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Under ultrasound irradiation, 17 examples of 2-Amino-3-cyano-4H-chromene derivatives were prepared via one-pot three components domino Knoevenagel–Michael condensation reaction of aliphatic/aromatic/heterocyclic aldehydes, malononitrile, and α-naphthol/β–naphthol/resorcinol in the presence of Fe3O4‐supported sulfonated graphene oxide as a green and magnetically separable nanocatalyst in H2O: EtOH (1:1) solvent system. FT-IR, TGA, SEM, and XRD were used to evaluate the catalyst. The current protocol is appealing because of high atom economy (95%), excellent yields (88-95%), its short reaction time, waste-free conditions, cost-effectiveness, use of a nontoxic solvent, lack of high temperature for reflux, non-chromatographic purification of products, recyclability of catalyst, etc. In-silico studies were conducted on the selected proteins DNA gyrase (1KZN) and CYP51 (4WMZ) to study the docking interactions with highest docking scores 4h (−8.8 kcal/mol) and 4e (−10.1 kcal/mol), respectively. ADME and Toxicity analysis of docked compounds and reference drugs were also done.HighlightsRoom temperature and ultrasound assisted three-component synthesisSynthesis of biological important 4H-chromene derivatives in H2O: EtOH (1:1) solventHigh yields of products (88–95%) within rapid reaction time (10–15 min).High atom economy 95%.Avoid of column chromatographyIn-silico studiesEasy and fast work upMagnetically separable and reusable catalyst. Room temperature and ultrasound assisted three-component synthesis Synthesis of biological important 4H-chromene derivatives in H2O: EtOH (1:1) solvent High yields of products (88–95%) within rapid reaction time (10–15 min). High atom economy 95%. Avoid of column chromatography In-silico studies Easy and fast work up Magnetically separable and reusable catalyst.

Abstract: 1,5-Disubstituted tetrazoles are vital drug-like scaffolds usually encountered as valuable bioisosteres of the cis-amide bond. In this article, we reported the synthesis of some novel medicinally relevant pyrazole centered 1,5-disubstituted tetrazoles using ultrasound irradiation via a one-pot 4-C reaction from various pyrazole originated aldehyde, amine, isocyanide, and sodium azide. All the synthesized derivatives were characterized by IR, 1H NMR, 13C NMR, spectroscopic techniques, and mass analysis. This ultrasound-assisted green protocol has several advantages like mild reaction condition, high yield, catalyst and solvent-free reaction protocol, 15 minutes reaction time and easy workup.

Novel 6-arylethyl-1,2,4-trioxanes6a-i and 7a-i are easily accessible in one step from the diimide reduction of 6-arylvinyl-1,2,4-trioxanes 5a-i. All of these new trioxanes were assessed for their oral antimalarial activity against multidrug-resistant Plasmodium yoelii nigeriensis in a Swiss mice model. Most of the saturated trioxanes 6c, 6f, 6g, 6h, and 6i, the active compounds of the series, provided 100% protection to the malaria-infected mice at a dose of 24 mg/kg × 4 days. Further, trioxane 6i, the most active compound of the series, also showed 100% protection even at a dose of 12 mg/kg × 4 days and 20% protection at a dose of 6 mg/kg × 4 days. In this model, β-arteether provided 100% protection at a dose of 48 mg/kg × 4 days and only 20% protection at a dose of 24 mg/kg × 4 days via the oral route, which was found to exhibit 4-fold antimalarial activity compared with the currently used drug β-arteether.

