoethyl)aminopropyl-2-methyl-1,3-dioxa-6-aza-2- silacyclooctane and 2-γ-N-(aminoethyl)aminopropyl-2-methyl-6-alkyl(aryl)-1,3-dioxa-6-aza- 2-silacyclooctanes have been synthesized from γ-chloropropyldimethoxymethyl silane by ethylenediamine substitution and diethanolamine or N-alkyl(aryl)diethanolamines substitution. The resulting silocanes have been characterized by elemental analyses, IR, and 1H NMR.
- Yang,Lin,Li
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p. 2817 - 2822
(2007/10/03)
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- Amine compounds, their production and use
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The present invention provides a compound of the formula: wherein Ar represents an aromatic group which may be substituted; X represents methylene, S, SO, SO2or CO; Y represents a spacer having a main chain of 2 to 5 atoms; n represents an integer of 1 to 5; i) R1and R2each represents a hydrogen atom or a lower alkyl which may be substituted, ii) R1and R2form, taken together with the adjacent nitrogen atom, a nitrogen-containing heterocyclic ring which may be substituted, or iii) R1or R2together with —(CH2)n—N═ form, bonded to a component atom of Ring B, a spiro-ring which may be substituted; Ring A represents an aromatic ring which may be substituted; Ring B represents a 4- to 7-membered nitrogen-containing non-aromatic ring which may be further substituted by alkyl or acyl, with a proviso that X represents S, SO, SO2or CO when Ring A has as a substituent a group represented by the formula: —NHCOR11 where R11represents alkyl, alkoxyalkyl, alkylthioalkyl, cycloalkyl, cycloalkylalkyl, aryl, arylalkyl or a group represented by the formula: —NHR12 where R12represents alkyl, cycloalkyl, cycloalkylalkyl, aryl or arylalkyl, or a salt thereof; which has an excellent somatostatin receptor binding inhibition action.
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- Reaction of triethyl phosphite with boron tribromide
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Reaction of boron tribromide with triethyl phosphite led to the formation of triethyl tribromoborophosphate 1, a complex bearing a P→B bond.
- Lewkowski, Jaroslaw,Mortier, Jacques,Vaultier, Michel
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p. 707 - 710
(2007/10/03)
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- Ester compounds
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An ester compound represented by the formula: wherein R is a hydrogen atom, a C1-C3 alkyl group unsubstituted or substituted with one or more halogen atoms, an allyl group unsubstituted or substituted with one or more halogen atoms, or a propargyl group unsubstituted or substituted with one or more halogen atoms; and X is a hydrogen atom, a halogen atom, a C1-C3 alkyl group unsubstituted or substituted with one or more halogen atoms, a C2-C3 alkenyl group unsubstituted or substituted with one or more halogen atoms, a C2-C3 alkynyl group unsubstituted or substituted with one or more halogen atoms, a C1-C3 alkoxy group unsubstituted or substituted with one or more halogen atoms, a C1-C3 alkylthio group unsubstituted or substituted with one or more halogen atoms, or a C1-C3 alkoxymethyl group containing a C1-C3 alkoxy group unsubstituted or substituted with one or more halogen atoms, has an excellent pest-controlling effect.
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- Process for the manufacture of bisphosphine oxide and bisphosphonate compounds
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A process for the manufacture of bisphosphine oxide compounds and bisphosphonates as intermediates for the production of bisphosphine ligands, in which in a single step process a) a phosphine oxide compound is reacted in an organic solvent at -70 DEG C. to 20 DEG C. with 0.5-3 eq. of a lithium or magnesium amide compound, b) 0.5-3 eq. of oxidatively-acting metal salt or metal salt complex are added to the suspension obtained in stage a) in a temperature range of -70 DEG C. to 20 DEG C., with a racemate of a bisphosphine oxide compound being obtained; c) a racemate cleavage is carried out if desired; and d) the bisphosphonates obtained in stage b) or c) are converted into bisphosphine oxides.
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- Study of activation energy and order of reaction of some liquid crystals
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Liquid crystals of the type p-phenylene-di-p-n-alkoxy benzoate have been prepared. Kissinger isothermal decomposition method has been used for determination of activation energy values of liquid crystals. Kissinger's assessment for shape index of DTA peaks is used to find the order of reaction. There is no direct relationship between the carbon atoms in terminal methylene groups and Ea values. Order of reaction value decreases with increase in heating rate upto carbon atoms 10 in the terminal methylene group but beyond this the order increases or decreases.
- Mundhe
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p. 246 - 249
(2007/10/03)
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- Alkoxyphenyl-substituted bisacylphosphine oxides
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Alkoxyphenyl-substituted bisacylphosphine oxides of the formula I STR1 in which R1 and R2 are identical or different and are a radical of the formula II STR2 n which R4 and R5 independently of one another are C1 -C12 alkyl or C1 -C12 alkoxy, R6, R7 and R8 independently of one another are hydrogen, C1 -C12 alkyl, C1 -C12 alkoxy or halogen, and R3 is a radical of the formula III STR3 in which R9 through R12 are hydrogen, halogen, alkyl or alkoxy, are suitable for the photopolymerization of compounds containing ethylenically unsaturated double bonds.
