Large accumulations of copper (Cu) ions in the human body may cause damage, including organ and brain damage. In recent years, studies have proven that a large accumulation of Cu ions can lead to Parkinson’s disease and Alzheimer’s disease; therefore, it is great important to develop novel strategies for detecting trace Cu in environmental and biological samples. In this work, we designed two new coumarin-based colorimetric and fluorescent probes, HQ1 and HQ2. These two probes could selectively respond to Cu 2+ with obvious color and fluorescence changes, and the presence of other metal ions had no effect on these changes. The two probes also exhibited high sensitivity for Cu 2+ , with a detection limit as low as 1.81 × 10 –8 M/1.57 × 10 –8 M. Notably, the two probes showed potential practical applications and were successfully used for detecting Cu 2+ in a test strip, A549 cells, and living zebrafish larvae.
The tannic acid–based iron nanoparticle (TAN-Fe-NP) was prepared by a redox reaction between tannic acid and FeCl 3 in water and characterized by the Fourier transform infrared spectroscopy, ultraviolet–visible spectroscopy, energy dispersive X-ray analysis, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy techniques. Then, a TAN-Fe-NP nanocatalyst was used as an efficient catalyst for the synthesis of polyhydroquinolines from the reaction of ethyl acetoacetate, benzaldehydes, dimedone, and ammonium acetate in ethanol at 60 °C in high yields and low reaction times. Since this catalyst is made of natural materials, it has a great advantage compared with the other catalysts and is cheap, available, natural, safe, nontoxic, and eco-friendly as well.
Molecules that target quorum sensing and biofilm inhibition are useful antimicrobials. In this regard, a new diarylhydrazone was synthesized and characterized using infrared, high-resolution mass spectrometry and nuclear magnetic resonance experiments as N-[( E)-4-bromo-2,5-diheptyloxybenzylideneamino]-2,4-dinitroaniline (BHBANA). Minimal inhibitory concentrations (MICs) vary from 0.625 to 2.5 mg mL−1. This compound was screened in vitro for its inhibition of quorum sensing–mediated violacein production by Chromobacterium violaceum CV12472 at MIC and sub-MIC and showed percentage inhibition varying from 100% at MIC to 5.7% ± 0.2% at MIC/32. Against Chromobacterium violaceum CV026, BHBANA exhibited anti-quorum-sensing zone diameters of 10.5 ± 0.3 mm and 7.0 ± 0.1 mm at MIC and MIC/2, respectively. BHBANA shows concentration-dependent inhibition of swarming motility on flagellated Pseudomonas aeruginosa PA01 with the highest % inhibition of 28.30% ± 0.50% μg mL−1 at MIC. The product inhibits biofilm formation, with the best biofilm inhibition being observed against Staphylococcus aureus varying from 72.24% ± 0.86% (MIC) to 09.82% ± 0.10% (MIC/8). Molecular docking studies carried out utilizing the Schrodinger software identified interactions between BHBANA and different receptor compartments of Chromobacterium violaceum, which can block pathogenic gene expression. The results suggest the potential of BHBANA in reducing microbial virulence.
Two 19th-century historical violet dyes from the Historische Farbstoffsammlung, Technical University of Dresden, have been analysed by liquid chromatography–mass spectrometry (LC-MS). The data are presented as charts with retention time and two scales: electron spray mass spectrometry counts ( m/z) and milli-absorption units (UV). These dyes are complex mixtures as anticipated from the synthetic methods involving partial alkylation of rosaniline or synthesis using mixtures of N-methylaniline and N,N-dimethylaniline. The charts typically show chromophores separated by CH 2 units which have separated well. Hofmann’s violet is presumably made by Hofmann’s method of synthesis, but the analyses do not verify with certainty who the inventors are because of the complexity of the dye mixtures.
A new continuous flow synthetic method for preparing indole and its derivatives are successfully developed to overcome the disadvantages of traditional batch methods, such as low conversion rates, long reaction times, and amplification effects. The method represents a sustainable and efficient preparation of indole and its derivatives without the need for additional catalysts. By investigating the effects of the reaction temperature, the solvent, the equivalence ratio, and the residence time, high conversion rates and excellent yields were simultaneously achieved within 20 min under optimized conditions. For the template reaction, DMSO/H2O/AcOH = 2:1:1 is used as the solvent, the reaction temperature is 110 °C, and the ratio of phenylhydrazine hydrochloride to cyclopentanone is 1:1.05. Indole and a wide array of its derivatives are synthesized to verify the universality of the method, and most of the reactions exhibit satisfactory conversion rates and high yields are obtained. This new continuous flow method is more suitable for industrial scale-up relative to traditional batch methods.
