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The development of efficient multi‐resonance thermally activated delayed fluorescence (MR‐TADF) materials with ultra‐narrowband emission presents an ongoing challenge. In this work, a carbazole‐fused dual‐boron embedded MR‐TADF framework is proposed, achieving three emitters, CFDBO, CFDBA, and CFDBCz, via one‐shot borylation with very high yields of over 70%. The emitters display ultra‐narrowband blue emission with peaks ranging from 452 to 479 nm and small full width at half maximum (FWHM) values of only 16–18 nm in dilute toluene solutions. Furthermore, the organic light‐emitting diode (OLED) incorporating CFDBO exhibits pure‐blue emission with a peak of 460 nm and Commission International de l'Eclairage coordinates of (0.14, 0.12). Meanwhile, OLEDs incorporating CFDBA/CFDBCz demonstrate remarkable performances with high external quantum efficiencies of 30.9%/32.4% and exceptionally slender FWHM values of 21/22 nm, representing outstanding performances among reported MR‐TADF materials. [ABSTRACT FROM AUTHOR]

Blue LEDs‐irradiation of a mixture of N,N,N',N'‐tetramethylethylenediamine (TMEDA) and perfluoroalkyl iodides (RF−I) – Electron Donor Acceptor (EDA)‐complex – in the presence of triphenylamines (TPAs) in an aqueous solvent mixture afforded mono‐perfluoroalkylated triphenylamines (RF−TPA) in good yields. These RF−TPA were further subjected to acetone‐sensitized [6π]‐electrocyclization at 315 nm‐irradiation affording exclusively perfluoroalkylated endo‐carbazole derivatives (RF−CBz) in quantitative yields. Mechanistic studies and photophysical properties of products are studied. [ABSTRACT FROM AUTHOR]

Chemical Communications is a journal published by The Royal Society of Chemistry, which aims to connect the world with the chemical sciences. The contents list of the journal includes articles on various topics such as electrosynthesis of H2O2, metal chalcogenide semiconductors for thin film photovoltaics, and Passerini polymerization. The journal also features articles on topics like organic hole transport materials for quantum dot solar cells and wide temperature battery operation with hybrid lithium electrolytes. The articles cover a range of research areas in the field of chemistry. [Extracted from the article]

A gold(I)-catalyzed protecting-group-free benzannulation approach to functionalized NH-carbazoles was accomplished via the hydroarylation of alkynes with 2-alkenylindoles. A broad spectrum of terminal and internal alkynes and 2-alkenylindoles successfully participated in this annulation reaction. The protocol efficiently enabled the formation of substituted NH-carbazoles with moderate to specific regioselectivities. The synthetic utility of this protocol was demonstrated by a variety of post-functionalizations. [ABSTRACT FROM AUTHOR]

A series of near‐IR absorbing 2,6‐diarylated BF2‐chelated aza‐boron‐dipyrromethenes (aza‐BDPs) derivatives bearing different electron donors (benzene, naphthalene, phenanthrene, phenothiazine and carbazole) were designed and synthesized. The effect of different electron donor substitutions on the photophysical properties was studied by steady‐state UV‐vis absorption and fluorescence spectra, electrochemical, time‐resolved nanosecond transient absorption (ns‐TA) spectroscopy and theoretical computations. The UV‐vis absorption spectra of AzaBDP‐PTZ and AzaBDP‐CAR (λabs=710 nm in toluene) showed a bathochromic absorption profile compared with the reference AzaBDP‐Ph (λabs=685 nm in toluene), indicating the non‐negligible electronic interaction at the ground state between donor and acceptor moieties. Moreover, the fluorescence is almost completely quenched for AzaBDP‐PTZ/AzaBDP‐CAR (fluorescence quantum yield, ΦF=0.2–0.7 % in toluene) as compared with the AzaBDP‐Ph (ΦF=27 % in toluene). However, the apparent intersystem crossing ability of these compounds is poor, based on the singlet oxygen quantum yield (ΦΔ=0.3–1.5 %). The ns‐TA spectral study showed typical Bodipy localized triplet state transient features, short‐lived excited triplet state for AzaBDP‐Ph (τT=53.2 μs) versus significantly long‐lived triplet state for AzaBDP‐CAR (τT=114 μs) was observed under deaerated experimental conditions. These triplet state lifetimes are much longer than that obtained with diiodoAzaBDP (intramolecular heavy atom effect, τT=1.5~7.2 μs). These information are useful for molecular structure design of triplet photosensitizers, for which longer triplet state lifetimes are usually desired. Theoretical computations displayed that the triplet state is mainly localized on the AzaBDP core, moreover, it was found that the HOMO/LUMO energy gap decreased after introducing donor moieties to the skeleton as compared with the reference. [ABSTRACT FROM AUTHOR]

Achieving control over the polymerization of less activated monomers like N‐vinyl carbazole (NVC), N‐vinyl pyrrolidone (NVP), and N‐vinyl imidazole (NVIm) to produce high molar mass polymers poses a significant challenge. To accomplish this, eight different dithiocarbamate‐based reversible addition–fragmentation chain transfer (RAFT) agents are synthesized and employed to polymerize NVIm, NVC, and NVP in order to understand and establish a suitable agent for their controlled polymerization to achieve high molar mass polymers. Chain end presence of these RAFT‐derived polymers is established through 1H NMR studies. Further, these active chain ends are used for chain extension reactions to prepare block copolymers. Synthesized RAFT agents 04, 05, 06, and 08 that are bearing primary leaving groups (methyl 2‐acetate, ethyl 2‐acetate, tert‐butyl 2‐acetate, and cyanomethane) display moderate to good control over the polymerization of NVIm and NVC. Among these, RAFT agent‐08 with cyanomethane leaving group produces poly(NVIm) and poly(NVC) with the highest molar masses of 44 670 Da (1.52) and 53 620 Da (1.4), respectively. Interestingly, RAFT agents bearing both secondary and primary leaving groups show good control over the NVP polymerization. Notably, RAFT agent‐02 with ethyl‐2‐propionate leaving group yields poly(NVP) with the highest molar mass of 89 450 Da and dispersity of 1.43. [ABSTRACT FROM AUTHOR]

A mononuclear, T‐shaped palladium(I) d9 metalloradical (3), stabilized by a bulky carbazole‐based PNP‐ligand, was obtained by reduction of palladium chloride or thermal Pd−C bond homolysis of the corresponding neopentyl complex. Pressurizing with CO gave the Pd(I) carbonyl complex, which was structurally characterized by X‐ray diffraction. Delocalization of the unpaired electron to the carbonyl carbon was detected by EPR spectroscopy and theoretically modeled by DFT and ab initio methods. The partially reduced and radicalized CO slowly reacts with di(tert‐butyl) disulfide under homolytic S−S cleavage and C−S bond formation to give the corresponding metallathioester. [ABSTRACT FROM AUTHOR]

