Search Results (6)

The authors previously reported that 2-methylbenzimidazole derivatives (MBIs) exhibit insect growth-regulating activity against the silkworm, Bombyx mori. However, despite their unique effects on juvenile hormone (JH)-related endocrine pathways, the precise mode of action of MBIs remained unclear. In the present study, the interactions between MBIs and the lepidopteran hemolymph JH-binding protein (JHBP), a key regulator of JH transport and activity, were investigated using multiple approaches, including in vitro binding affinity assays, X-ray crystallography, and molecular docking simulations. A series of MBIs bearing a 1-(4-alkoxybenzyl) group, which exhibited potent insect growth-regulating activity, showed high binding affinity and structural compatibility with the JH-binding pocket of JHBP. In contrast, 1-(4-alkylbenzyl) MBIs, which displayed weak or negligible insect growth-regulating activity, exhibited low affinity for JHBP. These findings suggest that the insect growth-regulating activity of MBIs is mediated through inhibition of JHBP function, likely by disrupting the precise regulation of JH concentration in the hemolymph during larval development and pupal metamorphosis. Full article

This work is related to the development of a highly efficient pH-responsive ionic draw solute for forward osmosis applications utilizing microwave-assisted fast heating. This solute is classified as an ionic compound, a sodium salt originating from imidazole, with the scientific acronym 1-acetyl-2-methylbenzimidazole sodium bisulfate (AMBIM-Na). The synthesized compound was analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), as well as additional physical characteristics. The baseline performance was initially evaluated at various molar concentrations against distilled water as the feed solution (FS). The results indicated that the produced solute exhibits elevated osmotic pressure, resulting in a water flux of up to 130 LMH for a 1 M concentration, coupled with the absence of reverse salt flux. The synthesized AMBIM-Na at a concentration of 1 M was utilized as a draw solution (DS) against synthetic brackish water. The water flux declined progressively with the increase in FS concentration, decreasing from 130 LMH with distilled water to 99, 70, and 41 LMH at NaCl concentrations of 5, 10, and 15 g/L, respectively. The regeneration of the draw solute was assessed using pH adjustment, revealing that 100% regeneration occurs by reducing the pH to 2. Full article

In order to design antimicrobial species, a series of methacrylate (Macr) complexes, [Cu(HBzIm)₂(Macr)₂] (1), [Cu₂(HBzIm)₂(Macr)₄] (2), [Cu(2-MeBzIm)₂(Macr)₂] (3), [Cu₂(2-MeBzIm)₂(Macr)₄] (4), and [Cu(5,6-Me₂BzIm)₂(Macr)₂] (5) (HBzIm = benzimidazole, 2-MeBzIm = 2-methylbenzimidazole, and 5,6-Me₂BzIm = 5,6-dimethylbenzimidazole) were synthesized and characterized by several spectral techniques, as well as by single crystal X-ray diffraction. The mononuclear species exhibit a distorted octahedral stereochemistry, while the binuclear types, with a paddle-wheel structure, adopt a square pyramidal surrounding. The methacrylate acts either as a chelate or a bridge, while all benzimidazole derivatives are coordinated as unidentate. The supramolecular networks are developed by both intermolecular π–π stacking interactions and hydrogen bonds. The antimicrobial assays provided both complexes the ability to inhibit planktonic strain proliferation, as well as to adhere on inert substratum. All complexes exhibit a moderate antimicrobial activity, both in regards to standard and clinical isolate strains, the most active being compound 5 against Candida albicans, with a minimum inhibitory concentration (MIC) of 0.156 mg/mL. It is worth mentioning that complex 1 inhibited the microbial adhesion of the clinical Escherichia coli strain and complex 2 constrained that of the clinical C. albicans strain. Full article

