Synthesis, antiproliferative evaluation, and structure–activity relationships of novel triazole–isoindoline hybrids bearing 3,4,5-trimethoxyphenyl moiety

Concise synthesis and preliminary biological evaluation of new triazolylthioacetone derivatives bearing pyridine, pyrazine, and 3,4,5-trimethoxybenzyl fragment

Based on our previous work, a series of novel triazolylthioacetones incorporating pyridine, pyrazine, and 3,4,5-trimethoxybenzyl fragment were synthesized, and evaluated for antiproliferative activities and interactions with tubulin. Some analogues exhibited moderate to excellent potency, with the most promising compound IIc possessing IC₅₀ values of 0.62, 1.46, and 3.65 μM against HT-29, HCT116, and HepG2 tumor cells, respectively, which were comparable with the positive control CA-4. Mechanistical studies revealed that IIc concentration-dependently caused cell cycle arrest at the G₂/M phase in HCT116 tumor cells, and displayed a significant inhibition of tubulin polymerization with an IC₅₀ value of 12.7 μM. Moreover, molecular docking analysis suggested that IIc could occupy the colchicine-binding site in a similar way with typical tubulinpolymerizationinhibitors. These results highlighted the 4-amino-triazolylthioacetone scaffold as potential tubulin polymerization inhibitors for development of highly efficient anticancer agents.

Synthesis and Biological Evaluation of Dithiobisacetamides as Novel Urease Inhibitors

Thirty-eight disulfides containing N-arylacetamide were designed and synthesized in an effort to develop novel urease inhibitors. Biological evaluation revealed that some of the synthetic compounds exhibited strong inhibitory potency against both cell-free urease and urease in intact cell with low cytotoxicity to mammalian cells even at concentration up to 250 μM. Of note, 2,2'-dithiobis(N-(2-fluorophenyl)acetamide) (d7), 2,2'-dithiobis(N-(3,5-difluorophenyl)acetamide) (d24), and 2,2'-dithiobis(N-(3-fluorophenyl)acetamide) (d8) were here identified as the most active inhibitors with IC₅₀ of 0.074, 0.44, and 0.81 μM, showing 32- to 355-fold higher potency than the positive control acetohydroxamic acid. These disulfides were confirmed to bind urease without covalent modification of the cysteine residue and to inhibit urease reversibly with a mixed inhibition mechanism. They also showed very good anti-Helicobacter pylori activities with d8 showing a comparable potency to the clinical used drug amoxicillin. The impressive in vitro biological profile indicated their immense potential as therapeutic agents to tackle H. pylori caused infections.

Discovery and optimization of 3,4,5-trimethoxyphenyl substituted triazolylthioacetamides as potent tubulin polymerization inhibitors

Based on our previous research, three series of new triazolylthioacetamides possessing 3,4,5-trimethoxyphenyl moiety were synthesized, and evaluated for antiproliferative activities and inhibition of tubulin polymerization. The most promising compounds 8b and 8j demonstrated more significant antiproliferative activities against MCF-7, HeLa, and HT-29 cell lines than our lead compound 6. Moreover, analogues 8f, 8j, and 8o manifested more potent antiproliferative activities against HeLa cell line with IC₅₀ values of 0.04, 0.05 and 0.16 μM, respectively, representing 100-, 82-, and 25-fold improvements of the activity compared to compound 6. Furthermore, the representative compound, 8j, was found to induce significant cell cycle arrest at the G₂/M phase in HeLa cell lines via a concentration-dependent manner. Meanwhile, compound 8b exhibited the most potent tubulin polymerization inhibitory activity with an IC₅₀ value of 5.9 μM, which was almost as active as that of CA-4 (IC₅₀ = 4.2 μM). Additionally, molecular docking analysis suggested that 8b formed stable interactions in the colchicine-binding site of tubulin.