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Laura Catenacci - One of the best experts on this subject based on the ideXlab platform.

  • thermal studies of solvent exchange in isostructural solvates of a Tetroxoprim sulfametrole complex
    Journal of Thermal Analysis and Calorimetry, 2004
    Co-Authors: Giampiero Bettinetti, Mino R Caira, Milena Sorrenti, Laura Catenacci, M Ghirardi, Laszlo Fabian
    Abstract:

    Isostructural solvates of the 1:1 molecular complex between the antibacterial drugs Tetroxoprim (TXP) and sulfametrole (SMTR) with formulae TXP·SMTR·CH3OH (I), TXP·SMTR·C2H5OH (II) and TXP·SMTR·H2O (III), were investigated to establish their propensity for guest exchange. Separate exposure of powdered (I), (II) and (III) to a saturated atmosphere of each solvent of the complementary solvate pair at ambient temperature resulted in reversible solvent exchange in all cases. DSC and TG were the methods of choice for monitoring the exchange processes since (I)-(III) have distinct onset temperatures of desolvation and characteristic mass losses. Interpretation of the results in terms of the known locations of the solvent molecules in crystals of (I)-(III) led to the conclusion that solvent exchange probably proceeds by a co-operative mechanism involving material transport through channels while the common host framework is maintained.

  • order disorder enantiotropy monotropy and isostructurality in a Tetroxoprim sulfametrole 1 1 molecular complex crystallographic and thermal studies
    Journal of Pharmaceutical Sciences, 2003
    Co-Authors: Mino R Caira, Giampiero Bettinetti, Milena Sorrenti, Laura Catenacci
    Abstract:

    Abstract Two enantiotropic polymorphs of a Tetroxoprim (TXP)‐sulfametrole (SMTR) 1:1 molecular complex monohydrate and two isostructural TXP‐SMTR 1:1 molecular complex solvates with methanol and ethanol were grown and studied by X‐ray diffraction and thermal methods (thermogravimetric analysis and differential scanning calorimetry). Interconversion of the polymorphic hydrates is essentially an order/disorder transition involving a substituent on the TXP molecule. These hydrated phases may be described as “nearly isostructural” with the methanol and ethanol solvates. Thermal data for decomposition of the solvates were rationalized on the basis of the location and topologies of solvent crystallographic sites. Solid‐state properties of two monotropic polymorphs of the unsolvated TXP‐SMTR 1:1 molecular complex were also investigated and the theoretical and experimental phase diagrams of the individual components were assessed. The existence of polymorphic and pseudopolymorphic forms is determined by conformational flexibility of the TXP‐SMTR bimolecular complex components, a tendency for molecular disorder in TXP, the ability of the drug complex to form intricate, highly stabilized hydrogen‐bonded frameworks, and the competition between nonspecific van der Waals and specific hydrogen bond interactions. © 2003 Wiley‐Liss, Inc. and the American Pharmacists Association J Pharm Sci 92:2164–2176, 2003

Mino R Caira - One of the best experts on this subject based on the ideXlab platform.

  • thermal studies of solvent exchange in isostructural solvates of a Tetroxoprim sulfametrole complex
    Journal of Thermal Analysis and Calorimetry, 2004
    Co-Authors: Giampiero Bettinetti, Mino R Caira, Milena Sorrenti, Laura Catenacci, M Ghirardi, Laszlo Fabian
    Abstract:

    Isostructural solvates of the 1:1 molecular complex between the antibacterial drugs Tetroxoprim (TXP) and sulfametrole (SMTR) with formulae TXP·SMTR·CH3OH (I), TXP·SMTR·C2H5OH (II) and TXP·SMTR·H2O (III), were investigated to establish their propensity for guest exchange. Separate exposure of powdered (I), (II) and (III) to a saturated atmosphere of each solvent of the complementary solvate pair at ambient temperature resulted in reversible solvent exchange in all cases. DSC and TG were the methods of choice for monitoring the exchange processes since (I)-(III) have distinct onset temperatures of desolvation and characteristic mass losses. Interpretation of the results in terms of the known locations of the solvent molecules in crystals of (I)-(III) led to the conclusion that solvent exchange probably proceeds by a co-operative mechanism involving material transport through channels while the common host framework is maintained.

