Novel 1H-purin-6(9H)-one (D) and 3H-imidazo[4,5-d][1,2,3]trazin-4(7H)-one (E) derivatives were designed, synthesized, and characterized by ¹H NMR, ¹³C NMR and high-resolution mass spectrometry spectra. Their herbicidal activity bioassay showed that compound 7d exhibited relatively good activity with 70.4% inhibition rate against Amaranthus retroflexus in postemergence treatments at 1500 g/ha. Antitumor activity indicated that most of the title compounds displayed potent antitumor activity at 20 μM, among all of the promising compounds possessing lower IC₅₀ values than that of temozolomide, compound 7i demonstrated highest activity inhibiting both HepG-2 and U-118 MG cell lines with IC₅₀ values of 2.0 and 3.8 μM, respectively. The structure–activity relationship analysis revealed that introduction of halogen atoms, a bulky bridging bond between benzene ring and nitrogen atom, longer R² substituents could contribute to the improvement of antitumor activity. Analysis suggested that compound 7i might have potential as new highly active antitumor agent. Overall, D series had better anticancer activities than E series derivatives.

中文翻译：

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新型1 H -Purin-6（9 H）-one和3 H-咪唑并[4,5- d ] [1,2,3] triazin-4（7 H）-one衍生物的合成及活性研究

设计了新型的1 H-嘌呤-6（9 H）-one（D）和3 H-咪唑并[4,5- d ] [1,2,3] trazin-4（7 H）-one（E）衍生物。 ，合成并通过¹ H NMR，¹³ C NMR和高分辨率质谱图进行表征。他们的除草活性生物测定表明，在1500 g / ha的芽后处理中，化合物7d表现出相对较好的活性，对逆A菜具有70.4％的抑制率。抗肿瘤活性表明，大多数标题化合物在20μM时均显示出强大的抗肿瘤活性，而所有有前途的化合物均具有较低的IC。与替莫唑胺相比，化合物7i的₅₀值最高，其抑制HepG-2和U-118 MG细胞系的活性最高，IC ₅₀值分别为2.0和3.8μM。结构-活性关系分析表明，引入卤素原子，苯环与氮原子之间的巨大桥键，较长的R ²取代基可有助于提高抗肿瘤活性。分析表明，化合物7i可能具有作为新型高活性抗肿瘤药的潜力。总体而言，D系列具有比E系列衍生物更好的抗癌活性。