Four lignans, asarinin (1), horsfieldin (2), 5-(4-(3,4,5-trimethoxyphenyl)hexahydrofuro[3,4-c]furan-1-yl)benzo[d][1,3]dioxole (3), 5-(4-(3,5-dimethoxyphenyl)hexahydrofuro[3,4-c]furan-1-yl)benzo[d][1,3]dioxole (4), and four non-alkaloid compounds, piperonylic acid (5), hesperidin (6), syringin (7), and beta-sitosterol (8) were isolated from the stem bark of Zanthoxylum rhetsa grown in Vietnam. Their chemical structures were elucidated by spectroscopic analysis and compared with the references. Except for compound 6, all the remaining compounds (1-5, 7, and 8) were isolated for the first time from Z. rhetsa. The isolated compounds were tested for their cytotoxic activity against three human cancer cell lines, LU-1, Hep-G2, and KB. Compound 5 showed moderate cytotoxic activity against all three cell lines with IC50 values ranging from 48.13 to 49.06 mu g mL-1. Notably, compound 6 demonstrated selective cytotoxicity against LU-1, Hep-G2, and KB cancer cell lines (IC50 66.48-67.41 mu g mL-1) while non-toxic toward normal Vero cell. Compound 6 also exhibited its ability to inhibit main protease (Mpro) enzyme in vitro with an IC50 value of 55.49 mu g mL-1 and in silico with the binding affinity toward targeted protein of -14.36 kcal mol-1.
Optimized reaction conditions are developed to obtain a series of [(7-chloroquinolin-4-yl)sulfanyl] alcohol derivatives as intermediates to prepare a range of (7-chloroquinolin-4-ylthio) alkylbenzoate derivatives. The structures of all the synthesized compounds are confirmed from their infrared and nuclear magnetic resonance spectral data, and by elemental analysis. In silico ADME/Tox profiling studies of the synthesized molecules are undertaken, and the potential antimalarial activity of the products is determined. In vitro, all the prepared compounds significantly reduce heme crystallization with IC 50 values of < 10 µM. In vivo, the reduction in parasitemia levels and survival time increases are marginal.
Activated carbon is produced from Burmese grapes using NaOH as the activator under microwave irradiation. Through scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction analysis, and Brunauer–Emmett–Teller analysis methods, the activated carbon material is found to have a rough and uneven surface with the formation of pores, an amorphous structure, and possesses hydroxy, C–H, carbonyl, alkene, and ether functional groups. The surface area (478.5 m 2 g −1 ) and pore size (about 3.4 nm) are calculated from the adsorption N 2 equation. The adsorption mechanism of activated carbon is evaluated and follows a pseudo-first-order kinetic model (large single adsorption) and the Langmuir isotherm model (physical interaction). The factors affecting ciprofloxacin adsorption using activated carbon derived from Burmese grapes are also evaluated and optimized by the response surface method model based on influencing factors including the contact time, the solution pH, the antibiotic concentration, and the material dosage. The optimal parameters are as follows: pH = 6.26, concentration = 58.9 mg L −1 , content = 0.15 g L −1 , time = 54 min. Under optimal conditions, the adsorption capacity predicted from the model is 191.33 mg g −1 with an efficiency of 41.35%.
Vismodegib is the first hedgehog signaling pathway inhibitor approved by the Food and Drug Administration (FDA) for the treatment of basal-cell carcinoma. The reported methods for the preparation of vismodegib mostly require the employment of precious metal catalysts and phosphine ligands. An alternative low-cost method avoiding the employment of precious metal catalysts and phosphine ligand is developed to prepare vismodegib in a laboratory. The reported method is applied in an undergraduate experimental course to verify its reproducibility and to develop the experimental skills of students. Moreover, the teaching practice experiences are summed up to provide suggestions for the development of exploratory and further experimental courses.
p-Phenylenediamine reacts with Sanger's reagent in hot ethanol to give the expected mono- and di-substitution products, but in ethanol at room temperature, it gave exclusively 2-nitro-5-fluorophenyl-p-phenylenediamine, where a hydrogen atom is displaced by attack at an activated, unsubstituted position. The reactions of p-phenylenediamine and aniline with Sanger's reagent were compared in the cheap, 'green' solvent ethanol.
