39 research outputs found
Stereosopecificity in [Co(sep)][Co(edta)]Cl<sub>2</sub>·2H<sub>2</sub>O
The X-ray structure of racemic [Co(sep)][Co(edta)]Cl2·2H2O is reported and reveals hetero-chiral stereospecificity in the interactions of [Co(sep)]3+ with [Co(edta)]−. Hydrogen-bonding along the molecular C2-axes of both complexes accounts for the stereospecificity. The structure of Λ-[Co(en)3]∆-[Co(edta)]2Cl·10H2O has been re-determined. Previous structural data for this compound were collected at room temperature and the model did not sufficiently describe the disorder in the structure. The cryogenic temperature used in the present study allows the disorder to be conformationally locked and modeled more reliably. A clearer inspection of other, structurally interesting, interactions is possible. Again, hydrogen-bonding along the molecular C2-axis of [Co(en)3]3+ and the equatorial carboxylates of [Co(edta)]− is the important interaction. The unique nature of the equatorial carboxylates and molecular C2-axis in [Co(edta)]−, straddled by two pseudo-C3-faces where the arrangement of the carboxylate groups conveys the same helicity, is highlighted. Implications of these structures in understanding stereoselectivity in ion-pairing and electron transfer reactions are discussed
Stereosopecificity in [Co(sep)][Co(edta)]Cl2·2H2O
The X-ray structure of racemic [Co(sep)][Co(edta)]Cl2·2H2O is reported and reveals hetero-chiral stereospecificity in the interactions of [Co(sep)]3+ with [Co(edta)]−. Hydrogen-bonding along the molecular C2-axes of both complexes accounts for the stereospecificity. The structure of Λ-[Co(en)3]∆-[Co(edta)]2Cl·10H2O has been re-determined. Previous structural data for this compound were collected at room temperature and the model did not sufficiently describe the disorder in the structure. The cryogenic temperature used in the present study allows the disorder to be conformationally locked and modeled more reliably. A clearer inspection of other, structurally interesting, interactions is possible. Again, hydrogen-bonding along the molecular C2-axis of [Co(en)3]3+ and the equatorial carboxylates of [Co(edta)]− is the important interaction. The unique nature of the equatorial carboxylates and molecular C2-axis in [Co(edta)]−, straddled by two pseudo-C3-faces where the arrangement of the carboxylate groups conveys the same helicity, is highlighted. Implications of these structures in understanding stereoselectivity in ion-pairing and electron transfer reactions are discussed
Metabolism of methyl-(E)-2-2-6-(2-cyanophenoxy)pyrimidin-4- yloxyphenyl-3-methoxyacrylate (azoxystrobin) in rat
1. The metabolic fate of 14C-methyl-(E)-2-{2-6-(2-cyanophenoxy)pyrimidin-4- yloxyphenyl}-3-methoxyacrylate (azoxystrobin) was determined in the male and female rat following a single oral dose of 1 and 100 mg kg-1 and in surgically prepared, bile duct-cannulated rats following a single oral dose of 100mg kg-1. 2. Azoxystrobin was extensively metabolized with at least 15 metabolites. There was a sex difference, with females producing more metabolites than males. 3. The two principal metabolic pathways were hydrolysis of the methoxyacid followed by glucuronic acid conjugation and glutathione conjugation of the cyanophenyl ring followed by further metabolism leading to the mercapturic acid. There were also several other minor pathways
Crystal structure of tris(trans-1,2-diaminocyclohexane-κ2N,N′)cobalt(III) trichloride monohydrate
The synthesis of the title hydrated complex salt, [Co(C6H14N2)3]Cl3·H2O, from racemic trans-1,2-diaminocyclohexane and [CoCl(NH3)5]Cl2 and its structural characterization are presented in this paper. The product was synthesized in the interest of understanding the hydrogen-bonding patterns of coordination complexes. Previous characterizations of the product in the I-42d space group have not yielded coordinates; thus, this paper provides the first coordinates for this complex in this space group. The octahedrally coordinated cation adopts twofold rotation symmetry, with outer-sphere chloride counter-ions and solvent water molecules forming a hydrogen-bonded network with amine H atoms