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Carbazoles are nitrogen-containing aromatic heterocycles, having widespread applications in the field of photovoltaics. Carbazole-based photosensitizers have tunable features for absorption on semi-conductor (tellurium dioxide or zinc oxide) layers to create sufficient push-pull force in the conversion of sunlight into electrical energy, thus presenting as promising heterocyclic donor candidates to be used in dye-sensitized solar cells. For the synthesis of these dyes, various structural designs are available, namely, D-A, D-π-A, D-D-π-A, D-A-π-A, A-π-D-π-A-π-A, and D2-π-A that all involve incorporating carbazole as a donor (D), along with spacer (π-extender) moieties, such as thiophene, phenol, ethynylene, nitromethane, azine, thiadiazole, or acetonitrile. Additionally, acceptors (A) employed in the designs include cyanoacrylic acids, carboxylic acids, malononitrile, rhodanine-3-acetic acid, 4-aminobenzoic acid, or 4-amino salicylic acid. This comprehensive review explores the synthesis and photovoltaic performances of numerous carbazole-based photosensitizers tailored for dye-sensitized solar cells, covering the period of 2019-2023., Competing Interests: Declarations. Competing Interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

A novel series of substituted benzofuran-tethered triazolylcarbazoles was synthesized in good to high yields (65-89%) via S -alkylation of benzofuran-based triazoles with 2-bromo- N -(9-ethyl-9 H -carbazol-3-yl)acetamide. The inhibitory potency of the synthesized compounds against SARS-CoV-2 was evaluated by enacting molecular docking against its three pivotal proteins, namely, M pro (main protease; PDB ID: 6LU7), the spike glycoprotein (PDB ID: 6WPT), and RdRp (RNA-dependent RNA polymerase; PDB ID: 6M71). The docking results indicated strong binding affinities between SARS-CoV-2 proteins and the synthesized compounds, which were thereby expected to obstruct the function of SARS proteins. Among the synthesized derivatives, the compounds 9e , 9h , 9i , and 9j exposited the best binding scores of -8.77, -8.76, -8.87, and -8.85 Kcal/mol against M pro , respectively, -6.69, -6.54, -6.44, and -6.56 Kcal/mol against the spike glycoprotein, respectively, and -7.61, -8.10, -8.01, and -7.54 Kcal/mol against RdRp, respectively. Furthermore, the binding scores of 9b (-8.83 Kcal/mol) and 9c (-8.92 Kcal/mol) against 6LU7 are worth mentioning. Regarding the spike glycoprotein, 9b , 9d , and 9f expressed high binding energies of -6.43, -6.38, and -6.41 Kcal/mol, accordingly. Correspondingly, the binding affinity of 9g (-7.62 Kcal/mol) against RdRp is also noteworthy. Furthermore, the potent compounds were also subjected to ADMET analysis to evaluate their pharmacokinetic properties, suggesting that the compounds 9e , 9h , 9i , and 9j exhibited comparable values. These potent compounds may be selected as inhibitory agents and provide a pertinent context for further investigations.

The development of novel and efficient tyrosinase inhibitors is a critical necessity of agricultural, cosmetic and medicinal chemistry. Bearing in mind the therapeutical potential of naphthofuran-containing organic compounds, we carried out the CTAB-catalyzed ultrasound-assisted synthesis of a library of novel naphthofuran-triazole joined N -aryl/alkyl acetamides 20(a-j) in 74-92% yield, which were further assessed for their tyrosinase inhibitory potential by taking kojic acid and ascorbic acid as standard inhibitors. The tyrosinase inhibitory assay demonstrated the promising tyrosinase inhibiting tendency of all prepared derivatives 20(a-h) as they all were found to be more efficient in comparison to the standard kojic acid. Similarly, most of the derivatives also exhibited tyrosinase inhibition potency in juxtaposition to ascorbic acid. More specifically, among the catalog of compounds, 20f and 20i exhibited potent inhibition results with IC 50 = 0.51 ± 0.12 and 1.99 ± 0.07, respectively. Overall, 20f was shown to be the most efficacious tyrosinase inhibitor, owing to the presence of an electronegative group, i.e. , 2-chloro substitution on the phenyl ring. The tyrosinase inhibition activity results of 20f and 20i were further supplemented with molecular docking analysis to validate experimental studies. In silico modelling findings revealed their significant interactions with the tyrosinase protein (PDB ID: 5OAE), thereby illustrating the efficient docking score of -7.10 kcal mol -1 and -6.95 kcal mol -1 in comparison to kojic acid (-5.03 kcal mol -1 )., Competing Interests: The authors have no conflict of interest for this research work., (This journal is © The Royal Society of Chemistry.)

