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The ability to synthetically tune the ligand frameworks of redox-active molecules is of critical importance to the economy of solar fuels because manipulating their redox properties can afford control over the operating potentials of sustained electrocatalytic or photoelectrocatalytic processes. The electronic and steric properties of 2,2′:6′,2″-terpyridine (Terpy) ligand frameworks can be tuned by functional group substitution on ligand backbones, and these correlate strongly to their Hammett parameters. The synthesis of a new series of tridentate meridional ligands of 2,4,6-trisubstituted pyridines that engineers the ability to finely tune the redox potentials of cobalt complexes to more positive potentials than that of their Terpy analogs is achieved by aryl-functionalizing at the four-position and by including isoquinoline at the two- and six-positions of pyridine (Aryl-DiQ). Their cobalt complex syntheses, their electronic properties, and their catalytic activity for carbon dioxide (CO2) reduction are reported and compared to their Terpy analogs. The cobalt derivatives generally experience a positive shift in their redox features relative to the Terpy-based analogs, covering a complementary potential range. Although those evaluated fail to produce any quantifiable products for the reduction of CO2 and suffer from long-term instability, these results suggest possible alternate strategies for stabilizing these compounds during catalysis. We speculate that lower equilibrium association constants to the cobalt center are intrinsic to these ligands, which originate from a steric interaction between protons on the pyridine and isoquinoline moieties. Nevertheless, the new Aryl-DiQ ligand framework has been engineered to selectively tune homoleptic cobalt complexes' redox potentials. [ABSTRACT FROM AUTHOR]

We report the experimental resonance enhanced multiphoton ionization spectrum of isoquinoline between 315 and 310 nm, along with correlated electronic structure calculations on the ground and excited states of this species. This spectral region spans the origin transitions to a π–π* excited state, which previous work has suggested to be vibronically coupled with a lower lying singlet n–π* state. Our computational results corroborate previous density functional theory calculations that predict the vertical excitation energy for the n–π* state to be higher than the π–π* state; however, we find an increase in the C–N–C angle brings the n–π* state below the energy of the π–π* state. The calculations find two out-of-plane vibrational modes of the n–π* state, which may be brought into near resonance with the π–π* state as the C–N–C bond angle increases. Therefore, the C–N–C bond angle may be important in activating vibronic coupling between the states. We fit the experimental rotational contour with a genetic algorithm to determine the excited state rotational constants and orientation of the transition dipole moment. The fits show a mostly in-plane polarized transition, and the projection of the transition dipole moment in the a-b plane is about 84° away from the a axis. These results are consistent with the prediction of our electronic structure calculations for the transition dipole moment of the π–π* excited state. [ABSTRACT FROM AUTHOR]

The Pummerer rearrangement is extensively utilized for the preparation of various heterocyclic compounds, as well as for the introduction of functional groups such as carbonyl, hydroxyl, and amino groups into organic molecules. The reaction mechanism typically proceeds through an initial electrophilic attack by Lewis acid or another electrophile on the sulfur atom of the sulfoxide, leading to the formation of a sulfonium intermediate. Subsequent rearrangement of this intermediate results in the migration of an alkyl/aryl group from sulfur to a neighboring carbon atom, accompanied by the expulsion of a leaving group. The Pummerer rearrangement of quinoline derivatives has significant synthetic utility and has been employed in the synthesis of various compounds. It has found applications in the synthesis of natural products, agrochemicals, pharmaceuticals, diversity-oriented synthesis, functional group transformations, and other fine chemicals. Overall, The Pummerer rearrangement of quinoline derivatives offers a versatile tool for the synthesis of complex molecules in medicinal chemistry. [ABSTRACT FROM AUTHOR]

ABSTRACT A highly regioselective approach for constructing 4‐cyclobutene‐isoquinoline derivatives through ruthenium‐catalyzed domino C–H activation/cyclization of aryl imidates has been demonstrated. This new transformation tolerates various substituted functional groups on imidates and propargylic monofluoroalkynes, resulting in the corresponding products being delivered in moderate yields. [ABSTRACT FROM AUTHOR]

Herein, we report an efficient strategy towards the synthesis of amino acid substituted isoquinoline derivatives via reaction of unprotected amino acid/amino acid ester/amino acid based drugs with 2‐(2‐oxo‐2‐aryl/alkylethyl)benzonitrile under metal‐free conditions. The developed protocol is highly simple and shows functional group tolerance to provide corresponding novel amino acid substituted isoquinolines in aqueous medium. The applicability of the reaction is an easier modification of well‐known drugs and successfully extended to gram‐scale synthesis. [ABSTRACT FROM AUTHOR]

A novel series of six [1,2,4]triazolo[3,4-a]isoquinolin-3-yl)-3-(1,3-diphenyl-1H-pyrazol-4-yl)prop-2-en-1-ones (3a–3f) was designed and synthesized. They were characterized based on spectral and elemental analyses. In silico studies were also committed to provide insights and a better understanding of their structural features. The six compounds were screened for their antiproliferative activity using the MTT assay against five human cancer cell lines, namely, A549, HCT116, PC3, HT29, and MCF-7 in parallel with the non-cancerous human lung cell line WI-38. The results showed that 3e and 3f have potential cytotoxic activities, especially on A549 cells with IC50 = 2.3 µM and 1.15 µM, respectively. Meanwhile, they recorded a minimal cytotoxic effect on WI-38 cells. Concerning the molecular mechanism of action, the present study showed the inhibitory effect of the six compounds against total EGFR. The most potent EGFR inhibitors were 3e and 3f with IC50 = 0.031 µM and 0.023 µM, respectively. The selectivity index of 3f for EGFRT790M was 1.81 times more selective than that of lapatinib. In addition, 3e and 3f initiated cell cycle arrest at the G2/M and pre-G1 phases along with the downregulation of anti-apoptotic protein Bcl2 and the upregulation of pro-apoptotic proteins: p53, Bax, and caspases 3, 8, and 9. Further studies are recommended to evaluate animal models' promising anticancer activity and molecular mechanism of triazolo[3,4-a]isoquinoline derivatives 3e and 3f. [ABSTRACT FROM AUTHOR]