The dichalcogenide ligated molecules in catalysis to produce molecular hydrogen through electroreduction of water are rarely explored. Here, a series of heterometallic [Ag

In the current research, we envisaged the synthesis of bis-heterocycles containing the dihydroisoxazole ring by [3 + 2] cycloaddition of VECs (vinyl ethylene carbonates) and nitrile oxides, assisted by a Pd catalyst. Herein we explored hydroximoyl chlorides as versatile precursors for the

Carbon quantum dots (CQDs) are promising carbonaceous nanomaterials fortuitously discovered in 2004. CQDs are the rising stars in the nanotechnology ensemble because of their unique properties and widespread applications in sensing, imaging, medicine, catalysis, and optoelectronics. CQDs are notable for their excellent solubility and effective luminescence and, as a result, they are also known as carbon nanolights. Many strategies are used for the efficient and economical preparation of CQDs; however, CQDs prepared from waste or green sustainable methods have greater requirements due to their safety and ease of synthesis. Sustainable chemical strategies for CQDs have been developed, emphasizing green synthetic methodologies based on 'top-down' and 'bottom-up' approaches. This review summarizes many such studies relevant to the development of sustainable methods for photoluminescent CQDs. Furthermore, we have emphasized recent advances in CQDs' photoluminescence applications in chemical and biological fields. Finally, a brief overview of synthetic processes using the green source and their associated applications are tabulated, providing a clear understanding of the new optoelectronic materials.

Catalyst free synthesis of 6-aryl phenanthridines and amides through an electrochemical reaction is reported in this study. The coupling reaction proceeds by the cathodic reduction of in situ formed diazonium ions, which are formed from anilines and an alkyl nitrite. The generated aryl radical diazonium ions coupled from isocyanides furnished the desired products in good yields. This cascade reaction was conducted in an undivided cell equipped with an RVC as the anode and Pt as the cathode using nBu4NBF4 as the electrolyte at room temperature. A series of detailed mechanistic studies have also been performed, including a radical clock experiment and cyclic voltammetry analysis.

The concept of gene vectors for therapeutic applications has been known for several years, but it is far from revealing its actual potential. With the advent of hollow cylindrical carbon nanomaterials such as carbon nanotubes (CNTs), researchers have invented several new tools to deliver genes at the required site of action in mammalian and plant cells. The ease of diversified functionalization has allowed CNTs to be by far the most adaptable non-viral vector for gene therapy. This Minireview addresses the dexterity with which CNTs undergo surface modifications and their applications as a potent vector in gene therapy of humans and plants. Specifically, we will discuss the new tools that scientific communities have invented to achieve gene therapy using plasmid DNA, RNA silencing, suicide gene therapy, and plant genetic engineering. Additionally, we will shed some light on the mechanism of gene transportation using carbon nanotubes in cancer cells and plants.

A mechanistic approach to understand the course of metabolism for synthetic 1,2,4-trioxanes, potent antimalarial compounds, to evaluate their bioavailability for antimalarial action has been studied in the present work. It is an important parameter to study the course of metabolism of a drug candidate molecule when administered via oral route during its journey from oral intake to its target site. From the pharmacokinetics point of view, it determines the bioavailability of an active drug or a prodrug at the target point. In this work, synthetic arylvinyl-1,2,4-trioxanes

Indolizine derivatives are prevalent in many synthetic intermediates, pharmaceuticals, and organic materials. Herein, we report a novel electro-oxidative cascade cyclization reaction that uses electricity as the primary energy input to promote the reaction, leading to a series of heterocyclic substituted indolizine derivatives under exogenous-oxidant-free conditions. It is noteworthy that this electrochemical method provides a novel strategy for generating heterocyclic diversity of quinazolinones and quinolines on indolizines. In addition, the sole byproduct in the reaction was molecular hydrogen.

An expeditious synthetic strategy to access functionalized S-thiocarbamates was developed in good to excellent yields and with high current efficiencies. Readily available isocyanides and thiols were used as the starting materials under simple metal- and oxidant-free reaction conditions avoiding an inert atmosphere. The practical application of the present methodology was achieved by electrochemical synthesis of the herbicides prosulfocarb and pebulate. Furthermore, continuous electrochemical flow conditions using a graphite/Pt flow cell were used to obtain S-thiocarbamate compounds on a gram scale within a residence time of 35 min.