The document is the contents list for the journal "Chemical Communications" published on May 7, 2024. It includes a feature article on the chemistry of gold( I)– ethylene complexes, as well as several communications on various topics such as catalysis, organic synthesis, and electrochemistry. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document provides a list of articles and authors, along with images and permissions for reproduction. [Extracted from the article]

A calix[3]carbazole-based cavitand was conveniently synthesized. It was found that the cavitand with adjustable conformation could show excellent complexation with fullerenes C60 and C70 in both solution and the solid state. Moreover, the crystal structures of the host–guest complexes show that the cavitand can stack into channel-like architectures, in which fullerenes are orderly arranged inside. [ABSTRACT FROM AUTHOR]

This article discusses a new method for synthesizing benzo[b]carbazoles, which are compounds with various applications in medicinal chemistry and materials science. The researchers also explored the liquid crystalline properties of these compounds and successfully achieved a rare nematic phase at room temperature. By fusing a benzene ring and tethering two alkoxyphenyl units, they were able to stabilize the nematic phase. The degree of order in the liquid crystals was influenced by the length of the alkyl chains. This research highlights the significance of innovative molecular designs in creating functional materials. [Extracted from the article]

Experimental and theoretical study of the regioselectivity and mechanism of polycyclic aromatic amine (PAA) electrochemical oxidation is important for designing nitrogen doped large π‐conjugated functional molecules. Herein, we used binary‐, ternary‐, and quaternary‐fused PAAs as electro‐oxidative reaction substrates to investigate the yield changes of carbazole and phenazine based aza‐helicene other than oligomers, which were obtained through pyrrole and pyrazine annulation pathways. Combined with the restrained electrostatic potential (RESP) and steric hindrance factor analysis of the substrate, the electron spin density distribution of free radical resonance hybrid and the spin population analysis of the atoms in the structure of each free radical tautomer indicate that the degree of delocalized dispersion of N free radical and the resulting change in the spin density distribution of C free radical tautomers determine the reaction regioselectivity. The potential charge of the K‐region, Bay‐region, and L‐region adjacent to the C(α)−C(β1) bond is higher than that of other regions within the molecule, and the charge in these high RESP regions tends to delocalize more strongly toward electron‐deficient N free radicals. Thus, the activity of N−C(α)−C(β1) region is increased, which supports the proposed free radical addition and free radical coupling mechanism for the electro‐oxidative reaction of PAA. [ABSTRACT FROM AUTHOR]

The main aim of our study is to investigate various types of hybrid systems with a paramagnetic iron (III) ion as a core and photoactive derivatives of carbazole at the periphery. We have synthesized a variety of biligand coordination compounds with the composition [FeL2]A (where L is 2‐[2‐[(E)‐[4‐[4‐(3,6‐di‐tert‐butylcarbazol‐9‐yl)benzoyl]oxy‐2‐phenolate]methyleneamino]ethylamino]ethyl 4‐(3,6‐di‐tert‐butylcarbazol‐9‐yl)benzoate, A− is NO3− (I), Cl− (II), PF6− (III)). These systems were studied by superconducting quantum interference device (SQUID) magnetometry and X‐band electron paramagnetic resonance (EPR) spectroscopy. Magnetic measurements revealed mixed spin states (high spin [HS], low spin [LS]) of Fe (III) ions at room temperatures. Estimates of the corresponding spin contributions were made. It was found that all samples exhibit AFM exchange interactions between iron (III) ions. The ground spin state at 2.0 K was established and analyzed. EPR measurements confirmed the HS states of iron (III) and revealed two types of them: with weak distorted and strong low‐symmetry octahedral crystal fields. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescent emitters based on carbazole donor, benzonitrile acceptor with the linkers biphenyl, bipyridine and naphthalene are investigated using the density functional theoretical method. The molecule in which bipyridine acts as the linker with the least ΔEST is further selected for the designing of a series of D-L-A framework TADF molecules. Remarkably, the ΔEST is decreased successively by attaching the additional cyano groups at the acceptor site which is further reduced when the electron donating methoxy groups are attached at the donor site. To know the effect of substituents on ΔEST, the acceptor moiety of the D-L-A framework is modified with -F, -Cl and -CF3 substituents. The studies showed a relatively less decrement in the value of ΔEST compared to the cyano substituted molecules. However, ΔEST significantly reduced further on attaching methoxy groups at the donor site. [ABSTRACT FROM AUTHOR]

Context: In this study, we have developed four new chromophores (TM1–TM4) and performed quantum chemical calculations to explore their nonlinear optical properties. Our focus was on understanding the impact of electron-donating substituents on 1,3,4-oxadiazole derivative chromophores. The natural bond orbital analysis confirmed the interactions between donors and acceptors as well as provided insights into intramolecular charge transfer. We also estimated dipole moment, linear polarizability molecular electrostatic potential, UV–visible spectra, and first hyperpolarizability. Our results revealed that TM1 with a strong and stable electron-donating group exhibited high first hyperpolarizability (β) 293,679.0178 × 10−34 esu. Additionally, TM1 exhibited a dipolar moment (μ) of 5.66 Debye and polarizability (α) of 110.62 × 10−24 esu when measured in dimethyl sulfoxide (DMSO) solvent. Furthermore, in a benzene solvent, TM1 showed a low energy band gap of 5.33 eV by using the ωB97XD functional with a 6–311 + + G(d, p) basis set. Moreover, our study of intramolecular charge transfers highlighted N, N dimethyl triphenylamine and carbazole as major electron-donating groups among the four 1,3,4-oxadiazole derivative chromophores. This research illustrates the potential applications of these organic molecules in photonics due to their versatile nature. Methods: The molecules were individually optimized using different functionals, including APFD, B3LYP, CAM B3LYP, and ωB97XD combined with the 6–311 + + G (d, p) basis set in Gaussian 16 software. These methods encompass long-range functionals such as APFD and B3LYP, along with long-range corrected functionals like CAM B3LYP and ωB97XD. The employed functionals of APFD, B3LYP, CAM B3LYP, and ωB97XD with the 6–311 + + G (d,p) basis set were used to extract various properties such as geometrical structures, dipole moment, molecular electrostatic potential, and first hyperpolarizability through precise density functional theory (DFT). Additionally, TD-DFT was utilized for obtaining UV–visible spectra. All studies have been conducted in both gas and solvent phases. [ABSTRACT FROM AUTHOR]

This article provides an overview of heteroatom-embedded polycyclic aromatic compounds (hetero-PACs) and their importance in various scientific and technological fields. Hetero-PACs are structurally diverse compounds that contain multiple fused aromatic rings and embedded heteroatoms such as boron, nitrogen, oxygen, phosphorus, and sulfur atoms. They exhibit diverse optoelectronic properties and have applications in organic electronics and chemical biology. The article discusses the stepwise synthesis of hetero-PACs and the challenges associated with it. It then introduces the concept of heteroatom-embedding annulative π-extension (hetero-APEX) reactions as a more efficient synthetic strategy for hetero-PACs. Hetero-APEX reactions allow for the direct construction of fused heteroaromatic structures, offering advantages in terms of step-economy and late-stage tunability. The article concludes by highlighting the potential of hetero-APEX reactions in expanding the structural diversity of hetero-PACs and promoting the discovery of novel heteroaromatics with unique structures, properties, and functions. [Extracted from the article]

