3-Formylchromones in Guareschi Synthesis of 5-(2-hydroxybenzoyl)-2-pyridones
作者:Dmitriy M. Volochnyuk、Sergey V. Ryabukhin、Andrey S. Plaskon、Andrey A. Tolmachev
DOI:10.1055/s-2004-832852
日期:——
A set of 5-(2-hydroxybenzoyl)-pyrid-2-ones, which are analogous to cardiotonic drugs such as milrinone, has been prepared in high yield by recyclization of 3-formylchromones with acetic acid amides having at the α-position an electron-withdrawing group. The best reaction conditions were found to be heating in DMF in the presence of Me3SiCl as a promoter and water scavenger.
A Pyridinium Derivatization Reagent for Highly Sensitive Detection of Poly(carboxylic acid)s Using Liquid Chromatography-Electrospray Ionization-Tandem Mass Spectrometry
polarity of their carboxyl groups. Various derivatization methods have been developed; however, most are effective only for monocarboxylic acids and not for those having multiple carboxyl groups. Therefore, we successfully attempted to synthesize a derivatization reagent that could analyze both mono- and poly(carboxylic acid)s with high sensitivity. We optimized our derivatization reagent by modifying the
由于其羧基的高极性,短链脂肪酸难以使用液相色谱-电喷雾电离-质谱 (LC-ESI-MS) 进行高灵敏度分析。已经开发了各种衍生化方法;然而,大多数仅对一元羧酸有效,而对具有多个羧基的那些无效。因此,我们成功地尝试合成一种衍生化试剂,该试剂可以以高灵敏度分析单和聚(羧酸)。我们通过修改反应位点的结构、衍生化合物的疏水性以及将反应位点连接到永久带电子结构的接头结构来优化我们的衍生化试剂。通过使用哌啶部分作为反应位点,提高了对羧基的反应性,高疏水性和永久带电的三苯基吡啶鎓基团提高了 ESI 效率。此外,烷基接头的加入使多标记成为可能。当优化的试剂应用于单、二、三和四羧酸时,ESI 效率随着多标记而增加;因此,我们的衍生化试剂优于现有的衍生化方法,并且能够以高灵敏度分析聚(羧酸)。由于该衍生试剂可应用于大多数含羧基化合物,因此可广泛用于脂质组学、蛋白质组学和代谢组学。三羧酸和四羧酸,ESI 效率随
Non-toxic corrosion-protection pigments based on manganese
申请人:——
公开号:US20040011252A1
公开(公告)日:2004-01-22
Corrosion-inhibiting pigments based on manganese are described that contain a trivalent or tetravalent manganese/valence stabilizer complex. An inorganic or organic material is used to stabilize the trivalent or tetravalent manganese ion to form a compound that is sparingly soluble, exhibits low solubility, or is insoluble in water, depending upon the intended usage. Specific stabilizers are chosen to control the release rate of trivalent or tetravalent manganese during exposure to water and to tailor the compatibility of the powder when used as a pigment in a chosen binder system. Stabilizers may also modify the processing and handling characteristics of the formed powders. Manganese/valence stabilizer combinations are chosen based on the well-founded principles of manganese coordination chemistry. Many manganese-valence stabilizer combinations are presented that can equal the performance of conventional hexavalent chromium or tetravalent lead systems. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.
Non-toxic corrosion-protection pigments based on rare earth elements
申请人:——
公开号:US20040104377A1
公开(公告)日:2004-06-03
A corrosion-inhibiting pigment comprising a rare earth element and a valence stabilizer combinded to form a rare earth/valence stabilizer complex. The rare earth element is selected from cerium, terbium, praseodymium, or a combination thereof, and at least one rare earth element is in the tetravalent oxidation state. An inorganic or organic material is used to stabilize the tetravalent rare earth ion to form a compound that is sparingly soluble in water. Specific stabilizers are chosen to control the release rate of tetravalent cerium, terbium, or praseodymium during exposure to water and to tailor the compatibility of the powder when used as a pigment in a chosen binder system. Stabilizers may also modify the processing and handling characteristics of the formed powders. Many rare earth-valence stabilizer combinations are presented that can equal the performance of conventional hexavalent chromium systems.