A divergent regioselective palladium (II) catalyzed approach through post Ugi cyclization is described. The Ugi adduct underwent intramolecular ortho-hydroarylation via 6-endo-dig cyclization for the direct access to 4-aryl-2-quinolones. Incorporation of iodine at the C-3 position of 2-quinolone followed by Suzuki-Miyaura coupling results into the more diversified 3,4-diaryl-2-quinolones.

Human malaria, one of the most striking, reemerging infectious diseases, is caused by several types of Plasmodium parasites. Whilst advances have been made in lowering the numbers of cases and deaths, it is clear that a strategy based solely on disease control year on year, without reducing transmission and ultimately eradicating the parasite, is unsustainable. Natural products have served as a template for the design and development of antimalarial drugs currently in the clinic or in the development phase. Artemisinin combine potent, rapid antimalarial activity with a wide therapeutic index and an absence of clinically important resistance. The alkylating ability of artemisinin and its semi-synthetic analogues toward heme related to their antimalarial efficacy are underlined. Although impressive results have already been achieved in malaria research, more systematization and concentration of efforts are required if real breakthroughs are to be made. This review will concisely cover the clinical, preclinical antimalarial and current updates in artemisinin based antimalarial drugs. Diverse classes of semi-synthetic analogs of artemisinin reported in the last decade have also been extensively studied. The experience gained in this respect is discussed.

A new series of 1,2,4-trioxanes 9a1-a4, 9b1-b4, 10–13 and 9c1-c4 were synthesized and evaluated against multidrug-resistant Plasmodium yoelii nigeriensis in Swiss mice via oral and intramuscular (i.m.) routes. Adamantane-based trioxane 9b4, the most active compound of the series, provided 100% protection to the infected mice at the dose 48 mg/kg × 4 days and 100% clearance of parasitemia at the dose 24 mg/kg × 4 days via oral route. Adamantane-based trioxane 9b4, is twice active than artemisinin. We have also studied the photooxygenation behaviour of allylic alcohols 6a-b (3-(4-alkoxynaphthyl)-but-2-ene-1-ols) and 6c (3-[4-(tert-butyl-dimethyl-silanyloxy)-naphthalen-1-yl]-but-2-en-1-ol). Being behaving as dienes, they furnished corresponding endoperoxides, while behaving as allylic alcohols, they yielded β-hydroxyhydroperoxides. All the endoperoxides (7a-c) and β-hydroxyhydroperoxides (8a-c) have been separately elaborated to the corresponding 1,2,4-trioxanes, except from endoperoxide 7c. It is worthy to note that TBDMS protected naphthoyl endoperoxide 7c unable to deliver 1,2,4-trioxane, which demonstrated the strength of the O-Si bond is not easy to cleave under acidic condition.

Malaria epidemics represent one of the life-threatening diseases to low-income lying countries which subsequently affect the economic and social condition of mankind. In continuation in the development of a novel series of 1,2,4-trioxanes 13a1-c1, 13a2-c2, and 13a3-c3 have been prepared and further converted into their hemisuccinate derivatives 14a1-c1, 14a2-c2, and 14a3-c3 respectively. All these new compounds were evaluated for their antimalarial activity against multidrug-resistant Plasmodium yoelii nigeriensis in mice by both oral and intramuscular (im) routes. Hydroxy-functionalized trioxane 13a1 showed 80% protection and its hemisuccinate derivative 14a1 showed 100% protection at a dose of 48 mg/kg × 4 days by both routes, which is twice active than artemisinin by oral route.

