Asymmetric C(sp)-H borylation: an update.

Chiral organoboronates have emerged as a key intermediate in the development of pharmaceuticals and materials science. Therefore, several attempts have been made to design various synthetic methods to easily furnish these compounds during the past few decades. , asymmetric catalysis has been increasing rapidly as a viable, practical and beneficial strategy for their preparation.

Organocatalytic Oxidative C-H Amination of Aldehyde Hydrazones with Azoles at Ambient Temperature.

An efficient, metal-free, and direct oxidative amination of aldehyde-derived hydrazones with azoles has been developed using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone as an organocatalyst at ambient temperature. This protocol provides a wide range of aminated hydrazone derivatives in a step and atom economical fashion. The reaction possibly follows a radical mechanism.

Primary stress response and biochemical profile of Labeo rohita (Hamilton, 1822) experimentally parasitized with Argulus bengalensis (Ramakrishna, 1951).

Argulosis is a major problem that causes huge economic loss in aquaculture. In a microcosm, an infested condition was developed upon Labeo rohita with 100 ± 10 adult morphs of Argulus bengalensis per fish. Primary stress response and biochemical profiles of the host were evaluated to underscore the pathogenicity of the parasites.

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.

Visible light-induced functionalization of indazole and pyrazole: a recent update.

Indazole and pyrazole are renowned as a prodigious class of heterocycles having versatile uses in medicinal as well as industrial chemistry. Considering sustainable approaches, recently, photocatalysis has become an indispensable tool in organic chemistry due to its application for the activation of small molecules and the use of a clean energy source. In this review, we have highlighted the use of metal-based photocatalysts, organic photoredox catalysts, energy transfer photocatalysts and electron-donor-acceptor complexes in the functionalization of indazole and pyrazole.

Synthetic approaches to 1,2,4-triazolo[5,1-][1,2,4]triazin-7-ones as basic heterocyclic structures of the antiviral drug Riamilovir ("Triazavirin®") active against SARS-CoV-2 (COVID-19).

Fragments of 1,2,4-triazolo[5,1-][1,2,4]triazin-7-one are found in many compounds with various types of biological activities, including the antiviral drug Riamilovir (Triazavirin®), which shows activity against SARS-CoV-2 (COVID-19). Therefore, the development of convenient methods for the synthesis of new derivatives of 1,2,4-triazolo[5,1-][1,2,4]triazin-7-one is always in demand. This review systematizes the information on the most common synthetic methods for constructing the 1,2,4-triazolo[5,1-][1,2,4]triazin-7-one heterocyclic system.

Comprehensive characterization and molecular insights into the salt tolerance of a Cu, Zn-superoxide dismutase from an Indian Mangrove, Avicennia marina.

Superoxide dismutases are important group of antioxidant metallozyme and play important role in ROS homeostasis in salinity stress. The present study reports the biochemical properties of a salt-tolerant Cu, Zn-superoxide from Avicennia marina (Am_SOD). Am_SOD was purified from the leaf and identified by mass-spectrometry.

Modulation of Phototropin Signalosome with Artificial Illumination Holds Great Potential in the Development of Climate-Smart Crops.

Changes in environmental conditions like temperature and light critically influence crop production. To deal with these changes, plants possess various photoreceptors such as Phototropin (PHOT), Phytochrome (PHY), Cryptochrome (CRY), and UVR8 that work synergistically as sensor and stress sensing receptors to different external cues. PHOTs are capable of regulating several functions like growth and development, chloroplast relocation, thermomorphogenesis, metabolite accumulation, stomatal opening, and phototropism in plants.

Synthesis of Unsymmetrical Biheteroarenes via Dehydrogenative and Decarboxylative Coupling: a Decade Update.

The design and development of robust and efficient methods for installing one heterocycle with another is endowed as a ubiquitous and powerful synthetic strategy to access complex organic biheterocycles in recent days due to their pervasive applications in medicinal as well as material chemistry. This perspective presents an overview on the recent findings and developments for the synthesis of unsymmetrical biheteroarenes via dehydrogenative and decarboxylative couplings with literature coverage mainly extending from 2011 to 2021. For simplification of the readers, the article has been subcategorized based on the catalysts used in the reactions.

Remote difunctionalization of 2-indazoles using Koser's reagents.

A new, efficient, and metal-free protocol has been developed for remote difunctionalization of unreactive C-H bonds at the benzene core of 2-indazole by employing Koser's reagents, which act as both sulfonyloxylating and iodinating agents under ambient air. The present methodology represents facile access to C-4-sulfonyloxylated and C-7-iodinated 2-indazole derivatives with high regioselectivity, wide functional group tolerance, and broad substrate scope in good to excellent yields. The formed 4,7 disubstituted 2-indazoles are the precursors of various C-4,7-functionalized 2-indazoles through simple transformations.

Ortho C-H Functionalization of 2-Arylimidazo[1,2-a]pyridines.

C-H activation and functionalization is quite promising in recent days as the strategy offers a go-to general method for different bond formations and hence grants synthetic versatility. At the same time, imidazopyridine, a fused bicycle of imidazole moiety with pyridine ring, has a profound impact due to its ubiquitous and prodigious application in medicinal as well as material chemistry. The presence of N-1 atom in 2-arylImidazo[1,2-a]pyridine facilitates the coordination with metal catalysts leading to the formation of ortho-substituted products.

Fetuin-A regulates adipose tissue macrophage content and activation in insulin resistant mice through MCP-1 and iNOS: involvement of IFNγ-JAK2-STAT1 pathway.

