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Life on Earth uses DNA as the central template for self‐replication, genetic encoding, and information transfer. However, there are no physical laws precluding life's existence elsewhere in space, and alternative life forms may not need DNA. In the search for exobiology, knowing what to look for as a biosignature remains a challenge – especially if it is not from the obvious list of biologic building blocks. Clues from chemicals recently discovered on Mars and in the Taurus Molecular Cloud 1 (TMC‐1), show that intriguing organic compounds exist beyond Earth, which could provide a starting point for unconventional exobiotic designs. Here we present a new potential self‐replicating system with structural similarities to recently discovered compounds on Mars and TMC‐1. Rather than using DNA's hydrogen‐bonding motif for reliable base‐paring, our design employs sulfur‐nitrogen interactions to selectively template unique benzothiadiazole units in sequence. We synthesized and studied two versions of this system, one reversible and the other irreversible, and found experimental evidence of self‐replication in d‐chloroform solvent. These results are part of a larger pursuit in our lab for developing a basis for a potential exobiological system using starting blocks closely related to these cosmic compounds. [ABSTRACT FROM AUTHOR]

Near‐infrared (NIR) absorbing electron donor‐acceptor (D−A) chromophores have been at the forefront of current energy research owing to their facile charge transfer (CT) characteristics, which are primitive for photovoltaic applications. Herein, we have designed and developed a new set of benzothiadiazole (BTD)‐based tetracyanobutadiene (TCBD)/dicyanoquinodimethane (DCNQ)‐embedded multimodular D−A systems (BTD1‐BTD6) and investigated their inherent photo‐electro‐chemical responses for the first time having identical and mixed terminal donors of variable donicity. Apart from poor luminescence, the appearance of broad low‐lying optical transitions extendable even in the NIR region (>1000 nm), particularly in the presence of the auxiliary acceptors, are indicative of underlying nonradiative excited state processes leading to robust intramolecular CT and subsequent charge separation (CS) processes in these D−A constructs. While electrochemical studies identify the moieties involved in these photo‐events, orbital delocalization and consequent evidence for the low‐energy CT transitions have been achieved from theoretical calculations. Finally, the spectral and temporal responses of different photoproducts are obtained from femtosecond transient absorption studies, which, coupled with spectroelectrochemical data, identify broad NIR signals as CS states of the compounds. All the systems are found to be susceptible to ultrafast (~ps) CT and CS before carrier recombination to the ground state, which is, however, significantly facilitated after incorporation of the secondary TCBD/DCNQ acceptors, leading to faster and thus efficient CT processes, particularly in polar solvents. These findings, including facile CT/CS and broad and intense panchromatic absorption over a wide window of the electromagnetic spectrum, are likely to expand the horizons of BTD‐based multimodular CT systems to revolutionize the realm of solar energy conversion and associated photonic applications. [ABSTRACT FROM AUTHOR]

We present a novel synthetic route for the rapid construction of dithieno[3′,2′:3,4;2′′,3′′:5,6]benzo[1,2‐c][1,2,5]thiadiazoles via Na2S‐promoted thiophene annulation. This method facilitated the synthesis of D18−Cl polymer, known for its efficacy as a polymer donor in bulk‐heterojunction polymer solar cells. Starting from commercially available 4,7‐dihalo‐5,6‐difluorobenzo[c][1,2,5]thiadiazole, various 4,7‐dialkynylated compounds were obtained through Sonogashira reaction conditions. Subsequent Na2S‐promoted thiophene annulations yielded DTBT and its derivatives in excellent yields within 10 minutes. DTBT was then utilized as a precursor for the concise synthesis of D18−Cl, benefiting from reduced synthetic steps, mild reaction conditions, decreased complexity, and high overall yields. In another route, a space group‐bridged DTBT was directly constructed via Na2S‐promoted thiophene annulations and converted into D18−Cl through a couple of steps. This developed protocol offers a straightforward and reliable synthetic tool, conducive to reducing complexities in the production of DTBT‐based organic electronic materials, thereby advancing the potential commercialization of organic solar cells. [ABSTRACT FROM AUTHOR]