In this work new isoquinazoline derivatives were synthesized in excellent yields using three component reactions of isoquinoline or its derivatives, isothiocyanates, and 1-(6-amino-2-(prop-1-en-2-yl)benzofuran-5-yl)ethan-1-one in the presence of triethylamine (Et3N) under solvent-free conditions at room temperature. Also, the antioxidant activity of some synthesized isoquinazoline was studied using trapping of radical by DPPH and ferric reduction activity potential (FRAP) experiment. The short time of reaction, high yields of products, easy separation of products are some benefits of this procedure. HIGHLIGHTS: Green chemistry is the use of a set of principles to reduce or eliminate the use or generation of unsafe materials in the design, fabrication and applications of chemical products. Among solvents, water is a green solvents and very suitable for performing organic reaction. The present procedure avoids the use of toxic solvent. Some representatives of this class of N-heterocycles are known as antiviral agents, glycosidase inhibitors, anticancer agents or antidiabetics. Therefore, in view of their medicinal relevance, an increasing number of synthetic methods have been described in recent years for the construction of highly substituted isoquinazoline derivatives. [ABSTRACT FROM AUTHOR]

Dearomative construction of multiply‐fused 2D/3D frameworks, composed of aromatic two‐dimensional (2D) rings and saturated three‐dimensional (3D) rings, from readily available quinolines has greatly contributed to drug discovery. However, dearomative cycloadditions of quinolines in the presence of photocatalysts usually afford 5,6,7,8‐tetrahydroquinoline (THQ)‐based polycycles, and dearomative access to 1,2,3,4‐THQ‐based structures remains limited. Herein, we present a chemo‐, regio‐, diastereo‐, and enantioselective dearomative transformation of quinolines into 1,2,3,4‐THQ‐based 6–6–4‐membered rings without any catalyst, through a combination of nucleophilic addition and borate‐mediated [2+2] photocycloaddition. Detailed mechanistic studies revealed that the photoexcited borate complex, generated from quinoline, organolithium, and HB(pin), accelerates the cycloaddition and suppresses the rearomatization that usually occurs in conventional photocycloaddition. Based on our mechanistic analysis, we also developed further photoinduced cycloadditions affording other types of 2D/3D frameworks from isoquinoline and phenanthrene. [ABSTRACT FROM AUTHOR]

Dearomative construction of multiply‐fused 2D/3D frameworks, composed of aromatic two‐dimensional (2D) rings and saturated three‐dimensional (3D) rings, from readily available quinolines has greatly contributed to drug discovery. However, dearomative cycloadditions of quinolines in the presence of photocatalysts usually afford 5,6,7,8‐tetrahydroquinoline (THQ)‐based polycycles, and dearomative access to 1,2,3,4‐THQ‐based structures remains limited. Herein, we present a chemo‐, regio‐, diastereo‐, and enantioselective dearomative transformation of quinolines into 1,2,3,4‐THQ‐based 6–6–4‐membered rings without any catalyst, through a combination of nucleophilic addition and borate‐mediated [2+2] photocycloaddition. Detailed mechanistic studies revealed that the photoexcited borate complex, generated from quinoline, organolithium, and HB(pin), accelerates the cycloaddition and suppresses the rearomatization that usually occurs in conventional photocycloaddition. Based on our mechanistic analysis, we also developed further photoinduced cycloadditions affording other types of 2D/3D frameworks from isoquinoline and phenanthrene. [ABSTRACT FROM AUTHOR]

The heart is highly sensitive to oxygen deprivation, and hypoxia can lead to cardiomyocyte damage and subsequent cardiac dysfunction. Protopine Pro), an isoquinoline alkaloid derived from various herbs, exhibits diverse biological activities. However, the protective mechanisms of Pro against hypoxia-induced cardiomyocyte damage are not well understood. In this study, Pro was observed to stimulate cell proliferation in H9C2 cardiomyocytes under hypoxia/reoxygenation (H/R) conditions and mitigate apoptosis typically associated with H/R exposure. Despite a notable increase in oxidative stress following H/R treatment, Pro treatment effectively reduced this effect. Additionally, Pro was found to enhance autophagy in H/R-treated H9C2 cells, as evidenced by higher microtubule-associated protein 1 light chain 3 (LC3)-II/LC3-I ratios and increased LC3B fluorescence intensity. The activation of the phosphatase and tensin homolog deleted on chromosome ten (PTEN)/phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway by Pro was also demonstrated. Overall, Pro influences oxidative stress, apoptosis, and autophagy in H9C2 cardiomyocytes under H/R conditions by activating the PTEN/PI3K/Akt pathway, suggesting it as a promising agent to mitigate hypoxia-induced cardiomyocyte damage. [ABSTRACT FROM AUTHOR]

