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采用荧光淬灭法和体外无细胞ＲＮＡ合成系统研究了阿柔比星Ｂ结合ＤＮＡ和抑制ＤＮＡ依赖性ＲＮＡ合成的ＤＮＡ碱基顺序选择性。结果表明阿柔比星Ｂ与小牛胸腺ＤＮＡ，ｐｏｌｙ［ｄ（Ａ－Ｔ）］和ｐｏｌｙ［ｄ（Ｇ－Ｃ）］有明显结合；结合ＲＮＡ的活性小；与天然ＤＮＡ的结合力较与变性ＤＮＡ的结合力大。Ｓｃａｔｃｈａｒ分析显示阿柔比星Ｂ结合３种ＤＮＡ的亲和性依次为ｐｏｌｙ［ｄ（Ａ－Ｔ）］＞ｐｏｌｙ［ｄ（Ｇ－Ｃ）］＞小牛胸腺ＤＮＡ。同样，用大肠杆菌ＲＮＡ多聚酶和大鼠肝细胞核游离ＲＮＡ多聚酶实验均显示阿柔比星Ｂ的抑制力依次为ｐｏｌｙ［ｄ（Ａ－Ｔ）］＞ｐｏｌｙ［ｄ（Ｇ－Ｃ）］＞ｐｏｌｙ［ｄ（Ｉ－Ｃ）］。上述结果证明抑制ＲＮＡ合成的碱基顺序选择性与其结合ＤＮＡ碱基顺序的选择性有关
Fluorescence quenching and in vitro cell-free RNA synthesis were used to study the DNA base sequence selectivity of aclarubicin B binding to DNA and inhibition of DNA-dependent RNA synthesis. The results showed that aclarubicin B had obvious binding to calf thymus DNA, poly [d (A-T)] and poly [d (G-C)]; the activity of binding RNA was small; Denaturation of DNA binding. Scatchar analysis showed that the affinabacterin B binding to the three DNAs was in the order of poly [d (A-T)]> poly [d (G-C)]> calf thymus DNA. Similarly, both RNA polymerase and rat liver nuclear RNA polymerase showed that the inhibitory potency of aclarubicin B was poly [d (A-T)]> poly [d (G-C) d (I-C)]. The above results demonstrate that the base sequence selectivity that inhibits RNA synthesis is related to its selectivity for binding to DNA base sequences