  • order disorder enantiotropy monotropy and isostructurality in a Tetroxoprim sulfametrole 1 1 molecular complex crystallographic and thermal studies
    Journal of Pharmaceutical Sciences, 2003
    Co-Authors: Mino R Caira, Giampiero Bettinetti, Milena Sorrenti, Laura Catenacci
    Abstract:

    Abstract Two enantiotropic polymorphs of a Tetroxoprim (TXP)‐sulfametrole (SMTR) 1:1 molecular complex monohydrate and two isostructural TXP‐SMTR 1:1 molecular complex solvates with methanol and ethanol were grown and studied by X‐ray diffraction and thermal methods (thermogravimetric analysis and differential scanning calorimetry). Interconversion of the polymorphic hydrates is essentially an order/disorder transition involving a substituent on the TXP molecule. These hydrated phases may be described as “nearly isostructural” with the methanol and ethanol solvates. Thermal data for decomposition of the solvates were rationalized on the basis of the location and topologies of solvent crystallographic sites. Solid‐state properties of two monotropic polymorphs of the unsolvated TXP‐SMTR 1:1 molecular complex were also investigated and the theoretical and experimental phase diagrams of the individual components were assessed. The existence of polymorphic and pseudopolymorphic forms is determined by conformational flexibility of the TXP‐SMTR bimolecular complex components, a tendency for molecular disorder in TXP, the ability of the drug complex to form intricate, highly stabilized hydrogen‐bonded frameworks, and the competition between nonspecific van der Waals and specific hydrogen bond interactions. © 2003 Wiley‐Liss, Inc. and the American Pharmacists Association J Pharm Sci 92:2164–2176, 2003

  • structural relationships thermal properties and physicochemical characterization of anhydrous and solvated crystalline forms of Tetroxoprim
    Journal of Pharmaceutical Sciences, 2002
    Co-Authors: Mino R Caira, Giampiero Bettinetti, Milena Sorrenti
    Abstract:

    Abstract Six distinct phases of the antibacterial Tetroxoprim (TXP) have been isolated by recrystallization from various solvents. These comprise two polymorphs, forms I and II, and four solvates with the following solvents and TXP solvent stoichiometric ratios: chloroform (3:2), water (3:2), methanol (2:1), and ethanol (2:1). Thermal and infrared spectral data showed that forms I and II are enantiotropically related with form II being stable below the transition temperature of 118°C and form I melting at 159°C. The crystal structure of form I contains three crystallographically independent TXP molecules arranged in layers formed by extensive base pairing between the 2,4‐diaminopyrimidine rings. This species invariably results upon heating the solvates of TXP. Thermogravimetry and differential scanning calorimetry respectively showed one‐step mass losses and progressively increasing desolvation temperatures for the solvates with chloroform, water, ethanol, and methanol. X‐ray diffraction studies revealed that the latter three solvates are isostructural, belonging to the class of “isolated site” solvates. Extensive base pairing maintains the common TXP crystalline framework. Thermal data for the desolvation of these phases are reconciled with the observed crystal packing features. Experimental and computed powder X‐ray patterns for form I and the solvates with water, methanol, and ethanol are presented.

Giampiero Bettinetti - One of the best experts on this subject based on the ideXlab platform.