The Barbier reaction is significantly referred to as one of the efficient carbon-carbon bond forming reactions which involves the treatment of haloalkanes and carbonyl compounds by utilizing the catalytic role of a diverse range of metals and metalloids. The Barbier reaction is tolerant to a variety of functional groups, allowing a broad substrate scope with the employment of lanthanides, transition metals, amphoteric elements or alkaline earth metals. This reaction is also water-resistant, thereby overcoming the challenges posed by moisture sensitive organometallic species involving C-C bond formation reactions. The Barbier reaction has significantly found its applicability towards the synthesis of intricate and naturally occurring organic compounds. Our review provides an outlook on the synthetic applications of the Barbier reaction and its variants to accomplish the preparation of several natural products, reported since 2020., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Baeyer-Villiger oxidation is a well-known reaction utilized for the synthesis of lactones and ester functionalities from ketones. Chiral lactones can be synthesized from chiral or racemic ketones by employing asymmetric Baeyer-Villiger oxidation. These lactones act as key intermediates in the synthesis of most of the biologically active natural products, their analogues, and derivatives. Various monooxygenases and oxidizing agents facilitate BV oxidation, providing a broad range of synthetic applications in organic chemistry. The variety of enzymatic and chemoselective Baeyer-Villiger oxidations and their substantial role in the synthesis of natural products i.e. , alkaloids, polyketides, fatty acids, terpenoids, etc. (reported since 2018) have been summarized in this review article., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In this study, a series of 1,2,4-triazole-tethered β-hydroxy sulfide scaffolds 11a-h was synthesized in good to remarkable yields (69-90%) through the thiolysis of oxiranes by the thiols in aqueous basic catalytic conditions. The synthesized 1,2,4-triazole-tethered β-hydroxy sulfides were screened against bacterial tyrosinase enzyme, and Gram-positive and Gram-negative bacterial cultures i.e. , ( S. aureus ) Staphylococcus aureus & ( E. coli ) Escherichia coli . Among the synthesized derivatives, the molecules 11a (IC 50 = 7.67 ± 1.00 μM), 11c (IC 50 = 4.52 ± 0.09 μM), 11d (IC 50 = 6.60 ± 1.25 μM), and 11f (IC 50 = 5.93 ± 0.50 μM) displayed the better tyrosinase inhibitory activity in comparison to reference drugs ascorbic acid (IC 50 = 11.5 ± 1.00 μM) and kojic acid (IC 50 = 30.34 ± 0.75 μM). The molecule benzofuran-triazol-propan-2-ol 11c proved to be the most potent bacterial tyrosinase inhibitory agent with a minimum IC 50 of 4.52 ± 0.09 μM, as compared to other synthesized counterparts and both standards (kojic acid and ascorbic acid). The compound diphenyl-triazol-propan-2-ol 11a and benzofuran-triazole-propan-2-ol 11c showed comparable anti-bacterial chemotherapeutic efficacy with minimum inhibitory concentrations (MIC = 2.0 ± 2.25 mg mL -1 and 2.5 ± 0.00 mg mL -1 , respectively) against S. aureus bacterial strain in comparison with standard antibiotic penicillin (MIC = 2.2 ± 1.15 mg mL -1 ). Furthermore, among the synthesized derivatives, only compound 11c demonstrated better anti-bacterial activity (MIC = 10 ± 0.40 mg mL -1 ) against E . coli , which was slightly less than the standard antibiotic i.e. , penicillin (MIC = 2.4 ± 1.00 mg mL -1 ). The compound 11c demonstrated a better binding score (-7.08 kcal mol -1 ) than ascorbic acid (-5.59 kcal mol -1 ) and kojic acid (-5.78 kcal mol -1 ). Molecular docking studies also validate the in vitro anti-tyrosinase assay results; therefore, the molecule 11c can be the lead bacterial tyrosinase inhibitor as well as the antibacterial agent against both types of bacterial strains after suitable structural modifications., Competing Interests: Authors have no conflict of interest for this research work., (This journal is © The Royal Society of Chemistry.)

