3919-74-2Relevant articles and documents
Synthesis, Crystal Structure, and Herbicidal Activity of 3-(2-Chloro-6-fuorophenyl)-4-(2-oxooxazolidine-3-carbonyl)-5-methylisoxazole
Guo, You-Yuan,Jiang, Wei,Yang, Hong-Li,Fu, Ying
, p. 503 - 508 (2021/02/02)
ABSTRACT A novel N-aroyl diketone derivative, 3-(2-chloro-6-fluorophenyl)-4-(2-oxooxazolidine-3-carbonyl)-5-methylisoxazole (C14H10ClFN2O4, Mr=324.69), was designed via fragment analysis and coupling strategy that led to highly potent and bio-selective herbicide. The title compound was prepared by a multistep-reaction, including nucleophilic addition and N-acylation reaction using 2-chloro-6-fluorobenzaldehyde as the starting materials in 83.4% yield. The product was characterized by infrared, proton nuclear magnetic resonance, Carbon-13 nuclear magnetic resonance, human resource management system, and X-ray diffraction. The title compound crystallized in the monoclinic system, space group P21/n with a=10.7119(4) ?, b=17.5875(7) ?, c=11.5151(7) ?, b=100.927(2)°, Z=8, V=2870.0(2) ?3, F(000)=1328, Dc=1.503 Mg/m3, crystal size: 0.130 × 0.120 ×0.100 mm. The herbicidal activity was tested against the gramineous weed Echinochloa crus-galli and broadleaf Abutilon juncea.
Removal of toxic tellurium (IV) compounds via bioreduction using flucloxacillin in aqueous acidic medium: A kinetic and mechanistic approach
Fawzy, Ahmed
, (2019/09/06)
This paper describes a novel method for the removal of potassium tellurite (TeIV), a toxic tellurium (IV) compound, via its bioreduction using the drug flucloxacillin (Flx) in an aqueous sulfuric acid solution. The kinetics of the bioreduction process were monitored using UV–Vis absorption spectra at an ionic strength of 2.0 mol dm?3 and 298 K. The reaction between TeIV and Flx was set at a 1:1 stoichiometry. The reduction reaction followed first-order kinetics for [Flx] and fractional-first-order kinetics for [TeIV] and [H+]. The effects of ionic strength and relative permittivity of the reaction medium were also explored. Supplementation with divalent transition metal ions enhanced the reduction rate. The reaction products were identified, in order of their stoichiometric results, spot tests and FT-IR spectra as 3-(2-chloro-6-fluorophenyl)-5-methylisoxazol-4-carbocylic acid, 5,5-dimethyl-thiazolidine-2,4-dicarboxlic acid, ammonium ion, carbon dioxide and elemental tellurium (Te0). The reaction rate dependence on temperature was studied, and the activation and thermodynamic parameters were assessed and discussed. The derived rate-law expression was found to be in excellent accordance with the acquired investigational outcomes. A conceivable reaction mechanism has been provided, which includes a reaction between the protonated flucloxacillin (Flx+) and tellurous acid (H2TeO3) as the essential reactive species, resulting in the construction of an intermediate complex. Such complex decays in the rate-determining step to yield the final reaction products.
IMPROVED PROCESS FOR PREPARING PENICILLINS AND INTERMEDIATE COMPOUNDS
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Page/Page column 11, (2013/02/27)
Disclosed is an improved process for the preparation of isoxazolyl penicillins of formula (I), wherein X1 and X2 can be independently selected from the group comprising hydrogen, chlorine or fluorine, and its pharmaceutically suitable salts. The process is economic in -situ synthetic method without isolation of any intermediate. (I).