Harnessing benzotriazole as a sustainable ligand in metal-catalyzed coupling reactions.

Coupling reactions play a crucial role in drug development enabling the rapid expansion of structure-activity relationships (SARs) during drug discovery programs to identify a clinical candidate and simplify subsequent drug development processes. In particular, their relevance in clinical medicine and drug discovery has increased significantly in the last two decades. To facilitate these metal-catalyzed coupling reactions, suitably designed ligands are necessary and from the industrial point of view, sustainable and cost-effective ligands are of current need. Benzotriazole, a non-toxic, thermally stable, and inexpensive bidentate ligand, exhibits strong electron donating and electron accepting properties, along with excellent solubility in various organic solvents. It has been extensively explored as a synthetic auxiliary in the past; in recent years, benzotriazole and its derivatives have been used as ligands in metal-catalyzed coupling reactions. The facile construction of carbon-carbon and carbon-heteroatom bonds in the presence of versatile benzotriazole ligands makes it an indispensable ligand for catalytic transformations. The present feature article mainly emphasizes the advances in the utilization of benzotriazole as a ligand in a diverse range of C-C, C-N, C-O, and C-S coupling reactions.

Advancement in Synthetic Strategies of Phosphorus Heterocycles: Recent Progress from Synthesis to Emerging Class of Optoelectronic Materials.

Organophosphorus heterocycles have long been acknowledged for their significant potential across diverse fields, including catalysis, material science, and drug development. Incorporating phosphorus functionalities into organic compounds offers a means to effectively tailor their medicinal properties, augment biological responses, and enhance selectivity and bioavailability. The distinctive physical and photoelectric characteristics of phosphorus-containing conjugated compounds have garnered considerable interest as promising materials for organic optoelectronics. These compounds find extensive utility in various applications such as light-emitting diodes, photovoltaic cells, phosphole-based fluorophores, and semiconductors.

Transition-metal free, radical oxidation of 1,6-enyne cyclopropanation: synthesis of aza-bicyclo[4.1.0]heptane derivatives.

A straightforward transition-metal-free sustainable methodology for oxidative cyclopropanation of aza-1,6-enynes has been devised, enabling the synthesis of valuable, functionalized azabicyclo[4.1.0]heptane-2,4,5-triones, via four bond formation in a single step under mild conditions. Control experiments and real-time mass data monitoring using online ESI-MS spectroscopy support the pathway proposed for this reaction. The synthesized products have been utilized in diverse product transformations. Key advantages of this reaction include its operational ease, transition metal-free nature, rapid completion, and compatibility with a wide range of functional groups and substrates.

Effect of Addition of Mango Seed Extract on Storage Stability of Chevon Meatballs at Refrigeration Temperature.

In this study, the addition of mango seed extract (MSE) in goat meatballs was assessed. The efficacy of three different levels of MSE extract, namely T1 = (2.5 mL/100 g of meat emulsion v/w), T2 = (5.0 mL/100 g of meat emulsion v/w), T3 = (7.5 mL/100 g of meat emulsion v/w), and T0 (control without mango seed extract), was conducted for evaluation of changes in water activity (aW), pH, total phenolic compounds, DPPH, peroxide value, TBARS, microbial quality, and sensory attributes of the goat meatballs stored at refrigerated temperature (4 ± 1 °C). Incorporation of the mango seed extract T3 (7.5 mL/100 g) showed that it can potentially better maintain change in pH and water activity. Total phenolic and DPPH activity decreased significantly (P0.05) among all samples throughout storage; however, the highest value was noted for T3 among all samples. The MSE-added goat meatballs (T3) group had lower significant (p < 0.05) peroxide values than the other samples. The T3 sample added with MSE exhibited significant (p < 0.05) lower TBRAS values as compared to other treatments. Comparatively lower microbial proliferation and better sensory attributes were maintained among the treated groups during the entire storage time. The results show that the inclusion of MSE extract T3 (7.5 mL/100 g) is a promising natural antioxidant that can maintain a better quality of goat meatballs at refrigerated temperature (4 ± 1 °C) under aerobic packaging conditions.

o-Alkynylaryl 2-Cyanoacrylates: A Synthon for the Construction of Diverse Isoquinolones/Napthyridinones.

o-Alkynylaryl 2-cyanoacrylates have been disclosed as a new synthon for the regioselective synthesis of isoquinolones and naphthyridinones under mild reaction conditions. The attractive feature of this investigation includes carbon-carbon double bond cleavage under metal-free conditions by an intramolecular SN2 reaction. Incorporating two distinct C-I bonds in the resulting products provides facile opportunity for structural elaboration. The viability of the present protocol was unveiled by postfunctionalization with drug analogues and gram-scale synthesis.

