Identification of Tamoxifen−DNA Adducts Formed by α-Sulfate Tamoxifen and α-Acetoxytamoxifen
作者:Lakkaraju Dasaradhi、Shinya Shibutani
DOI:10.1021/tx960114h
日期:1997.2.1
were synthesized as proposed active metabolites of tamoxifen that react with DNA. alpha-Acetoxytamoxifen was prepared as a model-activated form to produce a reactive carbocation. Calf thymus DNA was reacted with alpha-hydroxytamoxifen or the activated forms of tamoxifen, and tamoxifen-DNA adducts were analyzed by a 32P-postlabeling method. The reactivity of alpha-sulfate trans-tamoxifen to DNA was much
合成了α-硫酸盐反式他莫昔芬和α-硫酸盐顺他莫昔芬,作为他莫昔芬与DNA反应的活性代谢产物。将α-乙酰氧他莫昔芬制备为模型激活形式,以产生反应性碳正离子化。小牛胸腺DNA与α-羟基他莫昔芬或他莫昔芬的活化形式反应,并通过32P后标记法分析他莫昔芬-DNA加合物。α-硫酸反式他莫昔芬对DNA的反应性比α-羟基他莫昔芬的反应性高得多。由α-乙酰氧基他莫昔芬和α-硫酸盐顺式他莫昔芬诱导的他莫昔芬-DNA加合物的形成分别比α-羟基他莫昔芬高1100倍和1600倍。α-硫酸他莫昔芬和α-乙酰氧基他莫昔芬均对2'-脱氧鸟苷具有高反应性。HPLC分离了dG-他莫昔芬的四种反应产物,并通过质子和质子磁共振波谱进行了表征。首先洗脱的馏分1和2被鉴定为dG-N2-他莫昔芬反式的差向异构体。馏分3和4被鉴定为dG-N2-他莫昔芬的顺式差向异构体。当DNA与α-乙酰氧基他莫昔芬体外反应时,检测到dG-N2-他莫昔