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Benson M Kariuki - One of the best experts on this subject based on the ideXlab platform.
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Polymorphic phase transformations of 3-chloro-Trans-Cinnamic Acid and its solid solution with 3-bromo-Trans-Cinnamic Acid.
Acta crystallographica. Section C Structural chemistry, 2018Co-Authors: Manal A Khoj, Colan E Hughes, Kenneth D M Harris, Benson M KariukiAbstract:We have investigated the polymorphic phase transformations above ambient temperature for 3-chloro-Trans-Cinnamic Acid (3-ClCA, C9H7ClO2) and a solid solution of 3-ClCA and 3-bromo-Trans-Cinnamic Acid (3-BrCA, C9H7BrO2). At 413 K, the γ polymorph of 3-ClCA transforms to the β polymorph. Interestingly, the structure of the β polymorph of 3-ClCA obtained in this transformation is different from the structure of the β polymorph of 3-BrCA obtained in the corresponding polymorphic transformation from the γ polymorph of 3-BrCA, even though the γ polymorphs of 3-ClCA and 3-BrCA are isostructural. We also report a high-temperature phase transformation from a γ-type structure to a β-type structure for a solid solution of 3-ClCA and 3-BrCA (with a molar ratio close to 1:1). The γ polymorph of the solid solution is isostructural with the γ polymorphs of pure 3-ClCA and pure 3-BrCA, while the β-type structure produced in the phase transformation is structurally similar to the β polymorph of pure 3-BrCA.
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Structural Diversity of Solid Solutions Formed between 3-Chloro-Trans-Cinnamic Acid and 3-Bromo-Trans-Cinnamic Acid
Crystal Growth & Design, 2017Co-Authors: Manal A Khoj, Colan E Hughes, Kenneth D M Harris, Benson M KariukiAbstract:The formation and structural properties of solid solutions containing 3-chloro-Trans-Cinnamic Acid (3-ClCA) and 3-bromo-Trans-Cinnamic Acid (3-BrCA) are explored across a range of compositions. Two distinct γ-type structures of 3-ClCA/3-BrCA solid solutions and two distinct β-type structures of 3-ClCA/3-BrCA solid solutions are reported and structurally characterized. One of the γ-type structures is isostructural with the known γ polymorphs of pure 3-ClCA and pure 3-BrCA, whereas the other γ-type structure has not been observed previously for either pure 3-ClCA or pure 3-BrCA (representing a rare case in which the structure of the solid solution is not known for the pure phases of either of the constituent molecules). One of the β-type structures of the 3-ClCA/3-BrCA solid solutions is similar to the β polymorph of pure 3-ClCA, whereas the other β-type structure is similar to the β polymorph of pure 3-BrCA. The specific β-type structure formed is found to depend on the relative amounts of 3-BrCA and 3-ClC...
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Polymorphic phase transformation in the 3-bromo-Trans-Cinnamic Acid system
IEEE Journal of Solid-state Circuits, 2002Co-Authors: Kenneth D M Harris, Benson M KariukiAbstract:3-Bromo- trans -cinnamic Acid (3-BrCA) exists as two crystalline polymorphic forms (designated as β and γ phases). A polymorphic phase transformation from the γ phase to the β phase has been investigated using ex situ powder X-ray diffraction, in situ high-temperature optical microscopy, and differential scanning calorimetry. The transformation occurs at an observable rate at temperatures above about 100°C. A reverse transformation on subsequently cooling the β phase is not observed. Thermodynamic aspects of the polymorphic 3-BrCA system are discussed, together with kinetic aspects of the transformation from the γ phase to the β phase. The structural properties of the β phase (reported previously) and the γ phase (determined in this work from single-crystal X-ray diffraction data) are in accord with the α / β / γ structural classification of trans -cinnamic Acid derivatives.
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Crystal Structure Solution from Powder X-ray Diffraction Data: The Development of Monte Carlo Methods To Solve the Crystal Structure of the γ-Phase of 3-Chloro-Trans-Cinnamic Acid†
Chemistry of Materials, 1996Co-Authors: Benson M Kariuki, Maryjane Tremayne, Kenneth D M HarrisAbstract:Many important crystalline materials do not form single crystals of sufficient size and/or quality for single-crystal diffraction studies, and in such cases it is essential that the crystal structure can be solved from powder diffraction data; however, there are many difficulties associated with solving crystal structures, ab initio, from powder diffraction data. In this paper, we report the successful application of a Monte Carlo technique to solve the (previously unknown) crystal structure of the γ-phase of 3-chloro-Trans-Cinnamic Acid from powder X-ray diffraction data. The “structural fragment” used in the Monte Carlo calculation comprised a rigid Trans-Cinnamic Acid molecule (with the chlorine and hydrogen atoms omitted) with its oxygen atoms at a fixed distance from the crystallographic center of symmetry, and with the center of symmetry lying in the molecular plane. The structural fragment was rotated by a random angular displacement around a random axis constrained to pass through the center of sy...