[2.2]-Paracyclophane derivatives have been promising platforms for applications in biology and materials science. To access pure derivatives thereof, a safe and non-toxic synthetic method for 4-n-propyl-[2.2]-paracyclophane is developed via a microwave-assisted and NH2NH2/KOH reduction route. We introduce microwave-assisted acylation for a synthesis that successfully improves the yield and reduces the reaction time. Notably, an exploration of the length and number of the alkyl chains on the [2.2]-paracyclophane ring did not significantly affect the outcome of this reaction. We synthesized 4-n-butyl-[2.2]-paracyclophane and 4,12-dipropyl-[2.2]-paracyclophane via our protocol with high yields. The regioselectivity of the second electrophilic substitution on 4-n-propyl-[2.2]-paracyclophane occurs at the para position of the less substituted phenyl ring.
Alkyl-substituted testosterone derivatives are promising platforms for new drug discovery in medicinal chemistry. This approach provides a simple and efficient method for introducing an alkyl substituent to steroids at the C-4 position. In this study, the novel compound 3α-hydroxy-3β-methyl-4,4-dimethyl-5α-21-bromo-19-nor-pregnan-20-one is synthesized from 19-nor-testosterone. The protocol involves methylation of the dienolate, reduction of the alkene, the Grignard reaction of the carbonyl group, a Wittig reaction, hydroboration with BH 3 , the oxidation and bromination with a 49% overall yield. For the methylation and reduction steps, the effects of the base, solvent, and reactant ratio on the conversion and yield are investigated. The structures of the synthesized compounds are determined by nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS) (electrospray ionization (ESI)).
A new zinc(II) metal organic framework has been obtained from the solvothermal assembly of 1,3,5-benzene tricarboxylate and 1,3-bis(imidazole)propane with zinc nitrate in DMAc–H 2 O (DMAc is N,N-dimethylacetamide), namely {[Zn 2 (μ 2 -OH)(1,3-BIP)(BTC)]·DMAc·2H 2 O} n (SNUT-6). The product is characterized by single-crystal and powder X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, and elemental analysis. The single-crystal X-ray diffraction reveals that SNUT-6 exhibits a 3D→3D two-fold interpenetrating framework. Furthermore, SNUT-6 demonstrates a highly efficient turn-off fluorescent detection ability for aniline in methanol and shows high sensitivity with a K sv value of 4.771 × 10 4 M −1 . It also shows excellent photocatalytic degradation performance for a three-dye molecular model: rhodamine b, methyl orange, and methyl blue.
Phorbol esters and their derivatives, such as TPA, have been reported as potential natural antitumor products, with some derivatives entering clinical research for leukemia treatment. In this study, 16 phorbol derivatives were synthesized from phorbol, and their anti-leukemia activity against Jurkat, HL-60, and K562 were tested. The results showed that several derivatives had anti-leukemia activity, with 5B demonstrating the strongest cytotoxic activity against the K562 cell line (IC 50 = 0.24 ± 0.04 μM). Based on the IC 50 values, a structure-activity relationship was established. When the substituent contained an aromatic group, phorbol derivatives esterified with long-chain organic acids at three reactive hydroxyl groups (C12-OH, C13-OH, and C20-OH) had better activity. When aryl groups were absent from the substituent groups, phorbol derivatives esterified with short-chain organic acids at two hydroxyl groups had better activity. Derivatives esterified with heterocyclic acids, either tri-substituted or di-substituted, showed a significant decrease in cytotoxicity. The mechanism of anti-leukemia activity was explored through flow cytometry, which indicated that phorbol esters inhibited the growth of leukemia cells by inducing apoptosis, leading to cell death. Molecular docking data of compound 5B docking to PKC δC1B suggested that substituent groups should not be too large, and caution should be taken when substituting C20-OH. Overall, these findings provide valuable insights into the design of more effective phorbol esters as anti-leukemia agents, but further research is needed to confirm their safety and efficacy in clinical settings.
Lithium-ion batteries have transformed our lives and are now found in everything from mobile phones to laptop computers and electric cars. In lithium-ion batteries, an adequate electrolyte was developed using a winding process nearly related to the progress of electrode chemistries. In this technology, a metal oxide is a cathode, and porous carbon is the anode. The electrochemical interaction of anode material with lithium could produce an intercalation product, which could form the basis of a revolutionary battery system. Structural retention causes this reaction to proceed quickly and with a high degree of reversibility at room temperature. Titanium disulfide is one of the latest solid cathode materials. In this review, the history of intercalation electrodes, electrolytes, and basic principles related to batteries based on intercalation processes and their effect on battery performance is reported.