The core structure is an aromatic heterocyclic organic compound i.e. Isoquinoline. Both the structures of Isoquinoline and quinoline contain a fused ring structure of benzene and pyridine. Isoquinoline, the pyridine counterpart, has a pKb of 8.6 and a pKa of 5.14, making it a weak basic. When it comes into contact with Lewis acids, such BF3, it protonates and becomes a salt. This process produces adducts. The liquid form of Isoquinoline is colorless, hygroscopic, and it has an unpleasant smell. Isoquinoline derivatives are a very significant group of natural and synthetic compounds which show various Pharmacological activities like anti-cancer, anti-oxidant, anti-microbial, anti-inflammatory, anti-microbial, analgesic, anti-fungal, anti-viral, antispasmodic and an enzyme inhibitor. Morphine and codeine are the most extensively characterized Isoquinoline alkaloids. They are made from either tyrosine or phenylalanine. Some of the Isoquinoline nucleus-containing drugs available in the market were Nelfinavir, Apomorphine, Quinapril, Praziquantel, Solifenacin, Papaverine, Metocurine, Tubocurarine. Isoquinoline alkaloids with anticancer properties may be therapeutically to target specific binding to nucleic acids, modulating polynucleic acid stability. These binds change the way that duplex B-form DNA interacts with proteins involved in DNA replication, repair, or transcription. [ABSTRACT FROM AUTHOR]

Objective: The purpose of the study was to explore Edaravone and Noscapine in anAlCl3-induced Alzheimer's disease (AD) model. Methods: Morris Water Maze (MWM), Novel Object Recognition (NOR), andY-maze tests with TNF-α, IL-1, IL-6, amyloid-β, CAT, SOD and MDAlevels were performed, followed by brain histology. Results: On the probe trial, the MWM demonstrated a decrease in escape latencyfollowed by an increase in the target quadrant. The NOR showeddiscrimination and recognition index scores and Y-maze, revealed arise in spontaneous alterations. TNF-α, IL-1, IL-6, amyloid-β, CATand MDA levels increased, while SOD levels dropped. The results werefound to be significant for combination full and half doses (***p <0.001, **p < 0.01). The treated group's histology ofbrain revealed mild neurodegeneration with hippocampal pyknoticnuclei. Conclusions: Thus, Edaravone and Noscapine can be used for thetreatment of AD. Abbreviations: AlCl3: Aluminium chloride; AD: Alzheimer's disease; Aβ: Amyloid plaques; APP: amyloid precursor protein; BACE 1: Serum beta-secretase 1; GSK3β: Glycogen synthase kinase 3 β; CDK 5: cyclin-dependent kinase-5; NFTs: neurofibrillary tangles; ROS: reactive oxygen species; JNK: c Jun N-terminal kinases; MWM: Morris Water Maze; NOR: Novel Object Recognition (NOR); TNF-α: Tumor necrosis factor -α; CAT: Catalase; SOD: Superoxide Dismutase; MDA: Malondialdehyde. [ABSTRACT FROM AUTHOR]

Herein, we report a new method for the synthesis of functionalized pyrrole and isoquinoline derivatives using isoxazole based precursors. The reaction proceeds through the ring opening and ring closing cascade mechanism (ROCC) to afford pyrrole or isoquinoline derivatives in good to excellent yields under very mild experimental conditions. Product outcome relies on the strategic placement of different substituents on the isoxazole moiety. The present method is also applicable to synthesize functionalized isoquinolone derivatives. [ABSTRACT FROM AUTHOR]

In this paper, a two‐step process is described for the chemoselective synthesis of highly fluorescent polycyclic chromeno[4,3,2‐ij]isoquinoline‐3‐carbonitriles using a sequential nucleophilic addition reaction involving 4‐chloro‐3‐vinyl coumarins, α,α‐dicyanoolefins and ammonium acetate as a source of nitrogen. In this process, it is believed that ammonium acetate is converted into ammonia and acetic acid during the reaction. Ammonia is the source of nitrogen, and the acid produced can catalyze the progress of the reaction. Single‐crystal X‐ray analysis was performed to confirm the structure of one of the typical products. In addition, the photophysical characteristics of the product 3 a were investigated through absorption and emission spectroscopy. This analysis reveals that the new heterocyclic system has impressive fluorescence characteristics. Several advantages of the presented synthetic strategy can be found in its simplicity, readily available starting materials, high‐efficiency products, highly chemoselective route, metal‐free catalyst, and ability to purify products by washing them with EtOH (96 %), a technique called GAP (Group‐Assisted‐Purification) chemistry. [ABSTRACT FROM AUTHOR]

An enantioselective tandem sequence that comprises a cycloaromatization process followed by an intramolecular desymmetrizing Friedel‐Crafts alkylation of functionalized cyclohexadienones has been accomplished. The process takes place in good yields (65–95%), with excellent diastereoselectivity (>20:1) and enantiomeric ratios up to 90.5:9.5 in the presence of (R)‐BINOL‐derived N‐triflyl phosphoramides, and it gains access to a family of pyrrolo[2,1‐a]isoquinoline derivatives in a simple manner, with the simultaneous generation of two vicinal stereocenters, one of them a tetrasubstituted carbon stereocenter. [ABSTRACT FROM AUTHOR]

The reaction of indigo with two equivalents of the electrophile ethyl bromoacetate with caesium carbonate as a base result in the formation of structurally complex polyheterocyclics, including a fused spiroimidazole and a spiro[1,3]oxazino derivative, together with a biindigoid-type derivative, through a convenient one-pot reaction. Further assessment of the reaction using five equivalents of the electrophile gave rise to other molecules incorporating the 2-(7,13,14-trioxo-6,7,13,14-tetrahydropyrazino[1,2-a:4,3-a′]diindol-6-yl) scaffold. The reaction of ethyl bromoacetate with the less reactive indirubin resulted in the synthesis of three derivatives of a new class of polyheterocyclic system via a cascade process, although yields were low. These compounds were derived from the parent indolo[1,2-b]pyrrolo[4,3,2-de]isoquinoline skeleton. Despite the modest yields of the reactions, they represent quick cascade routes to a variety of heterocycles from cheap starting materials, with these structures otherwise being difficult to synthesise in a traditional stepwise manner. These outcomes also contribute significantly to the detailed understanding of the indigo/indirubin cascade reaction pathways initiated by base-catalysed N-alkylation. [ABSTRACT FROM AUTHOR]

