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Ivan Wichterle - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of the Carbonyl/Chlorine Interaction Parameters in Pentan-3-one-Chloroalkane Mixtures Using the Disquac Group Contribution Model
Collection of Czechoslovak Chemical Communications, 2020Co-Authors: Mariana Teodorescu, Ivan WichterleAbstract:Thermodynamic behaviour of the eight systems containing pentan-3-one and a Chloroalkane, namely 1-chlorobutane, 1,2-dichloroethane, 1,3-dichloropropane, 1,4-dichlorobutane, trichloromethane, 1,1,1-trichloroethane, tetrachloromethane and 1,1,2,2-tetrachloro- ethane was interpreted in terms of the DISQUAC group contribution model. It was found that quasichemical term for the contact C=O/Cl in the pentan-3-one-α,ω-diChloroalkane and pentan-3-one-1,1,1-trichloroethane systems is not negligible. The DISQUAC dispersive interchange parameters for C=O/Cl contact in these systems were evaluated from literature data on linear ketone + 1-Chloroalkane systems. It was found that the best description of experimental data for systems containing 1-chlorobutane, trichloromethane, tetrachloromethane, and 1,1,2,2-tetrachloroethane is provided using only dispersive contribution of the C=O/Cl contact. The vapour-liquid equilibrium, GE, and HE data were calculated using the DISQUAC model and compared with experimental data. The model provides a fairly consistent description. The relation between the DISQUAC interchange parameters for C=O/Cl contact and the Chloroalkane chain length was established.
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disquac characterization of the carbonyl chlorine interactions in binary mixtures of linear ketone with Chloroalkane
Collection of Czechoslovak Chemical Communications, 2003Co-Authors: Dana Dragoescu, Mariana Teodorescu, Alexandru Barhala, Ivan WichterleAbstract:Both the published and our new data on vapour-liquid equilibrium, excess Gibbs energy G E and excess enthalpy H E for the linear ketone-Chloroalkane binary mixtures are interpreted in terms of the DISQUAC group contribution model. The components are characterized by three types of contact surfaces: chlorine (Cl), carbonyl (C=O) and alkyl (CH 3 , CH 2 , CH, C). The Cl/alkyl and C=O/alkyl contact parameters are known from the literature. The parameters for C=O/Cl are re-evaluated here using extensive data on linear ketone-Chloroalkane mixtures. It was found that the best description of ketone mixtures with 1-Chloroalkane, trichloromethane, 1,1,1-trichloroethane, tetrachloromethane and 1,1,2,2-tetrachloroethane is obtained using a dispersive contribution of the C=O/Cl contact only. On the other hand the quasichemical term cannot be neglected for the ketone-α,ω-diChloroalkane systems. The newly evaluated interaction parameters for DISQUAC model enable good prediction of phase equilibrium and thermodynamic properties G E and H E as well as the temperature dependence of G E .
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Application of the Predictive UNIFAC Model to the Pentan‐3‐one/Chloroalkane and 5‐Chloro‐2‐pentanone/Hydrocarbon Binary Systems
Chemical Engineering & Technology, 2000Co-Authors: Mariana Teodorescu, Z. Wagner, Ivan WichterleAbstract:The predictive capability of the UNIFAC model by Fredenslund et al. (1977) using the last revised parameters of Hansen et al. (1991) was tested to describe the behavior of the binary systems of pentan-3-one + Chloroalkane and 5-chloro-2-pentanone + hydrocarbon in the range of 313.15–373.15 K at low or moderate pressures. The Chloroalkanes under study were 1,2-dichloroethane, 1,3-dichloropropane, 1,4-dichlorobutane, trichloromethane, 1,1,1-trichloroethane, and 1,1,2,2-tetrachloroethane; the hydrocarbons investigated were n-hexane, toluene, and ethylbenzene. The results obtained were compared with the experimental data on VLE and the excess Gibbs energy reported recently by Teodorescu et al. (1997, 1998). The best results in prediction were found for the system of pentan-3-one + 1,4-dichlorobutane with average deviation up to 0.0041 for the vapor-phase composition and up to 1.83 % in pressure. For the other systems of diChloroalkanes the deviations increase with decreasing size of Chloroalkane. For the systems of trichloro- or tetraChloroalkanes the deviations are larger than for diChloroalkanes in both vapor-phase composition and pressure. For the mixtures of 5-chloro-2-pentanone + hydrocarbon the best prediction was obtained for n-hexane (up to 0.0058 in the vapor-phase composition and 5.70 % in pressure). The best description of the excess Gibbs energy is given for 5-chloro-2-pentanone + n-hexane mixture.