To develop a deep-blue emitter, a molecule with bipolar characteristics was designed as a donor-spacer-acceptor type, in which 9-(4-(4,6-diphenyl-1),3,5-triazin-2-yl)-2,5-dimethylphenyl)-9H-carbazole (DTPCZ)—with carbazole as an electron donating group and a diphenyl triazine moiety as an electron accepting group—was successfully synthesized. The photoluminescence (PL) maxima of DTPCZ were 421 nm in the solution state and 425 nm in the film state, indicating emission in the deep-blue region. DTPCZ also exhibited high thermal stability, with a degradation temperature of 349 °C. To confirm the electroluminescence (EL) characteristics, DTPCZ was applied as a dopant at 10, 20, and 30 wt% in a blue-fluorescent organic light-emitting diode (OLED) device. The highest efficiency was achieved using the 20 wt% doped device, with a current efficiency of 1.2 cd/A, an external quantum efficiency of 2.3%, and a Commission Internationale de l'Eclairage proceedings y-value of 0.06. Thus, deep-blue emission could be realized in the film state. These molecular design strategies can be applied to various fields, such as organic semiconductors. [ABSTRACT FROM AUTHOR]

Organic ultralong room-temperature phosphorescence (RTP) usually emerges instantly and immediately decays after excitation removal. Here we report a new delayed RTP that is postponed by dozens of milliseconds after excitation removal and decays in two steps including an initial increase in intensity followed by subsequent decrease in intensity. The delayed RTP is achieved through introduction of phosphines into carbazole emitters. In contrast to the rapid energy transfer from single-molecular triplet states (T1) to stabilized triplet states (Tn*) of instant RTP systems, phosphine groups insert their intermediate states (TM) between carbazole-originated T1 and Tn* of carbazole-phosphine hybrids. In addition to markedly increasing emission lifetimes by ten folds, since TM → Tn* transition require >30 milliseconds, RTP is thereby postponed by dozens of milliseconds. The emission character of carbazole-phosphine hybrids can be used to reveal information through combining instant and delayed RTP, realizing multi-level time resolution for advanced information, biological and optoelectronic applications. Room-temperature phosphorescence usually occurs immediately after the removal of excitation. Here the authors achieve combined instant and delayed phosphorescence through introduction of phosphines into carbazole emitters. [ABSTRACT FROM AUTHOR]

A series of charge transfer cocrystals with fluorescence properties involving 1,2,4,5-tetracyanobenzene (TCNB, C10H2N4) as acceptor, fluorene (FR, C13H10) and its bromide 2-bromofluorene (2-BrFR, C13H9Br), carbazole (CZ, C12H9N) and its bromide 2-bromocarbazole (2-BrCZ, C12H8BrN) as donor were synthesized via cocrystal design strategies. The formation mechanism of the crystal structure was explored by density functional theory at the molecular level. The stacking structure of the cocrystal was formed by the combination of charge transfer interactions, π–π interactions and hydrogen bonding. The N atom of donors in TCNB–CZ and TCNB–2-BrCZ could enhance the charge transfer, appearing as a red shift of the fluorescence emission wavelength. Conversely, the Br atom in TCNB–2-BrFR and TCNB–2-BrCZ weakens the charge transfer, giving a blue shift in the fluorescence emission spectrum. The four new cocrystals exhibit tunable luminescence from green (529 nm) to yellow (552 nm) and to red (604 nm and 614 nm). It was found that the introduction of N and Br atoms in the assembly units can not only regulate the luminescence range of the cocrystals, but also adjust the luminescence efficiency, which provides a strategy for the development of promising organic luminescent materials. [ABSTRACT FROM AUTHOR]

Herein we report a one‐pot approach for the functionalized carbazoles and β‐carbolines via Fischer indole/Pictet‐Spengler type reactions followed by diethyl azodicarboxylate (DEAD) mediated dehydrogenative aromatization using Deep Eutectic Solvent (N,N'‐Dimethyl urea and L‐tartaric acid combination) as reaction medium. This one‐pot method enables the synthesis of library of compounds of carbazoles and β‐carbolines with good to excellent yields in short reaction times. The developed method was extended for the copper‐mediated reaction to minimize the amounts of DEAD required. Also, the application of gram scale reaction and reusability of the DES (in both cases) is demonstrated efficiently. [ABSTRACT FROM AUTHOR]

Expanded azahelicenes, as heteroanalogues of helically chiral helicenes, hold significant potential for chiroptical materials. Nevertheless, their investigation and research have remained largely unexplored. Herein, we present the facile synthesis of a series of expanded azahelicenes NHn (n=1–5) consisting of 11, 19, 27, 35, and 43 fused rings, mainly by Suzuki coupling followed by Bi(OTf)3‐mediated cyclization of vinyl ethers. The structures of NH2, NH3 and NH4 were confirmed through X‐ray crystallography analysis, and their (P)‐ and (M)‐ enantiomers were also isolated with chiral high performance liquid chromatography. The enantiomers exhibit large absorption (abs) and luminescence (lum) dissymmetry factors, with |gabs|max=0.044; |glum|max=0.003 for NH2, |gabs|max=0.048; |glum|=0.014 for NH3, and |gabs|max=0.043; |glum|max=0.021 for NH4, which are superior to their respective all‐carbon analogues. [ABSTRACT FROM AUTHOR]

Doping has been proven to be a good way to regulate the optical and electrical properties of the active elements including both inorganic and organic materials. In this paper, the study demonstrates a bipolar doping strategy for an intrinsic charge‐transfer binary‐complex through the use of p‐ and n‐type dopants, which incorporate toward highly‐ordered ternary complexes. Benefitting from the good lattice matching and energy level tuning, the supramolecular system with a large doping concentration range (0 ≤ x ≤ 50% or 40%) assembles into the original crystal lattice and exhibits tunable luminescence or quenching phenomena even at very low ratio. The 7h‐benzo[c]carbazole (BCZ) dopped cocrystals show yellow–green to red emission due to the Förster resonance energy transfer (FRET); while only 5% 7,7,8,8‐tetracyanoquinodimethane (TCNQ) dopant can bring superior photothermal (PT) behavior with a high PT conversion efficiency up to 75.3%, owing to the efficient non‐radiative decay way contribution. It is believed that the strong π–π interactions and free rotation of −C(C≡N)2 promote this decay way transition. This work on the charge‐transfer complex doping system suggests the great potential in optical, photothermal imaging, and therapy applications as well as information memory and photo sensing. [ABSTRACT FROM AUTHOR]

