The rise of drug-resistant tuberculosis (TB) has created an urgent need to discover and develop new anti-mycobacterial agents. Herein, we report the synthesis and evaluation of a library of 1,3-diaryl substituted pyrazole-based imidazo[1,2-a]pyridine carboxamides as promising anti-TB agents. In preliminary screening, 10 out of 26 compounds displayed potent in vitro inhibition against Mtb H37Rv with a MIC value of 0.03 μg/mL, which is 17-fold more potent than the first-line TB drug streptomycin, 33-fold more potent than ethambutol, and equipotent with isoniazid and rifampicin. Encouragingly, most of these compounds exhibited a selectivity index (SI) >3333.3 and CC₅₀ values >100 μg/mL against Vero cells, indicating they are over 3000 times more toxic to M. tuberculosis than to mammalian cells and demonstrate absence of cytotoxicity at concentrations effective against TB (MIC = 0.03 μg/mL). Among them, 12a, 14a, and 14d demonstrated remarkable activity against drug-resistant strains of Mtb with an MIC of 0.03 μM. Time-kill kinetic studies revealed that 12a, 14a, and 14d exhibited bacteriostatic properties. Furthermore, 12a, 14a, and 14d demonstrated synergistic effects with the FDA-approved anti-TB drugs rifampicin (ƩFIC 0.093), ethambutol (ƩFIC 0.061), and moxifloxacin (ƩFIC 0.154-0.281), exhibiting bactericidal time-kill properties in combination with these drugs. Additionally, 12a, 14a, and 14d exhibited acceptable metabolic stability (CLint 11.49-14.62 μL/min/mg microsomal protein), indicating effective drug levels and bioavailability. Also, 12a, 14a, and 14d showed stable interactions with QcrB in docking studies. These findings highlight 12a, 14a, and 14d as potential candidates for in vivo evaluation and further development as novel anti-tubercular drugs.
Bromodomain-containing protein 4 (BRD4), a crucial epigenetic regulator in cancer, has become a critical target for melanoma therapy. Herein, we investigated a strategy for enhancing the antiproliferative activity of BRD4 inhibitors against melanoma cells. A compound that exhibits antitumor effects in a mouse melanoma xenograft model at doses lower than those required for previously reported compound 1 is required. Therefore, we focused on enhancing the antiproliferative activity of BRD4 inhibitors against melanoma cells. Our hypothesis state that mitigating P-glycoprotein (P-gp) substrate recognition can improve cell permeability and enhance cellular inhibitory activity. Thus, we reduced the hydrogen-bond donors (HBDs) of a benzimidazole core through N-alkylation. Using this approach, we successfully enhanced the cellular inhibitory activity by mitigating P-gp substrate recognition; however, the compounds derived from this approach exhibited poor metabolic stability. To overcome this issue, we used a scaffold-hopping strategy to identify core-lacking HBDs and discovered the imidazopyridine derivative 17. This compound exhibits potent antiproliferative activity against melanoma cells and good oral exposure. Thus, we conclude that mitigation of P-gp substrate recognition can effectively enhance cellular activity and identify favorable antitumor agents.
Aging is a progressive degenerative state characterized by a gradual loss of physiological fitness, resulting in deteriorated functions and susceptibility to age-related diseases. With the progress of research on aging and age-related mechanisms, identifying effective anti-aging drugs has become a key focus. In this review, we summarize aging and its related signaling pathways and targets, mainly including clearance of senescent cells, NAD+ augmentation, anti-inflammatory and anti-oxidant defense, dysfunction of proteostasis and activation of telomerase. Furthermore, we collect advanced research progress of anti-aging agents and other strategies to delay aging and age-related diseases, and ultimately ameliorate lifespan and healthspan. Finally, we review anti-aging research and discuss potential strategies for aging intervention.
The exploitation of glycans as targeting agents to construct delivery materials has proved useful for targeted disease diagnosis and therapy. To achieve effective targeting, multivalent glycosides are prepared to enhance avidity with sugar receptors. In this study, we designed and synthesized a new trivalent mannoside (Man3-PEG3-N3) bearing an azido unit. This azido mannosyl glycocluster was used to conjugate with cyclooctyne-modified human serum albumin (HSA) through strain-promoted click chemistry. Mass spectroscopic analysis validated the successful construction of the glycocluster-conjugated HSA, and a fluorescence titration assay indicated that the resulting conjugate is capable of accommodating an environmentally sensitive dye.

