Search

A synthesis of benzo[d]oxazoles by an N-deprotonation–O-SNAr cyclization sequence from anilide precursors is reported. Anilides derived from 2-fluorobenzaldehydes, activated toward SNAr ring closure by C5 electron-withdrawing groups, were prepared and subjected to deprotonation–cyclization using 2 equiv. of K2CO3 in anhydrous DMF. Following deprotonation at nitrogen, the delocalized anion cyclized from the amide oxygen to give high yields of benzo[d]oxazoles. The temperature required for the cyclization of benzanilides correlated with the potency of the C5 activating group on the SNAr acceptor ring with nitro (most potent) reacting at 90 °C (1 h), cyano reacting at 115 °C (1 h), methoxycarbonyl reacting at 120 °C (2 h), and trifluoromethyl (least potent) reacting at 130 °C (3 h). Acetanilides were more difficult to cyclize but generally required 4–6 h at these same temperatures for completion. Product purification was accomplished by recrystallization or chromatography. [ABSTRACT FROM AUTHOR]

Treating the amide acetanilide (N‐phenylacetamide, C8H9NO) with aqueous strong acids allowed the structures of five hemi‐protonated salt forms of acetanilide to be elucidated. N‐(1‐Hydroxyethylidene)anilinium chloride–N‐phenylacetamide (1/1), [(C8H9NO)2H][Cl], and the bromide, [(C8H9NO)2H][Br], triiodide, [(C8H9NO)2H][I3], tetrafluoroborate, [(C8H9NO)2H][BF4], and diiodobromide hemi(diiodine), [(C8H9NO)2H][I2Br]·0.5I2, analogues all feature centrosymmetric dimeric units linked by O—H...O hydrogen bonds that extend into one‐dimensional hydrogen‐bonded chains through N—H...X interactions, where X is the halide atom of the anion. Protonation occurs at the amide O atom and results in systematic lengthening of the C=O bond and a corresponding shortening of the C—N bond. The size of these geometric changes is similar to those found for hemi‐protonated paracetamol structures, but less than those in fully protonated paracetamol structures. The bond angles of the amide fragments are also found to change on protonation, but these angular changes are also influenced by conformation, namely, whether the amide group is coplanar with the phenyl ring or twisted out of plane. [ABSTRACT FROM AUTHOR]

Heterocyclic chemistry is one of the emerging branches of organic chemistry due to its growing attention in pharmacology. Piperazine is a dinitrogen-containing heterocycle that spans many applications, including anticancer, anticonvulsant, antidepressant, antimicrobial, antimalarial, antiviral, antitubercular, anti-inflammatory, activities etc. In a similar fashion, the second moiety, i.e., acetanilide, an N-phenylacetamide, also executed a large number of bioactivities, which included anticancer, antileishmanial, antipyretic, analgesic, antidiabetic, antiviral potential, etc. Both moieties have large-scale potential to show bioactivities in different aspects. When both moieties combine in a single molecule, it forms a potent biological compound. A number of precursors have been used for the synthesis of piperazine-based acetanilides. In this review, we have addressed different synthetic strategies that have been reported in the past. [ABSTRACT FROM AUTHOR]

The current work explores the antioxidant and antimicrobial activity of a newly synthesized calix[4] arene acetanilide derivative (3), which was synthesized through Mannich reaction by the treatment of calix[4] arene with acetanilide, formaldehyde and acetic acid in tetrahydrofuran, The antioxidant activity was determined by using DPPH method. Results show that the new synthesized compound 3 has good antioxidant activity. The antimicrobial activity of 3 was staunched against different types of microorganisms, i.e. gram-negative and gram-positive bacterial strains (Escherichia Coli ATCC 8739 and Staphylococcus Aureus ATCC 10231) along with a fungus (Aspergillus Niger ATCC 16405). A suitable agar medium (Mueller Hinton agar) was applied for the growth of microorganisms. Kirby-Bauer well agar diffusion method was used to check the antimicrobial activity. The bacterial strains zone has been observed in between 250–4000 µg/ml. It is noticed that compound 3 has very good effect against fungus A niger as compared to bacterial strains. Its minimum inhibitory concentration (MIC) against A. niger, S. aureus and E. coli is found to be 250, 500 and 1000 µg/mL, respectively. Consequently, the study has been compared with the reported calix[4] arene derivatives and it has been revealed that the compound 3 is a good antimicrobial agent. Hence, it could be inferred that compound 3 is considerably effective against selected microorganisms and may be used as a medicine in near future and beneficial for the human. [ABSTRACT FROM AUTHOR]