Lamellarins are natural products with a [3,4]-fused pyrrolocoumarin skeleton possessing interesting biological properties. More than 70 members have been isolated from diverse marine organisms, such as sponges, ascidians, mollusks, and tunicates. There is a continuous interest in the synthesis of these compounds. In this review, the synthetic strategies for the synthesis of the title compounds are presented along with their biological properties. Three routes are followed for the synthesis of lamellarins. Initially, pyrrole derivatives are the starting or intermediate compounds, and then they are fused to isoquinoline or a coumarin moiety. Second, isoquinoline is the starting compound fused to an indole moiety. In the last route, coumarins are the starting compounds, which are fused to a pyrrole moiety and an isoquinoline scaffold. The synthesis of isolamellarins, azacoumestans, isoazacoumestans, and analogues is also described. The above synthesis is achieved via metal-catalyzed cross-coupling, [3 + 2] cycloaddition, substitution, and lactonization reactions. The title compounds exhibit cytotoxic, multidrug resistance (MDR), topoisomerase I-targeted antitumor, anti-HIV, antiproliferative, anti-neurodegenerative disease, and anti-inflammatory activities. [ABSTRACT FROM AUTHOR]

The document is the contents list for an issue of the journal Chemical Communications. It includes the titles and authors of various articles and features that will be included in the issue. The articles cover a range of topics in the field of chemistry, including recent advances in biosensing systems, continuous flow synthesis, electrochemical construction, and more. The journal is published by The Royal Society of Chemistry, a leading chemistry community. [Extracted from the article]

An efficient palladium-catalyzed cascade cyclization/carbonylation of indoles with aryl formates to access ester-functionalized indolo[2,1-a]isoquinoline scaffolds has been developed. In addition, an asymmetric variant is also achieved using a chiral phosphine ligand, affording the indolo[2,1-a]isoquinoline products in good yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

Molecular building blocks, capable of adopting several strongly deviating conformations, are of particular interest in the development of stimuli‐responsive self‐assemblies. The pronounced structural flexibility of a short acridone‐based bridging ligand, equipped with two monodentate isoquinoline donors, is herein exploited to assemble a surprisingly diverse series of coordination‐driven Pd(II) architectures. First, it can form a highly twisted Pd2L4 helicate, transformable into the corresponding mesocate, controlled by temperature, counter anion and choice of solvent. Second, it also allows the formation of heteroleptic cages, either from a mix of ligands with Pd(II) cations or by cage‐to‐cage transformation from homoleptic assemblies. Here, the acridone‐based ligand tolerates counter ligands that carry their donors either in a diverging or converging arrangement, as it can rotate its own coordination sites by 90° and structurally adapt to both situations via shape complementarity. Third, by a near 180° rotation of only one of its arms, the ligand can adopt an S‐shape conformation and form an unprecedented C6h‐symmetric Pd6L12 saw‐toothed six‐membered ring. [ABSTRACT FROM AUTHOR]

The synthesized compound 1-(2-chlorophenyl) 6-7-dimethoxy-3-methyl-3,4-dihydroisoquinoline (DIQ) was investigated as a biological agent. Its potential to affect muscle contractility was predicted through in silico PASS analysis. Based on the in silico analysis, its capabilities were experimentally investigated. The study aimed to investigate the effects of DIQ on the ex vivo spontaneous contractile activity (CA) of smooth muscle (SM) tissue. DIQ was observed to reduce the strength of Ca2+-dependent contractions in SM preparations (SMP), possibly by increasing cytosolic Ca2+ levels through the activation of a voltage-gated L-type Ca2+ channel. DIQ potently affected calcium currents by modulating the function of muscarinic acetylcholine receptors (mAChRs) and 5-hydroxytryptamine (5-HT) receptors at a concentration of 50 μM. Immunohistochemical tests showed a 47% reduction in 5-HT2A and 5-HT2B receptor activity in SM cells and neurons in the myenteric plexus (MP), further confirming the effects of DIQ. Furthermore, a significant inhibition of neuronal activity was observed when the compound was co-administered with 5-HT to SM tissues. The conducted experiments confirm the ability of the isoquinoline analog to act as a physiologically active molecule to control muscle contractility and related physiological processes. [ABSTRACT FROM AUTHOR]

A palladium/chiral N,N'-disulfonyl bisimidazoline (Bim)-catalyzed asymmetric addition of arylboronic acids to isoquinoline-1,3,4-trione-derived ketimines is reported, leading to the generation of a series of functionalized isoquinoline-1,3(2H,4H)-diones bearing one quaternary carbon-amino functionality in good to excellent yields with ≥95% ee in most cases. The reaction has remarkable compatibility with both substrate scopes, providing a highly enantioselective entry to chiral heterocyclic a-tertiary amines. [ABSTRACT FROM AUTHOR]

Based on "fentanyl" event, the heterocyclic chemistry curriculum system was improved by using opioid heterocyclic compounds as ideological and political cases, which integrate knowledge transfer, value shaping, and science popularization. The author attempts to use natural analgesic isoquinoline heterocyclic drugs as examples, their physico-chemical properties, synthesis, and application of these isoquinoline heterocyclic drugs are implemented throughout the whole teaching process. The reform of heterocyclic chemistry classroom teaching via case-based teaching methods could effectively aroused students’ enthusiasm as well as initiative for learning, and thus significantly improved the teaching effects. [ABSTRACT FROM AUTHOR]

