Ferreira H E, Elliott W H
Faculty of Pharmacy, University of Lisbon, Portugal.
J Chromatogr. 1991 Jan 2;562(1-2):697-712. doi: 10.1016/0378-4347(91)80619-n.
Pentachlorophenyl (PCP) esters of five free bile acids (FBA) were obtained by reacting the FBA and Kovacs' complex (KC) in a 1:8 molar ratio in acetone at 65 degrees C, and were purified by column chromatography on silica gel. The esters were crystallized from benzene-hexane, derivatized as trimethylsilyl ethers for gas chromatography on a DB-1 capillary column and for gas chromatography-mass spectrometry with a DB-5 column, and mass spectrometry (MS) in the electron-impact (EI) positive-ion mode at 70 eV. The reaction is specific for FBA even in the presence of glycine and taurine conjugates of bile acids. The PCP esters were treated with benzylamine in chloroform or methanol to produce N-benzyl derivatives of FBA. The N-benzylamides were separated by high-performance liquid chromatography (HPLC) on a 4-microns Nova-Pak C18 column, studied by thermospray-LC-MS, and in the direct insertion probe-EI positive-ion mode.
通过使五种游离胆汁酸（FBA）与科瓦奇络合物（KC）以1:8的摩尔比在65℃的丙酮中反应，获得了它们的五氯苯基（PCP）酯，并通过硅胶柱色谱法进行纯化。这些酯从苯 - 己烷中结晶出来，衍生化为三甲基硅醚，用于在DB - 1毛细管柱上进行气相色谱分析以及在DB - 5柱上进行气相色谱 - 质谱联用分析，并在70eV的电子轰击（EI）正离子模式下进行质谱（MS）分析。即使在存在胆汁酸的甘氨酸和牛磺酸共轭物的情况下，该反应对FBA也是特异性的。PCP酯在氯仿或甲醇中用苄胺处理，以生成FBA的N - 苄基衍生物。N - 苄基酰胺通过在4微米的Nova - Pak C18柱上进行高效液相色谱（HPLC）分离，通过热喷雾 - LC - MS进行研究，并在直接插入探针 - EI正离子模式下进行分析。