A series of hydrazones, azoles, and azines bearing a 4-dimethylaminophenyl-5-oxopyrrolidine scaffold was synthesized. Their cytotoxic effect against human pancreatic carcinoma Panc-1 and triple-negative breast cancer MDA-MB-231 cell lines was established by MTT assay. Pyrrolidinone derivatives 3c and 3d, with incorporated 5-chloro and 5-methylbenzimidazole fragments; hydrazone 5k bearing a 5-nitrothien-2-yl substitution; and hydrazone 5l with a naphth-1-yl fragment in the structure significantly decreased the viability of both cancer cell lines. Compounds 3c and 5k showed the highest selectivity, especially against the MDA-MB-231 cancer cell line. The EC₅₀ values of the most active compound 5k against the MDA-MB231 cell line was 7.3 ± 0.4 μM, which were slightly higher against the Panc-1 cell line (10.2 ± 2.6 μM). Four selected pyrrolidone derivatives showed relatively high activity in a clonogenic assay. Compound 5k was the most active in both cell cultures, and it completely disturbed MDA-MB-231 cell colony growth at 1 and 2 μM and showed a strong effect on Panc-1 cell colony formation, especially at 2 μM. The compounds did not show an inhibitory effect on cell line migration by the ‘wound-healing’ assay. Compound 3d most efficiently inhibited the growth of Panc-1 spheroids and reduced cell viability in MDA-MB-231 spheroids. Considering these different activities in biological assays, the selected pyrrolidinone derivatives could be further tested to better understand the structure–activity relationship and their mechanism of action. Full article

A series of Schiff base derivatives, namely N-(4-methoxyphenyl)-1-(1-methylbenzimidazol-2-yl)methanimine (L¹), 4-methoxy-N-[(1-methylbenzimidazol-2-yl)methyl]aniline (L²), and 2-[(E)-(1-propylbenzimidazol-2-yl)iminomethyl]phenol (L³), were synthesized. These compounds feature different linker groups, including –CH=N–, –CH₂–NH–, and –N=CH–, respectively. During the process of zinc(II) and cadmium(II) complexation in the presence of the closo-dodecaborate [B₁₂H₁₂]^2– anion, it was observed that ligand L³ underwent degradation. Consequently, two compounds were isolated, [Zn(Bz-NH₂)₂(CH₃COO)₂] and (HBz-NH₂)₂[B₁₂H₁₂]∙2CH₃CN, both containing 1-propyl-2-aminobenzimidazole (Bz-NH₂), which is a degraded fragment of the ligand. Several new zinc(II) and cadmium(II) coordination compounds were synthesized and characterized using various physicochemical analysis methods, including elemental analysis, IR, and UV spectroscopy. Additionally, X-ray diffraction and Hirshfeld surface analysis were performed for compounds [Cd(L²)₂(CH₃CN)(H₂O)][B₁₂H₁₂], [Zn(Bz-NH₂)₂(CH₃COO)₂], and (HBz-NH₂)₂[B₁₂H₁₂]∙2CH₃CN, as well as for ligand L². Full article

3-Aroyl and 3-heteroaroyl substituted 3-oxoalkanenitriles were synthesized by the reactions of activated aromatic and hetero-aromatic substances with cyanoacetic acid in the presence of acetic anhydride. As part of studies focusing on the preparation of cyanoacetyl-1-N-methylbenzimidazole, we observed that reaction of N-methyl-benzimidazole with the cyanoanhydride formed by condensation of cyanoacetic acid with acetic anhydride, leads to the formation of 2-(1,3-diacetyl-2,3-dihydro-1H-benzo[d]-imidazol-2-yl)acetonitrile (5), whose structure was confirmed by X-ray crystallographic analysis. 3-Oxoalkanenitriles 3a,b were observed to undergo condensation reactions with dimethylformamide dimethyl acetal (DMFDMA) to afford the corresponding enamino-nitriles, which react with malononitrile to give 2-dialkylaminopyridines through a pathway involving a new, unexpected rearrangement process. Reactions of 3-oxoalkanenitriles with ethyl acetoacetate were found to afford 2-oxopyran-3-carbonitriles, also occurring via this unexpected rearrangement process. Mechanisms to account for both rearrangement reactions are suggested. In addition, reactions of 3-oxoalkanenitriles with acetylacetone in acetic acid in the presence of ammonium acetate result in the formation of pyridine-3-carbonitriles. Finally, upon heating in the presence of zeolite 3-oxoalkanenitriles 3b,c self-trimerized to produce the corresponding aniline derivatives 23b,c. Full article