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application of the predictive unifac model to the pentan 3 one Chloroalkane and 5 chloro 2 pentanone hydrocarbon binary systems
Chemical Engineering & Technology, 2000Co-Authors: Mariana Teodorescu, Z. Wagner, Ivan WichterleAbstract:The predictive capability of the UNIFAC model by Fredenslund et al. (1977) using the last revised parameters of Hansen et al. (1991) was tested to describe the behavior of the binary systems of pentan-3-one + Chloroalkane and 5-chloro-2-pentanone + hydrocarbon in the range of 313.15–373.15 K at low or moderate pressures. The Chloroalkanes under study were 1,2-dichloroethane, 1,3-dichloropropane, 1,4-dichlorobutane, trichloromethane, 1,1,1-trichloroethane, and 1,1,2,2-tetrachloroethane; the hydrocarbons investigated were n-hexane, toluene, and ethylbenzene. The results obtained were compared with the experimental data on VLE and the excess Gibbs energy reported recently by Teodorescu et al. (1997, 1998). The best results in prediction were found for the system of pentan-3-one + 1,4-dichlorobutane with average deviation up to 0.0041 for the vapor-phase composition and up to 1.83 % in pressure. For the other systems of diChloroalkanes the deviations increase with decreasing size of Chloroalkane. For the systems of trichloro- or tetraChloroalkanes the deviations are larger than for diChloroalkanes in both vapor-phase composition and pressure. For the mixtures of 5-chloro-2-pentanone + hydrocarbon the best prediction was obtained for n-hexane (up to 0.0058 in the vapor-phase composition and 5.70 % in pressure). The best description of the excess Gibbs energy is given for 5-chloro-2-pentanone + n-hexane mixture.
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Application of the predictive UNIFAC model to the pentan-3-one/Chloroalkane and 5-chloro-2-pentanone/hydrocarbon binary systems
Chemical Engineering & Technology, 2000Co-Authors: Mariana Teodorescu, Z. Wagner, Ivan WichterleAbstract:The predictive capability of the UNIFAC model by Fredenslund et al. (1977) using the last revised parameters of Hansen et al. (1991) was tested to describe the behavior of the binary systems of pentan-3-one + Chloroalkane and 5-chloro-2-pentanone + hydrocarbon in the range of 313.15–373.15 K at low or moderate pressures. The Chloroalkanes under study were 1,2-dichloroethane, 1,3-dichloropropane, 1,4-dichlorobutane, trichloromethane, 1,1,1-trichloroethane, and 1,1,2,2-tetrachloroethane; the hydrocarbons investigated were n-hexane, toluene, and ethylbenzene. The results obtained were compared with the experimental data on VLE and the excess Gibbs energy reported recently by Teodorescu et al. (1997, 1998). The best results in prediction were found for the system of pentan-3-one + 1,4-dichlorobutane with average deviation up to 0.0041 for the vapor-phase composition and up to 1.83 % in pressure. For the other systems of diChloroalkanes the deviations increase with decreasing size of Chloroalkane. For the systems of trichloro- or tetraChloroalkanes the deviations are larger than for diChloroalkanes in both vapor-phase composition and pressure. For the mixtures of 5-chloro-2-pentanone + hydrocarbon the best prediction was obtained for n-hexane (up to 0.0058 in the vapor-phase composition and 5.70 % in pressure). The best description of the excess Gibbs energy is given for 5-chloro-2-pentanone + n-hexane mixture.
