Electro- and Mechanochemical Strategy as a Dual Synthetic Approach for Biologically Relevant 3-Nitro-imidazo-[1,2-]pyridines.

We herein disclose a dual synthetic approach involving electrochemical and mechanochemical strategies for diversely functionalized 3-nitro-2-aryl-immidazo[1,2-]pyridines. Both methods offer a practical and straightforward alternative route for accessing this important class of biologically promising nitrogen-containing heterocycles. Significant advantages of the newly developed methods include mild and energy-efficient reaction conditions, avoidance of transition metal catalysts, external heating and additional oxidants, shorter reaction times, good to excellent yields, broad substrate scope, gram-scale applicability, operational simplicity, and eco-friendliness.

Electrorearranged Difunctionalization of 4-Hydroxy-α-benzopyrones.

We herein report the exploration of an electrosynthetic strategy as a highly efficient and straightforward alternative protocol for accessing diversely substituted and biologically promising alkyl 2-hydroxy-3-oxo-2,3-dihydrobenzofuran-2-carboxylates through an electrorearranged difunctionalization of 4-hydroxycoumarins, involving the singlet oxygen insertion from molecular oxygen, at ambient temperature. The present method is notably more advantageous than the previously reported photochemical conversion regarding yields and reaction times, substrate scope and functional group tolerability, operational simplicity, and scalability.

Practice of green chemistry strategies in synthetic organic chemistry: a glimpse of our sincere efforts in green chemistry research.

This feature article summarises our recent contributions (2019-2023) in designing and developing a handful of promising organic transformations for accessing several diversely functionalised biologically relevant organic scaffolds, following the green chemistry principles, particularly focusing on the application of low-energy visible light, electrochemistry, ball-milling, ultrasound, and catalyst- and additive-free synthetic strategies.

C(sp)-C(sp) Bond Formation through Ligand- and Additive-Free CuO-Mediated Decarboxylative Direct Cross-Coupling of Coumarin-/Chromone-3-carboxylic Acids and Terminal Alkynes.

A practical and efficient method for the synthesis of functionalized 4-(aryl-/heteroaryl-ethynyl)chroman-2-ones and 2-(aryl-/heteroaryl-ethynyl)chroman-4-ones through copper-catalyzed decarboxylative direct cross-coupling of coumarin-/chromone-3-carboxylic acids with terminal alkynes, leading to the formation of C(sp)-C(sp) bonds, has been unearthed. Advantages of this protocol include avoidance of any ligands and bases, a broad substrate scope, tolerance of diverse functional groups, and good to excellent yields.

Mechanochemical Solvent-Free One-Pot Synthesis of Poly-Functionalized 5-(Arylselanyl)-1H-1,2,3-triazoles Through a Copper(I)-Catalyzed Click Reaction.

A mechanochemistry-driven practical and efficient synthetic protocol for accessing diverse series of biologically relevant poly-functionalized 5-(arylselanyl)-1H-1,2,3-triazoles through copper(I)-catalyzed click reaction between aryl/heteroaryl acetylenes, diaryl diselenides, benzyl bromides, and sodium azide has been accomplished under high-speed ball-milling. Advantages of this method include operational simplicity, avoidance of using solvent and external heating, one-pot synthesis, short reaction time in minutes, good to excellent yields, broad substrate scope, and gram-scale applications. Furthermore, synthesized organoselenium compounds were synthetically diversified to biologically promising selenones.

Biological evaluation of the novel 3,3'-((4-nitrophenyl)methylene)bis(4-hydroxy-2H-chromen-2-one) derivative as potential anticancer agents via the selective induction of reactive oxygen species-mediated apoptosis.

Selective initiation of programmed cell death in cancer cells than normal cells is reflected as an attractive chemotherapeutic strategy. In the current study, a series of synthetic bis-coumarin derivatives were synthesized possessing reactive oxygen species (ROS) modulating functional groups and examined in four cancerous and two normal cell lines for their cytotoxic ability using MTT assay. Among these compounds, 3 l emerged as the most promising derivative in persuading apoptosis in human renal carcinoma cells (SKRC-45) among diverse cancer cell lines.