  • thermal studies of solvent exchange in isostructural solvates of a Tetroxoprim sulfametrole complex
    Journal of Thermal Analysis and Calorimetry, 2004
    Co-Authors: Giampiero Bettinetti, Mino R Caira, Milena Sorrenti, Laura Catenacci, M Ghirardi, Laszlo Fabian
    Abstract:

    Isostructural solvates of the 1:1 molecular complex between the antibacterial drugs Tetroxoprim (TXP) and sulfametrole (SMTR) with formulae TXP·SMTR·CH3OH (I), TXP·SMTR·C2H5OH (II) and TXP·SMTR·H2O (III), were investigated to establish their propensity for guest exchange. Separate exposure of powdered (I), (II) and (III) to a saturated atmosphere of each solvent of the complementary solvate pair at ambient temperature resulted in reversible solvent exchange in all cases. DSC and TG were the methods of choice for monitoring the exchange processes since (I)-(III) have distinct onset temperatures of desolvation and characteristic mass losses. Interpretation of the results in terms of the known locations of the solvent molecules in crystals of (I)-(III) led to the conclusion that solvent exchange probably proceeds by a co-operative mechanism involving material transport through channels while the common host framework is maintained.

  • order disorder enantiotropy monotropy and isostructurality in a Tetroxoprim sulfametrole 1 1 molecular complex crystallographic and thermal studies
    Journal of Pharmaceutical Sciences, 2003
    Co-Authors: Mino R Caira, Giampiero Bettinetti, Milena Sorrenti, Laura Catenacci
    Abstract:

    Abstract Two enantiotropic polymorphs of a Tetroxoprim (TXP)‐sulfametrole (SMTR) 1:1 molecular complex monohydrate and two isostructural TXP‐SMTR 1:1 molecular complex solvates with methanol and ethanol were grown and studied by X‐ray diffraction and thermal methods (thermogravimetric analysis and differential scanning calorimetry). Interconversion of the polymorphic hydrates is essentially an order/disorder transition involving a substituent on the TXP molecule. These hydrated phases may be described as “nearly isostructural” with the methanol and ethanol solvates. Thermal data for decomposition of the solvates were rationalized on the basis of the location and topologies of solvent crystallographic sites. Solid‐state properties of two monotropic polymorphs of the unsolvated TXP‐SMTR 1:1 molecular complex were also investigated and the theoretical and experimental phase diagrams of the individual components were assessed. The existence of polymorphic and pseudopolymorphic forms is determined by conformational flexibility of the TXP‐SMTR bimolecular complex components, a tendency for molecular disorder in TXP, the ability of the drug complex to form intricate, highly stabilized hydrogen‐bonded frameworks, and the competition between nonspecific van der Waals and specific hydrogen bond interactions. © 2003 Wiley‐Liss, Inc. and the American Pharmacists Association J Pharm Sci 92:2164–2176, 2003

  • structural relationships thermal properties and physicochemical characterization of anhydrous and solvated crystalline forms of Tetroxoprim
    Journal of Pharmaceutical Sciences, 2002
    Co-Authors: Mino R Caira, Giampiero Bettinetti, Milena Sorrenti
    Abstract:

    Abstract Six distinct phases of the antibacterial Tetroxoprim (TXP) have been isolated by recrystallization from various solvents. These comprise two polymorphs, forms I and II, and four solvates with the following solvents and TXP solvent stoichiometric ratios: chloroform (3:2), water (3:2), methanol (2:1), and ethanol (2:1). Thermal and infrared spectral data showed that forms I and II are enantiotropically related with form II being stable below the transition temperature of 118°C and form I melting at 159°C. The crystal structure of form I contains three crystallographically independent TXP molecules arranged in layers formed by extensive base pairing between the 2,4‐diaminopyrimidine rings. This species invariably results upon heating the solvates of TXP. Thermogravimetry and differential scanning calorimetry respectively showed one‐step mass losses and progressively increasing desolvation temperatures for the solvates with chloroform, water, ethanol, and methanol. X‐ray diffraction studies revealed that the latter three solvates are isostructural, belonging to the class of “isolated site” solvates. Extensive base pairing maintains the common TXP crystalline framework. Thermal data for the desolvation of these phases are reconciled with the observed crystal packing features. Experimental and computed powder X‐ray patterns for form I and the solvates with water, methanol, and ethanol are presented.