An efficient and scalable process has been developed for the synthesis of anthranilic diamide insecticide i. e. chlorantraniliprole. The crucial step in this approach is the TiCl4‐mediated aza‐Fries rearrangement of aryl acetanilide to ortho‐aminoaryl ketone. Another key step is the nucleophilic substitution of tosylate into the corresponding bromide using NaBr in the presence of TBAB. All the steps in this synthesis are carried out effectively on a gram scale with excellent yields. [ABSTRACT FROM AUTHOR]

[Display omitted] Recyclization of N -arylitaconimides with hydrazine in dioxane at room temperature selectively leads to 2-(3-oxopyrazolidin- 4-yl)acetanilide derivatives in moderate to good yields. The similar reaction with phenylhydrazine proceeds with the simultaneous formation of isomeric 3- and 5-oxo- 1-phenylpyrazolidine-containing acetanilides. [ABSTRACT FROM AUTHOR]

This paper presents a simple method of obtaining polyamide 6 fibres modified with acetanilide and copper ions. During the spinning of the fibres with the additives applied, a partial reduction of CuSO4 to Cu2+ and Cu+ ions occurs, which is observed as a change in the blue colour of the prepared polyamide granulate to the grey–brown colour of the formed fibres. CuMPs obtained as a result of the salt reduction should give the obtained fibres bioactive properties. Three types of microorganisms were selected to assess the microbiological activity of the obtained fibres, i.e., Gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa and Escherichia coli. The fibres have antibacterial activity against Gram-positive and Gram-negative bacteria. The largest inhibition zones were obtained for the Gram-positive bacteria Staphylococcus aureus, ranging from 1.5 to 4.5 mm, depending on the concentration of CuMPs. The morphology of the fibres' surfaces was examined by means of scanning electron microscopy (SEM) and optical microscopy (OM). The changes in the polymer structure chemistry are studied by Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray structure studies (WAXS and SAXS) and an energy-dispersive spectroscopy (EDS) analysis. The newly obtained bioactive polyamide fibres can be used in many areas, including medicine, clothing and environmental protection for the production of filters. [ABSTRACT FROM AUTHOR]

Due to the high oxidation potentials of electron‐deficient aromatic hydrocarbons, it is difficult to achieve the direct oxidative C(sp2)−H bonds functionalizations of such substrates. Herein, we develop a Ritter‐type amination of electron‐deficient aromatics by merging electricity and sulfate. This practical and straightforward method provides a series of acetanilides from simple electron‐deficient arenes, including mono‐, di‐ and tri‐substituted arenes (22 examples, up to 75 %) with moderate to good yields under mild conditions. This method is characterized by cheap and readily available regents, atom and step economy. [ABSTRACT FROM AUTHOR]

Background: A quick, low cost and precise method was developed and validated for flutamide in the rat plasma using a high-performance liquid chromatography. Acetanilide was used as internal standard in the study. Flutamide was extracted from rat plasma using methanol. The chromatographic analysis was carried out on Cromasil C18 column at 227 nm using methanol–water mixture as the mobile phase and flow rate of 0.8 ml/min. Results: The developed method demonstrated good linearity over the 100–1000 ng/ml concentration range with a regression coefficient of 0.9947. The accuracy of the developed method was found to be 97–101%, while its precision was found to be less than 5%. Limits of detection and quantitation were determined to be 2.52 ng/ml and 7.66 ng/ml, respectively. Flutamide showed recovery of about 96–100% and the developed method was further used to investigate the pharmacokinetics of flutamide in the marketed formulation. Conclusions: From the results, it can be concluded that the developed method has the potential to successfully determine flutamide in rat plasma and establish the pharmacokinetic parameters of other flutamide-containing formulations. [ABSTRACT FROM AUTHOR]

Small molecule inhibitors of the focal adhesion kinase are regarded as promising tools in our armamentarium for treating cancer. Here, we identified four 1,2,4-triazole derivatives that inhibit FAK kinase significantly and evaluated their therapeutic potential. Most tested compounds revealed potent antiproliferative activity in HepG2 and Hep3B liver cancer cells, in which 3c and 3d were the most potent (IC50 range; 2.88 ~ 4.83 µM). Compound 3d possessed significant FAK inhibitory activity with IC50 value of 18.10 nM better than the reference GSK-2256098 (IC50 = 22.14 nM). The preliminary mechanism investigation by Western blot analysis showed that both 3c and 3d repressed FAK phosphorylation comparable to GSK-2256098 in HepG2 cells. As a result of FAK inhibition, 3c and 3d inhibited the pro-survival pathways by decreasing the phosphorylation levels of PI3K, Akt, JNK, and STAT3 proteins. This effect led to apoptosis induction and cell cycle arrest. Taken together, these results indicate that 3d could serve as a potent preclinical candidate for the treatment of cancers.