The exploration of novel functionalized supramolecular coordination complexes (SCCs) can enable new applications in domains that include purification and sensing. In this study, employing a coordination‐driven self‐assembly strategy, we designed and prepared a series of benzochalcogenodiazole‐based metallohelicates as high‐efficiency charge‐transfer surface‐enhanced Raman scattering (SERS) substrates, expanding the range of applications for these metallohelicates. Through structural modifications, including the substitution of single heteroatoms on ligands, replacement of coordinating metals, and alteration of ligand framework linkages, the Raman performance of these metallohelicates as substrates were systematically optimized. Notably, the SERS enhancement factors (EFs) of the metallohelicate‐based SERS substrates were significantly enhanced to levels as high as 1.03×107, which rivals the EFs of noble metals devoid of “hot spots”. Additionally, the underlying Raman enhancement mechanisms of these metallohelicates have been investigated through a combination of control experiments and theoretical calculations. This study not only demonstrates the utility of metallohelicates as SERS substrates but also offers insights and materials for the development of high‐efficiency new charge‐transfer SERS substrates. [ABSTRACT FROM AUTHOR]

N-(2-(diphenylphosphino)ethyl)-4,6,7-trifluoro-2,1,3-benzothiadiazol-5-amine (Ph2PCH2CH2NH-btd-F3 (PCCN)) is prepared by the reaction of 4,5,6,7-tetrafluoro-2,1,3-benzothiadiazole (btd-F4) with 2-(diphenylphosphino)ethyl-1-amine (Ph2PCH2CH2NH2) leading to the nucleophilic substitution of F– by a phosphinamide fragment (Ph2PCH2CH2NH)– in btd-F4. Phase 1 (a product of cocrystallization of PCCN (85%) and its oxide Ph2P(O)CH2CH2NH–btd-F3 (POCCN, 15%)) is obtained by the separation of the mixture of products by thin-layer chromatography and subsequent evaporation of the solution. POCCN is obtained preparatively using the oxidation of PCCN by hydrogen peroxide. Phase 1, two polymorphs of POCCN (2 and 4), and the POCCN·C6H6 solvatomorph (3) are characterized by XRD. The P–C–C–N fragment in these phases adopts either a bent gauche-conformation with an intramolecular N–H⋯O hydrogen bond or an anti-conformation stabilized by a pair of intermolecular hydrogen bonds combining the molecules into a dimer. According to the DFT data, gauche-POCCN has a larger negative electrostatic potential at F and N than anti-POCCN, i.e. the btd-F3 fragment of the first conformation is more likely to participate in predominantly electrostatic intermolecular interactions. [ABSTRACT FROM AUTHOR]

Disordered polymer chain entanglements within all‐polymer blends limit the formation of optimal donor‐acceptor phase separation. Therefore, developing effective methods to regulate morphology evolution is crucial for achieving optimal morphological features in all‐polymer organic solar cells (APSCs). In this study, two isomers, 4,5‐difluorobenzo‐c‐1,2,5‐thiadiazole (SF‐1) and 5,6‐difluorobenzo‐c‐1,2,5‐thiadiazole (SF‐2), were designed as solid additives based on the widely‐used electron‐deficient benzothiadiazole unit in nonfullerene acceptors. The incorporation of SF‐1 or SF‐2 into PM6 : PY‐DT blend induces stronger molecular packing via molecular interaction, leading to the formation of continuous interpenetrated networks with suitable phase‐separation and vertical distribution. Furthermore, after treatment with SF‐1 and SF‐2, the exciton diffusion lengths for PY‐DT films are extended to over 40 nm, favoring exciton diffusion and charge transport. The asymmetrical SF‐2, characterized by an enhanced dipole moment, increases the power conversion efficiency (PCE) of PM6 : PY‐DT‐based device to 18.83 % due to stronger electrostatic interactions. Moreover, a ternary device strategy boosts the PCE of SF‐2‐treated APSC to over 19 %. This work not only demonstrates one of the best performances of APSCs but also offers an effective approach to manipulate the morphology of all‐polymer blends using rational‐designed solid additives. [ABSTRACT FROM AUTHOR]

