The monocyclic 1,4-benzoquinone, HU-331, the direct oxidation product of cannabidiol, inhibits the catalytic activity of topoisomerase II but without inducing DNA strand breaks or generating free radicals, and unlike many fused-ring quinones exhibits minimal cardiotoxicity. Thus, monocyclic quinones have potential as anticancer agents, and investigation of the structural origins of their biological activity is warranted. New syntheses of cannabidiol and (±)-HU-331 are here reported. Integrated synthetic protocols afforded a wide range of polysubstituted resorcinol derivatives; many of the corresponding novel 2-hydroxy-1,4-benzoquinone derivatives are potent inhibitors of the catalytic activity of topoisomerase II, some more so than HU-331, whose monoterpene unit replaced by a 3-cycloalkyl unit conferred increased antiproliferative properties in cell lines with IC50 values extending below 1 mM, and greater stability in solution than HU-331. The principal pharmacophore of quinones related to HU-331 was identified. Selected monocyclic quinones show potential for the development of new anticancer agents.

中文翻译：

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单环醌结构活性模式：拓扑异构酶II具有强抗增殖活性的催化抑制剂的合成。

大麻二酚的直接氧化产物单环1,4-苯醌HU-331抑制拓扑异构酶II的催化活性，但不诱导DNA链断裂或产生自由基，与许多稠环醌不同，其心脏毒性最小。因此，单环醌具有作为抗癌剂的潜力，因此有必要对其生物学活性的结构来源进行研究。本文报道了大麻二酚和（±）-HU-331的新合成。集成的合成方案提供了多种多取代的间苯二酚衍生物。许多相应的新型2-羟基-1,4-苯醌衍生物是拓扑异构酶II催化活性的有效抑制剂，比HU-331更重要，其单萜单元被3-环烷基单元取代后，其细胞系的抗增殖特性增强，IC50值延伸至1 mM以下，并且溶液的稳定性高于HU-331。确定了与HU-331相关的醌类主要药效基团。选定的单环醌显示出开发新的抗癌药的潜力。