Kenneth D M Harris - One of the best experts on this subject based on the ideXlab platform.
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Polymorphic phase transformations of 3-chloro-Trans-Cinnamic Acid and its solid solution with 3-bromo-Trans-Cinnamic Acid.
Acta crystallographica. Section C Structural chemistry, 2018Co-Authors: Manal A Khoj, Colan E Hughes, Kenneth D M Harris, Benson M KariukiAbstract:We have investigated the polymorphic phase transformations above ambient temperature for 3-chloro-Trans-Cinnamic Acid (3-ClCA, C9H7ClO2) and a solid solution of 3-ClCA and 3-bromo-Trans-Cinnamic Acid (3-BrCA, C9H7BrO2). At 413 K, the γ polymorph of 3-ClCA transforms to the β polymorph. Interestingly, the structure of the β polymorph of 3-ClCA obtained in this transformation is different from the structure of the β polymorph of 3-BrCA obtained in the corresponding polymorphic transformation from the γ polymorph of 3-BrCA, even though the γ polymorphs of 3-ClCA and 3-BrCA are isostructural. We also report a high-temperature phase transformation from a γ-type structure to a β-type structure for a solid solution of 3-ClCA and 3-BrCA (with a molar ratio close to 1:1). The γ polymorph of the solid solution is isostructural with the γ polymorphs of pure 3-ClCA and pure 3-BrCA, while the β-type structure produced in the phase transformation is structurally similar to the β polymorph of pure 3-BrCA.
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Structural Diversity of Solid Solutions Formed between 3-Chloro-Trans-Cinnamic Acid and 3-Bromo-Trans-Cinnamic Acid
Crystal Growth & Design, 2017Co-Authors: Manal A Khoj, Colan E Hughes, Kenneth D M Harris, Benson M KariukiAbstract:The formation and structural properties of solid solutions containing 3-chloro-Trans-Cinnamic Acid (3-ClCA) and 3-bromo-Trans-Cinnamic Acid (3-BrCA) are explored across a range of compositions. Two distinct γ-type structures of 3-ClCA/3-BrCA solid solutions and two distinct β-type structures of 3-ClCA/3-BrCA solid solutions are reported and structurally characterized. One of the γ-type structures is isostructural with the known γ polymorphs of pure 3-ClCA and pure 3-BrCA, whereas the other γ-type structure has not been observed previously for either pure 3-ClCA or pure 3-BrCA (representing a rare case in which the structure of the solid solution is not known for the pure phases of either of the constituent molecules). One of the β-type structures of the 3-ClCA/3-BrCA solid solutions is similar to the β polymorph of pure 3-ClCA, whereas the other β-type structure is similar to the β polymorph of pure 3-BrCA. The specific β-type structure formed is found to depend on the relative amounts of 3-BrCA and 3-ClC...
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Polymorphic phase transformation in the 3-bromo-Trans-Cinnamic Acid system
IEEE Journal of Solid-state Circuits, 2002Co-Authors: Kenneth D M Harris, Benson M KariukiAbstract:3-Bromo- trans -cinnamic Acid (3-BrCA) exists as two crystalline polymorphic forms (designated as β and γ phases). A polymorphic phase transformation from the γ phase to the β phase has been investigated using ex situ powder X-ray diffraction, in situ high-temperature optical microscopy, and differential scanning calorimetry. The transformation occurs at an observable rate at temperatures above about 100°C. A reverse transformation on subsequently cooling the β phase is not observed. Thermodynamic aspects of the polymorphic 3-BrCA system are discussed, together with kinetic aspects of the transformation from the γ phase to the β phase. The structural properties of the β phase (reported previously) and the γ phase (determined in this work from single-crystal X-ray diffraction data) are in accord with the α / β / γ structural classification of trans -cinnamic Acid derivatives.
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Crystal Structure Solution from Powder X-ray Diffraction Data: The Development of Monte Carlo Methods To Solve the Crystal Structure of the γ-Phase of 3-Chloro-Trans-Cinnamic Acid†
Chemistry of Materials, 1996Co-Authors: Benson M Kariuki, Maryjane Tremayne, Kenneth D M HarrisAbstract:Many important crystalline materials do not form single crystals of sufficient size and/or quality for single-crystal diffraction studies, and in such cases it is essential that the crystal structure can be solved from powder diffraction data; however, there are many difficulties associated with solving crystal structures, ab initio, from powder diffraction data. In this paper, we report the successful application of a Monte Carlo technique to solve the (previously unknown) crystal structure of the γ-phase of 3-chloro-Trans-Cinnamic Acid from powder X-ray diffraction data. The “structural fragment” used in the Monte Carlo calculation comprised a rigid Trans-Cinnamic Acid molecule (with the chlorine and hydrogen atoms omitted) with its oxygen atoms at a fixed distance from the crystallographic center of symmetry, and with the center of symmetry lying in the molecular plane. The structural fragment was rotated by a random angular displacement around a random axis constrained to pass through the center of sy...