Formamidinium lead iodide (FAPbI3) represents an optimal absorber material in perovskite solar cells (PSCs), while the application of FAPbI3 in inverted‐structured PSCs has yet to be successful, mainly owing to its inferior film‐forming on hydrophobic or defective hole‐transporting substrates. Herein, we report a substantial improvement of FAPbI3‐based inverted PSCs, which is realized by a multifunctional amphiphilic molecular hole‐transporter, (2‐(4‐(10H‐phenothiazin‐10‐yl)phenyl)‐1‐cyanovinyl)phosphonic acid (PTZ−CPA). The phenothiazine (PTZ) based PTZ−CPA, carrying a cyanovinyl phosphonic acid (CPA) group, forms a superwetting hole‐selective underlayer that enables facile deposition of high‐quality FAPbI3 thin films. Compared to a previously established carbazole‐based hole‐selective material (2‐(3,6‐dimethoxy‐9H‐carbazol‐9‐yl)ethyl)phosphonic acid (MeO−2PACz), the crystallinity of FAPbI3 is enhanced and the electronic defects are passivated by the PTZ−CPA more effectively, resulting in remarkable increases in photoluminescence quantum yield (four‐fold) and Shockley‐Read‐Hall lifetime (eight‐fold). Moreover, the PTZ−CPA shows a larger molecular dipole moment and improved energy level alignment with FAPbI3, benefiting the interfacial hole‐collection. Consequently, FAPbI3‐based inverted PSCs achieve an unprecedented efficiency of 25.35 % under simulated air mass 1.5 (AM1.5) sunlight. The PTZ−CPA based device shows commendable long‐term stability, maintaining over 90 % of its initial efficiency after continuous operation at 40 °C for 2000 hours. [ABSTRACT FROM AUTHOR]

Carbazole‐incorporated smaragdyrin BF2‐complex 3 was synthesized by SNAr reaction of 3,5‐dibromo‐8‐mesityl‐BODIPY 1 with 3,6‐di(tert‐butyl)‐1,8‐di(pyrrol‐2‐yl)carbazole 2 as a nucleophile. Demetalation of 3 with ZrCl4 gave the corresponding smaragdyrin free base 4 in a good yield. Oxidations of 3 and 4 with MnO2 gave smaragdyrins 5 and 6, respectively, both followed by aromaticity switching, since the oxidized products showed a moderate paratropic ring current owing to their 20π‐electronic circuits. Further, treatment of 4 with [RhCl(CO)2]2 in the presence of NaOAc gave RhI complex 7, and oxidation of 3 with RuCl3 in the presence of triethylamine led to the formation of a spiro dimer product, 8. [ABSTRACT FROM AUTHOR]

The scopes of synthesis methods of porous polycarbazole materials are still under continuous developments because the polycarbazole materials with high stability and excellent porosity are suitable for various advanced applications. Here, ionothermal synthesis method for preparing porous polycarbazole materials is reported for the first time, by which a series of polycarbazole materials with good porosity and high yield are synthesized. Thereinto, the ferric chloride plays the roles of catalyst and molten solvent for preparing porous polycarbazole materials. The transformation of the pore structure due to slight carbonization during the process of ionothermal synthesis shows profound impacts on application performances. As intercomparison among these polymers, some porous polycarbazole materials with the predominant micropores possess a good performance of carbon dioxide uptake, others with micro‐mesopore structures show a high capacity of electrochemical energy storage. This simple and practicable method provides a pathway for synthesizing novel porous polycarbazole materials and similar porous organic polymers. [ABSTRACT FROM AUTHOR]

The prevalence of the D–A strategy in achieving red-shifted emission has been established through designing D–A molecules of D–A–D and A–D–A constructs. Architectural control over such D–A systems integrates solid state NIR emission with lysosome tracking and sets a multifarious goal of photophysical modulation in a comprehensive way. In particular, two compounds, CPM–1 (D–A–D) and CPM–2 (A–D–A), have been synthesized by introducing carbazole-based donors and difluoroboron acceptors. Lysosome targeting and imaging have been achieved through incorporation of a morpholine unit, which ultimately imparts viscosity sensitivity to the construct. The fluorophores exhibited significant emission in solution along with distinctive solvatochromism, viscochromism and TICT. A comparative account of these competitive photophysical properties revealed the superior charge transfer properties of the A–D–A construct (CPM–2), while the D–A–D molecule (CPM–1) was found to be a better molecular rotor with marked viscochromism. The solid state NIR emission has been found to be much more intense in CPM–1 relative to CPM–2, which further highlights the influence of structural aspects on photophysical behvaiour. Theoretical studies further established the distinctive characteristics of ground and excited states in these compounds. Owing to its excellent viscochromic behvaiour, CPM–1 has been successfully utilized in lysosome targeting in wild-type Drosophila fly gut tissues through co-localization studies. [ABSTRACT FROM AUTHOR]

Organic photosensitizers (PSs) with aggregation‐induced emission (AIE) characteristics have shown several advantages in photodynamic therapy (PDT). However, how to design PSs with the required optical and biological properties is a formidable challenge. In this work, a series of AIE active pyridine‐ and pyridinium‐functionalized carbazole with different substituents are designed and synthesized. Compared to other analogs, BK‐Pys‐BP containing benzophenone moiety on the pyridinium unit produces reactive oxygen species (ROS) efficiently in the presence of light due to its large spin‐orbit coupling constant to promote efficient intersystem crossing. Based on its structure, three molecules with enhanced donor–acceptor strength and conjugation are further investigated to realize emission covering the whole visible region. The cationic nature and excellent ROS generation ability of benzophenone‐containing AIE photosensitizers allows for specific imaging of mitochondria, killing cancer cells, and as a singlet oxygen donor to catalyze the formation of endoperoxides. Thus, the present work presents an effective strategy for creating AIE photosensitizers with efficient ROS generation for wide biological applications. [ABSTRACT FROM AUTHOR]

Six novel carbazole-based hole-transporting materials (HTMs) (DBC1–DBC6) have been meticulously engineered through structural modifications of the reference molecule R. These tailored molecules were designed by introducing thiophene-bridged and end-capped acceptor groups. A comprehensive analysis of critical characteristics, including frontier molecular orbitals (FMO), density of states (DOS), dipole moment (µ), optical properties, reorganization energy of holes and electrons (λ h , λ e) , open-circuit voltage ( V oc ), and fill factor (FF), was conducted using DFT and TD-DFT methods to assess their photovoltaic potential. Comparing the energy levels of the reference and designed molecules reveals their suitability as efficient hole transport materials for application in perovskite solar cells (PSCs). These engineered molecules have a lower-energy HOMO, a reduced energy gap (from 2.99 to 2.02 eV), and this change is associated with an improvement in hole mobility. All newly molecules (DBC1–DBC6) manifest higher absorption maxima ( λ max ) in the solvent (dichloromethane), up to 524 nm, surpassing the reference R (408 nm). This signifies superior light absorption properties and efficient hole transfer in the designed molecules. Furthermore, the hole reorganization energy λ h (from 0.112 to 0.850 eV) demonstrates improved hole mobility and reduced recombination losses compared to the R molecule. The designed HTMs exhibit substantial improvements in terms of energy conversion efficiency PCE (from 26.83 to 30.53%) and open-circuit voltage (from 1.20 to 1.35 V). These results underscore the feasibility of the proposed approach, paving the way for the production of solar cells with enhanced photovoltaic properties. [ABSTRACT FROM AUTHOR]

