- Synthesis of Deuterated or Tritiated Glycine and Its Methyl Ester
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Abstract: Heating glycine (Gly) and methyl glycinate (GlyOCH3) supported on 5% Pd/C or 5% Pt/C in a deuterium or tritium gas atmosphere gave the isotope-labeled products. The experiments were carried out at 180°C for 10 min. The deuterium atom inclusion under these conditions averaged up to 1.8 atoms per molecule for Gly and up to 1.0 atom per molecule for GlyOCH3. The reaction with tritium gas gave labeled products with a specific radioactivity of 27–31 Ci/mmol for Gly and 18 Ci/mmol for GlyOCH3.
- Shevchenko,Andreeva,Nagaev, I. Yu.,Myasoedov
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- Perthamides C and D, two new potent anti-inflammatory cyclopeptides from a Solomon Lithistid sponge Theonella swinhoei
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Two new metabolites, perthamides C and D, have been isolated from the marine sponge Theonella swinhoei. Their structures were determined by interpretation of NMR and ESIMS data. All compounds exhibited in vivo potent anti-inflammatory activity. Biological
- Festa, Carmen,De Marino, Simona,Sepe, Valentina,Monti, Maria Chiara,Luciano, Paolo,D'Auria, Maria Valeria,Débitus, Cecile,Bucci, Mariarosaria,Vellecco, Valentina,Zampella, Angela
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- Purification and characterization of carbon-phosphorus bond-cleavage enzyme from glyphosate degrading pseudomonas putida T5
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An inducible, carbon-phosphorus bond-cleavage enzyme was purified from cells of Pseudomonas putida T5 grown on N-phosphonomethyl glycine. The native enzyme had a molecular mass of approximately 70 kD and upon sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), yielded a homogeneous protein band with an apparent molecular mass of about 70 kD. Activity of purified enzyme was increased by 627-fold compared to the crude extract and showed pH and temperature optima of approximately 7 and 30°C, respectively. The purified enzyme had an apparent Km and Vmax of 3.7 mM and 6.8 mM/min, respectively, for its sole substrate N-phosphonomethyl glycine. The enzyme was inhibited by phenylmethylsulfonyl fluoride (PMSF), indicating the presence of serine at the active site. The enzyme was not inhibited by SDS, suggesting the absence of disulfide linkage in the enzyme. The enzyme was found to be inhibited by most of the metals studied except Mg2+. Detergents studied also inhibited glyphosate acting as a carbon-phosphorus bond-cleavage enzyme. Thus initial characterization of the purified enzyme suggested that it could be used as a potential candidate for glyphosate bioremediation.
- Selvi, A. Arul,Manonmani
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- ES-242 derivatives and cycloheptapeptides from Cordyceps sp. strains BCC 16173 and BCC 16176
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Five new ES-242 analogues (1-5) were isolated together with nine known compounds (6-14) from the insect pathogenic fungus Cordyceps sp. BCC 16173. A closely related strain, BCC 16176, provided cordyheptapeptide A (15) and small amount of its new analogue, cordyheptapeptide B (16), along with known ES-242s. Structures of the new bioxanthracenes, 1-5, were determined to be 6′-O-desmethyl analogues of 6 (ES-242-4), 8, 9 (ES-242-2), 12, and 13, respectively, primarily by spectroscopic analyses. Cordyheptapeptide B (16) has an N-methyl-L-phenylalanine residue instead of the N-methyl-L-tyrosine in 15.
- Isaka, Masahiko,Srisanoh, Urarat,Lartpornmatulee, Nattapat,Boonruangprapa, Tanapong
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- D-Aspartate N-methyltransferase catalyzes biosynthesis of N-methyl-D-aspartate (NMDA), a well-known selective agonist of the NMDA receptor, in mice
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N-Methyl-D-aspartate (NMDA), which is a selective agonist for the NMDA receptor, has recently been shown to be present in various biological tissues. In mammals, the activity of D-aspartate N-methyltransferase (DDNMT), which produces NMDA from D-aspartate, has been detected only in homogenates prepared from rat tissues. Moreover, the enzymatic properties of DDNMT have been poorly studied and its molecular entity has not yet been identified. In this report, we show for the first time that the activity of DDNMT is present in mouse tissues and succeed in obtaining a partially purified enzyme preparation from a mouse tissue homogenate with a purification fold of 1900 or more, and have characterized the enzymatic activity of this preparation. The results indicate that DDNMT, which is highly specific for D-aspartate and is S-adenosyl-L-methionine-dependent, is a novel enzyme that clearly differs from the known methylamine-glutamate N-methyltransferase (EC 2.1.1.21) and glycine N-methyltransferase (EC 2.1.1.20).
