Recent strategies in the synthesis of thiophene derivatives: highlights from the 2012–2020 literature

Molecular Diversity - Thiophene-based analogs have been fascinated by a growing number of scientists as a potential class of biologically active compounds. Furthermore, they play a vital role for...     

4-Oxobenzo[d]1,2,3-triazin-pyridinium-phenylacetamide derivatives as new anti-Alzheimer agents: design,synthesis, in vitro evaluation,molecular modeling,and molecular dynamic study

Structural Chemistry - A new series of 4-oxobenzo[d]1,2,3-triazin-pyridinium-phenylacetamide hybrids 8a–p was designed, synthesized, and screened as the potential cholinesterase inhibitors...     

Design,synthesis and antibacterial activity evaluation of novel 2-(4-((1-aryl-1H-1,2,3-triazol-4-yl)methoxy)phenyl)2-(2-oxoazetidin-1-yl)acetamide derivatives

In this paper, a novel series of 2-(4-((1-aryl-1H-1,2,3-triazol-4-yl)methoxy)phenyl)2-(2-oxoazetidin-1-yl)acetamide derivatives are synthesized in two steps. The first step involved Ugi multicomponent reaction of β-alanine, o-(propargyl)benzaldehyde and isocyanide derivatives. The product of this step, underwent a click 1,3-dipolar cycloaddition reaction with benzyl azide derivatives. The 2-(4-((1-aryl-1H-1,2,3-triazol-4-yl)methoxy)phenyl)2-(2-oxoazetidin-1-yl)acetamide product was characterized and their antibacterial activities were evaluated against various G-positive (Staphylococcus aureus and Bacillus subtilis) and G-negative (Pseudomonas aeruginosa and Escherichia coli) bacteria, using minimal inhibition concentration. The compounds showed very good antimicrobial activity and a number of products have been more active than ciprofloxacin.     

Experimental and theoretical studies of media effects on copper corrosion in acidic environments containing 2-amino-5-mercapto-1,3,4-thiadiazole

Corrosion behaviour of copper metal in acid solutions (HCl, H₂SO₄ and H₃PO₄) containing 2-amino-5-mercapto-1,3,4- thiadiazole (AMT) was investigated experimentally and theoretically via gravimetric, potentio-dynamic and quantum electrochemical approaches. Similar behavior was observed for H₂SO₄ and H₃PO₄ media, and related to the nature of anions at metal/solution interface. With regard to HCl, however, the rate of corrosion was determined to be low at initial stages, but high later on using an auto-catalyzing mechanism. In the presence of AMT, the experimental studies revealed that this molecule was a good anodic-type inhibitor causing substantial changes in corrosion potential. Moreover, its adsorption obeys the Langmuir isotherm. The values of ΔG _ads were determined and correlated to the inhibitor powers. Finally, the influence of media (anions) on metal corrosion was also investigated from molecular point of view by calculations of the copper-anions interaction using density functional theory.     

Design,synthesis, biological evaluation,and docking study of new acridine-9-carboxamide linked to 1,2,3-triazole derivatives as antidiabetic agents targeting α-glucosidase

A new series of acridine-9-carboxamide-1,2,3-triazole derivatives 7a-m were designed, synthesized, and evaluated as novel α-glucosidase inhibitors. Acridine-9-carboxamide-1,2,3-triazole scaffold has been designed by combination of effective moieties from potent α-glucosidase inhibitors. Most of the synthesized compounds were more potent than standard inhibitor acarbose. Among the title compounds, the most potent compounds were compounds 7j , 7k , and 7a with IC₅₀ values of 120.2 ± 1.0, 151.1 ± 1.4, and 157.6 ± 1.6 μM, respectively (IC₅₀ value of acarbose = 750.0 ± 10.0 μM). Docking study of the most potent compounds demonstrated that these compounds formed stable complexes with α-glucosidase active site. Anti-α-amylase assay of compounds 7j , 7k , and 7a was performed and no activity was observed. in vitro cytotoxicity assay of the latter compounds revealed that these compounds were not cytotoxic toward human normal (HDF) and cancer (MCF-7) cell lines. ADME and toxicity prediction of compounds 7j , 7k , and 7a were also performed.     

