Background: P-glycoprotein (P-gp) has been regarded as an important factor in the multidrug resistance (MDR) of tumor cells within the last decade, which can be solved by inhibiting Pgp to reverse MDR. Thus, it is an effective strategy to develop inhibitor of P-gp.

Objective: In this study, the synthesis of a series of derivatives had been carried out by bioisosterism design on the basis of Dimethyl Cardamonin (DMC). Subsequently, we evaluated their reversal activities as potential P-glycoprotein (P-gp)-mediated Multidrug Resistance (MDR) agents.

Methods: Dimethyl cardamonin derivatives were synthesized from acetophenones and the corresponding benzaldehydes in the presence of 40% KOH by Claisen-Schmidt reaction. Their cytotoxicity and reversal activities in vitro were assessed with MTT. Moreover, the compound B4 was evaluated by Doxorubicin (DOX) accumulation, Western blot and wound-healing assays deeply.

Results and Discussion: The results showed that compounds B2, B4 and B6 had the potency of MDR reversers with little intrinsic cytotoxicity. Meanwhile, these compounds also demonstrated the capability to inhibit MCF-7 and MCF-7/DOX cells migration. Besides, the most compound B4 was selected for further study, which promoted the accumulation of DOX in MCF-7/DOX cells and inhibited the expressionof P-gp at protein levels.

Conclusion: The above findings may provide new insights for the research and development of Pgp- mediated MDR reversal agents.

背景：过去十年来，P-糖蛋白（P-gp）被认为是肿瘤细胞多药耐药性（MDR）的重要因素，可以通过抑制Pgp逆转MDR来解决。因此，开发P-gp抑制剂是一种有效的策略。

目的：本研究在二甲基小豆蔻苷（DMC）的基础上，通过生物等位线设计进行了一系列衍生物的合成。随后，我们评估了它们作为潜在的P-糖蛋白（P-gp）介导的多药耐药性（MDR）药物的逆转活性。

方法：在40％KOH存在下，通过Claisen-Schmidt反应，由苯乙酮和相应的苯甲醛合成二甲基豆蔻苷衍生物。用MTT评估它们的体外细胞毒性和逆转活性。此外，通过阿霉素（DOX）积累，蛋白质印迹和伤口愈合分析对化合物B4进行了深入评估。

结果与讨论：结果表明，化合物B2，B4和B6具有MDR反向剂的效力，而固有的细胞毒性很小。同时，这些化合物还显示出抑制MCF-7和MCF-7 / DOX细胞迁移的能力。此外，选择了最多的化合物B4进行进一步的研究，它促进了DOX在MCF-7 / DOX细胞中的积累，并在蛋白质水平上抑制了P-gp的表达。

结论：以上发现可能为Pgp介导的MDR逆转剂的研究和开发提供新的见解。