- Shibata, Kimihiko,Imanishi, Daiki,Abe, Katsumasa,Suzuki, Masataka,Takahashi, Shouji,Kera, Yoshio
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- Unraveling Tetrazine-Triggered Bioorthogonal Elimination Enables Chemical Tools for Ultrafast Release and Universal Cleavage
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Recent developments in bond cleavage reactions have expanded the scope of bioorthogonal chemistry beyond click ligation and enabled new strategies for probe activation and therapeutic delivery. These applications, however, remain in their infancy, with fu
- Carlson, Jonathan C.T.,Mikula, Hannes,Weissleder, Ralph
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- Folate in demethylation: The crystal structure of the rat dimethylglycine dehydrogenase complexed with tetrahydrofolate
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Dimethylglycine dehydrogenase (DMGDH) is a mammalian mitochondrial enzyme which plays an important role in the utilization of methyl groups derived from choline. DMGDH is a flavin containing enzyme which catalyzes the oxidative demethylation of dimethylglycine in vitro with the formation of sarcosine (N-methylglycine), hydrogen peroxide and formaldehyde. DMGDH binds tetrahydrofolate (THF) in vivo, which serves as an acceptor of formaldehyde and in the cell the product of the reaction is 5,10-methylenetetrahydrofolate instead of formaldehyde. To gain insight into the mechanism of the reaction we solved the crystal structures of the recombinant mature and precursor forms of rat DMGDH and DMGDH-THF complexes. Both forms of DMGDH reveal similar kinetic parameters and have the same tertiary structure fold with two domains formed by N- and C-terminal halves of the protein. The active center is located in the N-terminal domain while the THF binding site is located in the C-terminal domain about 40 ? from the isoalloxazine ring of FAD. The folate binding site is connected with the enzyme active center via an intramolecular channel. This suggests the possible transfer of the intermediate imine of dimethylglycine from the active center to the bound THF where they could react producing a 5,10- methylenetetrahydrofolate. Based on the homology of the rat and human DMGDH the structural basis for the mechanism of inactivation of the human DMGDH by naturally occurring His109Arg mutation is proposed. 2014 Elsevier Inc. All rights reserved.
- Luka, Zigmund,Pakhomova, Svetlana,Loukachevitch, Lioudmila V.,Newcomer, Marcia E.,Wagner, Conrad
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- SATIVANINE-C: A CYCLOPEPTIDE ALKALOID FROM THE BARK OF ZIZYPHUS SATIVA
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From the bark of Zizyphus sativa a previously undescribed 13 membered cyclopeptide alkaloid, sativanine-C has been isolated.The structure of this new compound was elucidated by spectroscopic methods, its transformation product and by chemical degradation.Key Word Index - Zizyphus sativa; Rhamnaceae; cyclopeptide alkaloid; sativanine-C.
- Shah, A. H.,Pandey, V. B.,Eckhardt, G.,Tschesche, R.
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- The kinetics and mechanisms of gas phase elimination of the ethyl ester of amino acid hydrochlorides
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The kinetics of the gas phase elimination of the ethyl ester of four α-amino acid hydrochlorides have been examined over the temperature range of 339-451 °C and pressure range of 8-108 Torr. The reactions, in a static reaction system, are homogeneous, unimolecular, and follow a first-order rate law. The rate coefficient is expressed by the following Arrhenius equations: Glycine ethyl ester hydrochloride: log k1(sec-1) = (12.29 ±0.24) - (203.7 ±3.2) kJ mol-1 (2.303 RT)-1 Sarcosine ethyl ester hydrochloride: log k1 (sec-1) = (13.64 ±0.60) - (215.0 ±7.8) kJ mol-1 (2.303 RT) -1 DL-Alanine ethyl ester hydrochloride: log k1) (sec -1 = (12.49 ± 0.46) - (200.2 ±5.9) kJ mol-1 (2.303 RT) L-Phenylalanine ethyl ester hydrochloride log k1(sec -1) = (12.49 ±0.09)-(194.4. ±1.1)kJ mol-1 (2.303 RT)-1 The elimination of these amino ester hydrochlorides leads to the formation of the corresponding α-amino acid and ethylene. However, the amino acid intermediates, except sarcosine, under the condition of reaction temperatures, undergo an extremely rapid decarboxylation process. These results apparently support previous reported mechanistic consideration where α-amino acids decompose to the corresponding amines and CO2 gas. Copyright
- Chuchani, Gabriel,Herize, Armando,Dominguez, Rosa Maria,Rotinov, Alexandra,Tosta, Maria
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- Chemically reactive supramolecular hydrogel coupled with a signal amplification system for enhanced analyte sensitivity
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Multicomponent supramolecular hydrogels are constructed for sensitive, naked-eye detection of small-molecule biomarkers. A dendritic self-immolative molecule and the corresponding enzyme as a signal amplification system were stably embedded in a hydrogen peroxide (H2O2)-responsive supramolecular hydrogel (BPmoc-F3), together with other enzymes. The nanostructure and mechanical strength of the hybrid BPmoc-F3 gel were not substantially diminished by incorporation of these multiple components in the absence of target biomarkers, but could be destroyed by addition of the biomarker through the multiple enzymatic and chemical cascade reactions operating in combination within the gel matrix. The sensitivity to biomarkers such as H2O2, glucose, and uric acid, detected by gel-sol transition, was significantly enhanced by the signal amplification system. An array chip consisting of these multicomponent hydrogels enabled the detection of the level of hyperuricemia disease in human plasma samples.
