Synthesis, molecular docking analysis and in vitro evaluation of new heterocyclic hybrids of 4-aza-podophyllotoxin as potent cytotoxic agents

Plant Origin Source, Content Profile and Bioactivity of Podophyllotoxin as an Important Natural Anticancer Agent

Pharmacological studies have shown that podophyllotoxin (PTOX) has anti-tumor, antiviral, and anti-inflammatory effects. More and more derivatives of PTOX, such as VM-26, NK-611 and GL-331, have gradually been synthesized and are widely used in clinical practice. Sinopodophyllum hexandrum rhizome is rich in PTOX, which is much higher than other PTOX source plants. At present, research on S. hexandrum mainly focuses on artificial cultivation, chemical composition, pharmaceutical value, and the biosynthesis pathway of PTOX. However, the researches are relatively scattered, and systematic review on PTOX is very limited. Therefore, this study performed a comprehensive investigation of the plant origin source, content profile, and biological activities to provide an integrated reference for in-depth research and clinical application of PTOX in the fields of chemistry and pharmacy, which can promote the innovative use of S. hexandrum resources and research and development of new anticancer drugs.

Novel zerumbone-secondary amide hybrids: ultrasonic synthesis, cytotoxic evaluation, molecular docking and in silico ADMET studies

Zerumbone, along with its various derivatives and structurally related compounds, has attracted significant scientific interest due to its broad-spectrum pharmacological properties, particularly its anticancer potential. In this study, novel zerumbone-secondary amide hybrids were successfully designed and synthesized with high yields using both conventional and ultrasonic methods. Reactions performed under ultrasonic conditions required significantly shorter reaction times than those conducted without ultrasound while maintaining comparable product yields. The cytotoxicity of the synthesized derivatives was evaluated against four human cancer cell lines: hepatocellular carcinoma (HepG2), lung carcinoma (A549), acute leukemia (HL-60), and gastric carcinoma (AGS). Most derivatives exhibited significant cytotoxic activity, with those derived from azazerumbone 2 demonstrating greater potency than those derived from azazerumbone 1. The incorporation of secondary amide groups has been confirmed to enhance the cytotoxic activity of the newly synthesized derivatives against cancer cells. Notably, compounds 4c, 4g, and 4i displayed the strongest cytotoxicity across all tested cell lines, with IC50 values ranging from 0.81 ± 0.04 to 4.14 ± 0.44 μg mL-1, comparable to those of zerumbone and ellipticine. Docking studies revealed a strong correlation between the biological activity of zerumbone-secondary amide hybrids and their binding affinity to EGFR tyrosine kinase, further highlighting the crucial role of secondary amide groups in enhancing their anticancer potential. Furthermore, pharmacokinetic predictions indicate that compounds 4c, 4g, and 4i possess favorable drug-like properties, reinforcing their potential as lead candidates for anticancer drug development.

Synthesis, cytotoxicity, apoptosis-inducing activity and molecular docking studies of novel isatin-podophyllotoxin hybrids

Podophyllotoxin, along with its numerous derivatives and related compounds, is well known for its broad-spectrum pharmacological activity, especially for anticancer potential. In this study, several isatin-podophyllotoxin hybrid compounds were successfully synthesized with good yields through microwave-prompted three-component reactions of 2-amino-1,4-naphthoquinone, various substituted isatins, and tetronic acid. Their cytotoxicity was assessed against four types of human cancer cell lines, HepG2 (hepatoma carcinoma), MCF7 (breast cancer), A549 (non-small lung cancer), and KB (epidermoid carcinoma), alongside nontumorigenic HEK-293 human embryonic kidney cells. Among 14 compounds screened, 7f possessed the strongest cytotoxicity to KB and A549 cell lines, with IC50 values of 1.99 ± 0.22 and 0.90 ± 0.09 μM, respectively. Further studies revealed that product 7f could arrest the cell cycle of A549 cells at S phase and induce apoptosis of A549 cells. This compound was examined for its binding ability against cyclin-dependent kinases (CDKs) and procaspase/caspase systems. The results indicated that 7f exhibited significant interactions with the residues of the ATP binding sites of CDK2/cyclin A and CDK5/p25 and also activated procaspase 6 through stable zinc chelation. Additionally, physicochemical and pharmacokinetic properties related to drug-likeness, in parallel with toxicity, were computationally assessed to identify the main issues that need to be addressed in structural optimization. Taken together, compound 7f was identified as a potent cytotoxic agent that could be considered for anticancer drug discovery and development.

Improved synthesis, molecular modeling and anti-inflammatory activity of new fluorinated dihydrofurano-naphthoquinone compounds

A series of new fluorinated dihydrofurano-napthoquinone compounds were sucessfully synthesized in good yields using microwave-assisted multi-component reactions of 2-hydroxy-1,4-naphthoquinone, fluorinated aromatic aldehydes, and pyridinium bromide. The products were fully characterized using spectroscopic techniques and evaluated for their anti-inflammatory activity using lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells. Among 12 new compounds, compounds 8b, 8d, and 8e showed high potent NO inhibitory activity in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophage cells with IC50 values ranging from 1.54 to 3.92 µM. The levels of pro-inflammatory cytokines IL-1β and IL-6 in LPS-stimulated RAW264.7 macrophages were remarkably decreased after the application of 8b, 8d, 8e and 8k. Molecular docking simulations revealed structure-activity relationships of 8b, 8d, and 8e toward NO synthase, cyclooxygenase (COX-2 over COX-1), and prostaglandin E synthase-1 (mPGES-1). Further physicochemical and pharmacokinetic computations also demonstrated the drug-like characteristics of synthesized compounds. These findings demonstrated the importance of fluorinated dihydrofurano-napthoquinone moieties in the development of potential anti-inflammatory agents.