Inhibiting tyrosyl-DNA phosphodiesterase 1 (TDP1) is a promising strategy for increasing the effectiveness of existing antitumor therapy since it can remove the DNA lesions caused by anticancer drugs, which form covalent complexes with topoisomerase 1 (TOP1). Here, new adamantane–monoterpene conjugates with a 1,2,4-triazole or 1,3,4-thiadiazole linker core were synthesized, where (+)-and (−)-campholenic and (+)-camphor derivatives were used as monoterpene fragments. The campholenic derivatives 14a–14b and 15a–b showed activity against TDP1 at a low micromolar range with IC50 ~5–6 μM, whereas camphor-containing compounds 16 and 17 were ineffective. Surprisingly, all the compounds synthesized demonstrated a clear synergy with topotecan, a TOP1 poison, regardless of their ability to inhibit TDP1. These findings imply that different pathways of enhancing topotecan toxicity other than the inhibition of TDP1 can be realized.
抑制酪氨酸-DNA磷酸二酯酶1(TDP1)是一种增加现有抗肿瘤治疗效果的有希望的策略,因为它可以去除由抗癌药物引起的DNA损伤,这些损伤与拓扑异构酶1(TOP1)形成共价复合物。在这里,合成了具有1,2,4-三唑或1,3,4-噻二唑连接核心的新的金刚烷-单萜共轭物,其中使用了(+)-和(-)-香叶烯和(+)-薄荷醇衍生物作为单萜片段。香叶烯衍生物14a-14b和15a-b在低微摩尔范围内对TDP1表现出活性,IC50约为5-6μM,而含薄荷醇的化合物16和17则无效。令人惊讶的是,所有合成的化合物都表现出与TOP1毒素拓扑替诺酮的明显协同作用,无论它们是否能抑制TDP1。这些发现意味着可以实现除抑制TDP1之外的不同途径来增强拓扑替诺酮的毒性。