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p-Fluorophenacyl chloride (1) was used as a building block for the preparation of new tetra-substituted thiophene derivatives. The basic-catalyzed reaction of 1 with various thiocarbamoyl compounds such as 2-acetyl-2-substituted-thioacetanilides 2a,b, 3-arylazo-4-mercapto-4-phenylamino-buten-2-ones 5a–c, ethyl 2-arylazo-3-mercapto-3-phenylamino-acrylates 8a–c, N-aryl-2-cyano-3-mercapto-3-phenylamino-acrylamides 11a–c, N-aryl-2-(mercapto(phenylamino)methylene)-3-oxo-butanamides 14a–c, and 2-mercapto-4,6-dimethylnicotinonitrile 17 led to the production of their corresponding substituted thiophene compounds 4a–b, 7a–c, 10a–c, 13a–c, 16a–c, and 19 in moderate yields. The newly synthesized thiophene compounds were deduced according to FTIR, 1H NMR, 13C NMR, 19F NMR, and mass analyses along with micro-analytical data. The synthesized thiophene compounds were tested to evaluate their antibacterial and antioxidant activities. The majority of the synthesized thiophenes showed good to moderate anti-bacterial and antioxidant activities. The hydroxythiophene compound 4a showed extremely high antibacterial activity with inhibition zones 15–21 mm (from 60 to 87.5% activity indices). It inhibits bacterial growth and approaches the activity of Ampicillin, which inhibits bacteria with areas of inhibition from 23 to 25 mm. The hydroxythiophene compound 4a showed excellent antioxidant properties (85.9%) relative to the reference, Ascorbic acid (88.0%). [ABSTRACT FROM AUTHOR]

The new cyclohexenone derivatives have been synthesized by diazo-coupling reactions using 3,5-diphenylcyclohex-2-en-1-one (2) and hydrazone derivative 3 as versatile scaffolds. The structures of the newly synthesized compounds were smoothly elucidated based upon different spectral techniques. The new compounds which bearing azo, triazene or tetraazene moieties were evaluated as antioxidant and antimicrobial agents. The minimal inhibitory concentrations (MICs) values for the most active compounds in antibacterial activity were evaluated. Compounds 8 and 15 revealed the highest antioxidant activity with inhibition values (53.5%) and (47.8%), respectively. In the case of S. aureus, compound 10 exhibited potent antibacterial activity with (95.8%) AI. In the case of E. coli, compound 10 revealed excellent antibacterial activity with (84.6%) AI. In the case of C. albicans, compounds 10, 12 and 14 revealed the best activities with an activity index (66.7–74.1%). [ABSTRACT FROM AUTHOR]

A series of 6-acetyl-2,4-diaryl-2,3,4,5-tetrahydro-1,2,4-triazines (2a–2f) was synthesized by double Mannich reaction of the hydrazone 1a or 1b with formaldehyde and the appropriate amine. A similar reaction of 1a with the appropriate diamine afforded the bis(tetrahydro-triazines) 3a–b, and 4a–b. Whereas, the 6-cinnamoyl derivatives 5a-c were obtained by the reaction of 2a with the appropriate aldehyde. The hydrazone 7, derived from 2a, was treated with the appropriate aldehyde or ketone to afford the mixed azines 8–12 and 13–16. The biological activity, antibacterial, antifungal and antioxidants of the most newly synthesized compounds of these derivatives were screened. Compounds 2b, 3a and 7 revealed the best results against all screened biological activity [ABSTRACT FROM AUTHOR]

3,5‐Diphenylcyclohex‐2‐en‐1‐one (1) was used as a starting material for the synthesis of new derivatives of hydrazones 3, 4, organic compounds that involves thiazole ring 5–8 and azine moieties 10–17. The biological activity, minimum inhibitory concentration (MIC) and cytotoxicity values of the most active compounds of these derivatives were screened. Compounds 7 a, 7 b and 8 b revealed the best results against all screened biological activity. Derivatives 7 a, 7 b and 8 b revealed moderate to weak cytotoxicity. [ABSTRACT FROM AUTHOR]

4-Formylphenyl benzoate was utilized as a versatile precursor for the construction of new series of heterocyclic scaffolds that contain thiazole and thiazolidin-5-one rings. The antibacterial activity of these scaffolds against two types of bacteria was screened and most of them exhibited good activity. Among the synthesized thiazole derivatives, compounds 5, 6, and 8a showed antibacterial activity close to the standard chemotherapeutic (Ampicillin). [ABSTRACT FROM AUTHOR]

Oxazolone derivative 3a was utilized as a versatile precursor for the construction of new heterocyclic scaffolds containing imidazole, oxazine, triazine, and triazole rings (compounds 20, 21, 23, and 24, respectively). Furthermore, 4‐aminohippuric acid (2b) was used in the synthesis of various new oxazolone derivatives (13–19) by utilizing of its amino group in several transformations followed by heterocyclization of these compounds with aldehyde 1 via classical Erlenmeyer condensation method to give the targeted oxazolones. On evaluation of these compounds as antioxidant and antibacterial agents, compounds 20 and 24 exhibited a good antioxidant activity, while compounds 20, 23, and 24 exhibited a good antibacterial activity against Escherichia coli and Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