- Yoshii, Tatsuyuki,Onogi, Shoji,Shigemitsu, Hajime,Hamachi, Itaru
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- Mechanism of the primary stages of decomposition of aliphatic nitro- and fluoronitronitramines
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The primary stage of the decomposition of compounds RN(NO2)CH2C(NO2)2X is the homolytic cleavage of the C - NO2 bond, at X = NO2 and N - NO2 bond at X = F. The inductive effect of substituents decreases the dissociation energies of the C - N and N - N bonds by 1-2 kcal mol-1. Kinetic effects caused by the spatial interaction of groups and by stepwise decomposition of polyfunctional compounds are described.
- Korsounskii,Matveev,Nazina,Nazin
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- Acceptorless dehydrogenation of primary alcohols to carboxylic acids by self-supported NHC-Ru single-site catalysts
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The acceptorless dehydrogenation of diverse aromatic and aliphatic primary alcohols to corresponding carboxylic acids has been accomplished by self-supported NHC-Ru single-site catalysts under mild reaction conditions. Besides broad substrates with excellent activity, selectivity and good tolerance to sensitive functional groups, the solid single-site catalyst could be recovered and reused for more than 20 runs without deactivation. Remarkably, up to 1.8 × 104 turnover numbers could be achieved by this newly developed sustainable protocol in gram scale at low catalyst loading, highlighting its potential in industry.
- Yin, Shenxiang,Zheng, Qingshu,Chen, Jie,Tu, Tao
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p. 165 - 172
(2022/03/23)
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- A Cleavable C2-Symmetric trans-Cyclooctene Enables Fast and Complete Bioorthogonal Disassembly of Molecular Probes
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Bioorthogonal chemistry is bridging the divide between static chemical connectivity and the dynamic physiologic regulation of molecular state, enabling in situ transformations that drive multiple technologies. In spite of maturing mechanistic understanding and new bioorthogonal bond-cleavage reactions, the broader goal of molecular ON/OFF control has been limited by the inability of existing systems to achieve both fast (i.e., seconds to minutes, not hours) and complete (i.e., >99%) cleavage. To attain the stringent performance characteristics needed for high fidelity molecular inactivation, we have designed and synthesized a new C2-symmetric trans-cyclooctene linker (C2TCO) that exhibits excellent biological stability and can be rapidly and completely cleaved with functionalized alkyl-, aryl-, and H-tetrazines, irrespective of click orientation. By incorporation of C2TCO into fluorescent molecular probes, we demonstrate highly efficient extracellular and intracellular bioorthogonal disassembly via omnidirectional tetrazine-triggered cleavage.
- Carlson, Jonathan C. T.,Haider, Maximilian,Herrmann, Barbara,Klubnick, Jenna,Mikula, Hannes,Sohr, Barbara,Weissleder, Ralph,Wilkovitsch, Martin
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supporting information
p. 19132 - 19141
(2020/11/13)
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- POTENT AND SELECTIVE INHIBITORS OF NAV1.7
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Disclosed is a composition of matter comprising an isolated polypeptide, which is a peripherally-restricted Nav1.7 inhibitor. In some disclosed embodiments, the isolated polypeptide is an inhibitor of Nav1.7. Other embodiments are conjugated embodiments of the inventive composition of matter and pharmaceutical compositions containing the inventive composition of matter. Isolated nucleic acids encoding some embodiments of inventive polypeptides and expression vectors, and recombinant host cells containing them are disclosed. A method of treating or preventing pain is also disclosed.
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(2015/02/18)
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- FUNCTIONALIZED FLUORINE CONTAINING PHTHALOCYANINE MOLECULES
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Functionalized fluorine containing phthalocyanine molecules, methods of making, and methods of use in diagnostic applications and disease treatment are disclosed herein. In some embodiments, the fluorine containing phthalocyanine molecules are functionalized with a reactive functional group or at least one cancer-targeting ligand (CTL). The CTL can facilitate more efficient binding and/or internalization to a cancer cell than to a healthy cell. The CTL can inhibit expression of oncoprotein in some embodiments. The pthalocyanine moiety can be used in diagnostic applications, such as fluorescence labeling of a cancer cell, and/or treatment applications, such as catalyzing formation of a reactive oxygen species (ROS) which can contribute to cell death of a cancer cell.