Base-mediated ynone-isocyanide [3+2] cycloaddition: a general method to 2,3,4-tri-substituted 1-H-pyrroles and bis-pyrroles.

A transition-metal-free and base-promoted one-pot synthesis of 2,3,4-trisubstituted 1-H-pyrroles has been developed. The reaction occurs through the [3+2] cycloaddition of differently functionalized ynones and isocyanides. The reaction's advantageous features are operational simplicity, atom economy, and functional group tolerance with broad substrate scope. In addition, 1,3-bis-pyrrole formation and gram-scale synthesis were also achieved. Furthermore, the synthetic utility of the products was also investigated via isocyanide insertion and pyrrole-triazole hybrid formation in good yield.

Stereoselective synthesis of difunctionalized succinimides from aza-1,6-enynes by radical cascade reaction.

A transition-metal-free one-pot synthesis of di-functionalized succinimides by radical cascade seleno/thiosulfonation of aza-1,6-enynes in an atom economical manner has been developed. The developed method allows the synthesis of highly decorated succinimides under mild reaction conditions with excellent stereoselectivity. The proposed radical pathway for the reaction is well supported by the control experiments. The reaction's advantageous features are operational simplicity, atom economy, and functional group tolerance with broad substrate scope.

A unified approach to benzo[c]phenanthridines via the cascade dual-annulation/formylation of 2-alkynyl/alkenylbenzonitriles.

A base-mediated versatile cascade dual-annulation and formylation of 2-alkenyl/alkynylbenzonitriles with 2-methylbenzonitriles has been established for the construction of four different classes of amino and amido substituted benzo[c]phenanthridines and benzo[c]phenanthrolines. The synthesized molecules could be of utmost relevance in pharmaceuticals. The transformation uses the solvent DMF as the formyl source for synthesis of the amido-substituted scaffolds. This transition-metal-free unique strategy enables the formation of multiple C-C and C-N bonds in one pot at room temperature.

Copper iodide nanoparticles (CuI NPs): an efficient catalyst for the synthesis of alkynyl esters.

An environmentally benign protocol for the synthesis of alkynyl esters, by the cross-coupling of diazoacetate with various substituted alkynes under neat reaction conditions, has been described. Copper iodide nanoparticles (CuI NPs) were found to promote the Sonogashira-type coupling to afford the corresponding alkynyl esters in good yields. The CuI nanoparticles were characterized by PXRD, FESEM, EDAX, and Raman techniques. The developed methodology has several advantages such as a broad substrate scope, less reaction time, atom economy, avoidance of an additive/base/solvent, and enhanced values of green chemistry. The catalyst was recycled up to threefold without the loss of its catalytic activity.

Unveiling the Three-Component Phosphonylation on Alkynylaldehydes: Toolbox toward Fluorescent Molecules.

A regioselective tandem approach for annulated napthyridines/isoquinolines embedded with the phosphine oxide group under mild reaction conditions has been achieved in good to excellent yields. The designed strategy involves the triflate-induced formation of new C sp3-P and C sp2-N bond formation in one pot. This protocol was also well tolerated for the construction of densely functionalized organo-phosphorylated chromenes in good yields. Further, phosphino-derived sulfamethazine and sulfamethoxazole drugs were also successfully synthesized in good yields. The mechanistic studies revealed that the ionic pathway and the formation of regioselective 6-endo dig cyclized products were confirmed through X-ray crystallographic studies. Interestingly, photophysical studies of selectivity selected compounds revealed their stimulating fluorescence properties.

Effect of Turmeric and Aloe Vera Extract on Shelf-Life of Goat and Buffalo Admixture Milk Paneer during Refrigeration Storage.

The present study was undertaken to evaluate efficacy of turmeric and aloe vera extract in extending shelf life of goat milk paneer. The paneer was made by admixing goat milk and buffalo milk in the ratio of 60:40 so as to achieve a standard fat 4.5%. The treatment group, T1, was made by adding 5 mL/100 mL (v/v) of turmeric extract in heated milk before coagulation. Similarly, 5 mL/100 mL (v/v) aloe vera extract was added to heated milk for group T2 while T3 was prepared by adding both turmeric extract 5 mL/100 mL (v/v) and aloe vera extract 5 mL/100 mL (v/v), and the control was made without any additive. The extracts before incorporation were assessed for their antioxidant and antimicrobial potential by analysing total phenolic content, ABTS and DPPH percent inhibition and zone of inhibition. The developed paneer samples were evaluated for physico-chemical, oxidative and microbiological changes, and sensory attributes during storage at refrigeration temperature for ten days. The results revealed that paneer prepared with addition of extracts significantly (p < 0.05) suppressed physico-chemical deterioration. Significantly (p < 0.05) lower peroxide value, TBARS, FFA and microbial counts were noticed in T3 than T1, T2 and the control. The sensory attributes were also better (p < 0.05) maintained in T3 during storage. The results concluded that the combination of turmeric and aloe vera extract significantly improves the shelf life of paneer under refrigeration storage and these might be used as phyto-preservatives in paneer.