Herein, we report monomeric and dimeric norbornadiene‐quadricyclane molecular photoswitch systems intended for molecular solar thermal applications. A series of six new norbornadiene derivatives conjugated with benzothiadiazole as the acceptor unit and dithiafulvene as the donor unit were synthesized and fully characterized. The photoswitches were evaluated by experimentally and theoretically measuring optical absorption profiles and thermal conversion of quadricyclane to norbornadiene. Computational insight by density functional theory calculations at the M06‐2X/def2‐SVPD level of theory provided geometries, storage energies, UV‐vis absorption spectra, and HOMO‐LUMO levels that are used to describe the function of the molecular systems. The studied molecules exhibit absorption onset ranging from 416 nm to 595 nm due to a systemic change in their donor‐acceptor character. This approach was advantageous due to the introduction of benzothiadiazole and the dimeric nature of molecular structures. The best‐performing system has a half‐life of 3 days with quantum yields over 50 %. [ABSTRACT FROM AUTHOR]

Despite the wealth of studies on benzothiadiazole (BTH) and its capacity to modulate grape polyphenol metabolism, comprehensive data detailing polyphenol accumulation at various grape growth stages remain scarce. Therefore, the present study utilized pre-harvest (at 21 days after flowering) canopy-applied BTH (50 mg/L) on Cabernet Gernischt and Cabernet Franc grapes to investigate the physicochemical and polyphenolic changes during grape maturation. The results showed that BTH treatment significantly affected the accumulation of total phenols, flavonoids, flavanols, anthocyanins, and tannins. Concurrently, it induced an increase in colorimetric parameters (CIRG, L*, b*, a*, and C*ab), resulting in the treated grapes exhibiting a greater color intensity and enhanced red-bluish colorimetric characteristics. Moreover, the BTH treatment amplified the anthocyanin content in the grapes, with the levels of petunidin-3-O-glucoside and peonidin-3-O-glucoside exhibiting remarkable increases, particularly in the Cabernet Franc grape. Notably, the content of peonidin-3-O-glucoside even surpassed that of malvidin-3-O-glucoside throughout the growth stages, indicating significant advantages in the treated samples. Additionally, the levels of flavanol, flavonols, phenolic acids, and stilbenes experienced a significant boost post-treatment. In conclusion, the application of BTH treatment can effectively enhance the accumulation of polyphenols and intensify the color of Cabernet Gernischt and Cabernet Franc grapes, thereby significantly improving the overall quality of wine grapes and ensuring the production of higher-quality wines. The research findings will serve as a theoretical foundation and provide scientific data for the appropriate utilization of BTH in wine grape cultivation. [ABSTRACT FROM AUTHOR]

A homologous series of 4,7‐bis(aryl) substituted benzothiadiazole (BTD) compounds, containing the helicenic derivatives bis([4]helicene), bis([5]helicene) and bis([6]helicene), have been prepared upon a double Suzuki coupling between 3,6‐bis(pinacolyl‐borane)‐BTD and the corresponding bromo‐aryl precursors. The single crystal X‐ray structure of the bis([4]helicene) compound shows the existence of both helicities (M) and (P) on the same molecule. All the compounds of the series are highly emissive in solution, with quantum yields of the emission ranging from 50 to 91 %. The enantiopure compounds (M,M) and (P,P) for the BTD‐bis([6]helicene) have been prepared from the corresponding enantiopure 2‐bromo‐[6]helicene precursors. Their chiroptical properties have been investigated in correlation with density functional theory (DFT) calculations, which allowed to confidently assign the absolute configuration of the helicene arms and to characterize the different electronic transitions, including the low energy charge transfer excitation from helicenes to BTD. The enantiomerically pure fluorophores (M,M)‐ and (P,P)‐BTD‐bis([6]helicene), which exist in solution as two main conformers, according to the DFT calculations, show CPL activity in solution, with glum factors of ≈1.7×10−3 at λem=525 nm, and also in the solid state, with glum factors of ≈1.2×10−3 in spite of the strong decrease of the quantum efficiency. [ABSTRACT FROM AUTHOR]