Milena Sorrenti - One of the best experts on this subject based on the ideXlab platform.

  • thermal studies of solvent exchange in isostructural solvates of a Tetroxoprim sulfametrole complex
    Journal of Thermal Analysis and Calorimetry, 2004
    Co-Authors: Giampiero Bettinetti, Mino R Caira, Milena Sorrenti, Laura Catenacci, M Ghirardi, Laszlo Fabian
    Abstract:

    Isostructural solvates of the 1:1 molecular complex between the antibacterial drugs Tetroxoprim (TXP) and sulfametrole (SMTR) with formulae TXP·SMTR·CH3OH (I), TXP·SMTR·C2H5OH (II) and TXP·SMTR·H2O (III), were investigated to establish their propensity for guest exchange. Separate exposure of powdered (I), (II) and (III) to a saturated atmosphere of each solvent of the complementary solvate pair at ambient temperature resulted in reversible solvent exchange in all cases. DSC and TG were the methods of choice for monitoring the exchange processes since (I)-(III) have distinct onset temperatures of desolvation and characteristic mass losses. Interpretation of the results in terms of the known locations of the solvent molecules in crystals of (I)-(III) led to the conclusion that solvent exchange probably proceeds by a co-operative mechanism involving material transport through channels while the common host framework is maintained.

  • order disorder enantiotropy monotropy and isostructurality in a Tetroxoprim sulfametrole 1 1 molecular complex crystallographic and thermal studies
    Journal of Pharmaceutical Sciences, 2003
    Co-Authors: Mino R Caira, Giampiero Bettinetti, Milena Sorrenti, Laura Catenacci
    Abstract:

    Abstract Two enantiotropic polymorphs of a Tetroxoprim (TXP)‐sulfametrole (SMTR) 1:1 molecular complex monohydrate and two isostructural TXP‐SMTR 1:1 molecular complex solvates with methanol and ethanol were grown and studied by X‐ray diffraction and thermal methods (thermogravimetric analysis and differential scanning calorimetry). Interconversion of the polymorphic hydrates is essentially an order/disorder transition involving a substituent on the TXP molecule. These hydrated phases may be described as “nearly isostructural” with the methanol and ethanol solvates. Thermal data for decomposition of the solvates were rationalized on the basis of the location and topologies of solvent crystallographic sites. Solid‐state properties of two monotropic polymorphs of the unsolvated TXP‐SMTR 1:1 molecular complex were also investigated and the theoretical and experimental phase diagrams of the individual components were assessed. The existence of polymorphic and pseudopolymorphic forms is determined by conformational flexibility of the TXP‐SMTR bimolecular complex components, a tendency for molecular disorder in TXP, the ability of the drug complex to form intricate, highly stabilized hydrogen‐bonded frameworks, and the competition between nonspecific van der Waals and specific hydrogen bond interactions. © 2003 Wiley‐Liss, Inc. and the American Pharmacists Association J Pharm Sci 92:2164–2176, 2003

  • structural relationships thermal properties and physicochemical characterization of anhydrous and solvated crystalline forms of Tetroxoprim
    Journal of Pharmaceutical Sciences, 2002
    Co-Authors: Mino R Caira, Giampiero Bettinetti, Milena Sorrenti
    Abstract:

