We reported the synthesis of 25 derivatives of hydroxyaurone, which were characterized by 1H NMR, 13C NMR, high resolution mass spectrum, and single crystal X-ray diffraction analysis. Their activities on the death-associated protein kinase-related apoptosis-inducing kinase-2 (DRAK2) were evaluated by kinase detection kit at a dosage of 5μM. Most of the synthetic hydroxyaurones exhibited moderate to good inhibitory activities. The IC50 value ranged from 0.81 to 2.42 μM when the structure of aurone's B ring was kept unchanged and its A ring was substituted by hydroxyl groups. On the contrary, modification of the aurone's B-ring with hydroxyl groups lead to the IC50 value ranging from 1.15 to 17.5 μM. This indicates presence of hydroxyl group of the B ring is crucial for aurone's DRAK2 kinase inhibitors. Therefore, hydroxyaurone may serve as a new possible lead compound for the discovery of DRAK2. Further pharmacological investigations are underway and will be reported in due course.

中文翻译：

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羟基脲衍生物的合成、表征和 DRAK2 抑制活性

我们报道了 25 种羟基黄酮衍生物的合成，其特征在于1 H NMR、13 C NMR、高分辨率质谱和单晶 X 射线衍射分析。通过激酶检测试剂盒以5μM的剂量评估它们对死亡相关蛋白激酶相关凋亡诱导激酶2（DRAK2）的活性。大多数合成的羟基金醛酮表现出中等至良好的抑制活性。当Aurone的B环结构保持不变并且其A环被羟基取代时，IC 50值范围为0.81至2.42 μM 。相反，用羟基修饰 aurone 的 B 环导致 IC 50值范围从 1.15 到17.5 微米。这表明B 环上羟基的存在对于 aurone 的 DRAK2 激酶抑制剂至关重要。因此，羟基金黄酮可能成为发现 DRAK2 的一种新的可能先导化合物。进一步的药理学研究正在进行中，将在适当的时候报告。