Curcumin is the active component of the Indian spice turmeric, known since ancient times for medicinal properties. Extensive research in the last two to three decades has confirmed its promising pharmacological properties such as anti-cancer, anti-oxidant, anti-inflammatory etc., leading to several ongoing/completed clinical trials. Curcumin has three reactive functional groups: one diketone moiety, and two phenolic groups. Curcumin interacts with several biomolecules through non-covalent and covalent binding. However, the properties limiting its potential are low bioavailability and fast degradation. The metabolites as well as degradation products of curcumin show biological activities but not as much as curcumin. To overcome these limitations, new analogues with modifications on both o-methoxy group and the diketo structures of curcumin have been developed. Of several analogues, dimethyl curcumin, where the phenolic OH is absent showed better anti-tumor activity. Also, the isoxazole and pyrazole derivatives of curcumin, derivatized at the diketo moiety have been investigated in our group. Hispolon, which is a half curcumin analogue also showed interesting cellular activity. Here in the present manuscript, the comparative cytotoxic effect of curcumin and some of these derivatives in cancer cells is presented. The results indicated that specific structural modifications on curcumin can be adopted to fine-tune its desired anticancer activity.

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姜黄素及其衍生物的重要化学结构特征：它们如何影响其抗癌活性？

姜黄素是印度香料姜黄的活性成分，自古以来就因药用而闻名。在过去的两到三十年中，广泛的研究证实了它的有希望的药理特性，例如抗癌，抗氧化，抗炎等，从而导致了一些正在进行/已完成的临床试验。姜黄素具有三个反应性官能团：一个二酮部分和两个酚基。姜黄素通过非共价和共价结合与几种生物分子相互作用。然而，限制其潜力的特性是低生物利用度和快速降解。姜黄素的代谢产物和降解产物具有生物活性，但不如姜黄素那么强。为了克服这些限制，已经开发了对邻甲氧基和姜黄素的二酮结构都进行了修饰的新类似物。在几种类似物中，缺少酚羟基的二甲基姜黄素显示出更好的抗肿瘤活性。另外，在我们的研究组中还研究了姜黄素的异恶唑和吡唑衍生物（在二酮部分衍生）。Hispolon，一种姜黄素类似物，也显示出有趣的细胞活性。在本文的此处，介绍了姜黄素和其中一些衍生物在癌细胞中的比较细胞毒性作用。结果表明，可采用姜黄素的特定结构修饰来微调其所需的抗癌活性。我们研究了姜黄素在二酮基上衍生的异恶唑和吡唑衍生物。Hispolon，一种姜黄素类似物，也显示出有趣的细胞活性。在本文的此处，介绍了姜黄素和其中一些衍生物在癌细胞中的比较细胞毒性作用。结果表明，可采用姜黄素的特定结构修饰来微调其所需的抗癌活性。我们研究了姜黄素在二酮基上衍生的异恶唑和吡唑衍生物。Hispolon，一种姜黄素类似物，也显示出有趣的细胞活性。在本文的此处，介绍了姜黄素和其中一些衍生物在癌细胞中的比较细胞毒性作用。结果表明，可以采用姜黄素的特定结构修饰来微调其所需的抗癌活性。