Electrochemical Regioselective C()-H Selenylation and Sulfenylation of Substituted 2-Amino-1,4-naphthoquinones.

A straightforward and efficient electrochemical method for regioselective C()-H selenylation and sulfenylation of substituted 2-amino-1,4-naphthoquinones has been unearthed. This oxidative -coupling reaction avoids using transition metal catalysts, oxidants, and high temperatures. The other notable advantages of this protocol are the tolerance of diverse functional groups, mild reaction conditions at ambient temperature, energy efficiency, good to excellent yields, short reaction times (in minutes), gram-scale applicability, and eco-friendliness.

Catalyst- and Additive-Free C(sp)-H Functionalization of (Thio)barbituric Acids C-5 Dehydrogenative Aza-Coupling Under Ambient Conditions.

A one-pot room-temperature-based three-component reaction strategy has been accomplished to access a new series of bio-relevant barbituric/2-thiobarbituric acid hydrazones from the reaction between barbituric/2-thiobarbituric acids, primary aromatic amines, and -butyl nitrite in an acetonitrile solvent, without the aid of any catalysts/additives. The ambient reaction conditions can efficiently implement the C(sp)-H functionalization of barbituric/2-thiobarbituric acids C-5 dehydrogenative aza-coupling. The process does not require column chromatographic purification; pure products are obtained by simple filtration of the resulting reaction mixture, followed by washing the crude residue with distilled water.

An Updated Review on Biologically Promising Natural Oxepines.

Benzo-oxepines and dibenzo-oxepines, a unique class of naturally occurring secondary metabolites, are distributed mainly in plants and fungi and have received much attention from phytochemists and biologists based on their fascinating structural features and health-promoting functions. This review summarizes 100 oxepine derivatives comprising three categories: benzo-oxepine, dibenzo-oxepine, and pyrano-oxepine. Studies on various structural features and pharmacological activities of oxepine derivatives promote further in-depth research on these potent natural products.

Synthetic antioxidants from a natural source can overtake the oncogenic stress management system and activate the stress‑sensitized death of KSHV‑infected cancer cells.

Synthetic and modified natural derivatives are reported as potential bioactive compounds and are being used therapeutically against various diseases in a widespread manner nowadays. Cancerous cells exhibit high levels of reactive oxygen species (ROS) internally, and thus successfully manage to sustain themselves and proliferate via antioxidative mechanisms that maintain a redox balance. On this note, various antioxidants are applied as anticancer compounds, which strategically affects the ongoing oncogenic stress management system in both a pro‑ and antioxidative manner, resulting in cancer restriction, as well as sustaining cell proliferation via antioxidative mechanisms that promote cancer progression.

Amelioration of oxidative stress mediated inflammation and apoptosis in pancreatic islets by Lupeol in STZ-induced hyperglycaemic mice.

Background: Type 1 Diabetes mellitus initiates by loss of pancreatic activity which affects other major organs leading to multi-organ failure. Lupeol, a novel phytochemical, is emerging as a potent bioactive molecule. However, the effect of lupeol on hyperglycaemia is not clearly understood.

Visible-Light-Promoted Intramolecular C-O Bond Formation via CH Functionalization: A Straightforward Synthetic Route to Biorelevant Dihydrofuro[3,2-]chromenone Derivatives.

A photochemical method for the synthesis of functionalized dihydrofuro[3,2-]chromenones via intramolecular C-H -dehydrogenative oxygenation within a warfarin framework has been unearthed. Advantages of this protocol include abundant sunlight or low-energy visible light as the energy source, mild reaction conditions, and avoidance of metal catalysts.

Screening of Synthetic Heterocyclic Compounds as Antiplatelet Drugs.

Background: Antiplatelet drugs represent the keystone in the treatment and prevention of diseases of ischemic origin, including coronary artery disease. The current palette of drugs represents efficient modalities in most cases, but their effect can be limited in certain situations or associated with specific side effects. In this study, representatives of compounds selected from series having scaffolds with known or potential antiplatelet activity were tested.

Visible Light-Driven and Singlet Oxygen-Mediated Photochemical Cross-Dehydrogenative C-H Sulfenylation of 4-Hydroxycoumarins with Thiols Using Rose Bengal as a Photosensitizer.

