3121-68-4Relevant academic research and scientific papers
Catalytic Redox Chain Ring Opening of Lactones with Quinones to Synthesize Quinone-Containing Carboxylic Acids
Xu, Xiao-Long,Li, Zhi
, p. 5078 - 5081 (2019/09/03)
Catalytic ring opening of five- to eight-membered lactones with quinones is achieved through a redox chain mechanism. With low loading of a simple metal triflate Lewis acid catalyst and a chain initiator, C-H bonds of many quinones were efficiently functionalized with carboxylic acid-containing side chains. This method also features 100% atom economy and wide substrate scope. A novel route to the anti-asthma drug Seratrodast was developed. Mechanism study suggests that the redox chain reaction likely undergoes a carbocation intermediate.
CARBOXYLIC ACID DERIVATIVES FOR TREATMENT OF OXIDATIVE STRESS DISORDERS
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Paragraph 0135, (2014/12/12)
Disclosed herein are compounds and methods of using such compounds for treating or suppressing oxidative stress disorders, including mitochondrial disorders, impaired energy processing disorders, neurodegenerative diseases and diseases of aging, or for modulating one or more energy biomarkers, normalizing one or more energy biomarkers, or enhancing one or more energy biomarkers, wherein the compounds are quinone or naphthoquinone compounds with carboxylic acid or carboxylic acid derivative substituents.
Isolation and identification of α-CEHC sulfate in rat urine and an improved method for the determination of conjugated α-CEHC
Li, Yi-Jen,Luo, Sheng-Ching,Lee, Yi-Jing,Lin, Fu-Jung,Cheng, Chi-Cheng,Wein, Yung-Shung,Kuo, Yueh-Hsiung,Huang, Ching-Jang
scheme or table, p. 11105 - 11113 (2010/07/20)
2,5,7,8-Tetramethyl-2-(2′-carboxyethyl)-6-hydroxychroman (α-CEHC), the water-soluble metabolite of α-tocopherol (α-TOH) with a shortened side chain but an intact hydroxychroman structure, has been identified in human urine and are thought to be produced in significant amount at excess intake of α-TOH. In previous studies, CEHCs in biological specimens were measured by HPLC, GC-MS or LC-MS, preceded by a hydrolysis procedure using either enzyme or methanolic HCl. In an attempt to analyze α-CEHC in rat urine accordingly, we observed that enzyme hydrolysis was relatively inefficient in releasing α-CEHC compared to high concentrations of HCl. The HCl releasable α-CEHC conjugate was isolated and chemically identified as 6-O-sulfated α-CEHC (α-CEHC sulfate). Using the synthetic α-CEHC sulfate standard, it was found that sulfatase could not hydrolyze to a significant extent. On the other hand, pretreatment with HCl at 60°C in the presence of ascorbate, followed by a one-step ether extraction, not only hydrolyzed the sulfate conjugate completely but also extracted α-CEHC with high recovery. The inclusion of ascorbate minimized the conversion of α-CEHC to α-tocopheronolactone in the HCl pretreatment. A complete procedure for the quantitative analysis of α-CEHC including HCl hydrolysis, ether extraction and reverse phase isocratic HPLC-ECD was thus established. In conclusion, α-CEHC sulfate was isolated and identified as the HCl-releasable conjugate of α-CEHC in rat urine. A rapid and sensitive method with high reproducibility for the determination of free, conjugated and total α-CEHC is then established.
Endogenous natriuretic factors 6: The stereochemistry of a natriuretic γ-tocopherol metabolite LLU-α
Kantoci, Darko,Wechter, William J.,Murray Jr., E. David,Dewind, Sally A.,Borchardt, Dan,Khan, Saeed I.
, p. 648 - 656 (2007/10/03)
2,7,8-Trimethyl-(S)-2-(β-carboxyethyl)-6-hydroxy chroman (S-LLU-α) isolated from human uremic urine is apparently an oxidative side-chain degradation product of γ-tocopherol. This compound exhibits natriuretic activity in vivo and it appears to mediate the inhibition of the 70 pS K+ channel in the apical membrane of the thick ascending limb of the nephron. The stereochemistry at the C-2 of LLU-α has been unequivocally established to be S(+) by X-ray crystallographic analysis of a diastereomeric amide derivative. It was also established that the chroman ring oxidation of S- LLU-α proceeded without racemization at C-2. This finding can be extended to nonepimerization at C-2 of α-δ tocopherols (Vitamin E) during side-chain oxidation and stereospecificity (retention or inversion) of oxidative opening of the chroman ring. The resolution of the enantiomers of the parent compound and derivatives was accomplished by chiral high-performance liquid chromatography. The stereospecific enzymatic hydrolysis by an array of commercially available enzymes of the racemic methyl ester of LLU-α was investigated. The lipase from Humicola languinosa appears to be the best enzyme for resolution by selective hydrolysis of the racemic methyl ester.