The object of research is newly synthesized carbazole-derived compounds and organic light-emitting structures based on them. The problem lies in the complex solution of scientific and technical problems of improving the characteristics and stability of organic light-emitting diodes (OLEDs), namely improving the brightness and energyefficient parameters. Organic light-emitting structures of blue, blue, and green radiation with color coordinates were formed by the thermovacuum sputtering method and the solution deposition method. The turn-on voltage of the white OLED is 6 V, the maximum brightness of the light-emitting structures was 10,000 cd/m². The devices demonstrated a sufficiently high external quantum efficiency of 5 % to 7 %. This paper reports the multifunctional application of a simple donor-acceptor organic compound, as active and host material in the emission layer of organic light emitting devices. Em1 has been used as active components in OLEDs, where Em1 is the guest emitter (Device A), the acceptor part of the excited emitter (Device B) and the host matrix of the CdSeS/ZnS alloy quantum dot (at least four different OLEDs have been designed and characterized where Em1 plays the role of the guest emitter (Device C). The external quantum efficiencies of devices A–C are characterized by values common to pure fluorescent OLEDs (up to 5 % of the theoretical limit), but these devices sustain low-efficiency roll-off of electroluminescence over a wide range of current densities. Organic light-emitting diodes based on carbazole-derived compounds, due to their color characteristics, are promising candidates for use in the latest lighting systems. A separate advantage of the data light-emitting structures is a multifunctional application of one compound for different types of light-emitting structures. In addition, organic LEDs on based on carbazole-derived compounds have low energy consumption and are environmentally friendly due to the absence of toxic substances in their architecture, which creates prerequisites for saving energy resources and reducing the industrial burden on the environment. [ABSTRACT FROM AUTHOR]

This research investigates characterization of low lying excitations of newly designed organic dyes for their local excited and charge transfer-related molecular switching attributes such as donor-acceptor relations against the carbazole bridge. The eight new dyes, having 4 symmetrical (Syn-A-D) and 4 antisymmetric (Anti-A-D) arrangements showed how the push-pull effect can operate to create the charge transfer phenomenon. Their absorption energies (E) for Syn dyes ranged from 2.98 eV to 4.07 eV, with corresponding wavelengths (λmax) ranging from 304 nm to 415 nm. While for their Anti arrangements, it ranged from 1.62 eV to 3.99 eV, with corresponding λmax values as 310-617 nm. Syn-C1 with an ionization potential (IP) of 6.59 eV and an electron affinity (EA) of 2.04 eV can be predicted to be more chemically stable compared to Anti-C2 with an IP of 5.16 eV and an EA of 3.86 eV. Syn-C also has the highest Voc (3.24 eV) and Pmax (22.35 W), indicating that it has the potential to be more chemically stable as compared to the other dyes. The findings of this research contributed to a better understanding of the molecular switching attributes of carbazole-based organic dyes, which could have implications for various applications, including optoelectronics and energy conversion devices. This research explores on characterizing low lying excitations of newly designed organic dyes for their local excited and charge transfer related molecular switching attributes as donor-acceptor relations against the carbazole bridge. The eight new dyes, having 4 symmetrical (Syn-A-D) and 4 antisymmetric (Anti-A-D) arrangements showed that how the push-pull effect can operate to create the charge transfer phenomenon. [ABSTRACT FROM AUTHOR]

Inverted organic light-emitting devices (OLEDs) have been aggressively developed because of their superiorities such as their high stability, low driving voltage, and low drop of brightness in display applications. The injection of electrons is a critical issue in inverted OLEDs because the ITO cathode has an overly high work function in injecting electrons into the emission layer from the cathode. We synthesized hexagonal wurtzite ZnO nanoparticles using different oxidizing agents for an efficient injection of electrons in the inverted OLEDs. Potassium hydroxide (KOH) and tetramethylammonium hydroxide pentahydrate (TMAH) were used as oxidizing agents for synthesizing ZnO nanoparticles. The band gap, surface defects, surface morphology, surface roughness, and electrical resistivity of the nanoparticles were investigated. The inverted devices with phosphorescent molecules were prepared using the synthesized nanoparticles. The inverted devices with ZnO nanoparticles using TMAH exhibited a lower driving voltage, lower leakage current, and higher maximum external quantum efficiency. The devices with TMAH-based ZnO nanoparticles exhibited the maximum external quantum efficiency of 19.1%. [ABSTRACT FROM AUTHOR]

A novel series of some 2-[(9-ethyl-9H-carbazol-3-yl)imino]thiazoles/thiazolidinones was synthesized and established by spectroscopic tools and elemental analysis. The synthetic strategy depended on cyclization of 1-(9-ethyl-9H-carbazol-3-yl)-3-phenylthiourea (2) with different α-halocarbonyl compounds and some carbon electrophiles under mild reaction conditions. All products were screened for their in vitro cytotoxic activities toward three human cancer cell lines (MCF-7, HepG-2 and HCT-116). Interestingly, the particular carbazolyl derivatives 7, 13, 14 and 16 exhibited promising cytotoxicity results against all the evaluated cell lines. Also, molecular docking studies for the highly bioactive compounds were achieved to investigate the binding mode toward (VEGFR-2-KDR) receptor. Moreover, anticancer results were validated computationally by applying SwissADME server. [ABSTRACT FROM AUTHOR]

The alkaloid carbazole is one of the relevant structural motifs in drug discovery. Indeed, carbazoles have been largely investigated for their various biological properties. In this article, in order to ensure the possibility of carrying out the carbazole N-alkylation synthesis reaction at the synthesis laboratory level and to gain access to a new active biomolecule, we present the theoretical study of strategies for the synthesis of an N-alkylcarbazole using the DFT method at B3LYP, with the basis set 6-31G(d,p). In fact, this research has enabled us to establish a simple, economic, and efficient synthesis strategy for this nitrogenous heterocycle with an excellent yield, by N-alkylation between carbazole and propargyl bromide under different experimental conditions. We have developed an environmentally respectful synthesis process, a gentle packaging protocol and a practical procedure for the preparation of this polycyclic aromatic compound. The structure of the synthesized compound was determined by spectroscopic methods: 1H-NMR, 13C-NMR, and MS data. The theoretical results corroborate with experiences. The study of the substitution effect on the optical properties of reagents and products shows that N-alkylation has an influence on the optical properties. [ABSTRACT FROM AUTHOR]