    Abstract Six distinct phases of the antibacterial Tetroxoprim (TXP) have been isolated by recrystallization from various solvents. These comprise two polymorphs, forms I and II, and four solvates with the following solvents and TXP solvent stoichiometric ratios: chloroform (3:2), water (3:2), methanol (2:1), and ethanol (2:1). Thermal and infrared spectral data showed that forms I and II are enantiotropically related with form II being stable below the transition temperature of 118°C and form I melting at 159°C. The crystal structure of form I contains three crystallographically independent TXP molecules arranged in layers formed by extensive base pairing between the 2,4‐diaminopyrimidine rings. This species invariably results upon heating the solvates of TXP. Thermogravimetry and differential scanning calorimetry respectively showed one‐step mass losses and progressively increasing desolvation temperatures for the solvates with chloroform, water, ethanol, and methanol. X‐ray diffraction studies revealed that the latter three solvates are isostructural, belonging to the class of “isolated site” solvates. Extensive base pairing maintains the common TXP crystalline framework. Thermal data for the desolvation of these phases are reconciled with the observed crystal packing features. Experimental and computed powder X‐ray patterns for form I and the solvates with water, methanol, and ethanol are presented.

Murat Topal - One of the best experts on this subject based on the ideXlab platform.

  • Elazığ Belediyesi Atıksu Arıtma Tesisi Giriş Sularında Antibiyotik Kalıntılarının Varlığının Araştırılması / Investigation Of The Presence Of Antibiotic Residues Influent Of Elazig Municipal Wastewater Treatment Plant
    Karabuk University, 2012
    Co-Authors: Murat Topal
    Abstract:

    Bu çalışmada, Elazığ Belediyesi Atıksu Arıtma Tesisi giriş sularında antibiyotik kalıntılarının varlığının belirlenmesi amaçlanmıştır. Bu amaç için, arıtma tesisi giriş suyundan kompozit numune alınmış ve analizler yapılmıştır. Analiz sonuçlarına göre Elazığ Belediyesi Atıksu Arıtma Tesisi giriş sularında makrolidler (azitromisin, klaritromisin, eritromisin), beta laktamlar (aztreonam, sefalosporinler (sefamandol, sefepim, sefiksim), rifampisin (rifamisin)) ve sülfonamid (tetroksoprim) antibiyotikleri bulunmuştur. Investigation Of The Presence Of Antibiotic Residues Influent Of Elazig Municipal Wastewater Treatment Plant In this study, it was aimed to determine the presence of antibiotic residues in influents of Elazığ Municipal Wastewater Treatment Plant. For this aim, composite sample was taken from the influents of the treatment plant and analyses were done. According to the results of the analyses, macrolides (azitromycin, clarithromycin, erithromycin), beta lactams (aztreonam, cefalosporines (cefamondole, cefepime, cefixime), rifampicine (rifamycin)) and sulfonamide (Tetroxoprim) antibiotics were obtained in influents of Elazig Municipal Wastewater Treatment Plant

  • Elazığ Belediyesi Atıksu Arıtma Tesisi Giriş Sularında Antibiyotik Kalıntılarının Varlığının Araştırılması
    Karabuk University, 2012
    Co-Authors: Murat Topal
    Abstract:

    ÖzetBu çalışmada, Elazığ Belediyesi Atıksu Arıtma Tesisi giriş sularında antibiyotik kalıntılarının varlığının belirlenmesi amaçlanmıştır. Bu amaç için, arıtma tesisi giriş suyundan kompozit numune alınmış ve analizler yapılmıştır. Analiz sonuçlarına göre Elazığ Belediyesi Atıksu Arıtma Tesisi giriş sularında makrolidler (azitromisin, klaritromisin, eritromisin), beta laktamlar (aztreonam, sefalosporinler (sefamandol, sefepim, sefiksim), rifampisin (rifamisin)) ve sülfonamid (tetroksoprim) antibiyotikleri bulunmuştur. AbstractIn this study, it was aimed to determine the presence of antibiotic residues in influents of Elazığ Municipal Wastewater Treatment Plant. For this aim, composite sample was taken from the influents of the treatment plant and analyses were done. According to the results of the analyses, macrolides (azitromycin, clarithromycin, erithromycin), beta lactams (aztreonam, cefalosporines (cefamondole, cefepime, cefixime), rifampicine (rifamycin)) and sulfonamide (Tetroxoprim) antibiotics were obtained in influents of Elazig Municipal Wastewater Treatment Plant