Mariana Teodorescu - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of the Carbonyl/Chlorine Interaction Parameters in Pentan-3-one-Chloroalkane Mixtures Using the Disquac Group Contribution Model
Collection of Czechoslovak Chemical Communications, 2020Co-Authors: Mariana Teodorescu, Ivan WichterleAbstract:Thermodynamic behaviour of the eight systems containing pentan-3-one and a Chloroalkane, namely 1-chlorobutane, 1,2-dichloroethane, 1,3-dichloropropane, 1,4-dichlorobutane, trichloromethane, 1,1,1-trichloroethane, tetrachloromethane and 1,1,2,2-tetrachloro- ethane was interpreted in terms of the DISQUAC group contribution model. It was found that quasichemical term for the contact C=O/Cl in the pentan-3-one-α,ω-diChloroalkane and pentan-3-one-1,1,1-trichloroethane systems is not negligible. The DISQUAC dispersive interchange parameters for C=O/Cl contact in these systems were evaluated from literature data on linear ketone + 1-Chloroalkane systems. It was found that the best description of experimental data for systems containing 1-chlorobutane, trichloromethane, tetrachloromethane, and 1,1,2,2-tetrachloroethane is provided using only dispersive contribution of the C=O/Cl contact. The vapour-liquid equilibrium, GE, and HE data were calculated using the DISQUAC model and compared with experimental data. The model provides a fairly consistent description. The relation between the DISQUAC interchange parameters for C=O/Cl contact and the Chloroalkane chain length was established.
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Calorimetric study of the selected nitroalkane+Chloroalkane binary systems
Journal of Thermal Analysis and Calorimetry, 2014Co-Authors: Mariana Teodorescu, B. Marongiu, Sara Maxia, Alessandra Piras, Marianna Usula, Silvia PorceddaAbstract:Excess enthalpies, H ^E, at 298.15 K and atmospheric pressure determined for 12 binary liquid mixtures containing nitromethane or nitroethane+1-chlorobutane, +1-chloropentane, +1-chlorohexane, +1,2-dichloroethane, +1,3-dichloropropane, and +1,4-dichlorobutane by means of a flow 2277-LKB microcalorimeter, are reported on over composition range. The experimental results, along with the literature data on vapor–liquid equilibrium (VLE), excess Gibbs energies, G ^E, and activity coefficients at infinite dilution, $$ \gamma_{\text{i}}^{\infty } $$ γ i ∞ , are interpreted in terms of DISQUAC group contribution model. The systems are characterized by three types of contact surface: nitro (NO_2), chlorine (Cl), and alkyl (CH_3, CH_2). The interchange energy parameters of the alkyl/NO_2 and alkyl/Cl contacts were determined independently from the study of alkane+nitroalkane and alkane+Chloroalkane systems. The structure-dependent interchange parameters of the NO_2/Cl contact are reported in this work. The model provides a fairly consistent description of the VLE and of thermodynamic functions G ^E, H ^E, $$ \gamma_{\text{i}}^{\infty } $$ γ i ∞ , for all investigated mixtures.
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disquac characterization of the carbonyl chlorine interactions in binary mixtures of linear ketone with Chloroalkane
Collection of Czechoslovak Chemical Communications, 2003Co-Authors: Dana Dragoescu, Mariana Teodorescu, Alexandru Barhala, Ivan WichterleAbstract:Both the published and our new data on vapour-liquid equilibrium, excess Gibbs energy G E and excess enthalpy H E for the linear ketone-Chloroalkane binary mixtures are interpreted in terms of the DISQUAC group contribution model. The components are characterized by three types of contact surfaces: chlorine (Cl), carbonyl (C=O) and alkyl (CH 3 , CH 2 , CH, C). The Cl/alkyl and C=O/alkyl contact parameters are known from the literature. The parameters for C=O/Cl are re-evaluated here using extensive data on linear ketone-Chloroalkane mixtures. It was found that the best description of ketone mixtures with 1-Chloroalkane, trichloromethane, 1,1,1-trichloroethane, tetrachloromethane and 1,1,2,2-tetrachloroethane is obtained using a dispersive contribution of the C=O/Cl contact only. On the other hand the quasichemical term cannot be neglected for the ketone-α,ω-diChloroalkane systems. The newly evaluated interaction parameters for DISQUAC model enable good prediction of phase equilibrium and thermodynamic properties G E and H E as well as the temperature dependence of G E .