Objective. BEP (bleomycin, etoposide, and cisplatin) chemotherapy is a standard regimen for germ cell tumors (GCTs); however, their high emetogenicity is problematic. The control of chemotherapy‐induced nausea and vomiting (CINV) is crucial to complete the treatment. We conducted this study to explore the efficacy and safety of antiemetic therapy with dexamethasone and aprepitant for 5 days in combination with palonosetron 0.75 mg on days 1 and 5 in BEP. Methods. This open‐label single‐arm study was prospectively conducted in 4 hospitals. Chemotherapy‐naïve men with GCT who were scheduled to receive the BEP regimen were eligible. The primary endpoint was the complete response (CR) rate of CINV. Results. A total of 19 patients were enrolled. Overall, 16 (84.2%) patients experienced some nausea, whereas only 4 (21.1%) patients had grade 1 emetic events. Overall CR of CINV was achieved in 9 (47.4%) patients. Although 14 (73.7%) patients experienced 22 adverse events after palonosetron administration, severe adverse events (grade 3 or more) attributable to it did not occur. Conclusion. The results suggest that aprepitant, palonosetron, and dexamethasone antiemetic therapy for patients with GCT receiving BEP is safe, whereas the efficacy of additional palonosetron administration on day 5 for prevention of delayed CINV remains unclear. This trial is registered with UMIN000008110. [ABSTRACT FROM AUTHOR]

An efficient method for the synthesis of indolo[2,1-a]isoquinolines using calcium carbide as an alkyne source, 2-(2-bromophenyl)-1H-indoles as starting materials, and copper as a catalyst is described. The target products are synthesized via Sonogashira cross-coupling/nucleophilic addition tandem reactions. The advantages of this protocol include the use of inexpensive and easy-to-handle solid alkyne source instead of flammable and explosive gaseous acetylene, cheap and readily available raw materials, wide range of substrates, and simple reaction procedure. The method can also be extended to gram scale. In addition, the desired product can also be obtained by one-pot three-component reaction of phenylhydrazine hydrochlorides, o-bromoacetophenones and calcium carbide. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive overview of various methods for the synthesis of substituted naphthalene derivatives. Naphthalene is a versatile organic compound with applications in materials chemistry, electronics, and medicine. The synthesis of naphthalene involves metal-catalyzed reactions, such as palladium-catalyzed carboannulation, and yields derivatives with diverse substituents. These derivatives have medicinal importance and exhibit a wide range of therapeutic activities. The article discusses different metal-catalyzed reactions, their mechanisms, and examples of reactions. It also highlights the need for more environmentally friendly approaches to naphthalene synthesis. [Extracted from the article]

Imidazo[1,5‐a]quinolines emit intense blue luminescence, suggesting their possible use as emitter molecules in organic light‐emitting diodes. We synthesized several new imidazo[5,1‐a]isoquinolines and found they possessed a characteristic hypsochromic effect and even increased quantum efficiency compared to the homolog imidazo[1,5‐a]quinolines, as measured by UV‐vis‐ and fluorescence spectroscopy in solution. The energies of the highest occupied and lowest unoccupied molecular orbitals were calculated using density functional theory and experimentally determined by cyclic voltammetry in solution. We obtained a maximum fluorescence quantum yield of 48 % at 446 nm for the newly synthesized 3‐(4‐cyanophenyl)‐1‐(pyridyl)imidazo[5,1‐a]isoquinoline with an optimized substitution pattern. For 1‐phenyl‐3‐(2‐pyridinyl)imidazo[5,1‐a]isoquinoline, a quantum yield of 33 % was obtained at an even shorter emission wavelength of 431 nm. [ABSTRACT FROM AUTHOR]

Chemical Communications is a journal published by The Royal Society of Chemistry, which is a leading chemistry community. The journal features articles on various topics in the chemical sciences. The current issue includes a highlight on the cover, as well as feature articles on topics such as the inhibition of fibril formation by polyphenols and recent advances in circularly polarized luminescence. The journal also provides information on approved training courses offered by The Royal Society of Chemistry. [Extracted from the article]

A new method for the synthesis of a bisbenzylisoquinoline base with a diphenyl oxide fragment based on phosphorane obtained from N-homoveratrylmaleimide has been suggested. [ABSTRACT FROM AUTHOR]

The 1,3-dipolar cycloaddition reaction of substituted dinitroacetonitriles with isoquinoline in the presence of acetylene dicarboxylic acid dimethyl ester results in the formation of a mixture of diastereomeric dimethyl 2-dinitromethyl-1,1bH-pyrimido[2,1-a]isoquinoline-3,4-dicarboxylates. The obtained compounds can be considered as promising synthons with potential antituberculosis and fungicidal activity. [ABSTRACT FROM AUTHOR]

There is good evidence that fatty acid derivatives have antibacterial activity and represent a promising approach to developing the next generation of antibacterial agents. In the present work, some new isoquinolin derivatives were synthesized via the Betti reaction. Three-component reaction of aryl aldehydes, 2,7-naphthalenediol and ammonium carboxylate of fatty acids with different chains in EtOH under reflux conditions offered related isoquinolin compounds in good to excellent yields. Some advantages of this procedure are short reaction times, free catalyst, high yield of products and easy work-up. The structure of synthesized compounds was characterized by IR, 1H, and 13C NMR data as well as microanalysis results. In addition, these novel materials were evaluated for their biological activities against Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) bacteria. The obtained data confirm that isoquinolin derivatives 4c, 4e, 4f, 4g, 4m, 4n, 4p, 4q exert excellent antimicrobial activity against these tested bacterial strains. [ABSTRACT FROM AUTHOR]

