Strekowski L, Strekowska A, Watson R A, Tanious F A, Nguyen L T, Wilson W D
J Med Chem. 1987 Aug;30(8):1415-20. doi: 10.1021/jm00391a025.
Three simple and independent tests have been introduced for studying the effect of DNA intercalating compounds on the bleomycin-mediated digestion of DNA in vitro. These methods are based on hyperchromic changes of DNA solution, changes in viscosity of DNA solution, and HPLC quantitative analysis of the four bases released from digested DNA. All three tests give comparable results. However, the viscometric method is technically the simplest and at the same time the most sensitive. The amplification of the bleomycin-mediated degradation of DNA by three unfused heteropolyaromatic intercalator molecules, namely N-[2''-(dimethylamino)ethyl]-4-thien-2'-ylpyrimidin-2-amine (1N), N,N-dimethyl-2-[(4'-thien-2''-ylpyrimidin-2'-yl)thio] ethylamine (1S), and newly synthesized 2,5-bis[2'-[[2''-(dimethylamino)ethyl]thio]pyrimidin-4'yl]thiophene (2) correlates well with the respective DNA binding constants for these compounds and is concentration dependent. The amplification activity of these compounds increases with increasing concentrations. The strongly binding compound 2 is the best amplifier of bleomycin in vitro found so far. Fused heteropolyaromatic systems, like ethidium bromide, are modest amplifiers of bleomycin at low concentrations but strongly inhibit the bleomycin chemistry at high concentrations.
为了研究DNA嵌入化合物对博来霉素体外介导的DNA消化作用的影响，已经引入了三种简单且独立的测试方法。这些方法基于DNA溶液的增色变化、DNA溶液粘度的变化以及对消化后的DNA释放的四种碱基的HPLC定量分析。所有这三种测试都给出了可比的结果。然而，粘度测定法在技术上是最简单的，同时也是最灵敏的。三种未稠合的杂多芳族嵌入剂分子，即N-[2''-(二甲氨基)乙基]-4-噻吩-2'-基嘧啶-2-胺(1N)、N,N-二甲基-2-[(4'-噻吩-2''-基嘧啶-2'-基)硫代]乙胺(1S)和新合成的2,5-双[2'-[[2''-(二甲氨基)乙基]硫代]嘧啶-4'基]噻吩(2)对博来霉素介导的DNA降解的放大作用与这些化合物各自的DNA结合常数密切相关，并且是浓度依赖性的。这些化合物的放大活性随着浓度的增加而增加。强结合化合物2是迄今为止在体外发现的博来霉素的最佳放大器。稠合的杂多芳族体系，如溴化乙锭，在低浓度时是博来霉素的适度放大器，但在高浓度时强烈抑制博来霉素的化学作用。
