Synthesis and biological evaluation of coumarin derivatives containing imidazole skeleton as potential antibacterial agents

Synthesis of 3-Phenylsulfonylcoumarins by Cyclisation of Phenyl Propiolates with Sulfinic Acids or Sodium Sulfinates

Methods for the synthesis of 3-phenylsulfonylcoumarins by radical sulfonylation cyclisation of phenyl propiolates with sulfinic acids or sodium sulfinates as sulfonyl sources have been developed. A combination of potassium persulfate as oxidant and silver nitrate as catalyst, or tert-butyl hydroperoxide as oxidant and potassium iodide as catalyst were used. The products were formed by an ipso-cyclisation/1,2-ester migration mechanism. The toleration of functional groups is broad and the yield is up to 96%.

Tissue regeneration promotion effects of phenanthroimidazole derivatives through pro-inflammatory pathway activation

A chemotherapeutic drug exerts favorable antitumor activity and simultaneously exhibits expectable inhibition on wound healing process. Phenanthroimidazole derivatives possess potent anticancer activity. However, only a few studies focused on the discovery of its potential effects on promoting tissue regeneration. In this study, four novel phenanthroimidazole derivatives were synthesized and characterized, and they exhibited evident inhibition on different tumor cells; compound 3 is the most active one. Moreover, 3 can promote wound healing of zebrafish in a dose-dependent manner. Further study demonstrated that 3 promoted the recruitment of inflammatory cells, formation of angiogenesis, and generation of reactive oxygen species and also influenced the motor behavior of zebrafish. Results indicated that 3 can accelerate the occurrence of pro-inflammation, angiogenesis, oxidative stress, and innervation, which play key roles in the facilitation of wound healing. Therefore, 3 can act as a bifunctional drug in inhibiting tumor and promoting tissue regeneration.

Novel coumarin-pyrazole carboxamide derivatives as potential topoisomerase II inhibitors: Design, synthesis and antibacterial activity

The identification of novel Topoisomerase II (Topo II) inhibitors is one of the most attractive directions in the field of bactericide research and development. In our ongoing efforts to pursue the class of inhibitors, six series of 70 novel coumarin-pyrazole carboxamide derivatives were designed and synthesized. As a result of the evaluation against four destructive bacteria, including Staphylococcus aureus, Listeria monocytogenes, Escherichia coli and Salmonella. Compound 8III-k (MIC = 0.25 mg/L) showed considerable inhibitory activity than ciprofloxacin (MIC = 0.5 mg/L) against Escherichia coli and 8V-c (MIC = 0.05 mg/L) exhibited excellent antibacterial activity than ciprofloxacin (MIC = 0.25 mg/L) against Salmonella. The selected compounds (8III-k, 8V-c and 8V-k) exhibit potent inhibition against Topo II and Topo IV with IC₅₀ values (9.4-25 mg/L). Molecular docking model showed that the compounds 8V-c and 8V-k can bind well to the target by interacting with amino acid residues. It will provide some valuable information for the commercial Topo II inhibiting bactericides.

Recent advances of imidazole-containing derivatives as anti-tubercular agents

Tuberculosis still remains one of the most common, communicable, and leading deadliest diseases known to mankind throughout the world. Drug-resistance in Mycobacterium tuberculosis which threatens to worsen the global tuberculosis epidemic has caused great concern in recent years. To overcome the resistance, the development of new drugs with novel mechanisms of actions is of great importance. Imidazole-containing derivatives endow with various biological properties, and some of them demonstrated excellent anti-tubercular activity. As the most emblematic example, 4-nitroimidazole delamanid has already received approval for treatment of multidrug-resistant tuberculosis infected patients. Thus, imidazole-containing derivatives have caused great interests in discovery of new anti-tubercular agents. Numerous of imidazole-containing derivatives were synthesized and screened for their in vitro and in vivo anti-mycobacterial activities against both drug-sensitive and drug-resistant Mycobacterium tuberculosis pathogens. This review aims to outline the recent advances of imidazole-containing derivatives as anti-tubercular agents, and summarize the structure-activity relationship of these derivatives. The enriched structure-activity relationship may pave the way for the further rational development of imidazole-containing derivatives as anti-tubercular agents.