Twenty-five new hits of spirooxindole analogs 8a–y engrafted with indole and pyrazole scaffolds were designed and constructed via a [3+2]cycloaddition (32CA) reaction starting from three components: new chalcone-based indole and pyrazole scaffolds 5a–d, substituted isatins 6a–c, and secondary amines 7a–d. The potency of the compounds were assessed in modulating cholinesterase (AChE) activity using Ellman’s method. Compounds 8i and 8y showed the strongest acetylcholine esterase inhibition (AChEI) with IC50 values of 24.1 and 27.8 μM, respectively. Molecular docking was used to study their interaction with the active site of hAChE. peerReviewed

Background: Thymol is a natural phenolic monoterpenoid widely used in pharmaceutical and food preservative applications. Thymol isomeric with carvacrol, extracted primarily from Thymus species (Trachyspermum ammi) and other plants sources such as Baccharisgrise bachii and Centipeda minima, has ethnopharmacological characteristics. Methods: This review was prepared by analyzing articles published on thymol moiety in last decade and selected from Science Direct, Scopus, Pub Med, Web of Science and SciFinder. The selected articles are classified and gives brief introduction about thymol and its isolation, illustrates its natural as well as synthetic sources, and also therapeutic benefits of thymol worldwide Results: Thymol has been covering different endeavors such as antimicrobial, antioxidant, antiinflammatory, antibacterial, antifungal, antidiarrhoeal, anthelmintic, analgesic, digestive, abortifacient, antihypertensive, spermicidal, depigmenting, antileishmanial, anticholinesterase, insecticidal and many others. This phenolic compound is among the essential scaffolds for medicinal chemists to synthesize more bio-active molecules by further derivatization of the thymol moiety. Conclusion: Thymol is an interesting scaffold due to its different activities and derivatization of thymol is proved to enhance its biological activities. However, more robust, randomised, controlled clinical trials would be desirable with well-characterised thymol preparations to corroborate its beneficial effects in diseased patients. Moreover, in view of the potential use of thymol and thymol-rich essential oils in the treatment of human infections, comprehensive studies on chronic and acute toxicity and also teratogenicity are to be recommended.

This work discloses an electrochemical oxidative cross-coupling of amines with aryl and aliphatic isocyanides. In an undivided cell, the reaction proceeds without involving any transition-metal catalyst, oxidant, or toxic reagents providing carbodiimides in good yields, thereby circumventing stoichiometric chemical oxidants, with H2 as the only byproduct. Moreover, carbodiimides were in situ converted into unsymmetrical ureas in moderate to good yields using an electricity ON-OFF strategy.

Novel hydrazone derivatives 10a-m were prepared from N-Amino-11-azaartemisinin (9) and screened for their antimalarial activity by oral and intramuscular (i.m.) routes against multidrug-resistant Plasmodium yoelii in Swiss mice model. Several of the hydrazone derivatives showed higher order of antimalarial activity. Compounds 10b, 10g, 10m provided 100% protection to the infected mice at the dose of 24 mg/kg × 4 days via oral route. Fluorenone based hydrazone 10m the most active compound of the series, provided 100% protection at the dose of 6 mg/kg × 4 days via intramuscular route and also provided 100% protection at the dose of 12 mg/kg × 4 days via oral route. While artemisinin gave 100% protection at 48 mg/kg × 4 days and only 60% protection at 24 mg/kg × 4 days via intramuscular (i.m.) route. Compound 10m found to be four-fold more active than artemisinin via intramuscular route.

A method for the synthesis of 2-aminopyrimidines from readily available 3,4-dihydropyrimidine-2(1H)-thiones via a palladium-assisted C–S activation and N–H insertion reaction is developed. The process provides an access to a variety of highly diverse 2-aryl(alkyl)-aminopyrimidine adducts in good yields.

Correction for ‘Pd-Catalysed [3 + 2]-cycloaddition towards the generation of bioactive bis-heterocycles/identification of COX-2 inhibitors via in silico analysis’ by Elagandhula Sathish et al., Org. Biomol. Chem., 2022, 20, 4746–4752, https://doi.org/10.1039/D2OB00467D.