The halogen substitution in an organic fluorophore exerted significant influence on the molecular organization via halogen intermolecular interactions and solid-state fluorescence. The carbazole core unit has been extensively utilized for developing optoelectronic materials because of its excellent fluorescence and phosphorescence properties. Herein, we have synthesized dihalogen substituted carbazoles (Cz-Cl, Cz-Br, Cz-I) and investigated their role in the supramolecular organization and solid-state fluorescence. Solid-state structural analysis revealed that Cz and halogen derivatives produced a herringbone structure but with varied intermolecular interactions and molecular orientation. Cz showed N–H⋯π intermolecular interactions between the amine hydrogen and middle ring of carbazole. Cz-Cl and Cz-Br also showed N–H⋯π intermolecular interactions but between the amine hydrogen and halogen decorated phenyl ring of carbazole. Cz-I showed only weak halogen–halogen and halogen–hydrogen intermolecular interactions. Cz showed strong fluorescence in solution as well as the solid-state (Φf = 55.9%). However, halogen substituted carbazole derivatives showed only solid-state fluorescence with strong reduction of fluorescence efficiency (Φf = 6.5% (Cz-Cl), 1.2% (Cz-Br)). Further, Cz-I did not show any fluorescence even in the solid-state. The significant reduction of fluorescence might be attributed to the heavy atom effect. Halogen substitution also caused varied electron density distribution in the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO). Thus, halogen substitution influenced the molecular organization via halogen intermolecular interactions and solid-state fluorescence due to the heavy atom effect. [ABSTRACT FROM AUTHOR]

Effective passivation of defects at the buried interface between the perovskite absorber and hole‐selective layer (HSL) is crucial for achieving high performance in inverted perovskite solar cells (PSCs). Additionally, the HSL needs to possess compact molecular packing and intrinsic photo‐ and thermo‐stability to ensure long‐term operation of the devices. In this study, a novel MeO‐BTBT‐based self‐assembled monolayer (SAM) is reported to serve as an efficient HSL in inverted PSCs. Compared to the well‐established carbazole‐containing SAM MeO‐2PACz, MeO‐BTBT has flat and more extended conjugation with large atomic radius of the sulfur atom. These induce stronger intermolecular interactions to enable more ordered and compact SAM to be formed on indium–tin oxide (ITO) substrates. Meanwhile, the sulfur atoms in MeO‐BTBT can coordinate with Pb2+ ions to passivate the defects at the buried interface of perovskite absorber. The derived perovskite films show both high photoluminescence (PL) quantum yield (13.2%) and a long lifetime (7.2 µs). The PSCs based on MeO‐BTBT show a PCE of 24.53% with an impressive fill factor of 85.3%. The PCEs of MeO‐BTBT‐based devices can maintain ≈95% of their initial values after being aged at 65 °C for more than 1000 h or continuous operation under 1‐sun illumination. [ABSTRACT FROM AUTHOR]

The catalytic conversion of lignin into heterocyclic aromatic compounds holds significant promise not only for expanding lignin's utility in pharmaceutical synthesis but also for imparting luminescent properties to downstream lignin products. However, the challenge lies in devising compatible catalytic conditions for selectively cleaving aromatic ether bonds and forming C–N bonds. In this study, we present a new approach to synthesizing functionalized carbazole derivatives from lignin phenolic β-O-4 model linkages using a one-pot, two-step method. Through a [3 + 1 + 2] benzene cyclization reaction involving lignin β-O-4 model compound, indole-3-carbaldehyde, and 3-chloropropiophenone catalyzed by cost-effective CuCl2·2H2O, we achieved yields of carbazole derivatives up to 90%, highlighting the economic viability of our approach. Our protocol is versatile, accommodating various reaction conditions, including selective cleavage of the C–O bond, aldol condensation, dehydrochlorination of β-chloro ketones, Diels–Alder addition, and dehydroaromatization reactions. Additionally, the resulting carbazole derivatives exhibit favorable twisted-intramolecular charge transfer (TICT) and aggregation-induced emission (AIE) effects. This method offers a sustainable and practical strategy for synthesizing lignin-based carbazoles, with economic advantages in terms of the catalysts and precursors, thereby advancing lignin's application in luminescent materials. [ABSTRACT FROM AUTHOR]

Herein, we describe a copper‐catalyzed sequential C(sp2)−H/C(sp3)−H annulation of indoles with propargylic alcohols for the synthesis of diversely functionalized hydrobenzo[b]carbazole scaffolds. The reaction involves a Friedel‐Crafts addition, 1,5‐H shift, 6π electrocyclization, and dearomatization‐aromatization cascade. Importantly, this is a report of the use of 2‐(diarylmethyl)indoles as three‐carbon synthons in a (3+3) annulation reaction involving C(sp3)−H indole functionalization under oxidant‐free conditions. [ABSTRACT FROM AUTHOR]

A cascade reaction between 2‐styrylbenzaldehydes and indoles has been developed for the synthesis of 1H‐indenes. An iodine‐catalyzed nucleophilic addition of indoles to an aldehyde group of 2‐styrylbenzaldehydes leads to the formation of carbocation intermediates that undergo 4π‐electrocyclization to give indenes with a trisubstituted double bond. These indenes are transformed into thermodynamically more stable products with a fully substituted double bond under the reaction conditions. Minor quantities of indolylbenzo[b]carbazoles are also produced as by‐products. [ABSTRACT FROM AUTHOR]

Three sulfonate‐containing polyelectrolytes are elaborately designed and used to passivate perovskite film with the anti‐solvent method. Under the influence of the secondary monomer, three copolymers present various chemical configurations and deliver different modification effects. Fluorene‐thiophene copolymer STF has linear and highly‐conjugated chain. STF‐perovskite film presents large crystal grains. Fluorene‐carbazole copolymer SCF has flexible chain and easily enters into grain boundary areas. SCF‐perovskite film is homogenous and continuous. Fluorene‐fluorene copolymer SPF agglomerates on the surface and is not applicable to the anti‐solvent method. The full investigation demonstrates that STF and SCF not only conduct surface defect passivation, but also improve the film quality by being involved in the perovskite's crystallization process. Compared with the control device, the devices with STF and SCF deliver high efficiency and excellent stability. The unencapsulated devices with STF and SCT maintain ≈80% of the initial power conversion efficiency (PCE) after 40 days of storage under 30–40% relative humidity. SCF performs better and the device maintains 60% of the initial PCE after 20 days of storage under 60–80% relative humidity. [ABSTRACT FROM AUTHOR]