PDE4 inhibitors exhibit anti-stress and antidepressant-like abilities by catalyzing the hydrolysis of cAMP, a primary regulator for intracellular communication in the brain. Herein, novel diarylpyrazole derivatives are synthesized and investigated for their ability to inhibit PDE4. In vitro studies indicate that most of the synthesized compounds show significant potency for the inhibition of PDE4. Specifically, N-(4-(3-(3,5-dimethoxyphenyl)-1 H-pyrazol-5-yl)benzyl)-2-morpholinoethan-1-amine exhibits the most potent PDE4 inhibition, with an IC 50 value of ca. 0.09 μM. It also produces antidepressant-like activities in sugar water consumption and in forced swimming tests in vivo.
In this study, a series of 4-(3-benzylbenzo[d]thiazol-2(3H)-ylidene)-cyclohexa-2,5-dien-1-one derivatives are efficiently synthesized in excellent yields by reactions of 2-chlorobenzothiazole, benzyl bromides, and phenols in acetonitrile under reflux and catalyst-free conditions in the presence of triethylamine for 2 h. The structures of the products are characterized by NMR, IR, EI-MS, and elemental analyses.
This study aims to investigate the adsorption characteristics of tetracycline from polluted waters using C-4hydroxyphenylcalix[4]resorcinarene as an adsorbent. The adsorptive efficiency of C-4-hydroxyphenylcalix[4]resorcinarene is optimized by adjusting various operational parameters such as the adsorbent dosage, the pH, the contact time, the temperature, and the initial adsorbate concentration. The most efficient remediation is 96% at 10.0 mg/L tetracycline as the initial concentration, 0.05 mg/L C-4-hydroxyphenylcalix[4]resorcinarene, a contact time of 30 min, pH 5.6, and ambient temperature. The adsorption ability of C-4-hydroxyphenylcalix[4]resorcinarene toward tetracycline is also investigated in water with different characteristics, including solutions with and without the addition of background salts. The results show that C-4-hydroxyphenylcalix[4]resorcinarene can effectively remove tetracycline from aqueous solutions with an adsorption capacity of ca. 36.9 mg/g. The study also finds that the removal process followed pseudo-second order kinetics and Freundlich isotherm models. Moreover, the adsorption is spontaneous and exothermic, suggesting a thermodynamically favorable chemisorption process. In addition, the optimized method is successfully applied to remove tetracycline from various real natural water systems.
The solubility data of sodium theophylline salt in the water and aqueous sodium hydroxide systems with molarities of 0.00, 0.01, 0.10, 0.20, 0.49, and 0.96 mol kg −1 at temperatures ranging from 283.15 to 368.15 K are determined via the equilibrium method. The experimental results show that the solubility of sodium theophylline increases on increasing the temperature at the same concentration of NaOH solution and decreases with an increase in the NaOH concentration at the same temperature. These results correlate well with the polynomial empirical equation, the modified Apelblat equation, and the λh equation. At the same time, it is found that the modified Apelblat equation gives better correlation results than the polynomial empirical and the λh equations. The results show that the three models correlate well with the solubility data of sodium theophylline. The modified Van’t Hoff equation is used to estimate the thermodynamic properties including the dissolution enthalpy, the dissolution entropy, and the Gibbs free energy change of sodium theophylline when dissolved in aqueous NaOH solution at different concentrations. The solubility data and correlation results obtained from the experiments can provide basic data for the cooling crystallization, separation, and purification of sodium theophylline and are expected to be of great significance for the research and development of sodium theophylline and for caffeine production.
In this study, we used a synthetic aerogel based on PVA/agar/maltodextrin to remove the antibiotic ciprofloxacin (CFX) from aqueous media. Response surface method (RSM) is used to study the relationship between the factors affecting the adsorption process, thereby optimizing the adsorption efficiency, and making decisions on improving the adsorption process better sub. The research results obtained are as follows: pH2, initial CFX concentration 51 mg L −1 , adsorbent dosage 0.16 g L −1 , adsorption time 120 min, and temperature 51.5 °C reached the maximum adsorption capacity. The maximum additive is 38.63 mg g −1 . The experimental data agree with the pseudo-quadratic kinetic model and the Langmuir and Temkin isotherm models. The composite aerogel adsorbent (AE) in this study is a potential candidate for adsorbent to remove antibiotic contamination in aqueous media.