The synthesis of dihydrobenzofuran scaffolds bears pivotal significance in the field of medicinal chemistry and organic synthesis. These heterocyclic scaffolds hold immense prospects owing to their significant pharmaceutical applications as they are extensively employed as essential precursors for constructing complex organic frameworks. Their versatility and importance make them an interesting subject of study for researchers in the scientific community. While exploring their synthesis, researchers have unveiled various novel and efficient pathways for assembling the dihydrobenzofuran core. In the wake of extensive data being continuously reported each year, we have outlined the recent updates (post 2020) on novel methodological accomplishments employing the efficient catalytic role of several transition metals to forge dihydrobenzofuran functionalities., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Epoxides are oxygen containing heterocycles which are significantly employed as crucial intermediates in various organic transformations. They are considered highly reactive three-membered heterocycles due to ring strain and they undergo epoxide ring opening reactions with diverse range of nucleophiles. Epoxide ring-opening reactions have gained prominence as flexible and effective means to obtain various functionalized molecules. These reactions have garnered substantial attention in organic synthesis, driven by the need to comprehend the synthesis of biologically and structurally important organic compounds. They have also found applications in the synthesis of complex natural products. In this review article, we have summarized the implementation of epoxide ring opening reactions in the synthesis of alkaloids and terpenoids based natural products reported within the last decade (2014-2023)., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Zinc (Zn) is a crucial element with remarkable significance in organic transformations. The profusion of harmless zinc salts in the Earth's outer layer qualifies zinc as a noteworthy contender for inexpensive and eco-friendly reagents and catalysts. Recently, widely recognized uses of organo-Zn compounds in the field of organic synthesis have undergone extensive expansion toward asymmetric transformations. The ProPhenol ligand, a member of the chiral nitrogenous-crown family, exhibits the spontaneous formation of a dual-metal complex when reacted with alkyl metal (R-M) reagents, e.g., ZnEt 2 . The afforded Zn complex possesses two active sites, one Lewis acid and the other Brønsted base, thereby facilitating the activation of nucleophiles and electrophiles simultaneously within the same chiral pocket. In this comprehensive analysis, we provide a thorough account of the advancement and synthetic potential of these diverse catalysts in organic synthesis, while emphasizing the reactivity and selectivities, i.e., dr and ee due to the design/structure of the ligands employed., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Cyclopropanes are of great synthetic value in heterocyclic chemistry due to their highly reactive nature. They are widely employed to synthesize various biologically active organic compounds. Generally, vinyl, carbonyl, imine, and alkylidene cyclopropanes are utilized as efficient synthetic precursors in organic synthesis. The Cloke-Wilson rearrangement of these activated cyclopropanes is carried out to achieve the synthesis of diverse heterocyclic scaffolds. Various oxygen, nitrogen, and sulfur-containing heterocyclic compounds have been synthesized employing this rearrangement. With time, Cloke-Wilson rearrangement has evolved into a high yielding enantioselective and diastereoselective approach utilizing integrated novel methods. Our review focuses on the recent approaches for Cloke-Wilson rearrangement to synthesize several five-membered heterocycles and its applicability towards the natural product syntheses reported during 2000-2020., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

With the ever-increasing scope of organocuprates, a well-established Gilman reagent has been considered as an unprecedented synthetic tool in modern organic chemistry. The broad research profile of the Gilman reagent (R 2 CuLi in THF or Et 2 O) is owing to its propensity to carry out three kinds of reactions, i.e. , epoxide ring opening reactions, 1,4-conjugate addition reactions, and S N 2 reactions in a regioselective manner. This review examines the applications of Gilman reagent in the total synthesis of both abundant and scarce natural products of remarkable synthetic pharmaceutical profile reported since 2011. The presented insights will be of a vital roadmap to general organic synthesis and it will contribute to the development of new natural products and their analogues in future drug discovery., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In the present study, 2-bromo-4-chlorophenyl-2-bromobutanoate ( 3 ) was synthesized via the reaction of 2-bromo-4-chlorophenol with 2-bromobutanoyl bromide in the presence of pyridine. A variety of 2-bromo-4-chlorophenyl-2-bromobutanoate derivatives ( 5a - f ) were synthesized with moderate to good yields via a Pd-catalyzed Suzuki cross-coupling reaction. To find out the reactivity and electronic properties of the compounds, Frontier molecular orbital analysis, non-linear optical properties, and molecular electrostatic potential studies were performed.

Airway mucin secretion is necessary for ciliary clearance of inhaled particles and pathogens but can be detrimental in pathologies such as asthma and cystic fibrosis. Exocytosis in mammals requires a Munc18 scaffolding protein, and airway secretory cells express all 3 Munc18 isoforms. Using conditional airway epithelial cell-deletant mice, we found that Munc18a has the major role in baseline mucin secretion, Munc18b has the major role in stimulated mucin secretion, and Munc18c does not function in mucin secretion. In an allergic asthma model, Munc18b deletion reduced airway mucus occlusion and airflow resistance. In a cystic fibrosis model, Munc18b deletion reduced airway mucus occlusion and emphysema. Munc18b deficiency in the airway epithelium did not result in any abnormalities of lung structure, particle clearance, inflammation, or bacterial infection. Our results show that regulated secretion in a polarized epithelial cell may involve more than one exocytic machine at the apical plasma membrane and that the protective roles of mucin secretion can be preserved while therapeutically targeting its pathologic roles.