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Application of the Predictive UNIFAC Model to the Pentan‐3‐one/Chloroalkane and 5‐Chloro‐2‐pentanone/Hydrocarbon Binary Systems
Chemical Engineering & Technology, 2000Co-Authors: Mariana Teodorescu, Z. Wagner, Ivan WichterleAbstract:The predictive capability of the UNIFAC model by Fredenslund et al. (1977) using the last revised parameters of Hansen et al. (1991) was tested to describe the behavior of the binary systems of pentan-3-one + Chloroalkane and 5-chloro-2-pentanone + hydrocarbon in the range of 313.15–373.15 K at low or moderate pressures. The Chloroalkanes under study were 1,2-dichloroethane, 1,3-dichloropropane, 1,4-dichlorobutane, trichloromethane, 1,1,1-trichloroethane, and 1,1,2,2-tetrachloroethane; the hydrocarbons investigated were n-hexane, toluene, and ethylbenzene. The results obtained were compared with the experimental data on VLE and the excess Gibbs energy reported recently by Teodorescu et al. (1997, 1998). The best results in prediction were found for the system of pentan-3-one + 1,4-dichlorobutane with average deviation up to 0.0041 for the vapor-phase composition and up to 1.83 % in pressure. For the other systems of diChloroalkanes the deviations increase with decreasing size of Chloroalkane. For the systems of trichloro- or tetraChloroalkanes the deviations are larger than for diChloroalkanes in both vapor-phase composition and pressure. For the mixtures of 5-chloro-2-pentanone + hydrocarbon the best prediction was obtained for n-hexane (up to 0.0058 in the vapor-phase composition and 5.70 % in pressure). The best description of the excess Gibbs energy is given for 5-chloro-2-pentanone + n-hexane mixture.
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application of the predictive unifac model to the pentan 3 one Chloroalkane and 5 chloro 2 pentanone hydrocarbon binary systems
Chemical Engineering & Technology, 2000Co-Authors: Mariana Teodorescu, Z. Wagner, Ivan WichterleAbstract:The predictive capability of the UNIFAC model by Fredenslund et al. (1977) using the last revised parameters of Hansen et al. (1991) was tested to describe the behavior of the binary systems of pentan-3-one + Chloroalkane and 5-chloro-2-pentanone + hydrocarbon in the range of 313.15–373.15 K at low or moderate pressures. The Chloroalkanes under study were 1,2-dichloroethane, 1,3-dichloropropane, 1,4-dichlorobutane, trichloromethane, 1,1,1-trichloroethane, and 1,1,2,2-tetrachloroethane; the hydrocarbons investigated were n-hexane, toluene, and ethylbenzene. The results obtained were compared with the experimental data on VLE and the excess Gibbs energy reported recently by Teodorescu et al. (1997, 1998). The best results in prediction were found for the system of pentan-3-one + 1,4-dichlorobutane with average deviation up to 0.0041 for the vapor-phase composition and up to 1.83 % in pressure. For the other systems of diChloroalkanes the deviations increase with decreasing size of Chloroalkane. For the systems of trichloro- or tetraChloroalkanes the deviations are larger than for diChloroalkanes in both vapor-phase composition and pressure. For the mixtures of 5-chloro-2-pentanone + hydrocarbon the best prediction was obtained for n-hexane (up to 0.0058 in the vapor-phase composition and 5.70 % in pressure). The best description of the excess Gibbs energy is given for 5-chloro-2-pentanone + n-hexane mixture.
Lance P Encell - One of the best experts on this subject based on the ideXlab platform.
