In this study, a series of novel tryptanthrin derivatives were synthesized and their inhibitory activities against selected human cancer cell lines, namely, lung (A549), chronic myeloid leukemia (K562), prostate (PC3), and live (HepG2), were evaluated using a methyl thiazolyl tetrazolium colorimetric (MTT) assay. Among the tested compounds, compound C1 exhibited a promising inhibitory effect on the A549 cell line with an IC₅₀ value of 0.55 ± 0.33 µM. The observation of the cell morphological result showed that treatment with C1 could significantly inhibit the migration of A549 cells through the cell migration assay. Moreover, after treatment with C1, the A549 cells exhibited a typical apoptotic morphology and obvious autophagy. In addition, the detection of apoptosis and the mitochondrial membrane potential indicated that C1 induced A549 cell apoptosis via modulating the levels of Bcl2 family members and disrupted the mitochondrial membrane potential. Compound C1 also suppressed the expression of cyclin D1 and increased the expression of p21 in the A549 cells, inducing cell cycle arrest in the G2/M phase in a dose dependent manner. The further mechanism study found that C1 markedly increased the transformation from LC3-I to LC3-II. Taken together, our results suggest that C1 is capable of inhibiting the proliferation of non-small cell lung cancer (NSCLC) cells, inducing cell apoptosis, and triggering autophagy.

Herein, a new series of 2-chloro-N-(5-(2-oxoindolin-3-yl)-4H-pyrazol-3-yl) acetamide derivatives containing 1,3,4-thiadiazole (10a–i) and 4H-1,2,4-triazol-4-amine (11a–r) moiety was designed, synthesised as novel anticancer agents. The antiproliferative activity values indicated that compound 10 b stood as the most potent derivative with IC₅₀ values of 12.0 nM and 10 nM against A549 and K562 cells, respectively. Mechanism investigation and docking studies of 10 b indicated that it possessed good apoptosis characteristic and dose-dependent growth arrest of A549 and K562 cells, blocked cell cycle into G2/M phase. Interestingly, 10 b suppressed the growth of A549 and K562 cells via modulation of EGFR and p53-MDM2 mediated pathway.

In this study, three series of quinazolinone derivatives containing hydrazone structures were designed and synthesized. Bioactivity assays indicated that these compounds showed good antitumour activities towards human lung cancer cells (A549) and human prostate cancer cells (PC-3) and no apparent toxicity towards those nontumorigenic rat renal tubular epithelial cells (NRK-52E). In particular, compound 7n showed potent inhibitory activity towards A549 and PC-3 with IC₅₀ of 7.36 and 7.73 μmol L⁻¹, respectively. Subsequently, the relationships between the compound structures and numerous biological activities are discussed. A good predictive three-dimensional quantitative structure–activity relationship (3D-QSAR) model was constructed via CoMFA to direct the future structural units. The present results strongly show that 7n with the introduction of 2-fluorobenzoyl should be considered as a lead compound to develop novel antitumour agents.