2,3-Dihydrofurans as Potential Cytotoxic and Antibacterial Agents: Tandem Knoevenagel−Michael Cyclization for the Synthesis of 2,3-Dihydrofurans by Using α-Tosyloxy Ketone Precursors

One-Pot Green Synthesis and Biological Evaluation of Dimedone-Coupled 2,3-Dihydrofuran Derivatives to Divulge Their Inhibition Potential against Staphylococcal Thioredoxin Reductase Enzyme

New therapeutic leads are in global demand against multiple drug-resistant Staphylococcus aureus, as presently there is no drug of choice left to treat this pathogen. In the present work, we have designed, synthesized, and in vitro validated dimedone-coupled 2,3-dihydrofuran (DDHF)-based inhibitor scaffolds against Staphylococcal thioredoxin reductase (SaTR), a pivotal drug target enzyme of Gram-positive pathogens. Accordingly, a green multicomponent method that is both efficient and one pot has been optimized to synthesize DDHF derivatives. The synthesized DDHF derivatives were found to inhibit a purified SaTR enzyme. The best inhibitor derivative, DDHF20, inhibits SaTR as a competitive inhibitor for the NADPH binding site at low micromolar concentrations. DDHF20-capped silver nanoparticles are synthesized and characterized, and their bactericidal property has been checked in vitro. Furthermore, detailed in silico-based structure-guided functional studies have been carried out to uncover the plausible mode of action of DDHF20 as a potential anti-Staphylococcal therapeutic lead.

Design, Synthesis and Cytotoxicity of New Coumarin-1,2,3-triazole Derivatives: Evaluation of Anticancer Activity and Molecular Docking Studies

A library of new coumarin-1,2,3-triazole hybrids 7a-l were synthesized from 4-(diethylamino)-2-hydroxybenzaldehyde precursor through a series of reactions including Vilsmeier-Haack reaction and condensation reaction to achieve key intermediate oxime and further performed click reaction by using different aromatic azides. We screened all molecules in silico against crystal structure of Serine/threonine-protein kinase 24 (MST3), based on these results all molecules were screened for their cytotoxicity against human breast cancer MCF-7 and lung cancer A-549 cell lines. Compound 7 b (p-bromo) showed best activity against both cell lines MCF-7 and A-549 with IC50 value of 29.32 and 21.03 μM, respectively, in comparison to Doxorubicin corresponding IC50 value of 28.76 and 20.82 μM. Another compound 7 f (o-methoxy) also indicated good activity against both cell lines with IC50 value of 29.26 and 22.41 μM. The toxicity of all compounds tested against normal HEK-293 cell lines have not shown any adverse effects.

Silver(i)-catalyzed dehydrogenative cross-coupling of 2-aroylbenzofurans with phosphites

The silver(i)-catalyzed dehydrogenative cross-coupling reaction of 2-aroylbenzofurans with phosphites to afford 2-aroyl-3-phosphonylbenzofurans is reported.

Synthesis, Molecular Docking, and Preliminary Evaluation of 2-(1,2,3-Triazoyl)benzaldehydes As Multifunctional Agents for the Treatment of Alzheimer's Disease

We described here our results on the use of thiourea as a ligand in the copper catalysed azide-alkyne cycloaddition (CuAAC) of 2-azidobenzaldehyde with alkynes. Reactions were performed reacting 2-azidobenzaldehyde with a range of terminal alkynes using 10 mol % of copper iodide as a catalyst, 20 mol % of thiourea as a ligand, triethylamine as base, DMSO as solvent at 100 °C under nitrogen atmosphere. The corresponding 2-(1H-1,2,3-triazoyl)-benzaldehydes (2-TBH) were obtained in moderated to excellent yields and according our experiments, the use of thiourea decreases the formation of side products. The obtained compounds were screened for their binding affinity with multiple therapeutic targets of AD by molecular docking: β-secretase (BACE), glycogen synthase kinase (GSK-3β) and acetylcholinesterase (AChE). The three compounds with highest affinity, 5 a (2-(4-phenyl-1H-1,2,3-triazol-1-yl)benzaldehyde), 5 b (2-(4-(p-tolyl)-1H-1,2,3-triazol-1-yl)benzaldehyde), and 5 d (2-(4-(4-(tert-butyl)phenyl)-1H-1,2,3-triazol-1-yl)benzaldehyde) were selected and evaluated on its antioxidant effect, in view of select the most promising one to perform the in vivo validation. Due the antioxidant potential ally to the affinity with BACE, GSK-3β and AChE, compound 5 b was evaluated in a mouse model of AD induced by intracerebroventricular injection of streptozotocin (STZ). Our results indicate that 5 b (1 mg/kg) treatment during 20 days is able to reverse the cognitive and memory impairment induced by STZ trough the modulation of AChE activity, amyloid cascade and GSK-3β expression.

Palladium(ii)-catalyzed synthesis of indenones through the cyclization of benzenecarbaldehydes with internal alkynes

The palladium(ii)-catalyzed carbocyclization of benzenecarbaldehydes with internal alkynes to afford 2,3-disubstituted indenones was reported. The annulation reaction proceeded through the transmetalation of Pd(ii) with an aromatic aldehyde and the insertion of internal alkynes, followed by cyclization via the intramolecular nucleophilic addition of intermediate organopalladium(ii) species to the aldehyde group. This reaction proceeded in moderate to good yields with high regioselectivity.

Silver-catalyzed oxidative 1,2-alkyletherification of unactivated alkenes with α-bromoalkyl carbonyls: facile access to highly substituted 2,3-dihydrofurans

A silver-catalysed C–Br oxidative functionalization/annulative oxygenation process for producing valuable quaternary-carbon-possessing 2,3-dihydrofuran is presented.