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improved deconvolution of protein targets for bioactive compounds using a palladium cleavable Chloroalkane capture tag
ACS Chemical Biology, 2016Co-Authors: Rachel Friedman Ohana, Sergiy Levin, Monika G Wood, Kris Zimmerman, Melanie Dart, Marie K Schwinn, Thomas A Kirkland, Robin Hurst, Tetsuo H Uyeda, Lance P EncellAbstract:The benefits provided by phenotypic screening of compound libraries are often countered by difficulties in identifying the underlying cellular targets. We recently described a new approach utilizing a Chloroalkane capture tag, which can be chemically attached to bioactive compounds to facilitate the isolation of their respective targets for subsequent identification by mass spectrometry. The tag minimally affects compound potency and membrane permeability, enabling target engagement inside cells. Effective enrichment of these targets is achieved through selectivity in both their rapid capture onto immobilized HaloTag and their subsequent release by competitive elution. Here, we describe a significant improvement to this method where selective elution was achieved through palladium-catalyzed cleavage of an allyl-carbamate linkage incorporated into the Chloroalkane capture tag. Selective tag cleavage provided robust release of captured targets exhibiting different modes of binding to the bioactive compound,...
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deciphering the cellular targets of bioactive compounds using a Chloroalkane capture tag
ACS Chemical Biology, 2015Co-Authors: Rachel Friedman Ohana, Sergiy Levin, Kris Zimmerman, Thomas A Kirkland, Robin Hurst, Tetsuo H Uyeda, Carolyn C Woodroofe, Paul Otto, Matthew B Robers, Lance P EncellAbstract:Phenotypic screening of compound libraries is a significant trend in drug discovery, yet success can be hindered by difficulties in identifying the underlying cellular targets. Current approaches rely on tethering bioactive compounds to a capture tag or surface to allow selective enrichment of interacting proteins for subsequent identification by mass spectrometry. Such methods are often constrained by ineffective capture of low affinity and low abundance targets. In addition, these methods are often not compatible with living cells and therefore cannot be used to verify the pharmacological activity of the tethered compounds. We have developed a novel Chloroalkane capture tag that minimally affects compound potency in cultured cells, allowing binding interactions with the targets to occur under conditions relevant to the desired cellular phenotype. Subsequent isolation of the interacting targets is achieved through rapid lysis and capture onto immobilized HaloTag protein. Exchanging the Chloroalkane tag f...
Rachel Friedman Ohana - One of the best experts on this subject based on the ideXlab platform.
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improved deconvolution of protein targets for bioactive compounds using a palladium cleavable Chloroalkane capture tag
ACS Chemical Biology, 2016Co-Authors: Rachel Friedman Ohana, Sergiy Levin, Monika G Wood, Kris Zimmerman, Melanie Dart, Marie K Schwinn, Thomas A Kirkland, Robin Hurst, Tetsuo H Uyeda, Lance P EncellAbstract:The benefits provided by phenotypic screening of compound libraries are often countered by difficulties in identifying the underlying cellular targets. We recently described a new approach utilizing a Chloroalkane capture tag, which can be chemically attached to bioactive compounds to facilitate the isolation of their respective targets for subsequent identification by mass spectrometry. The tag minimally affects compound potency and membrane permeability, enabling target engagement inside cells. Effective enrichment of these targets is achieved through selectivity in both their rapid capture onto immobilized HaloTag and their subsequent release by competitive elution. Here, we describe a significant improvement to this method where selective elution was achieved through palladium-catalyzed cleavage of an allyl-carbamate linkage incorporated into the Chloroalkane capture tag. Selective tag cleavage provided robust release of captured targets exhibiting different modes of binding to the bioactive compound,...
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deciphering the cellular targets of bioactive compounds using a Chloroalkane capture tag
ACS Chemical Biology, 2015Co-Authors: Rachel Friedman Ohana, Sergiy Levin, Kris Zimmerman, Thomas A Kirkland, Robin Hurst, Tetsuo H Uyeda, Carolyn C Woodroofe, Paul Otto, Matthew B Robers, Lance P EncellAbstract:Phenotypic screening of compound libraries is a significant trend in drug discovery, yet success can be hindered by difficulties in identifying the underlying cellular targets. Current approaches rely on tethering bioactive compounds to a capture tag or surface to allow selective enrichment of interacting proteins for subsequent identification by mass spectrometry. Such methods are often constrained by ineffective capture of low affinity and low abundance targets. In addition, these methods are often not compatible with living cells and therefore cannot be used to verify the pharmacological activity of the tethered compounds. We have developed a novel Chloroalkane capture tag that minimally affects compound potency in cultured cells, allowing binding interactions with the targets to occur under conditions relevant to the desired cellular phenotype. Subsequent isolation of the interacting targets is achieved through rapid lysis and capture onto immobilized HaloTag protein. Exchanging the Chloroalkane tag f...
