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F Kerek - One of the best experts on this subject based on the ideXlab platform.
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Characterization of the macrocyclic Carbon Suboxide factors as potent Na,K-ATPase and SR Ca-ATPase inhibitors.
Biochimica et biophysica acta, 2002Co-Authors: F Kerek, Robert Stimac, Hans-jürgen Apell, Frank Freudenmann, Luis MoroderAbstract:Recently discovered macrocyclic Carbon Suboxide (MCS) factors with the general formula (C3O2)n were found to strongly inhibit rabbit and rat Na,K-ATPase as well as SR Ca-ATPase. Highly active MCS factors were obtained by a base/acid treatment of their lipophilic precursor isolated from plants. In the ESI-MS spectra, the dominant molar mass ion of 431 Da corresponds to a 1:1 complex of the Carbon Suboxide hexamer (n=6;Mr=408 Da) with a Na + ion. Additional mass ions identified in positive and negative ion mode were assigned as complexes of the MCS hexamer (n=6) and octamer (n=8) with Na + or with TFA in various ratios. The dominant mass ion values of these active MCS factors from plants are also found in mass spectra of previously described endogenous digitalis-like factors (EDLF) from animals. This would suggest that ubiquitously distributed MCS factors may function as putative endogenous regulatory substances of Na,KATPase and possibly of other ATPases. With the symmetric display of several equivalent Carbonyl or hydroxy groups, the structure of MCS factors is particularly suited for interactions with proteins and other bio-molecules. This could explain the high biological activity and the unusual properties of the MCS factors. D 2002 Elsevier Science B.V. All rights reserved.
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The structure of the digitalislike and natriuretic factors identified as macrocyclic derivatives of the inorganic Carbon Suboxide.
Hypertension research : official journal of the Japanese Society of Hypertension, 2000Co-Authors: F KerekAbstract:The Natriuretic and Endogenous DigitalisLike Factors (EDLFs) are disclosed to be cyclomeric and macroring closed derivatives of the inorganic Carbon Suboxide. The macrocyclic cyclohexamer with six Carbon Suboxide units has a molar mass of 408.2 Da, as previously been found for the EDLF of animal origin. The anhydrous cyclohexameric factor is lipophilic but is transformed into more hydrophilic derivatives by the stepwise addition of water. Based on the present findings, it appears that EDLFs exist in solution as an equilibrium mixture of lipophilic and hydrophilic forms and not as a single chemical substance. This structural assumption better accounts for the earlier observed highly anomalous properties of EDLFs. The simultaneously found higher molar mass (4,100 and 4,900 Da) macrocyclic Carbon Suboxide derivatives are tentatively identified as the Natriuretic factors.
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The structure of the digitalislike and natriuretic factors identified as macrocyclic derivatives of the inorganic Carbon Suboxide.
Hypertension Research, 2000Co-Authors: F KerekAbstract:The Natriuretic and Endogenous Digitalislike Factors (EDLFs) are disclosed to be cyclomeric and macroring closed derivatives of the inorganic Carbon Suboxide. The macrocyclic cyclohexamer with six Carbon Suboxide units has a molar mass of 408.2 Da, as previously been found for the EDLF of animal origin. The anhydrous cyclohexameric factor is lipophilic but is transformed into more hydrophilic derivatives by the stepwise addition of water. Based on the present findings, it appears that EDLFs exist in solution as an equilibrium mixture of lipophilic and hydrophilic forms and not as a single chemical substance. This structural assumption better accounts for the earlier observed highly anomalous properties of EDLFs. The simultaneously found higher molar mass (4, 100 and 4, 900 Da) macrocyclic Carbon Suboxide derivatives are tentatively identified as the Natriuretic factors. (Hypertens Res 2000; 23 Suppl: S33-S38)
Luis Moroder - One of the best experts on this subject based on the ideXlab platform.
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Characterization of the macrocyclic Carbon Suboxide factors as potent Na,K-ATPase and SR Ca-ATPase inhibitors.
Biochimica et biophysica acta, 2002Co-Authors: F Kerek, Robert Stimac, Hans-jürgen Apell, Frank Freudenmann, Luis MoroderAbstract:Recently discovered macrocyclic Carbon Suboxide (MCS) factors with the general formula (C3O2)n were found to strongly inhibit rabbit and rat Na,K-ATPase as well as SR Ca-ATPase. Highly active MCS factors were obtained by a base/acid treatment of their lipophilic precursor isolated from plants. In the ESI-MS spectra, the dominant molar mass ion of 431 Da corresponds to a 1:1 complex of the Carbon Suboxide hexamer (n=6;Mr=408 Da) with a Na + ion. Additional mass ions identified in positive and negative ion mode were assigned as complexes of the MCS hexamer (n=6) and octamer (n=8) with Na + or with TFA in various ratios. The dominant mass ion values of these active MCS factors from plants are also found in mass spectra of previously described endogenous digitalis-like factors (EDLF) from animals. This would suggest that ubiquitously distributed MCS factors may function as putative endogenous regulatory substances of Na,KATPase and possibly of other ATPases. With the symmetric display of several equivalent Carbonyl or hydroxy groups, the structure of MCS factors is particularly suited for interactions with proteins and other bio-molecules. This could explain the high biological activity and the unusual properties of the MCS factors. D 2002 Elsevier Science B.V. All rights reserved.