The building of N-heterocyclic cores endures an influential area of research due to their ubiquitous presence in natural products, agrochemicals, and small bioactive molecules. Over the past two decades, the synthesis of N-heterocycles via C-H activation comes out as a dominating synthetic protocol in atom-economic manner. The creation of C-C/C-N bonds acts as a key determining step for the building of nitrogen-based heterocycles via direct C-H activation protocol, which could serve as a fascinating concept. In recent years, Group 9 (Co, Rh & Ir) transition metal emerged as a robust catalytic system for the development of valuable N-heterocyclic scaffolds among other transition metals due to their mild reaction conditions, high reactivity, and functional group tolerance. A diverse type of arenes such as anilines/anilides, benzamides, hydrazones, ketoximes, benzylamine, and N-aryl nitrones were subjected to the C-H bond activation for the annulation reaction. Moreover, unsaturated compounds such as alkyne and olefin as coupling partners are again the most used companions for the same purpose, i.e., formation of N-heterocycles. Therefore, this review centers on the up-to-date reports on N-heterocycles synthesis by implementing alkynes and olefins as coupling partners through Group 9 transition metals' catalysis. The methodologies will be based on the coupling of alkynes and olefin, which preferably react in an intermolecular fashion. The scope, limitation, and mechanistic investigation of the Group 9 metal-activated C-H functionalization for the access of N-containing heterocycles with unsaturated reacting partners are the primary focus of the current review. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Chemical Communications" published in 2024. It includes a variety of articles on topics such as cell-free synthetic biology, metal-organic framework-based materials for cancer therapy, and the formation of iminium ions in metal halide perovskites. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document provides a glimpse into the research and discoveries in the field of chemistry. [Extracted from the article]

In this study, a Rh(III)-catalyzed C–H/N–H [4+2] annulation of oxadiazolones with iodonium ylides has been developed, which afforded a series of diverse fused-isoquinolines and fused-pyridines in moderate to high yields. These divergent synthesis protocols featured mild conditions, broad substrate scope, and functional-group compatibility. In addition, scale-up synthesis, related applications and preliminary mechanistic explorations were also accomplished. [ABSTRACT FROM AUTHOR]

C(sp2)−H functionalization offers an efficient strategy for the synthesis of various elaborated N‐containing heteroarenes. Along these lines, oxazino pyridines that can be readily prepared from pyridines, have been introduced as powerful substrates in radical‐ and ionic‐mediated meta‐C−H functionalization. However, the regioselective meta‐C−H arylation of pyridines remains a great challenge. Herein, a copper‐catalyzed meta‐selective C−H arylation of pyridines and isoquinolines through bench‐stable dearomatized intermediates is reported. Electrophilic aryl‐Cu(III) species, generated from readily accessible aryl I(III) reagents, enable the efficient meta‐arylation of a broad range of pyridines and isoquinolines. The method also allows the meta‐selective alkenylation of these heteroarenes using the corresponding alkenyl I(III)‐reagents. Late‐stage arylation of drug‐derived pyridines and larger‐scale experiments demonstrate the potential of this synthetic methodology. [ABSTRACT FROM AUTHOR]

C(sp2)−H functionalization offers an efficient strategy for the synthesis of various elaborated N‐containing heteroarenes. Along these lines, oxazino pyridines that can be readily prepared from pyridines, have been introduced as powerful substrates in radical‐ and ionic‐mediated meta‐C−H functionalization. However, the regioselective meta‐C−H arylation of pyridines remains a great challenge. Herein, a copper‐catalyzed meta‐selective C−H arylation of pyridines and isoquinolines through bench‐stable dearomatized intermediates is reported. Electrophilic aryl‐Cu(III) species, generated from readily accessible aryl I(III) reagents, enable the efficient meta‐arylation of a broad range of pyridines and isoquinolines. The method also allows the meta‐selective alkenylation of these heteroarenes using the corresponding alkenyl I(III)‐reagents. Late‐stage arylation of drug‐derived pyridines and larger‐scale experiments demonstrate the potential of this synthetic methodology. [ABSTRACT FROM AUTHOR]

Background: Schistosomiasis affects approximately 230 million people worldwide. There is an increased incidence of schistosomiasis cases in France acquired from outside the country. This increases the risk of schistosomiasis outbreaks as observed in Corsica. Clinicians from non-endemic regions are not accustomed to diagnosing and managing this pathology. The objective of this study is to provide a better description of the clinical and paraclinical characteristics and disease evolution of affected children. Methods: Through the French Pediatric Nephrology Society and the Pediatric Infectious Pathology Group, we contacted all French pediatric centers that may have treated children with urinary schistosomiasis between 2013 and 2019. Age, sex, comorbidities, and clinical, biological, and radiological data (at discovery and follow-up) were collected retrospectively. Results: A total of 122 patients from 10 different centers were included. The median age was 14 years and the sex ratio M/F was 4:1. Hematuria was present in 82% of the patients while urinary tract abnormality was found in 36% of them. Fourteen patients (11%) displayed complicated forms of urinary schistosomiasis including 10 patients with chronic kidney disease. A total of 110 patients received treatment with praziquantel, which was well-tolerated and led to clinical resolution of symptoms in 98% of cases. Conclusion: Patients with schistosomiasis present frequent kidney, urinary, or genital involvement. Systematic screening of patients returning from endemic areas is therefore recommended, especially since treatment with antiparasitic drugs is effective and well-tolerated. Enhancing medical knowledge of this pathology among all practitioners is essential to improve care and outcomes. [ABSTRACT FROM AUTHOR]

