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.     

Using dextromethorphan potentiometric membrane sensor in analysis of dextromethorphan hydrobromide in pharmaceutical formulation and urine; Computational study

Dextromethorphan (DXM) is an antitussive (cough Hyj/UA suppressant) drug found in many cough medicines. Dextromethorphan has also found other uses in medicine, ranging from pain relief to psychoactive applications. In this study, a potentiometric liquid membrane sensor for simple and fast determination of dextromethorphan hydrobromide in pharmaceutical formulation and urine was constructed. For the membrane preparation, DXM-tetraphenylborate complexes were employed as electroactive materials in the membrane. The wide linear range (10⁻⁶–10⁻² M), low detection limit (1 × 10⁻⁶ M), and fast response time (∼5 s) characterize the proposed sensors. Validation of the method shows suitability of the sensors for applications in the determination of dextromethorphan hydrobromide in pharmaceutical formulation and urine.     

Optical buffer performance enhancement using Particle Swarm Optimization in Ring-Shape-Hole Photonic Crystal Waveguide

Ring-Shape-Hole Photonic Crystal Waveguides (RSHPCW) is a popular structure in designing optical buffers attracted many attentions recently. There are some parameters such as the radii of holes and pillars next to the defect that have significant effects on slow light properties. Consequently, one of the promising methods for effectively slowing the light speed down and controlling dispersion is to optimize these parameters, which is the motivation of this study. Particle Swarm Optimization (PSO) algorithm is one of the best proposed heuristic optimization algorithms in Artificial Intelligence applied to many engineering problem. In this work, this algorithm is employed to find the best values of the aforementioned radii for maximizing Normalized Delay-Bandwidth Product (NDBP) of RSHPCW structure as the first systematic optimizer. Calculation results show that there are 34% and 41% improvement in NDBP and bandwidth compared to the previous works, very substantial achievements in this area.     

A molecular modeling study on full-length insulin: insight into initial events of amyloid formation

Studies on the structure and physico-chemical properties of amyloid fibrils are important with regard to a better understanding of amyloid diseases such as Alzheimer’s. Insulin is used as a protein model which is easily driven toward amyloid formation. In the present study, five sets of 15 ns molecular dynamics simulations were performed on insulin in order to observe the initial structural changes that occur in the process of amyloid formation. Potential energy, RMSD, and secondary structure percentage of sampled structures were analyzed in all experiments. Common residues that undergo the first conformational changes were detected to be S9 and V10 of the A chain, as well as G8 and S9 of the B chain. The RMSD of truncated insulin increased much more than full-length insulin to about 18 Å. However, the beta-sheet structures percentage of full-length insulin, which is an indicative of amyloid formation, was higher than the truncated form in the presence of salt. This is indicative of the importance of the five residues of the B chain C-terminal in the insulin misfolding process. Overall, simulating full-length insulin under high temperature and in the presence of KCl could be used to assess amyloid formation and potential amyloid inhibitors of this protein.     

Atomic absorption spectrometry for the automatic indirect determination of ascorbic acid based on-the reduction of manganese dioxide.

A new and simple flow injection method followed by atomic absorption spectrometry has been developed for the indirect determination of ascorbic acid. The proposed method is based on oxidation of ascorbic acid to dehydroascorbic acid using a solid-phase manganese dioxide (30% m/m suspended on silica gel beads) reactor. The flow of the sample through the column reduces the MnO2 to Mn(II) in an acidic carrier stream of 6.3 mM HNO3 (pH 2.2) with flow rate of 4.0 ml/min at room temperature; Mn(II) is measured by atomic absorption spectrometry. The absorbance of Mn(II) is proportional to the concentration of ascorbic acid in the sample. The calibration curve was linear up to 30 mg/L, with a detection limit of 0.2 mg/L for a 220 microL injected sample volume. The developed procedure was found to be suitable for the determination of AsA in pharmaceuticals and foods with a relative standard deviation better than 1.09% and a sampling rate of about 95 h(-1). The results exhibit no interference from the presence of large amounts of organic compounds. The reliability of the method was established by parallel determination against the 2,6-dichlorophenol-indophenol methods.     

Chemical composition and antibacterial activity of essential oils from leaves, stems and flowers of Salvia reuterana Boiss. grown in Iran

The essential oils obtained by hydrodistillation of the leaves, stems and flowers of Salvia reuterana (Lamiaceae) were analysed by GC and GC/MS. Germacrene D and beta-caryophyllene were the major constituents in all the three oils: (28.5, 27.7 and 32.5%) and (15.5, 11.4 and 16.6%), respectively. Bicyclogermacrene (10.2 and 13.2%) was also prodominated in the stem and flower oils. The composition of the oils was mostly quantitativel rather than qualitatively different. All the oils consisted mainly of sesquiterpenes and a small percentage of non-terpenoid compounds. In all the three oils, monoterpenes were in a concentration less than 0.5%. Antibacterial activity was determined by the measurement of growth inhibitory zones.     

Vinylazides: versatile synthons and magical precursors for the construction of N-heterocycles

Molecular Diversity - Nowadays, application of vinylazides as precursors is a key method for the construction of N-heterocycles in organic synthesis. These versatile three-atom synthons can be...     

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.     

A new recyclable Pd catalyst supported on vertically aligned carbon nanotubes for microwaves-assisted Heck reactions

Palladium supported on vertically aligned multi-walled carbon nanotubes (Pd/VA-CNTs) is used as catalyst for the C-C coupling reactions of p-iodonitrobenzene with styrene and ethyl acrylate under microwaves irradiation. Pd/VA-CNTs catalyst exhibits higher activity compared to Pd supported on activated charcoal, under the same reaction conditions. Due to the microwaves irradiation, the kinetics of the reaction is strongly accelerated compared to that obtained with a traditional heating mode. The macroscopic form of aligned CNTs support allows an easy recovery of the catalyst, avoiding a costly post-reaction filtration. In addition, the interaction between the active phase and the support leads to the negligible leaching of palladium during recycling tests. The observed results indicate that Pd/CNTs is a recyclable and stable heterogeneous catalytic system.