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The rôle of powder diffraction in establishing structure–property relationships for crystalline solids: a new structural assignment of the photoreactive and photostable phases of p-formyl-Trans-Cinnamic Acid
Journal of The Chemical Society-perkin Transactions 1, 1994Co-Authors: Kenneth D M Harris, Iain L. J. PattersonAbstract:It has been reported previously that the photoreactive β phase of p-formyl-Trans-Cinnamic Acid represents an exception to the well-established correlation between structural and photochemical properties of crystalline Trans-Cinnamic Acid derivatives. However, it is shown in this paper that the crystal structure reported previously to be the β phase of p-formyl-Trans-Cinnamic Acid is actually the photostable γ phase. In a wider context, the work reported here highlights the necessity of carrying out powder diffraction investigations in the determination of structure–property relationships for crystalline solids.
Bradley S. Moore - One of the best experts on this subject based on the ideXlab platform.
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biochemical characterization of a prokaryotic phenylalanine ammonia lyase
Journal of Bacteriology, 2005Co-Authors: Longkuan Xiang, Bradley S. MooreAbstract:The committed biosynthetic reaction to benzoyl-coenzyme A in the marine bacterium “Streptomyces maritimus” is carried out by the novel prokaryotic phenylalanine ammonia lyase (PAL) EncP, which converts the primary amino Acid l-phenylalanine to Trans-Cinnamic Acid. Recombinant EncP is specific for l-phenylalanine and shares many biochemical features with eukaryotic PALs, which are substantially larger proteins by ∼200 amino Acid residues.
Eckhard Boles - One of the best experts on this subject based on the ideXlab platform.
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De novo biosynthesis of Trans-Cinnamic Acid derivatives in Saccharomyces cerevisiae
Applied Microbiology and Biotechnology, 2017Co-Authors: Manuela Gottardi, Jan Dines Knudsen, Lydie Prado, Mislav Oreb, Paola Branduardi, Eckhard BolesAbstract:The production of natural aroma compounds is an expanding field within the branch of white biotechnology. Three aromatic compounds of interest are cinnamaldehyde, the typical cinnamon aroma that has applications in agriculture and medical sciences, as well as cinnamyl alcohol and hydrocinnamyl alcohol, which have applications in the cosmetic industry. Current production methods, which rely on extraction from plant materials or chemical synthesis, are associated with drawbacks regarding scalability, production time, and environmental impact. These considerations make the development of a sustainable microbial-based production highly desirable. Through steps of rational metabolic engineering, we engineered the yeast Saccharomyces cerevisiae as a microbial host to produce trans -cinnamic Acid derivatives cinnamaldehyde, cinnamyl alcohol, and hydrocinnamyl alcohol, from externally added trans -cinnamic Acid or de novo from glucose as a carbon source. We show that the desired products can be de novo synthesized in S. cerevisiae via the heterologous overexpression of the genes encoding phenylalanine ammonia lyase 2 from Arabidopsis thaliana ( AtPAL2 ), aryl carboxylic Acid reductase (acar) from Nocardia sp., and phosphopantetheinyl transferase ( entD ) from Escherichia coli , together with endogenous alcohol dehydrogenases. This study provides a proof of concept and a strain that can be further optimized for production of high-value aromatic compounds.
Evan M Curtin - One of the best experts on this subject based on the ideXlab platform.
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Determination of Abraham model solute descriptors for the monomeric and dimeric forms of Trans-Cinnamic Acid using measured solubilities from the Open Notebook Science Challenge
Chemistry Central Journal, 2015Co-Authors: Jean-claude Bradley, Michael H Abraham, William E Acree, Andrew Sid Lang, Samantha N Beck, David A Bulger, Elizabeth A Clark, Lacey N Condron, Stephanie T Costa, Evan M CurtinAbstract:Background Calculating Abraham descriptors from solubility values requires that the solute have the same form when dissolved in all solvents. However, carboxylic Acids can form dimers when dissolved in non-polar solvents. For such compounds Abraham descriptors can be calculated for both the monomeric and dimeric forms by treating the polar and non-polar systems separately. We illustrate the method of how this can be done by calculating the Abraham descriptors for both the monomeric and dimeric forms of Trans-Cinnamic Acid, the first time that descriptors for a carboxylic Acid dimer have been obtained. Results Abraham descriptors were calculated for the monomeric form of Trans-Cinnamic Acid using experimental solubility measurements in polar solvents from the Open Notebook Science Challenge together with a number of water-solvent partition coefficients from the literature. Similarly, experimental solubility measurements in non-polar solvents were used to determine Abraham descriptors for the Trans-Cinnamic Acid dimer. Conclusion Abraham descriptors were calculated for both the monomeric and dimeric forms of Trans-Cinnamic Acid. This allows for the prediction of further solubilities of Trans-Cinnamic Acid in both polar and non-polar solvents with an error of about 0.10 log units. Graphical abstract Molar concentration of Trans-Cinnamic Acid in various polar and non-polar solvents.
