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A novel two-component cyclization toward the synthesis of polysubstituted 4,5-dihydropyrazoles was carried out: i.e., cyclization of β,γ-unsaturated hydrazones with aryl iodides catalyzed by Pd(0). The reaction forms new carbon–carbon bonds and carbon–nitrogen bonds with moderate to good reactivity.

A series of novel pleuromutilin derivatives with substituted thienopyrimidines were designed, synthesized, and evaluated for antibacterial act ivity. In this study, the activities of these compounds were investigated using the inhibition circle test, the minimum inhibitory concentration (MIC) test, real-time growth curves, time-kill kinetic assays, cytotoxicity assays, and molecular docking. Most of the tested compounds exhibited moderate antibacterial activity against Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli. Compound A11 was the most active and displayed bacteriostatic activities against methicillin-resistant S. aureus, with MIC values as low as 0.00191 μg/mL, which is 162 and 32 times lower than that of the marketed antibiotics tiamulin and retapamulin, respectively. Furthermore, the mechanism of action of A11 was confirmed by molecular docking studies.

To resolve the problem of drug resistance caused by epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer, we used the principle of collocation to design and synthesize a series of aminopyrimidine derivatives with 4,5,6,7-tetrahydrothieno [3,2-c]pyridine side chains (according to the binding mode of AZD9291 to EGFRT790M) for use as EGFRL858R/T790M kinase inhibitors. The most promising compound A12, a non-covalently bound reversible inhibitor, showed excellent kinase inhibitory activity against EGFRL858R/T790M, with an IC50 value of 4.0 nM and more than 42-fold selectivity for EGFRWT (IC50 = 170.0 nM). Moreover, compound A12 showed strong anti-proliferative activity against H1975 cells, with IC50 value of 0.086 μΜ. Additionally, the effective inhibition of cell migration and the promotion of apoptosis by A12 verified its mechanism of action, as a selective inhibitor of EGFRL858R/T790M.

Artificial light at night (ALAN/A) can not only alter the behavior and communication of biological organisms, it can also interact with other stressors. Despite its widespread use and the numerous potential ecological effects, little is known about the impact of ALAN on plant litter decomposition under cadmium (Cd) pollution in aquatic ecosystems. In an indoor microcosm experiment, we tested single and combined effects of ALAN and Cd on the activities and community structure of fungi associated with plant litter. The results showed that ALAN and/or Cd can change both water and leaf litter characteristics. ALAN exposure not only altered fungal community structure and their correlations, but also increased the activities of alkaline phosphatase, &beta, glucosidase, and cellobiohydrolase. The leaf litter decomposition rate was 71% higher in the A-Cd treatment than that in the N-Cd treatment, indicating that the presence of ALAN weakened the negative impact of Cd on leaf litter decomposition. These results suggested that ALAN exposure mitigated the negative effect of Cd on leaf litter decomposition, contributing to the duel effect of ALAN on leaf litter decomposition. Overall, the results expand our understanding of ALAN on the environment and highlight the contribution of ALAN to Cd toxicity in aquatic ecosystems.