A number of novel furo[2,3‐b]quinoline derivatives were designed and synthesized by introducing benzyl ether, benzoate, and benzenesulfonate to 6‐position of furo[2,3‐b]quinoline and their chemical structures were confirmed by ESI‐MS, ¹H NMR, and ¹³C NMR spectra. All target compounds were evaluated in vitro against four human cancer cell lines (HCT‐116, MCF‐7, U2OS, and A549) by MTT method. Cytotoxic assay showed that compounds 8a, 8e, 10a, 10b, and 10c exhibited more potent cytotoxicities compared to 2‐bromine‐6‐hydroxy‐furo‐[2,3‐b]quinoline (7). Compound 10c exhibited higher antiproliferative activity (IC₅₀ values ranging from 4.32 to 24.96 μm) against four human cancer cell lines (HCT‐116, MCF‐7, U2OS, and A549) and weak cytotoxicity on normal cell HL‐7702, which suggested that 10c might be an ideal anticancer candidate. Compounds 8a, 10a, 10b showed good selectivities to MCF‐7 and HCT‐116, which could be considered as ideal selective candidates for further study. The SARs showed that the introduction of the benzyl ether and benzenesulfonate could significantly improve cytotoxicities, while the benzoate failed to enhance potency obviously.

中文翻译：

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新型呋喃并[2,3-b]喹啉衍生物的设计，合成和细胞毒性评估

通过将苄基醚，苯甲酸酯和苯磺酸酯引入到呋喃[2,3-b]喹啉的6-位上，设计并合成了许多新型呋喃[2,3-b]喹啉衍生物，并通过ESI-化学结构证实了它们的化学结构。 MS，¹ H NMR和¹³ C NMR光谱。通过MTT方法在体外针对四种人类癌细胞系（HCT-116，MCF-7，U2OS和A549）评估了所有目标化合物。细胞毒性试验表明，与2-溴-6-羟基-呋喃基[2,3-b]喹啉相比，化合物8a，8e，10a，10b和10c表现出更强的细胞毒性（7）。化合物10c表现出更高的抗增殖活性（IC _50个值范围为4.32至24.96μ米）针对四种人类肿瘤细胞系（HCT-116，MCF-7，U2OS，和A549）和弱的细胞毒性对正常细胞HL-7702，提示10c中可能是理想的抗癌候选药物。化合物8a，10a，10b对MCF-7和HCT-116表现出良好的选择性，可以认为是进一步研究的理想选择性候选物。SARs表明，引入苄基醚和苯磺酸盐可以显着改善细胞毒性，而苯甲酸盐却不能显着增强药效。