DESIGN, SYNTHESIS, MOLECULAR DOCKING, AND EVALUATION OF CHROMONE BASED TETRAZOLE DERIVATIVES

Objectives: The objective of this research work was to design, synthesize, study the molecular docking, and evaluate the antimicrobial activity of some novel substituted 2-(Phenylamino)-3-(1H-tetrazol-5-yl)-4H-chromen-4-one derivatives (12a-h). Methods: In the present work, 3-Formylchromones were transformed into pharmacologically active substituted 2-(Phenylamino)-3-(1H-tetrazol-5- yl)-4H-chromen-4-one derivatives (12a-h) through a multistep reaction. Initially, synthesis of the substituted 4-Oxo-2-(phenylamino)-4H-chromone-3- carbaldehydes (9a-h) was carried out using substituted acetophenones (6a-h) as starting material and by employing an earlier reported method (1,3-dipolar cycloaddition reaction). Then, these synthesized compounds were converted into respective oximes (10a-h).The obtained oximes (10a-h) were further converted into nitriles (11a-h) which were finally subjected to concerted cycloaddition through stepwise addition of neutral or anionic azide species to furnish final substituted 2-(Phenylamino)-3-(1H-tetrazol-5-yl)-4H-chromen-4-one derivatives (12a-h). All the newly synthesized compounds (12a-h) and a reference compound (ciprofloxacin) were docked into the active site of TyrRS (PDB: 1JIK) by means of the BioPredicta module of VLife MDS. The synthesized compounds (12a-h) were also evaluated in vitro for their antibacterial (against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, and Escherichia coli bacterial stains) and antifungal activities (against Aspergillus niger and Candida albicans fungal strains) using Zone of Inhibition method. Results: The formation of substituted 2-(Phenylamino)-3-(1H-tetrazol-5-yl)-4H-chromen-4-one derivatives (12a-h) was confirmed through their spectral analysis, that is, 1H-NMR, 13C-NMR, and Mass spectroscopy. During docking study, the recorded molecular binding interactions revealed that all the newly synthesized compounds (12a-h) interacted well with binding site of the enzyme. The synthesized compounds were also evaluated in vitro for their antibacterial (against S. aureus, B. subtilis, P. aeruginosa, and E. coli bacterial stains) and antifungal activities (against A. niger and C. albicans fungal strains). All the synthesized compounds exhibited moderate-to-potent antimicrobial activities. Conclusions: All the synthesized compounds exhibited moderate-to-potent antimicrobial activity

Multi-page Menu Recommendation in Cascade Model with Externalities

In this paper, we consider a variant of the cascade model of customer behavior, where the customer browses through a multi-page menu, scanning each page from top to the bottom predominantly. Each page is assigned items belonging to a specific class out of a set of such classes. He/she adopts the first most attractive content, which generates some revenue. We aim at maximizing the total revenue by finding an optimal index-based policy for ranking the content when the customer preferences and patience levels are known. When we have no prior information about the customer, we design the Online Greedy Algorithm (OGA) which we prove to be asymptotically converging to the optimal solution with probability one. We also provide high probability finite-time convergence bounds for the same

Synthesis, characterization and pharmacological evaluation of (Z)-2-(5-(biphenyl-4-yl)-3-(1-(imino)ethyl)-2,3-dihydro-1,3,4-oxadiazol-2-yl)phenol derivatives as potent antimicrobial and antioxidant agents

The oxadiazole pharmacophore is considered a viable lead structure for the synthesis of more efficacious and broad spectrum antimicrobial agents. The significance of this study was to prepare various oxadiazole derivatives by introducing the 1,3,4 oxadiazole core into several molecules to explore the possibilities of some altered biological activities. Therefore, the study presents the synthesis, antimicrobial and antioxidant evaluation of a series of 1,3,4 substituted oxadiazole derivatives. Antimicrobial evaluation revealed that eighteen compounds were able to display variable growth inhibitory effects on the tested Gram-positive bacteria Bacillus subtilis and Staphylococcus aureus, Gram-negative bacteria Pseudomonas aeruginosa and Escherichia coli and fungal strains Candida albicans and Aspergillus niger. Among the synthesized derivative analogues 6f, 6l and 6r were found to be the most effective antibacterial agents. While the compounds 6c, 6l and 6q were found to be the most promising antifungal agents. On the other hand, all the synthesized compounds 6a–6r were subjected to antioxidant activity but only analogues 6l and 6q were found to exhibit potent antioxidant activity. Further compound 6l containing p-nitro phenyl moiety along with oxadiazole pharmacophore proved to be the most active antimicrobial and antioxidant agent

Designing of Peptide Based Multi-Epitope Vaccine Construct against Gallbladder Cancer Using Immunoinformatics and Computational Approaches

Gallbladder cancer (GBC) is an aggressive and difficult to treat biliary tract carcinoma with a poor survival rate. The aim of this study was to design a peptide-based multi-epitope vaccine construct against GBC using immunoinformatics approaches. Three proteins implicated in the progression of GBC were selected for B and T cell epitope prediction and the designing of the potential vaccine construct. Seven CTL, four HTL and six Bcell epitopes along with a suitable adjuvant were selected and connected using linkers for designing the vaccine construct. The secondary and tertiary models of the designed vaccine were generated and satisfactorily validated. A Ramachandran plot of the final 3D model showed more than 90% of the residues in allowed regions and only 0.4% in disallowed regions. The binding affinity of a vaccine construct with TLR 2, 3 and 4 receptors was assessed through molecular docking and simulation. The average numbers of hydrogen bonds for vaccine-TLR 2, 3 and 4 complexes in the simulation were 15.36, 16.45, and 11.98, respectively, and remained consistent over a 100 ns simulation period, which is critical for their function. The results of this study provide a strong basis for further evaluation through in vitro/in vivo experimental validation of the safety and efficacy of the designed vaccine construct