A library of new 3-phenylisoxazolo[5,4–d]pyrimidines (8–10) was designed based on a scaffold hybridization technique incorporating the important pharmacophoric features of 4-aminopyrimidine and phenyl isoxazole scaffold which is renowned for its BET inhibition activity. The designed molecules were synthesized and evaluated with the NCI-60 cell line panel. Examination by NCI-60 cell lines at single-dose and the five-dose study showed that compound 10h exhibited promising growth inhibitory effects with GI₅₀ values on various cancer cell lines such as HCT-15 (Colon Cancer)-0.0221 μM, MDA-MB-435 (Melanoma) − 0.0318 μM, SNB-75(CNS Cancer)-0.0263 μM, and MCF7 (Breast Cancer)-0.0372 μM. Further studies to know the mechanism of action of 10h based on the phase-contrast microscopic evaluation, DAPI, acridine orange/ethidium bromide (AO/EB) staining, and annexin V-FITC assays revealed that elevation in the intracellular ROS leads to alteration in mitochondrial membrane potential which in turn induced the apoptosis in BT-474 cancer cells, which could be the plausible mechanism of action for compound 10h.

新的3 phenylisoxazolo [5,4的文库d ]嘧啶（8 - 10）的基于结合有重要的药效的支架杂交技术设计设有4氨基嘧啶和苯基异恶唑骨架，其以其BET抑制活性。设计的分子是用 NCI-60 细胞系面板合成和评估的。NCI-60 细胞系在单剂量和五剂量研究中的检查表明，化合物10h与 GI ₅₀表现出有希望的生长抑制作用各种癌细胞系的值，例如 HCT-15（结肠癌）-0.0221 μM、MDA-MB-435（黑色素瘤）- 0.0318 μM、SNB-75（CNS 癌）-0.0263 μM 和 MCF7（乳腺癌）-0.0372微米。基于相差显微评估、DAPI、吖啶橙/溴化乙锭 (AO/EB) 染色和膜联蛋白 V-FITC 测定的进一步研究以了解10 小时的作用机制表明，细胞内 ROS 的升高导致线粒体膜电位反过来诱导 BT-474 癌细胞凋亡，这可能是化合物10h的合理作用机制。