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- Kinetics of the synthesis of tetraethylethylenediphosphonate through NMR study
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The synthesis of tetraethylethylenediphosphonate (TEEDP) was investigated by means of 1H-NMR technique. The alkylenation process occurs via two steps. Some aspects of the reaction kinetics were discussed. The second step is ca. 1.7 times slower than the first one. TEEDP was synthesized via the intermediate formation of bromoethyl-diethylphosphonate. The first step is a 1st order reaction with respect to each reagent. Small TEEDP amounts were yielded in the first step suggesting the further reaction of the intermediate product with triethylphosphite. For both steps, the formation of the phosphonium ions (I and II) occurs more quickly than their decompositions.
- Azzouz, Abdelkrim,Didi, Mohamed-Amine
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p. 309 - 313
(2007/10/03)
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- The return of the succinimidyl radical
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The aqueous kinetics of the succinimidyl radical, S., has been re-examined in the presence of oxidizable substrates and oxygen. The results indicate a rapid equilibrium between S. and its ring-opened analogue, the β-(isocyanato-carbonyl)ethyl radical, PI.. The equilibrium constant K1 is ca. 10, with k1 ≈ 107 s-1 and k-1 ≈ 106 s-1. The glutarimidyl radical, G., was produced by one-electron reduction of N-chloroglutarimide, GCl. The rate constants of several oxidation and hydrogen abstraction reactions with S. and G. have been determined. Furthermore, halogen abstraction reactions from haloimides by some selected alkyl radicals were also scrutinised. Most striking is the finding that the 2-cyanoethyl radical abstracts Br from SBr ca. 25 times slower than does the ethyl radical. This demonstrates a strong β-effect and rationalises a relatively slow Br abstraction rate by PI. from SBr. While the closure rate of the PI' radical appears to be solvent-insensitive, the ring opening rate of S., k1, is estimated to be ca. 100 times faster in, e.g., CH2Cl2 than in water. This suggests hydrogen-bonded stabilisation of S.. Acta Chemica Scandinavica 1998.
- Merenyi, Gabor,Lind, Johan,Eberson, Lennart
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- Primary and secondary 5-(alkyloxy)thianthrenium perchlorates. Characterization with 1H NMR spectroscopy, reactions with iodide and bromide ion, and thermal decomposition in solution
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A series of 5-(alkyloxy)thianthrenium perchlorates has been made in which the alkyl group is primary (1a-1p) and secondary (2a-2g). Preparations were carded out by reaction of the corresponding alkanol with thianthrene cation radical perchlorate in CH2Cl2 solution followed by precipitation of the perchlorate salt with dry ether. 1H NMR spectroscopy reveals that the presence of a stereogenic center in the alkyl group causes inequivalence in the ordinarily paired protons (e.g., H-4, H-6) of the thianthrenium ring. Reaction of iodide and bromide ion with primary alkyl-group compounds (e.g., methyl, ethyl, propyl, butyl) gave the alkyl halide in very good yield and by a second-order kinetic displacement. The second product was thianthrene 5- oxide (ThO). Rate constants for some of these reactions are reported. Reaction of secondary alkyl group compounds (e.g., 2-propyl, 2-pentyl, 2- hexyl, and 3-hexyl) with iodide ion gave good yields of alkyl iodide but also increasing evidence for a side reaction at the sulfonium sulfur, leading to I2, thianthrene, and secondary alkanol. Decomposition of some compounds at 100°C in solution (acetonitrile or 1,2-dichloroethane) was studied and gave alkene(s) and ThO.
- Zhao, Wenyi,Shine, Henry J.
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p. 695 - 702
(2007/10/03)
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- Esterification of carboxylic acid salts
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Mono- or polycarboxylic acid esters are prepared by reacting a salt of such carboxylic acid with an organic halocompound, e.g., a (cyclo)alkyl, (cyclo)alkenyl, aryl or aralkyl halide, in an aqueous reaction medium, in the presence of a catalytically effective amount of a phase transfer catalyst, for example an onium salt.
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- Preparation of alkylesters of 0,0-dialkyl-4-phosphono-2-methyl-2-butenoic acid and alkyl esters of 4-halo-2-methyl-2-butenoic acid containing a high percentage of E isomers
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A process for the preparation of alkyl esters of 0,0-dialkyl-4-phosphono-2-methyl-2-butenoic acid containing a high percentage of E isomers, wherein the corresponding alkyl esters of 2-hydroxy-2-methyl-3-butenoic acid are caused to react with PBr3 or PCl3 at temperatures ranging from 0° to 80° C. in the absence of pyridine and, if desired, the resulting mixture comprising predominantly alkyl esters of 4-halo-2-methyl-2-butenoic acid is caused to react with trialkyl esters of phosphorous acid at temperatures ranging from 70° to 140° C. The end products are desirable C5 building blocks for polyene syntheses or preceding stages.
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