We herein propose a HFIP-promoted tandem cyclization reaction for the synthesis of difluoro/trifluoromethyl carbinol-containing chromones from o-hydroxyphenyl enaminones at room temperature. This protocol provides a facile and efficient approach to access diverse difluoro/trifluoromethylated carbinols in good to excellent yields. In addition, gram-scale and synthetic derivatization experiments have also been performed.

A series of amino acid derivatives are successfully synthesized via a metal-free C–N coupling reaction of 5-alkoxy-3,4-dihalo-2(5H)-furanones and amino acids. Their structures are well characterized with ¹H NMR, ¹³C NMR, ESI-MS and elemental analysis. As potential linkers of the 2(5H)-furanone unit with other drug moieties containing a hydroxyl or amino group, the effect of amino acids is investigated by comparison with other 2(5H)-furanone compounds by constructing C–O/C–S bonds. The preliminary results of the biological activity assay by the MTT method on a series of cancer cell lines in vitro reveal that the introduction of amino acids basically has no toxic effect. This can lead to these 2(5H)-furanone derivatives being further well-linked with other bioactive moieties with amino or hydroxy groups as expected. Thus, the biological activity assay gives a direction for the design of bioactive 2(5H)-furanones based on these amino acid linkers.

The imidazo[1,2-a]pyridine skeleton is widely present in many natural products and pharmaceutical agents. Due to its impressive and significant biological activities, such as analgesic, anti-tumor, antiosteoporosis, and anxiolytic properties, the derivatization of imidazo[1,2-a]pyridine skeleton has attracted widespread attention from chemists. In recent years, significant progress has been made in the derivatization of imidazo[1,2-a]pyridines through direct C-H functionalization, especially through visible light induction. This review highlights recent advances in visible light-induced C-H functionalization of imidazo[1,2-a]pyridines during the past ten years, and some reaction mechanisms are also discussed.

Benzimidazole (BI)/triphenylamine (TPA)-based compounds (AL-1 to AL-7) were synthesized and evaluated for their cytotoxic activity in different cell lines. Among them, AL-1 demonstrated good cytotoxic activity in all the chosen cell lines, as observed from the MTT results. The antiproliferative activity of AL-1 against various cancer cells indicates that this BI-TPA-based compound may be applicable as a potential multi-cancer inhibitor. AL-1 has a low IC₅₀ value for killing H446, demonstrating the efficacy of the selected BI-TPA derivatives against highly aggressive cancer cells (H446, small cell lung cancer—SCLC). The cytotoxicity performance is correlated with the presence of two redox peaks in the cyclic voltammetry (CV) analysis. It can be found from in silico analysis that AL-1 has a good Gscore towards the mutant receptor tyrosine kinase (RTK), PDGFRα. And it has a high stability for mutant EGFR (4RJ5) in a molecular dynamics simulation study. The small binding free energy from MM-GBSA is correlated with the formation of a stable complex structure. These studies suggest that BI-TPA-based compounds (e.g., AL-1) can be used as prospective anticancer agents to treat cancer cells and their mutant variants (resistant cancer cells).

A facile and efficient method has been developed for the synthesis of C3-difluoromethyl carbinol-containing imidazo[1,2-a]pyridines at room temperature via the HFIP-promoted Friedel–Crafts reaction of difluoroacetaldehyde ethyl hemiacetal and imidazo[1,2-a]pyridines. This strategy could be applied to the direct C(sp²)-H hydroxydifluoromethylation of imidazo[1,2-a]pyridines and afford a series of novel difluoromethylated carbinols in good to satisfactory yields with 29 examples. Furthermore, gram-scale and synthetic transformation experiments have also been achieved, demonstrating its potential applicable value in organic synthesis. This green protocol has several advantages, including being transition metal- and oxidant-free, being carried out at room temperature, having high efficiency, and having a wide substrate scope.