Efficient one-pot synthesis of novel 6′,9′-dihydro-2H,7′H-spiro[pyrimidine-5,8′-[1,3]dioxolo[4,5-f]quinoline]-2,4,6(1H,3H)-trione derivatives under mild and “green” reaction conditions

In this paper, an efficient method is introduced for the synthesis of 7′,9′-disubstituted 6′,9′-dihydro-2H,7′H-spiro[pyrimidine-5,8′-[1,3]dioxolo[4,5-f]quinoline]-2,4,6(1H,3H)-trione derivatives under mild and “green” reaction conditions. The method is based on one-pot multicomponent reaction of an aldehyde, barbituric acid, and benzo[d][1,3]dioxol-5-amine in ethanol as a green and environmentally friendly solvent. The reaction has given the products in the highest isolated yield in the presence of acetic acid as catalyst under reflux conditions. Various aldehydes, bearing electron-donating or -withdrawing functionalities have been used under the optimized conditions and successfully gave the desired products (13 examples) in high isolated yields.     

Novel (thio)barbituric-phenoxy-N-phenylacetamide derivatives as potent urease inhibitors: synthesis,in vitro urease inhibition,and in silico evaluations

Structural Chemistry - A novel series of (thio)barbituric-phenoxy-N-phenylacetamide derivatives 7a-l was synthesized and evaluated against Helicobacter pylori urease. The latter assay revealed that...     

Optimal locations and orientations of piezoelectric transducers on cylindrical shell based on gramians of contributed and undesired Rayleigh–Ritz modes using genetic algorithm

In this study, the active vibration control and configurational optimization of a cylindrical shell are analyzed by using piezoelectric transducers. The piezoelectric patches are attached to the surface of the cylindrical shell. The Rayleigh–Ritz method is used for deriving dynamic modeling of cylindrical shell and piezoelectric sensors and actuators based on the Donnel–Mushtari shell theory. The major goal of this study is to find the optimal locations and orientations of piezoelectric sensors and actuators on the cylindrical shell. The optimization procedure is designed based on desired controllability and observability of each contributed and undesired mode. Further, in order to limit spillover effects, the residual modes are taken into consideration. The optimization variables are the positions and orientations of piezoelectric patches. Genetic algorithm is utilized to evaluate the optimal configurations. In this article, for improving the maximum power and capacity of actuators for amplitude depreciation of negative velocity feedback strategy, we have proposed a new control strategy, called “Saturated Negative Velocity Feedback Rule (SNVF)”. The numerical results show that the optimization procedure is effective for vibration reduction, and specifically, by locating actuators and sensors in their optimal locations and orientations, the vibrations of cylindrical shell are suppressed more quickly.     

Benzoylquinazolinone derivatives as new potential antidiabetic agents: α-Glucosidase inhibition,kinetic, and docking studies

Benzoylquinazolinone derivatives 3a–n were synthesized via a simple one-step reaction, and evaluated for in vitro α-glucosidase inhibitory activity. Compounds 3d , 3f–g , 3i , and 3m–n showed more inhibitory activity than standard drug acarbose (IC₅₀ = 750.0 ± 1.5 μM), and among them, compound 3d displayed the highest α-glucosidase inhibitory activity (IC₅₀ = 261.6 ± 0.1 μM). The kinetic analysis of the compound 3d revealed that this compound inhibited α-glucosidase in a competitive manner (K_i = 255 μM). The docking studies were applied to predict binding modes of the synthesized compounds in active site of α-glucosidase.     

Design and synthesis of 2,4-dioxochroman-pyridinium-phenylacetamide derivatives as new anti-Alzheimer agents: in vitro and in silico studies

2,4-Dioxochroman-pyridinium-phenylacetamide derivatives 7a–n were synthesized and evaluated for their in vitro cholinesterase (ChE) inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). Obtained results demonstrated that, among the synthesized compounds, two compounds, 7j and 7k , were more potent than the standard drug donepezil against BuChE and did not show cytotoxicity and carcinogenicity. Furthermore, through molecular modeling and molecular dynamic studies. we showed that these compounds can be located deep in the gorge cavity of BuChE and that they interacted with catalytic residues, acyl, and cholin-binding pockets of this enzyme. Support information