Implementing sustainable crop protection practices is crucial to protect global harvests and ensure high-quality food supplies. While priming is an established method in seed production for the fortification of plants against various stresses, it is not yet a standard practice in transplant cultivation. Thus, we evaluated the long-term effects of thermopriming—a heat-based priming technique—on the growth, development, and fruit yield of tomato plants. Following a recovery period of about six weeks for thermoprimed plants without stress inducers, we subjected them to subsequent salt stress to ascertain the persistence of the priming effects. Additionally, we compared the efficacy of thermopriming with benzothiadiazole (BTH), a chemical elicitor, in enhancing plant resilience to abiotic stress. While BTH application negatively impacted both plant growth and fruit health, thermopriming showed no such adverse effects on these parameters. Instead, thermopriming initially enhanced the plant defense mechanisms by increasing the accumulation of protective phenols and flavonoids in the leaves. Interestingly, while thermopriming did not alter the response to salt stress, it notably strengthened the overall resilience of the plants. Our findings underscore both the potential and temporal constraints of thermopriming memory. Nonetheless, primed plants exhibited temporarily increased stress tolerance, offering a means to safeguard the offspring. [ABSTRACT FROM AUTHOR]

Four donor‐acceptor (D‐A) polymers are synthesized by combining two different electron donors (truxene and its more electron rich triaza analogue, triindole) with an electron‐deficient monomer (benzothiadiazole) through two different positions (2,7,13 or 3,8,13) and their optoelectronic properties are studied by theoretical and experimental methods. One of the polymers exhibits remarkable sensing capabilities for explosive nitraoaromatics while another demonstrated efficient photocatalytic activity in the aerobic sulfoxidation of the sulfur mustard simulant 2‐chloro‐ethyl ethyl sulfide (MGS) sulfoxidation. These results highlight their potential applications in defense‐related areas. Moreover, the structure‐performance relationships observed among the four polymers have enabled us to deepen the understanding of the mechanisms underlying the performance of these polymers in the aforementioned applications, thereby providing valuable insights to further improve their properties. [ABSTRACT FROM AUTHOR]

The development of highly efficient deep red materials with emission wavelength beyond 650 nm remains a big challenge due to the constraints imposed by the energy gap rule. In this work, a donor‐acceptor‐donor type emitter, 4,7‐bis (10‐(4‐(tert‐butyl) phenyl)‐10H‐phenothiazin‐3‐yl) benzo[c][1,2,5] thiadiazole (TBPPTZ) is designed and synthesized. Resulting from the slight twist angle between the donor and acceptor units, TBPPTZ exhibits nearly planar conformation and an extended conjugated structure. TBPPTZ shows a deep red emission peak at 687 nm and aggregation induced emission property with a high photoluminescence quantum yield of 45 % in neat thin film. The optimized organic light‐emitting diode (OLEDs) utilizing TBPPTZ as the non‐doped emissive layer obtains a high external quantum efficiency (EQE) up to 2.51 % with an electroluminescence (EL) peak at 676 nm, aligning with the Commission Internationale de L'Eclairage (CIE) coordinates (0.68, 0.31), which shows a small EQE roll‐off of only 5.6 % at 100 cd m−2. Additionally, the doped OLED achieves an EQE up to 5.09 %, with an EL peak at 656 nm and CIE coordinates of (0.65, 0.34). The findings of this research not only contribute to achieve highly efficient deep red OLEDs but also offer a novel and effective deep red molecular strategy to realize high‐quality OLEDs. [ABSTRACT FROM AUTHOR]

Diblock conjugated oligomers are π-conjugated molecules that contain two segments having distinct frontier orbital energies and HOMO-LUMO gap offsets. These oligomers are of fundamental interest to understand how the distinct π-conjugated segments interact and modify their excited state properties. The current paper reports a study of two series of diblock oligomers that contain oligothiophene (Tn) and 4,7-bis(2-thienyl)-2,1,3-benzothiadiazole (TBT) segments that are coupled by either ethynyl (-C≡C-) or trans-(-C≡C-)2Pt(II)(PBu3)2 acetylide linkers. In these structures, the Tn segment is electron rich (donor), and the TBT is electron poor (acceptor). The diblock oligomers are characterized by steady-state and time-resolved spectroscopy, including UV-visible absorption, fluorescence, fluorescence lifetimes, and ultrafast transient absorption spectroscopy. Studies are compared in several solvents of different polarity and with different excitation wavelengths. The results reveal that the (-C≡C-) linked oligomers feature a delocalized excited state that takes on a charge transfer (CT) character in more polar media. In the (-C≡C-)2Pt(II)(PBu3)2-linked oligomers, there is weak coupling between the Tn and TBT segments. Consequently, short wavelength excitation selectively excites the Tn segment, which then undergoes ultrafast energy transfer (~1 ps) to afford a TBT-localized excited state. [ABSTRACT FROM AUTHOR]