In this study, the preparation method of acetanilide, which is commonly taught in current undergraduate experimental courses, is improved. While acetic acid and aniline were used as starting materials in the improved method, zinc powder was replaced with stannous chloride (which is listed as an easy-to-make tube explosion product) as a reducing agent to prevent aniline from being oxidized. At the same time, p-toluene sulfonic acid was added as a catalyst. A fixed bed dehydration reflux device was used instead of the classical fractionation device, and a packed rectification column was used as the fixed bed. The column was filled with glass spring packing, a 4A molecular sieve and color-changing silica gel from bottom to top in turn. During the reaction, distilled water and acetic acid were fractionated by the glass spring packing, acetic acid was refluxed to the reaction flask, and water was absorbed by the 4A molecular sieve and color-changing silica gel. After absorbing water, the color of the silica gel changed from orange to green, which is a clear indication of the reaction process. The improved experiment does not require control reagents, the reaction time is shortened, and the phenomenon is rich, making it more suitable for undergraduate teaching. In addition, two extended experiments were designed in this study, which can be selected according to the needs of teaching. One is to prepare phenyl 4-acetylaminoacetate from acetanilide; the second is to determine the unreacted aniline content in the waste liquid by constant pH titration. This modified experimental procedure employs extraction, column chromatography, titration, and data processing and analysis, which can effectively improve the comprehensive experimental ability of the students. [ABSTRACT FROM AUTHOR]

In this study, we have investigated ciprofloxacin-based acetanilides for their in-vitro inhibitory study against gram +ve, -ve bacteria and serine protease activity. The compounds 4e and 4g showed excellent antibacterial activity against Bacillus subtilis with a zone of inhibition (ZI) values of 40 ± 0.9 mm, 37 ± 1.4 mm and with MIC values of 4.0 ± 0.78 mg/mL, 3.0 ± 0.98 mg/ML respectively, while 4a and 4i were found most active against Escherichia coli, with ZI values 38 ± 0.1 mm, 46 ± 1.8 mm and with MIC values of 1.0 ± 0.25 mg/mL, 1.0 ± 0.23 mg/mL respectively. All derivatives (4a-j) significantly inhibited the catalytic activity of serine protease, while 4a exhibited a maximum (100%) inhibitory effect at 96 minutes having 22.50 minutes t12 , and non-competitive inhibition with 0.1±0.00μM Ki. The IFD/MM-GBSA studies highlighted the binding mode of 4a for protease inhibition and indicated improved binding affinity with –107.62 kcal/mol of ΔGbind. [ABSTRACT FROM AUTHOR]

In this study, a simple, accurate, precise, and cost-effective method based on reversed-phase high-performance liquid chromatography with diode array detection for the quantification of aceclofenac in a small volume of human serum (100 µL) was developed and validated according to US-FDA guidelines. Acetanilide was used as an internal standard. The analyte and internal standard were spiked in human serum and extracted using a simple protein precipitation technique. The analysis was carried out on a reversed-phase C18 HPLC column (5 μm, 4.6 × 250 mm) using 0.1% formic acid and acetonitrile in a ratio of 40 : 60 (v/v) as the mobile phase with UV detection at 275 nm at a flow rate of 1.2 mL/min. The developed method was found to be sensitive, selective, and linear over the concentration range of 0.8–20 µg/mL with good precision (RSD ≤ 15%) and accuracy (relative error ≤15%). The limit of detection and lower limit of quantification were found to be 0.3 and 0.8 µg/mL, respectively. [ABSTRACT FROM AUTHOR]

Reported herein is a reactivity of propargyl alcohols as "Three‐Carbon Synthons" in a Rh(III)‐catalyzed C−H functionalization of acetanilides, leading to the synthesis of core structures of isocryptolepine, γ‐carbolines, dihydrochromeno[2,3‐b]indoles, and diindolylmethanes (DIM) derivatives. The transformation involves a rhodium(III)‐catalyzed C−H functionalization and heteroannulation to yield indoles followed by a cascade cyclization with both external and internal nucleophiles to afford diverse products. The role of the hydroxy group, the key function of the silver additive, the origin of the reverse regioselectivity and the rate‐determining step, are rationalized in conformity with the combination of experimental, noncovalent interaction analysis and DFT studies. This protocol is endowed with several salient features, including one‐pot multistep cascade approach, exclusive regioselectivity, good functional group tolerance and synthesis of variety of molecular frameworks. [ABSTRACT FROM AUTHOR]