In the context of obesity-induced adipose tissue (AT) inflammation, migration of macrophages and their polarization from predominantly anti-inflammatory to proinflammatory subtype is considered a pivotal event in the loss of adipose insulin sensitivity. Two major chemoattractants, monocyte chemoattractant protein-1 (MCP-1) and Fetuin-A (FetA), have been reported to stimulate macrophage migration into inflamed AT instigating inflammation. Moreover, FetA could notably modulate macrophage polarization, yet the mechanism(s) is unknown.

One-Pot Construction of Indolo[2,3-]quinoxalines through Ruthenium-Catalyzed C-H Bond Functionalization of 2-Arylquinoxalines with Sulfonyl Azides.

The synthesis of N-substituted indolo[2,3-]quinoxalines has been developed through a Ru(II)-catalyzed C-H functionalization of 2-arylquinoxalines with sulfonyl azides and further oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone in one pot. This double C-N bond formation strategy provides a new efficient route for the preparation of a series of biologically relevant 6-indolo[2,3-]quinoxaline derivatives in up to 94% yield, suggesting a broad substrate scope applicability. The preliminary mechanistic studies reveal that the sequential C-N bond formations proceed through the formation of a five-membered ruthenacyclic intermediate in the first step and a radical mechanism in the second step.

Mycosporine-alanine, an oxo-mycosporine, protect Hassallia byssoidea from high UV and solar irradiation on the stone monument of Konark.

Mycosporine-like amino acids (MAAs) are small natural molecules having potent UV-absorbing and antioxidant properties. Hassallia byssoidea is one dominant cyanobacterium found all over the Konark stone monument, a UNESCO World Heritage site. We characterized mycosporine-alanine for the first time from H.

Three-Component Carbosilylation of Alkenes by Merging Iron and Visible-Light Photocatalysis.

A mild, efficient, and one-pot protocol for three-component carbosilylation of alkenes with imidazoheterocycle and silanes has been developed by merging iron(II) and visible-light photocatalysis. This C-C and C-Si bond-forming method provides functionalized organosilicon derivatives having imidazoheterocycles moieties in good yields. The reaction possibly proceeds through a radical pathway.

Fluorination of 2-Indazoles Using -Fluorobenzenesulfonimide.

An efficient, simple, and metal-free fluorination of 2-indazoles has been developed using -fluorobenzenesulfonimide (NFSI) in water under ambient air. This transformation provides direct access to fluorinated indazole derivatives with broad functionalities in satisfactory yields. The experimental results suggest a radical mechanistic pathway of this protocol.

Potassium Persulfate Mediated Chemodivergent C-3 Functionalization of 2-Indazoles with DMSO as C Source.

A facile, efficient, and transition-metal-free chemodivergent C-3 functionalization of 2-indazoles was developed under aerobic conditions using carboxylic acid and DMSO as the combined source of the carboxylic acid ester group and DMSO as the formylating agent. A series of formylated indazoles and carboxylic acid esters of indazole derivatives were produced in moderate to excellent yields. The mechanistic studies suggest that the reactions probably proceed through a radical pathway.

Advances in targeting the WNT/β-catenin signaling pathway in cancer.

WNT/β-catenin signaling orchestrates various physiological processes, including embryonic development, growth, tissue homeostasis, and regeneration. Abnormal WNT/β-catenin signaling is associated with various cancers and its inhibition has shown effective antitumor responses. In this review, we discuss the pathway, potential targets for the development of WNT/β-catenin inhibitors, available inhibitors, and their specific molecular interactions with the target proteins.

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.

Light-induced borylation: developments and mechanistic insights.

Organoboron compounds are very important derivatives because of their profound impacts on medicinal, biological as well as industrial applications. The development of several novel borylation methodologies has achieved momentous interest among synthetic chemists. In this scenario, eco-friendly light-induced borylation is progressively becoming one of the best synthetic tools in recent days to prepare organoboronic ester and acid derivatives based on green chemistry rules.

Entropy generation in nanofluid flow due to double diffusive MHD mixed convection.

This work is concerned with the numerical study of laminar, steady MHD mixed convection flow, and entropy generation analysis of -water nanofluid flowing in a lid-driven trapezoidal enclosure. The aspect ratio of the cavity is taken very small. The cavity is differentially heated to study the fluid flow, heat, and mass transfer rate.

Visible-light-induced silylation: an update.

Visible-light-driven functionalization of various organic systems has proved to be extremely successful and reached an impressive level of sophistication as well as efficiency in the last two decades. At the same time, organosilicon compounds are significant due to their promising applications in therapeutic agents, drug delivery, building blocks and so on. More interestingly, they are cheap, operationally simple, highly stable, less toxic and easy to handle.

Low-cost technology for COVID-19 infection detection through smell loss test: An overview.

Corona virus (COVID-19) infection has been growing as a biggest threat to human society. World Health Organization (WHO) has already declared it as a pandemic for the whole world, with nearly six million positive cases. Highly contagious nature of the virus has challenged the medical facilities of all the developed and developing country health system.

A practicable synthesis of 2,3-disubstituted 1,4-dioxanes bearing a carbonyl functionality from α,β-unsaturated ketones using the Williamson strategy.

We have observed that a reagent combination of NaIO and NHOH·HCl reacts with α,β-unsaturated ketones followed by the nucleophile ethylene glycol allowing the synthesis of 2,3-disubstituted 1,4-dioxanes using cesium carbonate as a base under Williamson ether synthesis. This reaction is useful for the synthesis of functionalized 1,4-dioxane having a carbonyl functionality. A variety of 2,3-disubstituted 1,4-dioxanes have been synthesized using these reaction conditions.