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abstract 2003 investigating the cellular interactions of birb796 analogues using a novel Chloroalkane capture tag
Cancer Research, 2015Co-Authors: Rachel Friedman Ohana, Sergiy Levin, Thomas A Kirkland, Robin Hurst, Carolyn C Woodroofe, Paul Otto, Tetsuo Uyeda, Michael J Ford, Richard N Jones, Danette L DanielsAbstract:Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA Identifying the targets of a bioactive compound is often the rate limiting step toward understanding the molecular mechanism of drug action. Current approaches rely on linking the bioactive compound to a surface or an affinity handle, permitting selective capture of interacting proteins for identification by mass spectrometry. A major consideration with these methods is insuring that the chemical derivatization of the bioactive compound does not disrupt the binding interactions with the cellular targets. We have developed a method based on a novel Chloroalkane capture tag that minimally affects compound potency and cell permeability. This allows verification of the pharmacological activity of the modified compound, thus increasing the confidence in the biological relevance of captured proteins. In addition, by allowing the Chloroalkane-modified compound to bind the targets within living cells, the cellular architecture during the binding step is preserved and better represents the conditions that the unaltered compound would normally engage these targets. Following binding with the tagged compound in live cells, the cells are lysed and the chloroalkylated compound and its associated targets are rapidly captured onto immobilized HaloTag protein and then released by competitive elution. The identified targets are then validated for direct binding relationship with the bioactive compound by bioluminescence energy transfer. We tested this target capture/target validation work flow using the interaction of MAPK kinases with two allosteric kinase inhibitors (BIRB796 and a BIRB analog exhibiting 100-fold lower potency). RESULTS: Using the two BIRB-Chloroalkane derivatives to selectively enrich for targets from HEPG2 cells, we identified and validated multiple relevant MAPK kinases as well as additional off-targets. Interestingly, all the discovered off-targets bind purines. Kinase inhibitors such as BIRB796 which acts by binding to the kinase ATP binding site can interact in a similar manner with other purine binding proteins. Using bioluminescence energy transfer we interrogated the affinity and residence time of the two BIRB compounds to multiple MAPK kinases inside living cells. Our results indicates that the BIRB796 analog exhibits 30-1000 fold reduced affinity to multiple MAPK kinases as well as significant shorter residence time compared to BIRB796. Taken together these results indicate that our workflow can reveal the direct binding relationships between bioactive compounds and their cellular targets and contribute to further understanding of these interactions. Citation Format: Rachel Friedman Ohana, Robin Hurst, Thomas Kirkland, Carolyn Woodroofe, Sergiy Levin, Paul Otto, Tetsuo Uyeda, Michael Ford, Richard Jones, Danette Daniels, Marjeta Urh, Keith Wood. Investigating the cellular interactions of BIRB796 analogues using a novel Chloroalkane capture tag. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2003. doi:10.1158/1538-7445.AM2015-2003
A V Sapre - One of the best experts on this subject based on the ideXlab platform.
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photoinduced dissociative electron transfer det interactions in methoxycalixarene Chloroalkane systems
Chemical Physics Letters, 2003Co-Authors: Jyotirmayee Mohanty, Sandip K Nayak, Subrata Chattopadhyay, A V SapreAbstract:Abstract Fluorescence quenching of methoxycalixarenes (MOCX) by Chloroalkanes (CA) has been investigated in acetonitrile solutions. Observed quenching is attributed to photoinduced dissociative electron transfer (DET) interaction, which is supported by the characterization of the Cl − ions and by the radical scavenging experiments. Comparing the Cl − yields with different DET systems, it is inferred that both concerted and stepwise DET mechanisms operate simultaneously in MOCX–CA systems. A correlation of the quenching constants with the free-energy changes following a suitable DET theory supports the above inference.