Delineating Novel Metabolic Pathways of DPC 963, a Non-Nucleoside Reverse Transcriptase Inhibitor, in Rats. Characterization of Glutathione Conjugates of Postulated Oxirene and Benzoquinone Imine Intermediates by LC/MS and LC/NMR
作者:Hao Chen、John Shockcor、Weiqi Chen、Robert Espina、Liang-Shang Gan、A. E. Mutlib
DOI:10.1021/tx010153f
日期:2002.3.1
mercapturic acid conjugates excreted in the bile and urine, respectively. The structures of these adducts, which were unequivocally elucidated by LC/MS/MS and NMR experiments, revealed the existence of at least three distinct metabolic pathways leading to these products. One of the pathways, which has been described previously, involves the activation of the acetylene group after an initial hydroxylation on
通过鉴定和表征谷胱甘肽和巯基巯基乙酸,研究了(S)-5,6-二氟-4-环丙基乙炔基-4-三氟甲基-3,4-二氢-2(1H)-喹唑啉酮在大鼠中的代谢活化酸结合物分别在胆汁和尿中排泄。通过LC / MS / MS和NMR实验清楚地阐明了这些加合物的结构,揭示了存在至少三种导致这些产物的独特代谢途径。先前已描述的途径之一涉及在环丙基环的次甲基碳上初始羟基化之后,乙炔基的活化。代谢物M1被证明是通过取代的乙炔的三键酶促添加GSH后经由此途径形成的。第二种途径,如前所述 形成高反应性环氧乙烷中间体后,生成非对映异构的GSH加合物M3和M4。该假定的环氧乙烷随后重排为能够与亲核试剂(例如GSH)进行1,4-Michael加成的α,β-不饱和环丁烯酮中间体。除这些途径外,还发现DPC 963经历了以前未针对该化合物的结构类似物描述的代谢活化。假定由细胞色素P450介导的氧化脱氟导致形成假定的苯醌亚胺中间