Wang K, Bermúdez E, Pryor W A
Biodynamics Institute, Louisiana State University, Baton Rouge 70803-1800.
Steroids. 1993 May;58(5):225-9. doi: 10.1016/0039-128x(93)90023-g.
The ozonation products of cholesterol, which are of interest as possible biomarkers of O3 exposure, were studied by derivatization with 2,4-dinitrophenylhydrazine (DNPH). The DNPH derivatization of 3 beta-hydroxy-5-oxo-5,6-secocholestan-6-al (2) produces the expected trans (3b) and cis (3c) derivatives of 3 beta-hydroxy-5-oxo-5,6-secocholestan-6-al, and the unexpected DNPH derivative of 3,5-dihydroxy-B-norcholestane-6-carboxaldehyde (3a). The structures of 3a, 3b, and 3c were identified with 1H nuclear magnetic resonance (NMR), 13C NMR, DEPT, COSY, and H-C correlation two-dimensional NMR techniques, and by comparison with the spectra of known compounds. A possible mechanism involving an enamine functionality is proposed for the formation of 3a. The ratio of 3a/(3b + 3c) depends on the concentration of acid used and the reaction time.
通过用2,4 - 二硝基苯肼（DNPH）衍生化来研究胆固醇的臭氧化产物，这些产物作为臭氧暴露的可能生物标志物具有研究价值。3β - 羟基 - 5 - 氧代 - 5,6 - 断胆甾烷 - 6 - 醛（2）的DNPH衍生化产生了预期的3β - 羟基 - 5 - 氧代 - 5,6 - 断胆甾烷 - 6 - 醛的反式（3b）和顺式（3c）衍生物，以及意外的3,5 - 二羟基 - B - 降胆甾烷 - 6 - 甲醛（3a）的DNPH衍生物。通过1H核磁共振（NMR）、13C NMR、DEPT、COSY和H - C相关二维NMR技术，并与已知化合物的光谱进行比较，确定了3a、3b和3c的结构。提出了一种涉及烯胺官能团的可能机制来解释3a的形成。3a/(3b + 3c)的比例取决于所用酸的浓度和反应时间。