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- PROCESS FOR PRODUCING SOLID AMINO ACID
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The problem to be solved by the present invention is to ea lily and efficiently produce an amino acid having 2 to 7 carbon atoms as a high-purity solid without complicated operation, which is useful as a synthetic intermediate for medicines or agrochemicals. The present invention is characterized in comprising a step of precipitating solid amino acid with high purity. In the present invention, the by-produced salt composed of the sulfonic acid and the amine was removed to the mother liquor by reacting an amine with a sulfonic acid salt of amino acid in an aprotic polar solvent, or by reacting a sulfonic acid with an amine salt of amino acid in an aprotic polar solvent. The sulfonic acid salt of amino acid, for example, may be produced by reacting a N-(tert-butoxycarbonyl) amino acid with a sulfonic acid, or by reacting an amino acid tert-butyl ester with a sulfonic acid.
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Paragraph 0055
(2014/12/09)
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- β-hairpin peptidomimetics
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β-Hairpin peptidomimetics of the general formula Cyclo(-Xaa1-Xaa2-Xaa3-Xaa4-Xaa5-Xaa6-Xaa7-Xaa8-Xaa9-Xaa10-Xaa11-Xaa12-Xaa13-Xaa14-Xaa15-Xaa16-), and pharmaceutically acceptable salts thereof, with Xaa 1-Xaa 16 being amino acid residues of certain types which are defined in the description and the claims, have CXCR4 antagonizing properties and prolonged half-lives in vivo and can be used for preventing HIV infections in healthy individuals or for slowing and halting viral progression in infected patients; or where cancer is mediated or resulting from CXCR4 receptor activity; or where immunological diseases are mediated or resulting from CXCR4 receptor activity; or for treating immunosuppression; or during apheresis collections of peripheral blood stem cells and/or as agents to induce mobilization of stem cells to regulate tissue repair. These peptidomimetics can be manufactured by a process which is based on a mixed solid- and solution phase synthetic strategy.
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- β-hairpin peptidomimetics
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β-Hairpin peptidomimetics of the general formula Cyclo(-Xaa1-Xaa2-Xaa3-Xaa4-Xaa5-Xaa6-Xaa7-Xaa8-Xaa9-Xaa10-Xaa11-Xaa12-Xaa13-Xaa14-), enantiomers and pharmaceutically acceptable salts thereof, with Xaa1-Xaa14 being amino acid residues of certain types which are defined in the description and the claims, have anti-infective activity, e.g. to selectively inhibit the growth of or to kill microorganisms such as Bacillus subtilis and/or Shigella boydii. They can be used as medicaments to treat or prevent infections or as disinfectants for foodstuffs, cosmetics, medicaments or other nutrient-containing materials. These peptidomimetics can be manufactured by a process which is based on a mixed solid- and solution phase synthetic strategy.
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- Meteorites as catalysts for prebiotic chemistry
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From outer space: Twelve meteorite specimens, representative of their major classes, catalyse the synthesis of nucleobases, carboxylic acids, aminoacids and low-molecular-weight compounds from formamide (see figure). Different chemical pathways are identified, the yields are high for a prebiotic process and the products come in rich and composite panels.
- Saladino, Raffaele,Botta, Giorgia,Delfino, Michela,Di Mauro, Ernesto
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p. 16916 - 16922
(2014/01/06)
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- 2-GUANIDINO-4-OXO-IMIDAZOLINE DERIVATIVES AS ANTIMALARIAL AGENTS, SYNTHESIS AND METHODS OF USE THEREOF
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The present invention relates to new 2-guanidino-4-oxo-imidazoline derivatives (deoxo-IZ), methods of making these compounds, compositions containing the same, and methods of using the same to prevent, treat, or inhibit malaria in a subject.
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(2012/11/13)
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- Synthesis and antimalarial activity of 2-guanidino-4-oxoimidazoline derivatives
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A series of 2-guanidino-4-oxoimidazoline (deoxo-IZ) derivatives was prepared and showed potent antimalarial activities in rodent and Rhesus models. Compound 8e, the most potent analogues of this series, is the first non-8-aminoqinoline antimalarial that demonstrated radical curative activity in non-human primate by oral route and showed causal prophylactic activity comparable to that of the commonly used clinical drugs in Rhesus monkeys infected with sporozoites of Plasmodium cynomolgi. The metabolic stability and metabolites profile indicated that the new deoxo-IZ derivatives (8) may act as prodrugs of the corresponding IZ (1 and 2) derivatives.
- Liu, Xianjun,Wang, Xihong,Li, Qigui,Kozar, Michael P.,Melendez, Victor,O Neil, Michael T.,Lin, Ai J.