The regioselectivity of two mechanistically distinct alkenylation reactions catalyzed by in situ‐formed cationic transition metal complexes was studied using N‐allyl‐N‐phenylethenesulfonamide as a model compound. Orthogonal selectivity was observed for the Ru‐catalyzed C−H‐activating alkenylation with acetanilides, which occurs preferentially at the electron deficient double bond, and for a Pd‐catalyzed Heck‐type coupling with arene diazonium salts, which occurs preferentially at the more electron rich double bond of the N‐allyl substituent. [ABSTRACT FROM AUTHOR]

The rapid expansion of the dye industry has led to severe environmental pollution. The lack of real-time direct determination methods for dye intermediates is a key factor in high pollution emissions and low product quality in the continuous synthesis of dyes. This study proposes an accessible, fast, and precise approach for the clean and direct determination of 3-(N,N-Diethylamino)acetanilide (DEAA), a dye intermediate used in the synthesis of the azo dye Disperse Violet 93:1. For precise DEAA quantification, we developed a multi-pathlength and multi-wavelength coupled differential photometric approach based on the absorption spectra characteristics of DEAA at various concentrations and optical pathlengths. A relatively stable analytical sensitivity (0.5671–66.2630) and a large concentration range of 0.01–11% were obtained. Compared to the traditional single-optical pathlength and single-wavelength quantification, this new method possessed 119 times higher sensitivity. The maximum quantitative relative error decreased from 9.17% to 2.44%. The orbital contribution and distinctive peak electronic excitation mechanism of DEAA were uncovered using TD-DFT. By comparing the oscillator strength and peak position variations between the target DEAA and coexisting sulfuric acid, the unique spectral behavior of DEAA, such as its high sensitivity and selectivity, was explained. In addition to providing a reference for real-time industrial dye and intermediate monitoring, this study lays the methodological groundwork for future research. In light of the new method's short time consumption and non-secondary pollution benefits, we further believe it will be crucial in controlling the industrial synthesis process in order to improve product quality, resource conversion efficiency, and effectively prevent excessive pollution generation. [Display omitted] • A novel method for selecting multiple pathlengths and wavelengths is proposed. • The method achieves high sensitivity and large-range quantification. • The segmented differential method reduces quantitative relative error by 73.39%. • DFT reveals the electronic excitation mechanism in the DEAA absorption spectra. [ABSTRACT FROM AUTHOR]

New thiazole and thiadiazole derivatives bound to the acetanilide moiety were synthesized and evaluated for their cytotoxic activity. The precursor N-(4-acetamidophenyl)-N'-phenylthiourea (2) was cyclocondensed with ethyl bromoacetate to afford a mixture of the two isomers, 2-(4-acetamidophenylimino)-3-phenylthiazolidin-4-one (3a, 23%) and 3-(4-acetamidophenyl)-2-phenyliminothiazolidin-4-one (3b, 71%). The Knoevenagel reaction of 3b with various aromatic aldehydes afforded 5-arylidene-2-phenyliminothiazolidin-4-one derivatives 5a–5e. Intramolecular cyclization of thiourea scaffold 2 with chloroacetone and/or phenacyl chloride gave the conforming thiazole derivatives 6a and 6b. A new series of thiadiazole derivatives 9a–9c and 11a–11c was synthesized by the reaction of N-(4-acetamidophenyl)-N'-phenylthiourea (2) with selected derivatives of hydrazonoyl halide in ethanol and triethylamine. The structures of the synthesized thiazole and thiadiazole compounds were elucidated by their compatible spectral data. The cytotoxic activity of the synthesized thiazole and thiadiazole derivatives was screened against four human cancer cell lines and showed promising results. Thiazolidin-4-one compound 5d showed the strongest cytotoxic effects on hepatocellular carcinoma (IC50 = 8.80 ± 0.31 μg/mL), mammary gland breast cancer (IC50 = 7.22 ± 0.65 μg/mL) and colorectal carcinoma (IC50 = 9.35 ± 0.61 μg/mL) cell lines. [ABSTRACT FROM AUTHOR]