Two rationally designed β-carboline–imidazopyridine hybrid chromofluorescent sensors S1 and S2 have been successfully synthesized and evaluated for the selective sensing of metal ions and anions. The synthesized sensors selectively sense copper ions through a significant color change from colorless to yellow along with a shift in their absorption spectra and enhancement in their emission intensities to ‘turn on’ the fluorescence mode in preference to other metal ions. Moreover, sensors S1 and S2 also recognize fluoride ions via H-bond interaction and subsequent deprotonation to elicit a color change from colorless to yellow conspicuous to the naked eye. Detailed UV-visible analyses revealed that the sensors interact with copper ions in a 1 : 1 binding stoichiometry with a detection range of 10−7 M. In addition, competing binding studies by UV-visible analyses revealed that the sensors exhibit more selectivity toward copper ions in comparison to fluoride ions. These experimental results were further corroborated by DFT (Density Functional Theory) calculations.

A highly sensitive coumarin-thiophene hybrid chemosensor (CZT) has been successfully designed for sensing of H2O2 and aluminium ion in physiological condition. A large stoke shift and significant enhancement in fluorescence spectra was recorded at λem = 505 nm when sensor was tested with hydrogen peroxide. In the sensing of H2O2, increase in emission peak was linearly depend on concentration of hydrogen peroxide in the range of 50 μM to 2.0 mM which results the detection limit of 1.5 × 10−7 M. Furthermore, colorimetric and spectrophotometric studies reveal that reported sensor had potential to sense Al3+ ion selectively over other tested competitive cations and sensitivity for Al3+ was not affected by coexistent of tested metal ions with detection limit of 1.14 × 10−6 M which is lower than WHO recommendation. The Job's continuation variation plot demonstrated that sensor CZT binds with Al3+ ion via 1:1 binding stoichiometry.

Silver(I) ferrocenyl dithiophosphonato [Ag{S2P(OiPr)Fc}]n I, [Fc = Fe(η5-C5H4)(η5-C5H4)] 1D polymer was yielded via a ligand exchange reaction between silver nanocluster [Ag21(S2P(OiPr2)12)]PF6 and monoanionic [S2P(OiPr)Fc]¯ ligand. As per molecular stoichiometry of 1, a direct reaction between [Ag(CH3CN)4]PF6 and [S2P(OiPr)Fc]− was performed in methanol solvent and surprisingly, generate a tetrahedral Ag4{S2P(OiPr)Fc}4 2 cluster instead of 1. Both (1 and 2) clusters are the novel example of homoleptic Ag(I) complexes supported by ferrocenyl dithiophosphonates. Molecular structure of these clusters was unequivocally established by single crystal X-ray crystallographic analyses and supported by the ESI-MS, and 1H and 31P NMR spectroscopy. Structural elucidations reveal that compound 1 has subsequently Ag2S2 square plane and Ag2S4P2 twisted boat units to build a long chain 1D polymer. The cluster 2 exhibits with a tetrahedral Ag(I) core framed by four [S2P(OiPr)Fc]− ligands. interstingly, the [S2P(OiPr)Fc]− ligand display a trimetallic triconnective (η3; µ1, µ2) bonding pattern in both molecules. The electrochemical behaviours of both compounds (1 and 2) were studied by using cyclic voltammetry, which shows a single wave for all the peripheral ferrocenes and implies negligible electrostatic factor between all ferrocene moieties.

Metal catalyzed post-Ugi cyclization of bis-amides is reported in this study. Exposure of bis-amides to Pd(II) catalyst triggered the formation of seven-membered benzoxazepinones. This investigation established that changing the catalyst to a Echavarren's gold(I) turned off cyclization to seven member ring and turned on 6-exo-dig annulations to afford family of six-membered benzoxazinones. To support the proposed mechanisms, quantum chemical based density functional theory calculations have been performed and validated. This novel method obtained molecular complexity up to four modular inputs and divergence of two different skeletons. 2D NMR spectroscopic techniques and single crystal X-ray diffraction established the proposed structures.