In this work we synthesized imidazolidine derivatives in excellent yields using multicomponent reactions of phthalaldehyde or its derivatives, primary amines, isothiocyanate, 2,4-dihydroxyacetophenone and isopropenylacetylene in the presence of catalytic amount of Ag/KF/CP@MWCNTs NCs in water at room temperature. Also, the catalytic activity of the green synthesized Ag/KF/CP@MWCNTs NCs was evaluated in the reduction of organic pollutants such as 4-nitrophenol (4-NP) in water at mild conditions. The results indicated that the biosynthesized NCs have very high and effective catalytic activity for organic pollutants within few seconds. As well the antioxidant activity of some synthesized imidazolidine was studied using trapping of radical by DPPH and ferric reduction activity potential (FRAP) experiment. Also, the antimicrobial activity of some synthesized compounds proved by employing the disk diffusion test on Gram-positive and Gram-negative bacteria. Also, to better understanding reaction mechanism density functional theory (DFT) based quantum chemical methods have been applied. The short time of reaction, high yields of product, easy separation of catalyst and products are some benefits of this procedure. Green chemistry is the use of a set of principles to reduce or eliminate the use or generation of unsafe materials in the design, fabrication and applications of chemical products. Among solvents, water is a green solvents and very suitable for performing organic reaction. The present procedure avoids the use of toxic solvent. Heterocyclic compounds hold a prominent position in medicinal chemistry owing to their wide spectrum of biological activities such as antimalarial, antimicrobial, antitumor, anticancer, antidepressant, antiviral, antidiabetic, anti-inflammatory and anti-HIV. Imidazolidine-2-one moiety found in variety of biologically active compounds, for example, aplysinopsin is exhibiting cytotoxicity toward cancer cells, nilutamide use for the treatment of advanced prostate cancer. [ABSTRACT FROM AUTHOR]

The biodeterioration of archaeological mummies is a severe issue, where fungi are the most significant agents deteriorating them. The inhibitory effect of [1,2,4]triazolo[3,4-a]isoquinoline chalcone derivatives on the growth of thirteen deteriorated fungal species (Aspergillus flavus, A. niger, A. terreus, Athelia bombacina, Aureobasidium iranianum, Byssochlamys spectabilis, Cladosporium cladosporioides, C. ramotenellum, Penicillium crustosum, P. polonicum, Talaromyces atroroseus, T. minioluteus, and T. purpureogenus), which isolated and identified from ancient Egyptian mummy cartonnage located in El-Lahun regions, Fayoum government, Egypt were investigated. Antifungal activity and minimal inhibitory concentration (MIC) of the tested four chalcone derivatives with different concentrations (1, 2, 3, 4, 5, 6 mg/ml) were measured. The most efficient chalcone derivatives are chalcone derivative number 4 which causes the maximum significant inhibition in the growth of the thirteen isolated fungal species with MIC ranging from 1 to 3 mg/ml followed by chalcone derivatives number 6 with MIC ranging from 2 to 5 mg/ml. The use of chalcone derivative number 4 for the preservation of cultural assets should be considered for future applications. [ABSTRACT FROM AUTHOR]

While a pharmaceutically intriguing scaffold, 5,6‐dihydropyrrolo[2,1‐a]isoquinoline (DHPIQ), has precedently been prepared from diverse tetrahydroisoquinolines (THIQs) using elaborate conditions, convenient metal‐free methods were discovered from condensation of cyanomethylene‐THIQ (1) and α‐halo‐ketones or aldehydes (1a) to afford 15 DHPIQs (2–16) in moderate yields by employing unique reactivities of the secondary amine and α‐carbon to the nitrile of 1. Preliminary biological studies with chronic myelogenous leukemia K562 and adriamycin‐resistant K562 (K562/ADM) cells exhibited some of the DHPIQs tested were active in the both cell lines. In particular, cyclohexyl‐fused DHPIQ (10) showed GI50 values of 9.79 and 13.60 μM in K562 and K562/ADM cells, respectively. Based on the flow cytometry analysis of 10, the anti‐cancer activity could be from apoptosis‐related mechanisms. Overall, this DHPIQ scaffold may be further optimized to discover clinically meaningful anti‐leukemic agents overcoming adriamycin resistance. [ABSTRACT FROM AUTHOR]

Co(III)-catalysed site-selective C8-allylation and vinylation of isoquinolones with allyl acetate and vinyl acetates has been accomplished. The oxo group of isoquinolone has been utilised as an inherent directing group. Based on preliminary mechanistic studies, a plausible mechanism for the developed reaction has also been delineated. Broad substrate scope with good to excellent yields and post-synthetic transformations of allylated and vinylated isoquinolines highlight the importance of the reaction. [ABSTRACT FROM AUTHOR]

A pyrrolo[2,1-a]isoquinoline core structure is prevalent in marine and other natural products. This article describes a tungsten-catalyzed [3+2] cycloaddition aromatization of dihydroisoquinoline ester and maleic anhydride or an acrylate. The photochemical reaction tolerates a range of functional groups such as ester, cyano, ketone, bromide, and alkene. It is shown that the cycloaddition-aromatization of 2-substitued acrylate catalyzed by a tungsten photocatalyst can be used to evaluate the leaving ability of the leaving group. Experiments done to determine the reaction mechanism revealed that the formation of an ion-pair intermediate generated in situ from dihydroisoquinoline ester and (Z)-4-methoxy-4-oxobut-2-enoic acid via the solvolysis of maleic anhydride with methanol is crucial for the cascade process to occur. The key cycloadduct acid intermediate derived from [3+2] cycloaddition was isolated and determined by X-ray crystallography. [ABSTRACT FROM AUTHOR]

A mild nitration of pyrrolo[2,1‐a]isoquinolines has been reached using sodium nitrite as nitro source in HFIP at ambient temperature. A variety of nitro‐bearing pyrrolo[2,1‐a]isoquinoline derivatives has been efficiently prepared in poor to quantitative yields (28–98 %). These products can be easily transformed to primary amines and amide by simple chemical reactions. Treatment of other nitrogen‐containing heterocycles such as pyrrolo[1,2‐a]quinoline and substituted indoles under this developed reaction system afforded nitro‐bearing N‐heterocycles in relatively lower yields (15–19 %). [ABSTRACT FROM AUTHOR]