Chardonnay is a non-floral grape with economic value and nutritional properties that is widely grown in northwestern China. However, limited research has been conducted on exogenous spraying to regulate volatile compound metabolism (especially isoprene metabolism) in Chardonnay grapes. Benzothiadiazole (BTH) can induce disease resistance and augment the contents of phenolics and volatile compounds in grapes. This study aimed to evaluate the influence of BTH on the accumulation of isoprene aroma, carotenoid levels and the activity profiles of key enzymes. Chardonnay grapevines were treated with 0.37 mM BTH at veraison to investigate the impact on physicochemical parameters, carotenoids, metabolic enzyme activities, and free and bound isoprenoids in developing Chardonnay grapes. The results showed that reducing sugars, and total soluble solids of BTH-treated grapes increased, while the content of titratable acidity, β-carotene, zeaxanthin, β-cryptoxanthin, chlorophyll, and total carotenoids in treated ripe grapes decreased relative to control berries. BTH-treated ripe grapes exhibited elevated levels of bound norisoprenoids and three key enzemy activities (carotenoid cleavage dioxygenase, phytoene synthase, lycopene β-cyclase), with a slight decrease in free norisoprenoids. Free and bound terpenoids profiles were also significantly enhanced by BTH treatment at veraison. Our findings offer novel perspectives into the modulation of isoprene biosynthesis in grape berries when exposed to BTH. [ABSTRACT FROM AUTHOR]

An efficient access to the novel 5-(aryl)amino-1,2,3-triazole-containing 2,1,3-benzothiadiazole derivatives has been developed. The method is based on 1,3-dipolar azide–nitrile cycloaddition followed by Buchwald–Hartwig cross-coupling to afford the corresponding N-aryl and N,N-diaryl substituted 5-amino-1,2,3-triazolyl 2,1,3-benzothiadiazoles under NHC-Pd catalysis. The one-pot diarylative Pd-catalyzed heterocyclization opens the straightforward route to triazole-linked carbazole-benzothiadiazole D-A systems. The optical and electrochemical properties of the compound obtained were investigated to estimate their potential application as emissive layers in OLED devises. The quantum yield of photoluminescence (PLQY) of the synthesized D-A derivatives depends to a large extent on electron-donating strengths of donor (D) component, reaching in some cases the values closed to 100%. Based on the most photoactive derivative and wide bandgap host material mCP, a light-emitting layer of OLED was made. The device showed a maximum brightness of 8000 cd/m2 at an applied voltage of 18 V. The maximum current efficiency of the device reaches a value of 3.29 cd/A. [ABSTRACT FROM AUTHOR]