Distyrylbenzenes (DSBs) are well‐known for their strong multicolour fluorescence. Fluorescence tuning of DSB via further functionalization/arylation, on the other hand, is uncommon. This paper reports a Pd‐catalysed direct arylation approach for introducing different aryl groups onto fluorobenzene‐containing DSB moiety (7) in high yields (67–72 %). The versatile methodology allows the substitution of neutral [tolyl (1)], electron‐deficient [p‐formyl benzene (2), p‐acetyl benzene (3), p‐nitrobenzene (4)] and electron‐rich [carbazole (5), triphenylamine (6)] aryl groups. The electron‐deficient aryls render mono‐substitution, while the electron‐rich counterparts promote di‐substitution. The compounds (1–6) show blue, green, and yellow fluorescence in both the solution and solid states; the fluorescence quantum yields reach >98 % and the peak maxima span from 425 to 560 nm. The mono‐carbazole DSB (5) exhibit white light emission (WLM) in polar solvents (acetone, DMF, CH3CN, DMSO and NMP) with very high fluorescence quantum yields (φf) of 60–80 %. For WLM, such high efficiency (φf) is somewhat uncommon. Moreover, visible‐to‐NIR reversible electrochromism is demonstrated by the TPA‐integrated DSB (6). The colour of 6 changes from pristine light yellow to orange, and the absorption maxima shifts from 372 to 1500 nm when a positive potential of 1.0 V vs Ag/Ag+ is applied. Moreover, the system shows high colouration efficiency in the NIR region with fast switching speeds for colouration and decolouration as fast as 0.98 s and 1.05 s. [ABSTRACT FROM AUTHOR]

This review centers on the synthetic strategies employed with indolyl‐ynones. Indolyl‐ynone, owing to its highly reactive ynone moiety, frequently partakes in dearomatizing spirocyclization reactions and subsequent rearrangement reactions when subjected to various reaction conditions. Hence, various heterocycles such as densely functionalized spiroindolenines, carbazoles, quinolines and carbo‐and hetero‐cycle substituted indoles are synthesized from indolyl‐ynones. In addition to this, the versatile spirocyclic indole scaffold exhibits the capability to produce tetracyclic and polyclic structures through intricate skeletal rearrangement processes. Moreover, the total synthesis of natural products using the indolyl‐ynone moiety was also compiled in this review. [ABSTRACT FROM AUTHOR]

Carbazole derivatives can be used as antioxidants in the lubricating oil industry. The alkylation of carbazole with 2-chloro-2-methylpropane and 2-bromopropane catalyzed by anhydrous aluminum chloride was studied. Initially, 3,6-di-iso-propylcarbazole and 3,6-di-tert-butylcarbazole were using dichloromethane and dibromomethane as solvents at room temperature, respectively. The synthesis conditions were optimized. Subsequently, the effects of reaction time, catalyst dosage, and molar ratio of carbazole to alkylating agent were investigated, and orthogonal experiments were performed. The structures of the carbazole derivatives were characterized by Fourier infrared spectroscopy (FT-IR), mass spectrum (MS) and nuclear magnetic resonance spectroscopy (NMR). The thermal stability of the synthesized carbazole derivatives was investigated by differential scanning calorimetry (DSC). The carbazole derivatives were added into the lubricating oil with a mass fraction of 0.8% and the miscibility, stability and oxidation resistance of the mixed system were evaluated by mechanical stirring and a rotary pressure vessel oxidation test (RPVOT). The DSC results showed that there was good thermal stability for the carbazole derivatives. The mechanical stirring method revealed good solubility and stability for the mixture of oil and carbazole derivatives. The RPVOT results showed that isopropyl carbazole derivatives could increase the oxidation induction period of lubricating oil to 1.39 times, and tert-butyl carbazole derivatives could increase the oxidation induction period of lubricating oil to 1.91 times. The antioxidant effect of tert-butyl carbazole derivatives was better than that of isopropyl carbazole derivatives. [ABSTRACT FROM AUTHOR]

Carbazole derivatives are widely used to make highly efficient optoelectronic materials. In this context, we developed a method for synthesizing conjugated carbazole derivatives using bimetallic Pd–Cu nanoparticles (NPs) immobilized on reduced graphene oxide (rGO) sheets. Pd–Cu NPs were synthesised in a one-pot wet chemical process with ascorbic acid as the reducing agent. The Pd–Cu NPs have an average diameter of 3.8 ± 1.2 nm. X-ray diffraction, SEM, TEM, EDS, and cyclic voltammetry were used to characterise the structure and morphology of the Pd–Cu@rGO NPs. N-Protected-3-aryl/heteroaryl carbazoles were efficiently synthesized using the Pd–Cu@rGO catalyst, which enabled the Suzuki–Miyaura (SM) cross-coupling reaction between N-protected-3-bromo-carbazoles and a range of aryl/heteroaryl boronic acids. The prepared compounds were characterized by NMR (1H & 13C) and HRMS spectra. For the SM reaction, the catalytic performance of the monometallic Pd@rGO and bimetallic Pd–Ni@rGO and Pd–Cu@rGO catalysts were studied with various metal loadings. In comparison to the monometallic Pd@rGO and bimetallic Pd–Ni@rGO catalysts, the bimetallic Pd–Cu@rGO heterogeneous catalyst (L3) demonstrated improved catalytic performance with yields of up to 98%. The material exhibits excellent recyclability and can be reused up to five times without experiencing any decline in its effectiveness. The electronic structure modification offered by the Pd–Cu ensemble on rGO may be responsible for its higher catalytic efficiency. UV and fluorescence spectra were used to investigate the optoelectronic properties of the produced carbazole compounds. Among the compounds studied, 5f, 5n, and 5h exhibited superior UV absorption and fluorescence emission due to the presence of auxochromes and extended conjugation. This study explores the efficacies of the reduced graphene oxide-supported Pd–Cu bimetallic system with different weight% for milder SM reactions. [ABSTRACT FROM AUTHOR]

Herein, we report a fluorene-bridged double carbonyl/amine-based MR TADF emitter DDiKTa-F, formed by locking the conformation of the previously reported compound DDiKTa. Using this strategy, DDiKTa-F exhibited narrower, brighter, and red-shifted emission. The OLEDs with DDiKTa-F emitted at 493 nm and showed an EQEmax of 15.3% with an efficiency roll-off of 35% at 100 cd m−2. [ABSTRACT FROM AUTHOR]