Christof Schulz - One of the best experts on this subject based on the ideXlab platform.
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Experimental and modeling study of Carbon Suboxide decomposition behind reflected shock waves
Physical chemistry chemical physics : PCCP, 2011Co-Authors: M. Aghsaee, Steffen H. Dürrstein, Heidi Böhm, Mustapha Fikri, Christof SchulzAbstract:At temperatures between 1150 and 2000 K and pressures between 0.1 and 0.2 MPa, the thermal decomposition of Carbon Suboxide (C3O2) behind reflected shock waves was investigated with a high-repetition-rate time-of-flight mass spectrometer (HRR-TOF-MS) connected to the end flange of a shock tube enabling rapid repetitive (100 kHz) measurements of the gas-phase composition. Concentration–time profiles for C3O2 and CO were measured and compared to simulations based on an improved mechanism for C3O2 decomposition and Carbon cluster growth. In addition, relative concentrations of C atoms and C2 molecules were detected and related to model predictions. For temperatures up to 1800 K, satisfactory agreement between experimental data and calculations was obtained. At higher temperatures, measurements and simulations differed noticeably. The importance of C2 for the growth of Carbon clusters was confirmed.
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yrolysis of Carbon Suboxide (C3O2) behind reflected shock waves using a time-of-flight mass spectrometer coupled to a shock tube
2011Co-Authors: M. Aghsaee, Steffen H. Dürrstein, Heidi Böhm, Christof SchulzAbstract:In this study the process of soot particle formation after Carbon Suboxide (C3O2) pyrolysis behind reflected shock waves was investigated with a time-of-flight mass spectrometer (TOF-MS) that allows for rapid repetitive measurements (up to 150 kHz) coupled to the end flange of a shock tube. The thermal decomposition of Carbon Suboxide (C3O2), C3O2 ® 2 CO + C, has been investigated at temperatures between 1150 and 2200 K and pressures at 1 to 1.75 bar. Concentration-time-profiles for C3O2 and CO were measured during the pyrolysis of Carbon Suboxide. To rationalize the experimental data extensive modeling was performed based on previous mechanisms for C3O2 dissociation. In low temperature there is a good agreement between experimental data and model data both for C3O2 and CO. With increasing temperature (T > 1650 K) there is a noticeable difference between experimental and modeled data.
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Nanoparticle formation from supersaturated Carbon vapor generates by laser-photolysis of Carbon Suboxide
2005Co-Authors: Alexander Eremin, E. V. Gurentsov, Max Hofmann, Christof SchulzAbstract:Carbon nanoparticles were synthesized from the supersaturated Carbon vapor generated in the course of ArF-laser photolysis of Carbon Suboxide (C3O2). The process of Carbon nanoparticle growth was observed by time-resolved laser-induced incandescence (TR-LII) and final particles were analyzed by transmission electron microscopy (TEM). It was found that the particles grow up to the final size of 4-12 nm within 0.02-1 ms. The rate of particle growth and their final size depend on pressure, Carbon atom concentration, and bath gas composition. The comparison between the LII- and TEM-based particle sizes yields the information on the thermal energy accommodation coefficients for He, Ar, CO, and C3O2 molecules on Carbon particles. A simple model of Carbon vapor condensation is proposed.
Renato Lemus - One of the best experts on this subject based on the ideXlab platform.
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Unitary group approach for effective potentials in 2D systems: Application to Carbon Suboxide C3O2
Chemical Physics Letters, 2018Co-Authors: M. Rodriguez-arcos, Renato LemusAbstract:Abstract A U ( 3 ) algebraic approach is proposed to describe 2D systems for effective potentials. Our approach is based on the 2D vibron model where the addition of a scalar boson is introduced into the 2D harmonic oscillator space. As a crucial ingredient of our approach an algebraic realization of the coordinates and momenta is obtained. This feature provides the tools to obtain the algebraic representation of a 2D Hamiltonian in terms of similitude transformation of a diagonal matrix. As an application of our approach the rotation-bending energy levels of Carbon Suboxide C3O2 are described in good agreement with experimental data.
Luciano Pandolfo - One of the best experts on this subject based on the ideXlab platform.