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scheme or table
p. 4523 - 4535
(2011/09/15)
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- NOVEL MOLECULAR ASSEMBLY, MOLECULAR PROBE FOR MOLECULAR IMAGING AND MOLECULAR PROBE FOR DRUG DELIVERY SYSTEM USING THE SAME, AND MOLECULAR IMAGING SYSTEM AND DRUG DELIVERY SYSTEM
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The present invention provides a molecular assembly which is less likely to accumulate in tissue other than cancer tissue, is highly safe for a living body, and can be prepared by a simple and safe method and whose particle size can be easily controlled. The present invention provides a molecular imaging system and a molecular probe useful for the system, and a drug delivery system and a molecular probe useful for the system. The present invention provides a method for preparing molecular assembly, by which the particle size of molecular assembly having a signal group or a drug can be arbitrarily controlled in order to allow the molecular assembly to effectively accumulate in cancer tissue by utilizing EPR effect. A molecular assembly comprising: an amphiphilic block polymer A comprising a hydrophilic block chain and a hydrophobic block chain having 10 or more lactic acid units; a hydrophobic polymer A2 having at least 10 or more lactic acid units; and/or a labeled polymer B comprising at least 10 or more lactic acid units and a labeling group.
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- NOVEL MOLECULAR ASSEMBLY, MOLECULAR PROBE FOR MOLECULAR IMAGING AND MOLECULAR PROBE FOR DRUG DELIVERY SYSTEM USING THE SAME, AND MOLECULAR IMAGING SYSTEM AND DRUG DELIVERY SYSTEM
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The present invention provides a molecular assembly which is less likely to accumulate in tissue other than cancer tissue, is highly safe for a living body, and can be prepared by a simple and safe method and whose particle size can be easily controlled. The present invention provides a molecular imaging system and a molecular probe useful for the system, and a drug delivery system and a molecular probe useful for the system. The present invention provides a method for preparing molecular assembly, by which the particle size of molecular assembly having a signal group or a drug can be arbitrarily controlled in order to allow the molecular assembly to effectively accumulate in cancer tissue by utilizing EPR effect. A molecular assembly comprising: an amphiphilic block polymer A comprising a hydrophilic block chain and a hydrophobic block chain having 10 or more lactic acid units; a hydrophobic polymer A2 having at least 10 or more lactic acid units; and/or a labeled polymer B comprising at least 10 or more lactic acid units and a labeling group.
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- FLAVIN DERIVATIVES
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The present invention relates novel flavin derivatives and other flavin derivatives, their use and compositions for use as riboswitch ligands and/or anti-infectives. The invention also provides method of making novel flavin derivatives.
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(2010/04/03)
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- Fully enzymatic resolution of chiral amines: Acylation and deacylation in the presence of Candida antarctica lipase B
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A fully enzymatic methodology for the resolution of chiral amines has been demonstrated. Candida antarctica lipase B (CaLB)-catalyzed acylation with N-methyl-and N-phenylglycine, as well as analogues having the general formula R1-X-CH2CO2R2 (R1 = Me, Ph; X = O, S) afforded the corresponding enantioenriched amides, which were subsequently enzymatically hydrolyzed. Surprisingly, CaLB also proved to be the catalyst of choice for this latter step. The heteroatom in the acyl donor profoundly influences both the enzymatic acylation and deacylation; the O-substituted reagents performed best with regard to enantioselectivity as well as reaction rate in synthesis and hydrolysis.
- Ismail, Hilda,Lau, Rute Madeira,Van Rantwijk, Fred,Sheldon, Roger A.
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experimental part
p. 1511 - 1516
(2009/08/07)
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- Cell-permeable esters of diazeniumdiolate-based nitric oxide prodrugs
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(Chemical Equation Presented) Although 02-(2,4-dinitrophenyl) derivatives of diazeniumdiolate-based nitric oxide (NO) prodrugs bearing a free carboxylic acid group were activated by glutathione to release NO, these compounds were poor sources of intracellular NO and showed diminished antiproliferative activity against human leukemia HL-60 cells. The carboxylic acid esters of these prodrugs, however, were found to be superior sources of intracellular NO and potent inhibitors of HL-60 cell proliferation.
- Chakrapani, Harinath,Maciag, Anna E.,Citro, Michael L.,Keefer, Larry K.,Saavedra, Joseph E.
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supporting information; experimental part
p. 5155 - 5158
(2009/06/06)
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- Reductive methylation of primary and secondary amines and amino acids by aqueous formaldehyde and zinc
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Amines can be methylated when treated with formaldehyde and zinc in aqueous medium. Selective mono- or dimethylation can be achieved by proper choice of pH, stoichiometry and reaction time. This method can also be applied for amino acids.
- da Silva, Renato A.,Estevam, Idália H.S.,Bieber, Lothar W.
