118337-48-7Relevant articles and documents
Fluorinated analogues as mechanistic probes in valproic acid hepatotoxicity: Hepatic microvesicular steatosis and glutathione status
Tang,Borel,Fujimiya,Abbott
, p. 671 - 682 (1995)
It is postulated that the hepatotoxicity of valproic acid (VPA) results from the mitochondrial β-oxidation of its cytochrome P450 metabolite, 2- propyl-4-pentenoic acid (4-ene VPA), to 2-propyl-(E)-2,4-pentadienoic acid ((E)-2,4-diene VPA) which, in the CoA thioester form, either depletes GSH or produces a putative inhibitor of β-oxidation enzymes. In order to test this hypothesis, 2-fluoro-2-propyl-4-pentenoic acid (α-fluoro-4-ene VPA) which was expected to be inert to β-oxidative metabolism was synthesized and its effect on rat liver studied in comparison with that of 4-ene VPA. Similarly, the known hepatotoxicant 4-pentenoic acid (4-PA) and 2,2-difluoro-4-pentenoic acid (F2-4-PA) were compared. Male Sprague-Dawley rats (150-180 g, 4 rats per group) were dosed ip with 4-one VPA (0.7 mmol/kg per day), 4-PA (1.0 mmol/kg per day), or equivalent amounts of their α-fluorinated analogues for 5 days. Both 4-ene VPA and 4-PA induced severe hepatic microvesicular steatosis (> 85% affected hepatocytes), and 4-ene VPA produced mitochondrial alterations. By contrast, α-fluoro-4-ene VPA and F2-4-PA were not observed to cause morphological changes in the liver. The major metabolite of 4-ene VPA in the rat urine and serum was the β-oxidation product (E)-2,4-diene VPA. The N-acetylcysteine (NAC) conjugate of (E)-2,4-diene VPA was also found in the urine. Neither (E)-2,4-diene VPA nor the NAC conjugate could be detected in the rats administered α-fluoro-4-ene VPA. In a second set of rats (3 rats per group), total liver GSH levels were determined to be depleted to 56% and 72% of control following doses of 4-ene VPA (1.4 mmol/kg) and equivalent α-fluoro-4-ene VPA, respectively. Mitochondrial GSH remained unchanged in the α-fluoro-4-ene VPA treated group but was reduced to 68% of control in the rats administered 4-ene VPA. These results strongly support the theory that hepatotoxicity of 4-ene VPA, and possibly VPA itself, is mediated largely through β-oxidation of 4-ene VPA to reactive intermediates that are capable of depleting mitochondrial GSH.
Novel Synthesis of 2,2,2-Trifluoroethyl Compounds from Homoallylic Alcohols: A Copper(I) Iodide-initiated Trifluoromethyl-Dehydroxylation Process
Duan, Jian-Xing,Chen, Quing-Yun
, p. 725 - 730 (2007/10/02)
Benzyl, prop-2-enyl and allyl chlorodifluoroacetates 3a, bromodifluoroacetates 3b or fluorosulfonyldifluoroacetates 3c, when decomposed in the presence of 1 equivalent of copper(I) iodide at an appropriate temperature in dimethylformamide, gave the corresponding trifluoromethyl derivatives in good to excellent yields.The products can also be obtained directly by ester exchange of XCF2CO2Et (X = FSO2, Cl, Br) 6 and the corresponding alcohols in the presence of KF and CuI.A trifluoromethylation-dehydroxylation mechanism, initiated by CuI, is proposed.
