Methods and compositions for determing a level of biologically active serum paraoxonase
申请人:Tawfik Dan S.
公开号:US20090305239A1
公开(公告)日:2009-12-10
A method of determining a level of biologically active PON enzyme is provided. The method comprising determining lactonase activity of the PON enzyme, the lactonase activity being indicative of the level of biologically active PON enzyme. Also provided are novel compounds which may be used for measuring a lactonase activity of an enzyme.
Process for the preparation of alkylthioalkanoate salts
申请人:Monsanto Company
公开号:EP0245231A1
公开(公告)日:1987-11-11
A process for the preparation of alkylthioalkanoate salts by reaction of an alkali metal alkylmercaptide with a lactone in the presence of an aprotic polar organic solvent. Preferably, the alkali metal mercaptide is prepared by reaction of an alkylmercaptan and an alkali metal phenate.
Pentaerythritol co-esters derived from pentaerythritol, (3-alkyl-4-hydroxyphenyl)-alkanoic acids or an analog thereof and alkylthioalkanoic acids or lower alkyl esters of such acids are useful as stabilizers of organic material normally susceptible to oxidative and/or thermal deterioration. The co-esters are advantageously prepared by transesterification of such esters with pentaerythritol. Preferred co-esters are (I) pentaerythritol tris[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]-mono[3-n-dodecylthiopropionate] and (II) pentaerythritol bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]-bis[3-n-dodecylthiopropionate). The co-esters are especially useful in stabilizing applications for which physical mixtures of (i) (3-alkyl-4-hydroxyphenyl)alkanoic acid esters of polyols with (ii) polyalkanol esters of alkylthioalkanoic acids have heretofore been proposed.
由季戊四醇、(3-烷基-4-羟基苯基)-烷酸或其类似物以及烷硫基烷酸或此类酸的低级烷基酯衍生的季戊四醇共酯可用作通常易受氧化和/或热变质影响的有机材料的稳定剂。共酯的制备方法主要是将此类酯与季戊四醇进行酯交换反应。优选的共酯类有:(I) 季戊四醇三[3-(3,5-二叔丁基-4-羟基苯基)丙酸酯]-单[3-正十二烷基硫代丙酸酯]和 (II) 季戊四醇双[3-(3,5-二叔丁基-4-羟基苯基)丙酸酯]-双[3-正十二烷基硫代丙酸酯]。这些共酯在稳定应用方面特别有用,此前已经提出了 (i) (3- 烷基-4-羟基苯基)烷酸多元醇酯与 (ii) 烷硫基烷酸多元醇酯的物理混合物。
METHODS AND COMPOSITIONS FOR DETERMINING A LEVEL OF BIOLOGICALLY ACTIVE SERUM PARAOXONASE