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p. 7680 - 7682
(2008/03/30)
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- Influence of solvent viscosity on the rate of hydrolysis of dipeptides by carboxypeptidase Y
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The influence of solvent viscosity on the rate of enzymatic hydrolysis of a series of dipeptides (Z-Phe-Gly, Z-Phe-Sar, Z-Phe-Ala, Z-Phe-NMeAla, Z-Phe-Aib and Z-Phe-Pro) by carboxypeptidase Y was investigated. The effect of solvent viscosity on the enzymatic hydrolysis revealed that whereas all Kcat values decreased with viscosity, those of the N-alkyl peptides decreased more than those of the N-H peptides. The kinetic behaviour implies the involvement of conformational changes of the enzyme in terms of the 'induced-fit' process. Copyright
- Kanosue, Yoshifumi,Kojima, Satoshi,Ohkata, Katsuo
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p. 448 - 457
(2007/10/03)
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- Relationship between the hydrophobicity of dipeptides and the Michaelis-Menten constant Km of their hydrolysis by carboxypeptidase-Y and carboxypeptidase-A
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The enzymatic hydrolysis of dipeptides by carboxypeptidase-Y and carboxypeptidase-A was investigated. In the enzymatic hydrolysis of the dipeptides, a good linear relationship (r = 0.997 and 0.999) was found between the Michaelis-Menten constant (Km) and the hydrophobicity of the substrates evaluated from relative elution volume in reversed-phase HPLC. The correlation suggests that the hydrophobicity of the C-terminal amino acid is a major factor in governing the stability of the enzyme-substrate complex. The difference in the slope of the linear-regression lines seems to reflect the degree of relative hydrophobicity of the binding pockets in carboxypeptidase-Y and carboxypeptidase-A.
- Kanosue, Yoshifumi,Kojima, Satoshi,Hiraga, Yoshikazu,Ohkata, Katsuo
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p. 1187 - 1193
(2007/10/03)
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- Preparation of N-acyl amino carboxylic acids, amino carboxylic acids and their derivatives by metal-catalyzed carboxymethylation in the presence of a promoter
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A process for the preparation of amino carboxylic acids, N-acyl amino carboxylic acids, or derivatives thereof by carboxymethylation of an amide, amide precursor or amide source compound in the presence of a carboxymethylation catalyst precursor and a promoter is provided. A carboxymethylation reaction mixture is formed by introducing a promoter, an amide, amide precursor or amide source compound, carbon monoxide, hydrogen, an aldehyde or aldehyde source compound, and a carboxymethylation catalyst precursor into a carboxymethylation reaction zone. In a preferred embodiment, the promoter is a supported noble metal promoter. In another preferred embodiment, the amide compound and aldehyde are selected to yield an N-acyl amino carboxylic acid which is readily converted to N-phosphonomethyl)glycine, or a salt or ester thereof.
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- Preparation of N-Z-protected N-methylated amino acids
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A process for preparing N-protected N-alkylated amino acids of the formula I: in which the substituents have the meanings stated in the description, comprises mixing a compound of the formula II with a solution of potassium tert-butanolate in a non-protic organic solvent, and subsequently adding a C1-2-alkyl halide.
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- Catalyst for dehydrogenating amino alcohols to aminocarboxylic acids or ethylene glycol (derivatives) to oxycarboxylic acids, process for its preparation and application thereof
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PCT No. PCT/EP97/05224 Sec. 371 Date Mar. 26, 1999 Sec. 102(e) Date Mar. 26, 1999 PCT Filed Sep. 24, 1997 PCT Pub. No. WO98/13140 PCT Pub. Date Apr. 2, 1998Catalyst for dehydrogenating amino alcohols to aminocarboxylic acids or ethylene glycol (derivatives) to oxycarboxylic acids, said catalyst containing zirconium, copper and possibly an additional metal, whereby the cited metals are precipitated as hydroxides, washed, dried, calcined, and reduced, preparable in that zirconium hydroxide is precipitated from an aqueous zirconium salt solution using a base until a pH of 4 to 10 is attained, the aqueous solution of a copper salt and possibly of an additional salt is added to the zirconium hydroxide suspension, and by adding further base copper hydroxide and possibly the hydroxide of the metal contained in the additional salt is precipitated until a pH of 8 to 14 is attained, the suspension obtained is filtered, washed, dried, calcined in air at 450 to 600 DEG C. for 2 to 4 hours and finally reduced at 200 to 250 DEG C. in a hydrogen stream for 2 to 4 hours.
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- Method of preparing amino carboxylic acids
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Process for the preparation of an N-acyl amino carboxylic acid by means of a carboxymethylation reaction. In this reaction, a reaction mixture is formed which contains a base pair, carbon monoxide, hydrogen and an aldehyde with the base pair comprising a carbamoyl compound and a carboxymethylation catalyst precursor. In a preferred embodiment, the carbamoyl compound and aldehyde are selected to yield an N-acyl amino carboxylic acid which is readily converted to N-(phosphonomethyl)glycine, or a salt or ester thereof.