A novel benzothiadiazole-based donor-acceptor type polymer, resistive random access memory (RRAM) material, poly{[4,4'-(2,7-diphenyl-9H-fluorene-9,9-diyl)bis(N,N-diphenylaniline)]-alt-[4,7-bis(4-dodecyl-5-vinylthiophen-2- yl)benzo[c][1,2,5] thiadiazole]} (PFVT) was synthesized. By using PFVT as the active layer, the as-fabricated electronic device with a configuration of Al/PFVT/ITO (ITO: indium tin oxides) exhibites a nonvolatile RRAM performance. During 50 consecutive cycle-to-cycle measurements, the observed average switch-on voltage, switch-off voltage and ON/OFF current ratio are (−0.54 ± 0.01) V, (2.42 ± 0.05) V, and 1.5×10³, respectively. The cycle-to-cycle variation for the programming voltage is less than 2.1%, suggesting excellent reliability. After thermal annealing at 200 ℃, the switch-on and switch-off voltages decrease to (−0.49±0.01) V and (2.27±0.02) V, respectively, due to the enhanced material crystallinity. The switching mechanism can be assigned to the intramolecular charge-transfer occurred in the materials system. The ON and OFF-state currents can be fitted by the Ohmic current model and space-charge-limited current model, respectively. The switchon voltage is highly associated with the bandgap of the materials. For comparison purpose, 4,4′-(2,7-diphenyl-9H-fluorene-9,9- diyl)bis(N,N-diphenylaniline) was replaced with phenyl group to synthesize poly[4-(4-dodecyl-5-((E)-4- methylstyryl)thiophen-2-yl)-7-(4-dodecyl-5-((E)-prop-1-en-1-yl)thiophen-2-yl)benzo[c][1,2,5]thiadiazole](PPVT). In contrast to PFVT, PPVT also shows the similar RRAM performance, with a bigger switch-on voltage and a smaller ON/OFF current ratio. Replacement of bulky fluorene unit with phenyl unit leads to a sharp decrease in the thermal stability of the material and an increase in the bandgap. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The rapid synthesis of structurally complicated electron donors & acceptors still remains a major challenge in organic solar cells (OSC). In this work, we developed a highly efficient strategy to access long‐chain oligomeric donor and acceptors for OSC applications. A series of cyclopentadithiophene (CPDT) and benzothiadiazole (BT)‐based π‐conjugated oligomers, i.e., three oligomeric acceptors (BTDT)n‐IC (n = 1—3) and one long‐chain oligomeric donor (BTDT)4‐RD, are facilely synthesized by an atom‐ and step‐economical, and labor‐saving direct C—H arylation (DACH) reaction (i.e., C—H/C—Br cross coupling). Note that (BTDT)4‐RD involving five CPDT, four BT and two rhodamine (RD) building blocks is the longest oligomeric donor in the fullerene‐free OSC devices ever reported. The dependence of the structure‐property‐performance correlation of (BTDT)n‐IC (n = 1—3) and (BTDT)4‐RD on the π‐conjugation lengths is thoroughly investigated by opto‐electrochemical measurements, bulk heterojunction (BHJ) OSC devices and microscopies. The (BTDT)1‐IC:PBDB‐T and (BTDT)4‐RD:Y6 BHJs achieve power conversion efficiencies of 9.14% and 4.51%, respectively. Our findings demonstrate that DACH reaction is a powerful tool to tune the opto‐electronic properties and device performances by regulating the lengths of π‐conjugated oligomers with varied numbers of repeating units. [ABSTRACT FROM AUTHOR]

In pot culture in glass house, we studied the chickpea disease management using synthetic elicitors and defence enzymes against Fusarium oxysporum f. sp. ciceris [MF803741] on chickpea cv. JAKI 9218. Six synthetic chemical elicitors (benzothiadiazole, salicylic acid, potassium silicate, potassium phosphate, humic acid and carbendazim) were used at 3-concentrations. (1.0, 2.0 and 3.0 mM) on test chemo-fortify chickpea cv. JAKI 9218. The changes in dynamics of enzyme activity were recorded from upto 24 days from sowing. Among these, salicylic acid fortified at a concentration of 3.0 mM enriched seeds had the lowest incidence of wilt at 17.3 %, 66.0 % reduction in disease and five defence proteins, namely 14, 29, 53, 67, and 83.4 kDa, and four enzyme isoforms. That is, PO1 to PO4 (peroxidase) were expressed; PPO1 to PPO4 (polyphenol oxidases) and three SOD1 to SOD3 (superoxide dismutase). Besides dynamic changes in enzyme activity, peroxidase (absorbance 1.50), polyphenol oxidase (absorbance 1.42), superoxide dismutase (7.60 units), and phenol content (19.24) μg catechol/min/gram tissue increased by 18 days. Hence, using the least quantity of elicitors enhanced and triggered the defence profiles in form of antioxidants, enzymes and proteins in chickpea against to wilt pathogen. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The rapid synthesis of structurally complicated electron donors & acceptors still remains a major challenge in organic solar cells (OSC). In this work, we developed a highly efficient strategy to access long‐chain oligomeric donor and acceptors for OSC applications. A series of cyclopentadithiophene (CPDT) and benzothiadiazole (BT)‐based π‐conjugated oligomers, i.e., three oligomeric acceptors (BTDT)n‐IC (n = 1—3) and one long‐chain oligomeric donor (BTDT)4‐RD, are facilely synthesized by an atom‐ and step‐economical, and labor‐saving direct C—H arylation (DACH) reaction (i.e., C—H/C—Br cross coupling). Note that (BTDT)4‐RD involving five CPDT, four BT and two rhodamine (RD) building blocks is the longest oligomeric donor in the fullerene‐free OSC devices ever reported. The dependence of the structure‐property‐performance correlation of (BTDT)n‐IC (n = 1—3) and (BTDT)4‐RD on the π‐conjugation lengths is thoroughly investigated by opto‐electrochemical measurements, bulk heterojunction (BHJ) OSC devices and microscopies. The (BTDT)1‐IC:PBDB‐T and (BTDT)4‐RD:Y6 BHJs achieve power conversion efficiencies of 9.14% and 4.51%, respectively. Our findings demonstrate that DACH reaction is a powerful tool to tune the opto‐electronic properties and device performances by regulating the lengths of π‐conjugated oligomers with varied numbers of repeating units. [ABSTRACT FROM AUTHOR]