In the present work, newly designed ethyl 2-oxo-2H-selenopyrano[2, 3-b]quinoline-3-carboxylates (4a–4f) were synthesized by reaction of 3-formyl-2-selenoquinolines (3a–3f) with diethyl malonate in the presence of catalytic amounts of piperidine. The intermediate 3-formyl-2-selenoquinolines (3a–3f) were synthesized by the action of NaHSe on substituted 2-chloroquinoline-3-carbaldehydes (2a–2f). The new series of 2-chloroquinoline-3-carbaldehydes (2a–2f) were synthesized from the corresponding substituted acetanilides (1a–1f) using available literature methods. The structures of all synthesized compounds were characterized by elemental analysis, IR, 1H NMR, and mass spectroscopy data. Newly synthesized compounds were evaluated for their antibacterial properties and found to exhibit a wide spectrum of antibacterial activity. In particular, compounds 4d and 4e were highly active against S. aureus and M. roseus species. [ABSTRACT FROM AUTHOR]

This study evaluated the impact of differential sowing windows and improved weed management strategies on weed dynamics, productivity, and economic viability of direct drum seeded rice (Oryza sativa L.) in the temperate agro-ecosystem of Kashmir. A two-year field experiment was conducted utilizing a split-plot design with two sowing dates (May 10 and June 3) as main plots and six weed management practices as sub-plots. The earlier sowing date (May 10) resulted in significantly enhanced leaf area index, crop growth rate, relative growth rate, net assimilation rate, and grain and straw yields compared to the later sowing (June 3). Among weed management treatments, four mechanized conoweedings (equivalent to weed-free conditions) and sequential application of bensulfuron methyl + pretilachlor (60 and 600 g a.i. ha -1 ) as pre-emergence followed by 2,4-D (0.75 kg a.i. ha -1 ) as post-emergence demonstrated superior efficacy in weed suppression and augmentation of crop growth parameters and yield attributes. These treatments also exhibited the lowest weed index and highest benefit-cost ratio. The May 10 sowing, coupled with efficacious weed control measures, significantly reduced weed density and biomass while concomitantly improving nutrient uptake and economic returns. The results indicate that adopting a May 10 sowing date for direct seeded rice, in conjunction with either four conoweedings or the aforementioned sequential herbicide application, can optimize agronomic productivity and economic profitability under the temperate conditions of Kashmir. The study aided in choosing the best sowing window and efficient weed management strategy for attaining higher productivity and profitability of direct seeded rice in temperate conditions., (© 2024. The Author(s).)

Epidermal Growth Factor Receptor (EGFR), its wild type and mutations L858R/T790M, is overexpressed in non-small cell lung cancer (NSCLC) patients and is considered an inevitable oncology target. However, while the potential EGFR inhibitors have been represented in the literature, their cellular activity failed to establish broad potency against EGFR and its mutations. This study identifies a new series of EGFRL858R/T790M inhibitors bearing hydantoin acetanilides. Most compounds revealed strong antiproliferative activity in a range of NSCL cancer models (A549, H1975, and PC9), in which 5a and 5f were the most potent. Compounds 5a and 5f possessed potent anticancer activity on H1975 cells with IC50 values of 1.94 and 1.38 µM, respectively, compared to 9.70 µM for erlotinib. Favorably, 5a and 5f showed low activity on WI-38 normal cells. Western blotting and an EGFR kinase assay test proved the significant EGFR inhibitory activity of 5a. Besides, active hydantoin derivative 5a strongly arrested the cell cycle at the sub G1 and S phases and triggered apoptosis in A549 cells. These results imply that 5a could be considered a promising lead compound for additional development as a potential active agent for anticancer therapy. [ABSTRACT FROM AUTHOR]

An efficient method for direct thiolation of anilides with thiols using NiCl2 ·6H2 O as the catalyst is developed. Using this method, the desired products were successfully synthesized in moderate to good yields. Initial mechanistic studies suggest that this reaction proceeds through a radical pathway. [ABSTRACT FROM AUTHOR]

Alkoxy group substituted compounds of acetanilide are found to have pharmacological and industrial importance. Synthesis of alkoxy substituted acetanilides via conventional thermal methods involves multi-step processes, formation of side products, and the poor yield of desired products. But, the vast literature studies reveal that electroorganic synthesis of alkoxy substituted acetanilide derivatives would be effectively carried out through electrochemical oxidation methods. The direct substitution of the ethoxy (alkoxy) group onto the aromatic ring, an electrophilic substitution, has not been attempted so far. This concept is taken as a preparatory attempt to find an alternative method to the tedious chemical route and to invent a direct method of introducing the ethoxy groups into the aromatic ring in a single step. A polarization study on acetanilide with ethanol as an electrolyte is carried out on platinum and graphite anodes to find out the oxidation potentials. Electrochemical ethoxylation of acetanilide at the platinum electrode is done by the Potentiostatic method using the oxidation potentials. The products are separated using preparative TLC and purified with suitable solvents. The products are characterized by UV, IR, NMR, and Mass spectra. [ABSTRACT FROM AUTHOR]