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- Combinatorial libraries of substrate-bound cyclic organic compounds
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The invention relates to libraries of cyclic organic compounds and method of producing and assaying such libraries. According to the invention, each cyclic organic compound is constructed from a starting material in the form of a solid surface derivatized with a starting resin. Compounds are reacted with the resin to add or to form a cyclic group. The reactions are preferable carried out using a split resin procedure so that different compounds can be reacted with a plurality of subamounts so as to increase the size of the library. For example, compounds are reacted with a solid support bound starting resin to obtain a compound which includes an aldehyde functional group wherein the aldehyde compound or compounds reacted with it have substituents which are varied such that a mixture of products is obtained. The invention further relates to methods of producing combinatorial libraries of cyclic organic compounds from substrate bound compounds by cleaving the compounds from the support after synthesizing is completed and to assaying libraries of such compounds.
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- Peptides with an insulin-like action
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Peptides with an insulin-like action, of formula I: STR1 in which G is a hydrogen atom, an amino add residue, or a monosubstituted or polysubstituted amino acid; D is an amino acid residue, a phosphoamino acid residue, a monosaccharide residue, or a covalent bond; E is --NH--(CH2)n --NR52, a glycerol residue, or --NH--(CH2)p --R6 --R7 ; R1 is (C1 -C4)-alkyl or =O; R2 is a sulfhydryl protecting group, (C1 -C3)-alkyl, or a hydrogen atom; R3 and R4, independently of one another, are a hydrogen atom or methyl; R5, each being identical or different, is a hydrogen atom, 1 to 6 monosaccharide residues, or 1 to 6 monosubstituted or polysubstituted monosaccharide residues; R6 is O PO4 H, PO2 H, NHCOO, S or OCOO; R7 is a hydrogen atom, 1 to 6 monosaccharide residues, or 1 to 6 monosubstituted or polysubstituted monosaccharide residues; w is an integer 1 or 2; their preparation and use for treatment of diabetes mellitus or insulin-independent diabetes.
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- Synthesis and properties of carbamoyl derivatives of photolabile benzoins
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Carbamoyl derivatives of photolabile benzoins, particularly of 3',5'-dimethoxybenzoin, are readily prepared via the mixed p-nitrophenyl carbonate of the benzoin. The method is most suitable for secondary amines, since many primary amines exist in varying proportions as the cyclic In alkaline solution (0.2 M NaOH) the carbamates of unsymmetrical benzoins are readily equilibrated. Flash photolysis of 3',5'-dimethoxybenzoin carbamates generates the carbamate anion in a fast heterolytic process and liberation of the amine is controlled by the rate of decarboxylation.
- Papageorgiou, George,Corrie, John E.T.
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p. 3917 - 3932
(2007/10/03)
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- Disazo dyestuffs
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Disazo dyestuffs have been found which, in the form of the free acid, correspond to the formula (I) STR1 represents H or an optionally substituted aliphatic or aromatic radical and R1 to R6 and A have the meaning given in the description, which are outstandingly suitable for inkjet printing.
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- Preparation of N-protected N-alkylated amino acids
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A process for preparing N-protected N-alkylated amino acids of the formula STR1 where Rs and R1 -R3 have the meanings indicated in the description comprises adding a compound of the abovementioned formula where R3 is hydrogen to a solution of a base in a non-protic solvent and subsequently adding an alkylating agent.
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- Process for synthesis of FK-506 and tricarbonyl intermediates
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A process is described for the total synthesis of the macrolide immunosuppressant, FK-506, and important tricarbonyl process intermediates thereof. The tricarbonyl intermediates can be produced by the mild oxidation of 2,3-dihydroxy carboxylate compounds containing olefin moieties.
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- Triphendioxazine dyestuffs
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The novel triphendioxazine dyestuffs of the formula STR1 in which the substituents R, R', T1, T2, X, Y and n have the meanings given in the description are highly suitable for the dyeing and printing of cellulose-containing or amido-containing material.
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- Denitrosation of Nitrosamines - a Quantitative Study. Reactions of N-Methyl-N-nitrosoaniline, N-Nitrosoproline, Dimethylnitrosamine and Nitrososarcosine
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Rate measurements are reported for the denitrosation of N-methyl-N-nitrosoaniline (NMNA), N-nitrosoproline (NPr), dimethylnitrosamine (DMN), N-nitrososarcosine (NS) and N-nitrosopyrrolidine (NPy), in acid solution in the presence of nucleophilic catalysts in the following solvent systems: water, ethanol, various aqueous acetic acid solutions (up to 80percent acetic acid) and acetonitrile.The most reactive solvent system is 80percent acetic acid-water containing bromide ion (or thiourea) as a nucleophilic catalyst.The results, together with some earlier work in water, are discussed (a) in terms of the changing relative reactivities of the nucleophiles as the polarity of the solvent is changed, and (b) in terms of electron-withdrawing properties of any substituents which can effect both the protonation equilibria and also the rate constant for nucleophilic attack of the protonated form of the nitrosamine.
- Dix, Leslie R.,Oh, Shirlene M. N. Y. F.,Williams, D. Lyn H.