Recent applications of nanoparticles in organic transformations.

A variation in the size of metal nanoparticles leads to a difference in their properties. As the size of metal nanoparticles decreases, the surface area increases which leads to an increase in the reactivity of metal nanoparticles. Metals like Au, Ag, Pd, and Pt have interesting properties when used in nanometric dimensions. They function efficiently in significant industrial processes as electrocatalysts and photocatalysts in various organic reactions. Recently, the green biosynthesis of nanoparticles has attracted the attention of researchers. With environmental pollution rising over the past few decades, metal nanoparticle catalysts could be the key to subdue the toxic effects. Being versatile, they can be used to degrade pollutants, develop solar cells, convert toxic nitroaromatic compounds, significantly reduce CO2 emissions per unit of energy, and many more. Owing to their unique properties, nanoparticles have wide applications in biomedicine, for example, gold cages are promising agents for cancer diagnosis and therapy. Transition metal-oxide nanoparticles have been considered one of the best supercapacitor electrodes with high electrochemical performance. In this review, we have summarised fundamental concepts of metal nanoparticles over the last decade's main emphasis from 2010 to 2021. It focuses on the exceptional use of these nanocatalysts in various organic reactions. Additionally, we have also discussed the utility of these reactions and their crucial role in solving the problems of today. Through this article, we hope to provide the necessary framework needed to further advance the applications of metal nanoparticles as catalysts.

Transition-metal-free regioselective hydroamination of styrenes with amino-heteroarenes.

The base-mediated anti-Markovnikov hydroamination of functionally varied styrenes with amino-substituted pyridine, quinoline, pyrimidine, pyrazine, and phenanthridine with excellent regioselectivity has been described. Double hydroamination was observed chemoselectively on the secondary amine, leaving the primary amine intact. Experimental evidence suggests that the proposed reaction involves the nucleophilic addition of the aminopyridyl radical onto vinyl arenes via a single electron transfer.

Expedient Access to Polyaromatic Biaryls by Unconventional Ag-Catalyzed Cycloaromatization of Alkynylthiophenes and Au-Catalyzed Double C-H Activation.

An unconventional approach for the regioselective synthesis of polyaromatic biaryls via site-selective Ag-catalyzed twofold electrophilic cycloisomerization followed by Au-catalyzed double C-H activation is described. The developed process allows the synthesis of highly decorated biaryls with excellent regioselectivity. As revealed by DFT computations, the reaction represents a rare example of C1-C5 endo-exo and C1-C6 endo-endo cycloaromatization. The formation of the 6-membered ring is predicted to be the fruit of an uncommon SEAr on a vinyl carbocation.

Visible-Light-Accelerated Copper-Catalyzed [3 + 2] Cycloaddition of N-Tosylcyclopropylamines with Alkynes/Alkenes.

Copper-catalyzed [3 + 2] cycloadditions of N-tosylcyclopropylamine with alkynes and alkenes have been accomplished under visible light irradiation. The developed approach is compatible with a range of functionalities and allows the synthesis of diversified aminated cyclopentene and cyclopentane derivatives being relevant for drug synthesis. The protocol is operationally simple and economically affordable as it does not require any ligand, base, or additives. As the key step, the one-electron oxidation of the N-tosyl moiety by visible light-induced homolysis of a transient Cu(II)-tosylamide complex is proposed, providing a facile entry for N-centered radicals.

Assessment of quality attributes of porcine blood and liver hydrolysates incorporated pork loaves stored under aerobic and modified atmospheric packaging.

Lipid oxidation and microbial proliferations were studied in pork loaves prepared with incorporation of blood and liver protein hydrolysates stored in aerobic and MAP packaging for 28 and 42 days at 4 ± 1 ºC. In in-vitro trials selected levels i.e. blood hydrolysate (T1 and T3-600 mg/g), and liver hydrolysate (T2 and T4-600 mg/g), control without hydrolysate (C1-00 and C2-00 mg/g) w/w of emulsion, were added into pork loaves and packaged under aerobic (C1, T1 and T2) and MAP (C2, T3 and T4) condition. Physico-chemicals as pH, water activity, titratable acidity, lipid-oxidations, color profile, textural indices, microbial qualities and sensorial properties were analyzed. Significant (p < 0.05) lower lipid oxidation, microbial proliferations and decrease in sensory attributes were seen for tested groups and MAP than aerobic packaging. It can be concluded that pork loaves containing porcine blood and liver hydrolysates can be successfully stored upto 28th days in aerobically packed and 42 days in MAP condition at refrigerated storage with acceptable physico-chemical, oxidative stability, microbiological and sensory quality. Whereas, pork loves prepared with blood hydrolysate (T3-600 mg/g), packaged under MAP condition were superior for all studied attributes than other groups. Blood and liver hydrolysate might be used as an alternative to synthetic preservative for meat preservation.