This review highlights the methods used for the synthesis of 3-oxo-N-(pyridin-2-yl)butanamide compounds. The reactivity and synthetic importance are investigated. In this context, recent progress in the synthesis and use of 3-oxo-N-(pyridin-2-yl)butanamide as precursors for heterocyclic compounds is reviewed. The synthetic routes for preparation of 3-oxo-N-(pyridin-2-yl)butanamide are based on the reaction of diketene with aromatic primary amine and reaction of 2-aminopyridine withβ-keto-t-butylthioester or ethylacetoacetate. The bibliography includes 73 references. [ABSTRACT FROM PUBLISHER]

[Display omitted] • TA-1 and TA-2 are efficient inhibitors for the copper corrosion in 1 M HNO 3 solutions, they act as mixed-type inhibitors. • The inhibition proficiency upsurges with increasing concentrations, the %IE in approve with the order of: TA-1 ˃ TA-2. • The adsorption of the triazine derivatives on the copper surface in 1 M HNO 3 solutions seeks Langmuir adsorption isotherm. • The XPS analysis was carried out to endorse the adsorption of the TA-1 on the copper metal. • A good accord between the theoretical and experimental data. This study evaluated, the corrosion inhibition behavior of some triazine derivatives, including 2,4-diphenyl-6-((1E)-1-(4-phenyl-2-(phenyldiazenyl)tetraaz-3-en-1-ylidene)ethyl)-2,3,4,5-tetrahydro-1,2,4-triazine (TA-1) and 2,4-diphenyl-6-((E)-1-((E)-4-phenyltetraaz-2-en-1-ylidene) ethyl)-2,3,4,5-tetrahydro-1,2,4-triazine (TA-2) were surveyed for copper corrosion in 1 M HNO 3 solutions by using electrochemical methods, such as potentiodynamic polarization (PP) and electrochemical impedance spectroscopy (EIS). PP plots showed that the examined (TA-1) and (TA-2) are virtuous compounds for the copper corrosion inhibition in 1 M HNO 3 solutions, and they assume the role of mixed-type inhibitors. Double layer capacitances reduce referring to blank solution once the examined inhibitors were added. The inhibition efficiency reached maximum values of TA-1 and TA-2 are 91.4%, 88.9 at 10-4M, respectively. The copper surface processed with the examined components was anatomized by X-ray photoelectron spectroscopy to verify the formation of adsorbed protective barrier. The examined components followed Langmuir adsorption isotherm; they were adsorbed on copper through chemisorption adsorption. Density functional theory (DFT) calculations and MC simulations were performed to assist the adsorption characteristics and the mechanism of corrosion inhibition using the examined inhibitors. Moreover, the examined inhibitors were used as adsorbate on the Cu (1 1 1) surface and, the adsorption energy was detected on copper exterior. [ABSTRACT FROM AUTHOR]

A series of new thiophene derivatives was prepared through nucleophilic substitution reactions of the precursor N-(4-substituted-phenyl)-5-(2-chloroacetamido)-4-cyano-3-methylthiophene-2-carboxamides 4a and 4b with different sulfur and/or nitrogen nucleophilic reagents (namely; mercaptoacetic acid, 2-mercaptobenzothiazole, 5-(phenylamino)-1,3,4-thiadiazole-2-thiol, 2-mercapto-4,6-dimethylnicotinonitrile, 3-arylazo-4-mercapto-4-(phenylamino)-but-3-en-one derivatives, ammonium thiocyanate, piperidine and/or morpholine). The structures of the prepared thiophene compounds were characterized by spectral analysis. Their cytotoxicity was evaluated against two human cancer cell lines (HepG2 and MCF-7) and indicated promising results. Pretreatment of HepG2 cells with the tested compound 4b sensitized the cells to the cytotoxicity of sorafenib, leading to a significant decrease in the IC50 from 3.9 to 0.5 μM. [ABSTRACT FROM AUTHOR]

Abstract: New antipyrinylazo dyes were prepared by diazocoupling of 4-antipyrinyl diazonium chloride with a variety of coupling components e.g. thiazole, thiophene, pyridone, and pyrazole moieties. The synthesized dyes were characterized by UV–visible absorption, IR, 1H NMR, and MS spectroscopy. These dyes were applied as disperse dyes for dyeing polyester fabrics and their fastness properties were evaluated. Also the position of color in CIELAB coordinates (L*, a*, b*, H*, C*) was assessed. [Copyright &y& Elsevier]

A combination of tetrachlorosilane and zinc chloride in dichloromethane as an efficient and ambient binary reagent to promote a one-pot amidoalkylation reaction of enolizable ketones, aromatic aldehydes with acetonitriles, or benzonitrile have been developed. The newly synthesized β-acetamidoketones 3 and β-benzamidoketones 5 were obtained in good yields. [ABSTRACT FROM AUTHOR]