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ion molecule reactions of c2h2n c2h4n and c3h4n ions from acetonitrile with neutral Carbon Suboxide
Rapid Communications in Mass Spectrometry, 1998Co-Authors: Olga Bortolini, Luciano Pandolfo, Carlo Tommaselli, Pietro TraldiAbstract:The gas phase ion/molecule reactions of the title ionic species with Carbon Suboxide have been studied by ion trap mass spectrometry and interpreted as the result of electrophilic addition of these ions on the electron-rich central Carbon of C3O2 followed by CO loss. © 1998 John Wiley & Sons, Ltd.
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Ion/molecule reactions of C2H2N+, C2H4N+ and C3H4N+ ions from acetonitrile with neutral Carbon Suboxide †
Rapid Communications in Mass Spectrometry, 1998Co-Authors: Olga Bortolini, Luciano Pandolfo, Carlo Tommaselli, Pietro TraldiAbstract:The gas phase ion/molecule reactions of the title ionic species with Carbon Suboxide have been studied by ion trap mass spectrometry and interpreted as the result of electrophilic addition of these ions on the electron-rich central Carbon of C3O2 followed by CO loss. © 1998 John Wiley & Sons, Ltd.
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reactivity of Carbon Suboxide toward as and p stabilized ylides crystal and molecular structure of ch2 c o c asph3 coome 2
Inorganica Chimica Acta, 1995Co-Authors: Luciano Pandolfo, Roberta Bertani, Giacomo Facchin, Livio Zanotto, Paolo Ganis, Giovanni Valle, Roberta SeragliaAbstract:Abstract The reactions of Carbon Suboxide, C3O2, with a series of stabilized triphenylarsoranes, Ph3As=CHX (X = CN, COOMe, COMe, COPh, COC6H4-p-OMe), yield two different kinds of cmpounds. When X = CN, COOMe the reaction proceeds in a 2:1 ratio (ylide: C3C2) yielding open-chain maloni bis-ylidic compounds (1a,b) whereas in the cases of X = COMe, COPh, COC6H4-p-OME only 1:1 cyclic zwitterionic compounds (2a-c) are obtained. The crystal structure of the bis-ylidic compound 1b has been determined. The crystalas are monoclinic, space group C2/c with a = 19.296(8), b = 10.179(5), c = 19.743(8) A , β = 97.3(1)°, Z = 4 . The molecular parameters are consistent with an important contribution of the dipolar form −OC=CAs+. Carbon Suboxide has been reactde also with Ph3P=CHX (X = COC6H4-p-OMe, COOMe) giving the cyclic zwitterionic compounds 3 when X = COC6H4-p-OME, whereas when X = COOMe a mixture of products has been obtained.
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Reactivity of Carbon Suboxide toward As and P stabilized ylides. Crystal and molecular structure of CH2{C(=O) [C(=AsPh3) (COOMe)]}2
Inorganica Chimica Acta, 1995Co-Authors: Luciano Pandolfo, Roberta Bertani, Giacomo Facchin, Livio Zanotto, Paolo Ganis, Giovanni Valle, Roberta SeragliaAbstract:Abstract The reactions of Carbon Suboxide, C3O2, with a series of stabilized triphenylarsoranes, Ph3As=CHX (X = CN, COOMe, COMe, COPh, COC6H4-p-OMe), yield two different kinds of cmpounds. When X = CN, COOMe the reaction proceeds in a 2:1 ratio (ylide: C3C2) yielding open-chain maloni bis-ylidic compounds (1a,b) whereas in the cases of X = COMe, COPh, COC6H4-p-OME only 1:1 cyclic zwitterionic compounds (2a-c) are obtained. The crystal structure of the bis-ylidic compound 1b has been determined. The crystalas are monoclinic, space group C2/c with a = 19.296(8), b = 10.179(5), c = 19.743(8) A , β = 97.3(1)°, Z = 4 . The molecular parameters are consistent with an important contribution of the dipolar form −OC=CAs+. Carbon Suboxide has been reactde also with Ph3P=CHX (X = COC6H4-p-OMe, COOMe) giving the cyclic zwitterionic compounds 3 when X = COC6H4-p-OME, whereas when X = COOMe a mixture of products has been obtained.
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the organometallic chemistry of Carbon Suboxide
Comments on Inorganic Chemistry, 1991Co-Authors: Gastone Paiaro, Luciano PandolfoAbstract:Abstract Carbon Suboxide, C3, O2, reacts with a great variety of organometallic compounds. With organo-silicon and aluminium compounds it reacts with the C˭O moiety, giving sililation and carboalumination reactions. Insertion reactions of C˭C are performed with compounds having M-H, M-OR, M-NR2, M-PR2 bonds (M ≠ Si, Al), giving mono-metal derivatives (ketenyl) or di-metal derivatives of acil groups (amides, esthers, phospides). The coordination of C˭O or C˭C to transition metal complexes, the formation of allenic compounds and the deCarbonylation reactions allow the synthesis of a series of particular metal derivatives (ketenyl, ketenylidene and Carbonyl complexes) which, in some cases, present a peculiar reactivity.