Technological interventions in improving the functionality of proteins during processing of meat analogs.

Meat analogs have opened a new horizon of opportunities for developing a sustainable alternative for meat and meat products. Proteins are an integral part of meat analogs and their functionalities have been extensively studied to mimic meat-like appearance and texture. Proteins have a vital role in imparting texture, nutritive value, and organoleptic attributes to meat analogs. Processing of suitable proteins from vegetable, mycoproteins, algal, and single-cell protein sources remains a challenge and several technological interventions ranging from the isolation of proteins to the processing of products are required. The present paper reviews and discusses in detail various proteins (soy proteins, wheat gluten, zein, algal proteins, mycoproteins, pulses, potato, oilseeds, pseudo-cereals, and grass) and their suitability for meat analog production. The review also discusses other associated aspects such as processing interventions that can be adapted to improve the functional and textural attributes of proteins in the processing of meat analogs (extrusion, spinning, Couette shear cell, additive manufacturing/3D printing, and freeze structuring). '.

Tandem 6π-Azatriene Electrocyclization of Fused Amino-cyclopentenones: Synthesis of Functionalized Pyrrolo- and Indolo-quinoxalines.

A tandem 6π-azacyclization approach for the synthesis of diversified pyrrolo/indolo[1,2-a]quinoxalines from amino-cyclopentenones has been developed. The reaction proceeds through a trifluoroacetic-acid-mediated 6π-electrocyclization and concomitant opening of the cyclopentenone ring. The advantageous features of the developed chemistry include transition-metal-free conditions, operational simplicity, and a broad substrate scope. Further X-ray crystallographic studies confirm the assigned structures of the fused heterocycles.

Optimization of processing conditions for development of chicken meat incorporated whole wheat bread.

Present study was conducted to explore the incorporation of high level of chicken meat powder for developing protein enriched whole wheat bread. The aim was to optimise meat level and processing conditions for development of chicken meat bread. Box-Beheken design of response surface methodology was used for optimising the processing conditions of chicken meat incorporated whole wheat bread as processing conditions strongly influence the product characteristics. Meat level (30-35%), proofing time (60-120 min) and cooking time (10-12 min) were contemplated as constrains or variable factors for their effect on responses such as baking yield, moisture, protein, fat, ash, redness and yellowness value, flavour, porosity and overall acceptability which are essential for product acceptability and marketability, while the cooking temperature was kept constant at 220 °C. The responses were assessed by evaluating the physicochemical, proximate, colour units and sensory evaluation. A high coefficient of regression > 0.90 was obtained for all the responses indicating the fit of model. The desirability achieved for these responses was 0.841 for 31.497% meat level with proofing time 107.17 min and baking time of 12.74 min. The study concluded with development of chicken meat bread having high protein content with optimised processing conditions of proofing and cooking time.

Diacetylene-Based Colorimetric Radiation Sensors for the Detection and Measurement of γ Radiation during Blood Irradiation.

Blood and its cellular components are irradiated by ionizing radiation before transfusion to prevent the proliferation of viable T lymphocytes which cause transfusion associated-graft versus host disease. The immunodeficient patients undergoing chemotherapy for various malignancies are at risk of this disease. The international guidelines for blood transfusion recommend a minimum radiation exposure of 25 Gray (Gy) to the midplane of the blood bag, while a minimum dose of 15 Gy and a maximum dose of 50 Gy should be given to each portion of the blood bag. Therefore, precise dosimetry of the blood irradiator is essential to ensure the adequate irradiation of the blood components. The paper presents the fabrication of diacetylene-based colorimetric film dosimeters for the verification of irradiated doses. The diacetylene analogues are synthesized by tailoring them with different amide-based headgroups followed by their coating to develop colorimetric film dosimeters. Among all the synthesized diacetylene analogues, aminofluorene-substituted diacetylene exhibits the most significant color transition from white to blue color at a minimum γ radiation dose of 5 Gy. The quantitative study of color change is performed by the digitization of the scanned images of film dosimeters. The digital image processing of the developed film dosimeters facilitates rapid dose measurement which enables their facile implementation and promising application in routine blood irradiator dosimetry.