A visible light (white light-emitting diode/direct sunlight)-driven photochemical synthesis of a new series of biologically interesting 3-(alkyl/benzylthio)-4-hydroxy-2-chromen-2-ones has been achieved through a cross-dehydrogenative C-H sulfenylation of 4-hydroxycoumarins with thiols at ambient temperature in the presence of rose bengal in acetonitrile under an oxygen atmosphere. The notable features of this newly developed method are mild reaction conditions, energy efficiency, metal-free synthesis, good to excellent yields, use of low-cost materials, and eco-friendliness.

In vivo therapeutic evaluation of a novel bis-lawsone derivative against tumor following delivery using mesoporous silica nanoparticle based redox-responsive drug delivery system.

Herein, we have evaluated the in vivo therapeutic efficacy and systemic toxicity profile of a synthetic anticancer compound [3,3'-((4-(trifluoromethyl)phenyl)methylene)bis(2-hydroxynaphthalene-1,4-dione)]. A multifunctional mesoporous silica nanoparticle (MSN) based drug delivery network was also fabricated which specifically showed targeting nature towards the cancer cell. The mesopores of silica nanoparticles were tagged with phenyl boronic acid (PBA) for targeted drug delivery into tumor tissue.

Visible Light-Induced and Singlet Oxygen-Mediated Photochemical Conversion of 4-Hydroxy-α-benzopyrones to 2-Hydroxy-3-oxo-2,3-dihydrobenzofuran-2-carboxamides/carboxylates Using Rose Bengal as a Photosensitizer.

Development of a visible light-induced and singlet oxygen-mediated green protocol has been accomplished for the first time for the photochemical transformation of 4-hydroxy-α-benzopyrones to a new series of biorelevant 2-hydroxy-3-oxo-2,3-dihydrobenzofuran-2-carboxamides and 2-hydroxy-3-oxo-2,3-dihydrobenzofuran-2-carboxylates using rose bengal as a triplet photosensitizer at ambient temperature. Metal-free one-pot synthesis, broader substrate scope, good-to-excellent yields, use of cost-effective and eco-friendly starting materials and photosensitizer, and energy efficiency are the salient features of this newly developed method.

Series of Functionalized 5-(2-Arylimidazo[1,2-]pyridin-3-yl)pyrimidine-2,4(1,3)-diones: A Water-Mediated Three-Component Catalyst-Free Protocol Revisited.

A water-mediated and catalyst-free practical method for the synthesis of a new series of pharmaceutically interesting functionalized 5-(2-arylimidazo[1,2-]pyridin-3-yl)pyrimidine-2,4(1,3)-diones has been accomplished based on a one-pot multicomponent reaction between arylglyoxal monohydrates, 2-aminopyridines/2-aminopyrimidine, and barbituric/,-dimethylbarbituric acids under reflux conditions. The salient features of this protocol are avoidance of any additive/catalyst and toxic organic solvents, use of water as reaction medium, clean reaction profiles, operational simplicity, ease of product isolation/purification without the aid of tedious column chromatography, good to excellent yields, and high atom-economy and low -factor.

Lupeol alters viability of SK-RC-45 (Renal cell carcinoma cell line) by modulating its mitochondrial dynamics.

Renal cell carcinoma (RCC) is the most common kidney cancer leading to 140,000 deaths per year. Among all RCCs 80% evolve from the epithelial proximal tubular cells within the kidney. There is a high tendency of developing chemoresistance and resistance to radiation therapy in most RCC patients.

Sopherone A and B: Two new biologically relevant dibenzo-α-pyrones from Cassia sophera.

Sopherone A (1) and B (2), two new biologically relevant dibenzo-α-pyrones, were isolated from the stems of Cassia sophera Linn. (Caesalpiniaceae). Their structures were elucidated by detailed analysis of their spectroscopic data, including 1D and 2D NMR.

Target prioritization of novel substituted 5-aryl-2-oxo-/thioxo-2,3-dihydro-1-benzo[6,7]chromeno[2,3-]pyrimidine-4,6,11(5)-triones as anticancer agents using approach.