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p. 1099 - 1104
(2007/10/02)
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- A systematic entropy relationship for the general-base catalysis of the deprotonation of a carbon acid. A quantitative probe of transition-state solvation
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The general-base-catalyzed deprotonation of a carbon acid, the l-methyl-4-(phenylacetyl)pyridinium cation (pKa = 9.02 at 25 °C), has been investigated for 32 general-base catalysts (25 amines and seven phenoxide ions) in aqueous solution. Amines give a generally scattered Bronsted plot; ring-substituted benzylamines have ?= 0.52, and ring-substituted phenoxides have ?= 0.60, with the phenoxides being more reactive than amines of similar basicity. The temperature dependences of the general-base-catalyzed deprotonation of this carbon acid have been measured over the range 15-45 °C for 12 base catalysts (eight primary, secondary, and tertiary amines; 4-(dimethylamino)pyridine; two phenoxide ions; hydroxide ion). The entropies of activation for these deprotonations show a clean curvilinear dependence upon the entropies of protonation of these base species, with the hydroxide ion being the only significant deviant from this relationship. This observation quantitatively establishes the importance of solvation effects as the major source of deviations that are commonly observed in Bronsted relationships for general-base-catalyzed processes.
- Bunting, John W.,Stefanidis, Dimitrios
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p. 779 - 786
(2007/10/02)
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- Amine dealkylation process
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Amino acids can be produced from suitable tertiary and secondary amines by dealkylation using an alkali metal hydroxide.
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- Abiotic Synthesis of Amino Acids by Proton Irradiation of a Mixture of Carbon Monoxide, Nitrogen, and Water
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We have shown that proton irradiation simulating the action of cosmic rays and solar flare particles formed proteinous and non-proteinous amino acids such as glycine, alanine, aspartic acid and β-alanine from a mixture of carbon monoxide, carbon dioxide, nitrogen and water.The yield of amino acids per unit energy was the highest obtained among various prebiotic energy sources used.This result suggests the possibility of the formation of amino acids mildly reduced primitive atmospheres on the earth.
- Kobayashi, Kensei,Oshima, Tairo,Yanagawa, Hiroshi
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p. 1527 - 1530
(2007/10/02)
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- Fiber-reactive disazo brown dye having vinylsulfone-type reactive group
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A compound, or a salt thereof, represented by the following formula, STR1 wherein A is a substituted or unsubstituted phenylene or naphthylene group, B is STR2 in which R3 is a hydrogen atom or a lower alkyl, lower alkoxy, acylamino or ureido group, and R4 is a hydrogen atom or a lower alkyl or lower alkoxy group, R1 and R3 are independently a hydrogen atom or a substituted or unsubstituted lower alkyl group, X is a substituted or unsubstituted amino, lower alkoxy, substituted phenoxy or sulfo group, Y is --SO2 CH=CH2 or --SO2 CH2 CH2 Z, in which Z is a group capable of being split by the action of an alkali, and m is 2 or 3, which is useful for dyeing hydroxyl group- or amide group-containing fiber materials to give dyed products of a brown color having excellent fastness properties with good build-up property.
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- Anti-allergic compositions and their use
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Pharmaceutical compositions are described for anti-allergy therapy comprising an allergen or allergen extract, polysarcosine having an average molecular weight in the range of 2,000 to 12,000 and a chemical linking group connecting a reactive site on the polysarcosine to an amino group on the allergen or allergen extract, the reactive site on the polysarcosine being a H(CH3)N--, the allergen extract being an extract from an allergen selected from pollens, weeds, house dust mites and venoms, and the chemical linking group having the formula --CO--B--CO where B is a hydrocarbon chain of 1-4 carbon atoms. The disclosure also describes the analogous conjugates.
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- REACTION OF ATOMIC CARBON WITH AMMONIA. THE MECHANISM OF FORMATION OF AMINO ACID PRECURSORS.
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The reaction of arc-generated carbon atoms with ammonia have been investigated. Primary reactions of C//1 are NH insertion and hydrogen abstraction. The NH insertion leads to methyleneamine (1) and HCN. The hydrogen abstraction proceeds in a stepwise manner to generate CH//2, which reacts with NH//3 to produce CH//3NH//2. Hydrolysis of the nonvolatile residue from this reaction produces the amino acids glycine, alanine, N-methylglycine, beta -alanine, and aspartic acid. Serine is also formed when H//2O is included with the reactants. The mechanism of formation of the amino acid precursors is discussed. Labeling experiments (**2H and **1**3C) rule out a hydrogen cyanide polymer as a major precursor to the amino acids. These studies may provide information on extraterrestrial amino acids. Refs.
- Shevlin,McPherson,Melius
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p. 488 - 491
(2007/10/02)
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- Tumor-resolving and histolytic medicaments and their use
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Dehydrooligopeptides, some of which are known, demonstrate histolytic and tumor-resolving activity and may be used in medicaments causing the lysis of animal tissues and/or tumors in warm-blooded animals.
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