Abstract Flavonoids are widely occurring polyphenols of plant origin and well explored in the field of pharmacological activities. Recent studies showed this scaffold to be more dynamic as fluorescent probe. Very rare reports are there in literature on flavones as liquid crystals, for the first time we have synthesized and characterized flavone and bis-flavone derivatives for mesomorphic properties. Compounds 9a–d and 13a–d were studied for liquid crystalline properties by Differential scanning calorimetry (DSC) and Polarizing optical microscopy (POM) studies. The compounds 8, 9a–d, 12, and 13a–d were also studied for antioxidant property by DPPH assay. Graphical abstract We have synthesized new n-alkoxy flavone and Bis-flavone derivatives for liquid crystalline properties. The compounds were characterized by using different spectral techniques, all synthesized compounds did not show mesophase which was confirmed by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM) study. POM image of compound 9c in heating (a) shows direct melting (92.2°C) of compound and cooling (b) goes to crystallization (65.8°C) with no phase. Flavone derivatives are well reported to show broad pharmacological applications, we have also tested compounds for antioxidant properties by DPPH assay.

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黄酮及双黄酮衍生物的合成与研究

摘要 黄酮类化合物是广泛存在的植物多酚，在药理活性领域得到了很好的探索。最近的研究表明，这种支架作为荧光探针更具活力。文献中关于黄酮作为液晶的报道非常罕见，这是我们第一次合成并表征了黄酮和双黄酮衍生物的介晶特性。通过差示扫描量热法 (DSC) 和偏光显微镜 (POM) 研究化合物 9a-d 和 13a-d 的液晶特性。还通过 DPPH 测定研究了化合物 8、9a-d、12 和 13a-d 的抗氧化性能。图形摘要 我们已经合成了具有液晶特性的新型正烷氧基黄酮和双黄酮衍生物。通过使用不同的光谱技术对化合物进行表征，所有合成的化合物都没有显示出中间相，这通过差示扫描量热法 (DSC) 和偏光显微镜 (POM) 研究得到证实。加热 (a) 中化合物 9c 的 POM 图像显示化合物直接熔化 (92.2°C)，冷却 (b) 结晶（65.8°C）而无相。据报道，黄酮衍生物显示出广泛的药理学应用，我们还通过 DPPH 测定测试了化合物的抗氧化特性。