Cancer is a multi-origin collection of diseases attributed by abnormal and uncontrolled cell growth spread from origin to other parts of body eventually leading to death. After decades of research, anticancer drug therapy is still very much limited to inhibiting growth and controlling the spread of tumour cells. Finding novel molecular targets and drug candidates using assimilation of experimental and computational approaches is among the recent strategies adopted by researchers to speed up the anticancer drug discovery process.

Highly functionalized piperidines: Free radical scavenging, anticancer activity, DNA interaction and correlation with biological activity.

Twenty-five piperidines were studied as potential radical scavengers and antitumor agents. Quantitative interaction of compounds with ctDNA using spectroscopic techniques was also evaluated. Our results demonstrate that the evaluated piperidines possesses different abilities to scavenge the radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) and the anion radical superoxide (O).

Catalyst-Free One-Pot Three-Component Synthesis of Diversely Substituted 5-Aryl-2-oxo-/thioxo-2,3-dihydro-1-benzo[6,7]chromeno[2,3-]pyrimidine-4,6,11(5)-triones Under Ambient Conditions.

A simple, catalyst-free, straightforward, and highly efficient one-pot synthesis of pharmaceutically interesting diverse kind of a new series of functionalized 5-aryl-2-oxo-/thioxo-2,3-dihydro-1-benzo[6,7]chromeno[2,3-]pyrimidine-4,6,11(5)-triones () and substituted 5,5'-(1,4-phenylene)bis(2-oxo-/thioxo-2,3-dihydro-1-benzo[6,7]chromeno[2,3-]pyrimidine-4,6,11(5)-trione) derivatives () has been developed based on a three-component reaction between barbituric acid/,-dimethylbarbituric acid/2-thiobarbituric acid (), aromatic aldehydes (), and 2-hydroxy-1,4-naphthoquinone () in aqueous ethanol at room temperature (25-30 °C). The salient features of this protocol are mild reaction conditions, use of no catalyst, no need of column chromatographic purification, excellent yields, high atom economy, eco-friendliness, easy isolation of products, and reusability of reaction media.

Selective Pro-Apoptotic Activity of Novel 3,3'-(Aryl/Alkyl-Methylene)Bis(2-Hydroxynaphthalene-1,4-Dione) Derivatives on Human Cancer Cells via the Induction Reactive Oxygen Species.

Selective induction of apoptosis in cancer cells barring the normal cells is considered as an effective strategy to combat cancer. In the present study, a series of twenty-two (22) synthetic 3,3'-(aryl/alkyl-methylene)bis(2-hydroxynaphthalene-1,4-dione) bis-lawsone derivatives were assayed for their pro-apoptotic activity in six different cell lines (five cancerous and one normal) using MTT assay. Out of these 22 test compounds, 1j was found to be the most effective in inducing apoptosis in human glioma cells (CCF-4) among the different cell lines used in the study.

One-pot green synthesis of biologically relevant novel spiro[indolin-2-one-3,4'-pyrano[2,3-c]pyrazoles] and studies on their spectral and X-ray crystallographic behaviors.

Syntheses via green route and single-crystal X-ray structural investigations have been carried out for three spiro[indolin-2-one-3,4'-pyrano[2,3-c]pyrazole] derivatives, 6'-amino-2-oxo-3'-propyl-2'H-spiro[indoline-3,4'-pyrano[2,3-c]pyrazole]-5'-carbonitrile dimethyl sulfoxide monosolvate (5a), 6'-amino-5-fluoro-2-oxo-3'-propyl-2'H-spiro[indoline-3,4'-pyrano[2,3-c]pyrazole]-5'-carbonitrile dimethyl sulfoxide monosolvate (5b) and methyl 6'-amino-5-cyano-1-methyl-2-oxo-3'-propyl-2'H-spiro[indoline-3,4'-pyrano[2,3-c]pyrazole]-3'-carboxylate 0.25 hydrate (5c), respectively. Compounds (5a) and (5b) crystallize in the triclinic space group P\bar 1, whereas compound (5c) crystallizes in the monoclinic space group C2/c.