Simple Summary: Weaning stress is a major problem in the pig industry, causing high rates of diarrhea and poor performance in piglets. Cardamonin is a bioactive plant extract that possesses anti-inflammatory, anti-oxidant, and anti-viral properties. In this experiment, we investigated the effect of Cardamonin on intestinal barrier damage and inflammatory response caused by immune stress in piglets by establishing a stress model of LPS. Compared with those of the LPS group, the intestinal mucosal morphology and expression of tight junction proteins in the cardamonin group were improved, along with the inflammation response. Furthermore, certain intestinal microbiota and inflammation-related metabolites showed a significant correlation. The results indicate that the administration of Cardamonin can effectively improve intestinal mucosal barrier damage and inflammatory response induced by LPS by regulating the composition and metabolism of intestinal microbiota, with a better effect observed at a dosage of 6 mg/kg. The primary factor leading to elevated rates of diarrhea and decreased performance in piglets is immunological stress. The regulation of immune stress through the intestinal flora is a crucial mechanism to consider. In total, 30 weaned piglets were randomly allocated to five groups: the basal diet group (Control), basal diet + lipopolysaccharides group (LPS), basal diet + 250 μg/kg 6-Formylindolo [3,2-b] carbazole + LPS group (FICZ), basal diet + 3mg/kg Cardamonin + LPS group (LCDN), and basal diet + 6mg/kg Cardamonin + LPS group (HCDN/CDN). The results showed that compared with those of the LPS group, the expression of tight junction proteins (occludin; claudin-1) in the FICZ group was significantly increased, and the mRNA levels of IL-1β and TNF-α were significantly reduced (p < 0.05). HCDN treatment had a better effect on LPS-induced intestinal barrier damage in this group than it did in the LCDN group. HCDN treatment leads to a higher villus height (VH), a higher ratio of villi height to crypt depth (V/C), higher tight junction proteins (ZO-1; occludin), and higher short-chain fatty acids (SCFAs). In addition, correlation analyses showed that Succinivibrio was positively correlated with several SCFAs and negatively correlated with prostaglandin-related derivatives in the FICZ group and CDN group (p < 0.05). In summary, Cardamonin alleviates intestinal mucosal barrier damage and inflammatory responses by regulating the intestinal microbiota and its metabolism. [ABSTRACT FROM AUTHOR]

A new carbazole-coupled tetrakis-(1 H-pyrrole-2-carbaldehyde) anion receptor 1 has been designed and synthesized. Anion binding studies in organic media using fluorescence and UV-vis spectroscopy revealed that receptor 1 is capable of sensing HP2O73- with high selectivity. Addition of HP2O73- to THF solution of 1 resulted in the emergence of a new broad band at longer wavelength along with quenching of the original emission band forming a ratiometric response. Based on dynamic light scattering (DLS) experiment and fluorescence lifetime measurement, we propose that the emergence of new emission band in the presence of HP2O73- ion is due to the aggregation-induced excimer formation. [ABSTRACT FROM AUTHOR]

Streptocarbazoles are a class of indolocarbazole (ICZ) compounds produced by Streptomyces strains that feature unique cyclic N-glycosidic linkages between the 1,3-carbon atoms of the glycosyl moiety and the two indole nitrogen atoms. Although several streptocarbazole compounds display effective cytotoxic activity, their biosynthesis remains unclear. Herein, through the inactivation of the aminotransferase gene spcI in the staurosporine biosynthetic gene cluster spc followed by heterologous expression, two new streptocarbazole derivatives (1 and 3) and three known ICZs (2, 4, and 5) were generated. Their structures were determined by a combination of spectroscopic methods, circular dichroism measurements, and single-crystal X-ray diffraction. Compounds 1–4 displayed moderate cytotoxicity against HCT-116 cell line, and compounds 3 and 4 were effective against Huh 7 cell line. Double-gene knockout experiments allowed us to propose a biosynthetic pathway for streptocarbazole productions. Furthermore, by overexpression of the involving key enzymes, the production of streptocarbazoles 1 and 3 were improved by approximately 1.5–2.5 fold. IMPORTANCE Indolocarbazoles (ICZs) are a group of antitumor agents, with several analogs used in clinical trials. Therefore, the identification of novel ICZ compounds is important for drug discovery. Streptocarbazoles harbor unique N-glycosidic linkages (N13-C1′ and N12-C3′), distinguishing them from the representative ICZ compound staurosporine; however, their biosynthesis remains unclear. In this study, two new streptocarbazoles (1 and 3) with cytotoxic activities were obtained by manipulating the staurosporine biosynthetic gene cluster spc followed by heterologous expression. The biosynthetic pathway of streptocarbazoles was proposed, and their productions were improved through the overexpression of the key enzymes involved. This study enriches the structural diversity of ICZ compounds and would facilitate the discovery of new streptocarbazoles via synthetic biological strategies. [ABSTRACT FROM AUTHOR]

The rapid detection of Ni ions has important research and application value. This paper presents a novel specific turn-off fluorescence probe PCTMP-FS for detecting Ni2+ ions. The carbazole-based compound PCTMP is first synthesized via a two-step reaction. PCTMP-FS comprises PCTMP dispersed into a DMSO-H2O (fw = 30% v/v) mixed solvent. The probe demonstrates prominent selectivity and anti-interference abilities for detecting Ni2+ with a limit of detection (LOD) of 0.233 μM. The probe exhibits good applicability over a wide range of acidities. The detecting mechanism of the probe is due to the complex formed by PCTMP and Ni2+ (2:1), which destroys intramolecular charge transfer in the compound. The probe has good repeatability and demonstrates excellent stability and sensitivity for the detection of Ni2+ in real water samples. [ABSTRACT FROM AUTHOR]

Carbazole polymers attract significant attention as promising luminophores, organic electronic and photovoltaic materials, photo/electrocatalysts, energy storage materials, redox mediators and catalysts. However, the oxidation potential of the commercially available poly(vinylcarbazole) is insufficient for some applications such as high-voltage Li-Ion batteries. We have proposed a monomer for the novel polycarbazole with an increased oxidation potential, which will be compatible with high-voltage cathode materials for Li-Ion. In addition, the proposed polymer is an interesting substrate for the further carbonization to obtain N-doped carbons with a high electrocatalytic activity level. [ABSTRACT FROM AUTHOR]

Stille coupling between 5,5′-dibromo-4,4′-diphenyl-2,2′-bithiazole and 9-(2-ethylhexyl)-3-(tributylstannyl)-9H-carbazole in the presence of Pd(Ph3P)2Cl2 in toluene, heated at reflux for 2 h, gave 5,5′-bis[9-(2-ethylhexyl)-9H-carbazol-3-yl]-4,4′-diphenyl-2,2′-bithiazole in 85% yield. [ABSTRACT FROM AUTHOR]

Alectinib hydrochloride is an anticancer medication used for the first-line treatment of non-small cell lung cancer. Although it was approved for medical use ten years ago, and three polymorphs of this substance were proposed based on X-ray diffraction patterns, their crystal structures remained unknown to date. The main problem was the preparation of high quality single crystals due to the very low solubility of the salt. Herein, we report on the molecular and crystal structure of form I of alectinib hydrochloride as obtained using powder X-ray diffraction data from a laboratory source. Short Cl...N distances between the anion and the nitrogen atoms of the morpholine and benzo[b]carbazole rings indicate the positions of the H(N) atoms. As a result, the cation and anion form infinite Cl...H(N)-bonded chains. [ABSTRACT FROM AUTHOR]