This study presents a comprehensive structural analysis of the adducts formed upon the reaction of two Ru(III) complexes [HIsq][trans-RuIIICl4(dmso)(Isq)] (1) and [H2Ind][trans-RuIIICl4(dmso)(HInd)] (2) (where HInd-indazole, Isq-isoquinoline, analogs of NAMI-A) and two Ru(II) complexes, cis-[RuCl2(dmso)4] (c) and trans-[RuCl2(dmso)4] (t), with hen-egg white lysozyme (HEWL). Additionally, the crystal structure of an adduct of human lysozyme (HL) with ruthenium complex, [H2Ind][trans-RuCl4(dmso)(HInd)] was solved. X-ray crystallographic data analysis revealed that all studied Ru complexes, regardless of coordination surroundings and metal center charge, coordinate to the same amino acids (His15, Arg14, and Asp101) of HEWL, losing most of their original ligands. In the case of the 2-HL adduct, two distinct metalation sites: (i) Arg107, Arg113 and (ii) Gln127, Gln129, were identified. Crystallographic data were supported by studies of the interaction of 1 and 2 with HEWL in an aqueous solution. Hydrolytic stability studies revealed that both complexes 1 and 2 liberate the N-heterocyclic ligand under crystallization-like conditions (pH 4.5) as well as under physiological pH conditions, and this process is not significantly affected by the presence of HEWL. A comparative examination of nine crystal structures of Ru complexes with lysozyme, obtained through soaking and co-crystallization experiments, together with in-solution studies of the interaction between 1 and 2 with HEWL, indicates that the hydrolytic release of the N-heterocyclic ligand is one of the critical factors in the interaction between Ru complexes and lysozyme. This understanding is crucial in shedding light on the tendency of Ru complexes to target diverse metalation sites during the formation and in the final forms of the adducts with proteins. [ABSTRACT FROM AUTHOR]

Due to boron's metalloid properties, aromatic boron reagents are prevalent synthetic intermediates. The direct borylation of aryl C-H bonds for producing aromatic boron compounds offers an appealing, one-step solution. Despite significant advances in this field, achieving regioselective aryl C-H bond borylation using simple and readily available starting materials still remains a challenge. In this work, we attempted to enhance the reactivity of the electron-donor-acceptor (EDA) complex by selecting different bases to replace the organic base (NEt3) used in our previous research. To our delight, when using NH4HCO3 as the base, we have achieved a mild visible-light-mediated aromatic C-H bond borylation reaction with exceptional regioselectivity (rr > 40:1 to single isomers). Compared with our previous borylation methodologies, this protocol provides a more efficient and broader scope for aryl C-H bond borylation through the use of N-Bromosuccinimide. The protocol's good functional-group tolerance and excellent regioselectivity enable the functionalization of a variety of biologically relevant compounds and novel cascade transformations. Mechanistic experiments and theoretical calculations conducted in this study have indicated that, for certain arenes, the aryl C-H bond borylation might proceed through a new reaction mechanism, which involves the formation of a novel transient EDA complex. [ABSTRACT FROM AUTHOR]

Objective To determine if the prevalence of schistosomiasis in children aged 9--12 years is associated with the prevalence in 5--8-year-olds and adults after preventive chemotherapy in schools or the community. Methods We combined data from four community-randomized, preventive chemotherapy trials in treatment-naïve populations in Côte d'Ivoire, Kenya and the United Republic of Tanzania during 2010--2016 according to the number of praziquantel treatments and the delivery method. Schistosoma mansoni infection was sought on two slides prepared from each participant's first stool using the Kato--Katz technique. We assessed associations between S. mansoni prevalence in 9--12-year-olds and 5--8-year-olds and adults in the community before and after treatment using Bayesian regression models. Findings Stool samples from 47 985 5--8-year-olds, 81 077 9--12-year-olds and 20 492 adults were analysed. We found associations between the prevalence in 9--12-year-olds and that in 5--8-year-olds and adults after preventive treatment, even when only school-age children were treated. When the prevalence in 9--12-year-olds was under 10%, the prevalence in 5--8-year-olds was consistently under 10%. When the prevalence in 9--12-year-olds was under 50%, the prevalence in adults after two or four rounds of preventive chemotherapy was 10%--15% lower than before chemotherapy. Post-chemotherapy age-group associations were consistent with pre-chemotherapy associations in this analysis and previous studies. Conclusion The prevalence of S. mansoni infection in 9--12-year-olds was associated with the prevalence in other age groups and could be used to guide community treatment decisions. [ABSTRACT FROM AUTHOR]

The reaction 5-(arylmethylidene)-2,4,6-pyrimidine-2,4,6(1H,3H,5H)-triones with isoquinoline and dimethyl but-2-ynedioate gave cycloaddition products, mixtures of diastereoisomeric substituted dimethyl 2-aryl-2′,4′,6′-trioxo-1′,3′,4′,6′-tetrahydro-2H,2′H,11bH-spiro[pyrido[2,1-a]isoquinoline-1,5′-pyrimidine]-3,4-dicarboxylates which were converted to the corresponding dipotassium salts by treatment with excess potassium hydroxide in ethanol. The synthesized compounds are of interest as promising intermediate products with potential antitubercular and fungicidal activities. [ABSTRACT FROM AUTHOR]

The Ritter reaction of dialkyl benzyl carbinols with 3-methoxy- and 3-phenoxypropanenitriles afforded the corresponding 1-(2-methoxyethyl)- and 1-(2-phenoxyethyl)-3,3-dialkyl-3,4-dihydroisoquinolines. Likewise, benzo[f]isoquinoline derivatives were synthesized from 2-methyl-3-(naphthalen-1-yl)-propan-2-ol. The obtained compounds were shown to have the imine structure, but they exhibited enamine properties. In particular, their reactions with oxalyl chloride resulted in pyrrole annulation. [ABSTRACT FROM AUTHOR]