A new route for the synthesis of β -acylaminoketones containing a thiophene ring through multicomponent condensation reaction of different ketones, different aldehydes, and different nitriles with tetrachlorosilane (TCS) and zinc chloride as the binary reagent is described. [ABSTRACT FROM AUTHOR]

Herein, the constructing synthon 3‐oxobutanamidothiophene derivatives 2 a and 2 b were synthesized and utilized for building a wide variety of pyran, thiazole, pyrazole or pyrimidine ring heterocyclic compounds that can be used as anticancer medications. 3‐Oxobutanamidothiophene derivatives 2 a,b were coupled with 4‐substitutedphenyl diazonium chloride to produce the corresponding hydrazones derivatives 3 a–f. Various thiophene‐pyran derivatives 4 a,b were synthesized through the treatment of thiophene components 2 a,b with different arylidene‐malononitrile. 2‐Aminothiophene derivatives 5 were prepared via Gewald's reaction between 2 a,b, elemental sulfur, and various activated nitrile derivatives. The 3‐oxobutanamidothiophene derivatives 2 a,b were reacted with PhNCS and the potassium salt intermediates 6 a,b with ethyl bromoacetate to pick up the corresponding thiophene‐thiazolidin‐4‐one derivatives 7. Treatment of the conforming thiocarbamoyl compounds 8 a,b, which undergo heating with three types of α‐halogenated reagents to afford the corresponding substitutedthiophene‐3‐carboxamides 9 a,b. Condensation of keteneN,S‐acetals 10 a,b with hydrazines furnished the thiophene‐pyrazole‐4‐carboxamide hybrids 11 a,b, while condensation with urea and/or thiourea afforded the corresponding thiophene‐pyrimidine‐5‐carboxamides 12 a,b. The recently synthesized thiophene compounds were characterized there in vitro anticancer properties against HepG2 (hepatocellular carcinoma) and MDA‐MB‐231 (breast cancer) were evaluated. Molecular docking was also performed to predict the binding modes of synthesized derivatives with the good anticancer results designed as potential inhibitors for a specific target. [ABSTRACT FROM AUTHOR]

Reactions of 3,5-diphenylcyclohex-2-en-1-one (1) with several chemical reagents have led to a variety of novel biologically active hydrazones, arylidene derivatives and heterocycles. The newly synthesized compounds have been tested as antioxidants and in vitro inhibitors of Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli, and fungus Candida albicans. The most active products have been evaluated for their cytotoxicity and MIC values. The results indicate that the majority of compounds exhibit significant potency. [ABSTRACT FROM AUTHOR]

Diazotization of the hydrazone (2), derived from 6‐Acetyl‐2,4‐diphenyl‐tetrahydro‐1,2,4‐triazine (1), gave the corresponding 1‐chlorotriaz‐2‐enylidene derivative 3. Coupling of 3 with resorcinol and 2‐naphthol afforded the triazenes 4 and 5. The synthesis of tetrahydro‐1,2,4‐triazine incorporating triazene and piperidine or piperazine moieties has been achieved by coupling of 3 with the respective amine. Coupling of 3 with aromatic amines and polyhydroxy amines gave the corresponding tetraazenes. Whereas, coupling with the hydrazone 2 afforded pentaazene. In addition, the coupling of aryl diazonium salts with the hydrazone 2 was investigated. [ABSTRACT FROM AUTHOR]

Review: 73 refs. [ABSTRACT FROM AUTHOR]

A concise one-step procedure was developed for the synthesis of some newer tetrahydro-4 H-benzo[1,3- e]oxazines and β-acylamino ketone derivatives via condensation of cyclohexanone derivative with different aromatic aldehydes and nitriles in the presence of tetrachlorosilane/zinc chloride (TCS/ZnCl2) reagent mixture under ambient conditions. Docking studies for the synthesized benzo-oxazine derivatives were designed and a model of highly active derivatives was mapped for the antimicrobial screening. [ABSTRACT FROM AUTHOR]

such as pyridopyrimidodiazepine (IV), pyrazolopyridopyrimidine (V), tetrazolopaphthyridine (VI) et al. [ABSTRACT FROM AUTHOR]

New approaches for the synthesis of some heterocyclic compounds, such as the pyridopyrimidodiazepine derivative 3, pyrazolopyrido[1,2-a]pyrimidine derivative 4, tetrazolo[1.5-a][1,8]naphthyridine derivative 9, pyrazolylpyrido[1,2-a]pyrimidine derivatives 10a, 10b, 12, pyrrolopyrido[1,2-a]pyrimidine derivatives 14a, 14b, 14c, 14d, and 16a, 16b, starting from 2-chloro-4 H-4-oxo-pyrido[1,2-a]pyrimidine ( 1), are described. [ABSTRACT FROM AUTHOR]