The authors discuss results from studying the photophysical properties of linear molecules based on 2,1,3-benzothiadiazole, specifically 4,7-di([para-biphenyl]-4-yl)benzothiadiazole (Ph-Ph-BTD) and 4,7-bis(2,5-dimethyl-[1,1'-biphenyl]-4-yl)benzothiadiazole (Ph-Xy-BTD). The synthesis of a new phenylxylene derivative of benzothiadiazole—Ph-Xy-BTD—is described. The thermal stability of the Ph-Ph-BTD and Ph-Xy-BTD compounds is studied. Their parameters of melting and solubility are determined, and the absorption spectra of solutions in n-hexane and THF are recorded. It is shown that having pendant methyl substituents in Ph-Xy-BTD lowers its melting point, increases its solubility, reduces the probability of a transition between the ground and excited state orbitals, and raises the energy of transition. The effect solvation has on the spectra, fluorescence quantum yield, and lifetime of the fluorescence of compounds in THF and n-hexane is studied. Static dipole moments in the ground (HOMO) and excited states (LUMO) of Ph-Ph-BTD and Ph-Xy-BTD molecules are determined. It is shown that the conformation of the excited state (LUMO) changes during the relaxation of the solvate and becomes more planar than that of the ground state (HOMO). A relationship is revealed between the conformation of the excited state of the studied compounds and the polarity of the solvent. [ABSTRACT FROM AUTHOR]

The embedding of metal nanoparticles (NPs) in metal–organic frameworks (MOFs) has attracted a wide range of attention in the field of catalysis due to the high agglomeration resistance of NPs in MOFs. In this work, a Cu-(II)-based MOF with the formula {[Cu1.5(TPA)-(BIBT)]·4DMF·6H2O]}n (1) (H3TPA = tris-(4′-carboxybiphenyl)-amine; BIBT = 4,7-di-(1H-imidazol-1-yl)-benzo-[c]-[1,2,5]-thiadiazole; and DMF = N,N-dimethylformamide) was synthesized under solvothermal condition. Structural analysis revealed that Cu-MOF 1 possessed 3-fold interpenetrated three-dimensional (3D) coordination frameworks with large one-dimensional (1D) channels along the a-axis. Due to the interaction between Ag and S/N, Ag NPs could be encapsulated into the pores of Cu-MOF 1 to generate Ag NPs and MOF composites, xAg/1 (x = 0.3, 0.5, 0.8, and x was the molar ratios of AgNO3 with Cu-MOF 1 in the synthesis), which was further demonstrated by powder X-ray diffraction, Fourier transform infrared, scanning electron microscopy, transmission electron microscope, energy dispersive spectrometer, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller (BET) analysis. In addition, synthesized 0.5Ag/1 exhibited outstanding catalytic activity for the A3-coupling reaction of aldehyde, alkyne, and amine with high recyclability. This work presents a viable strategy for using Cu-(II)-based MOF loading with Ag NPs as heterogeneous catalysts for the A3-coupling reaction. [ABSTRACT FROM AUTHOR]

The conjugated small molecules (CSMs) are an interesting class of semiconductor materials for thin‐film electronics. Herein, the synthesis of two novel donor–acceptor small molecules BBT‐H and BBT‐F is reported and the impact of morphology rearrangement upon thermal annealing on hole‐transport characteristics of thin films based on them is investigated. It is shown that morphological changes occurring upon annealing of thin films based on fluorine‐containing molecule BBT‐F result in spectacular enhancement of hole mobilities by seven times from 2.13 × 10−4 to 1.52 × 10−3 cm2V−1 s−1, whereas hole mobilities of nonfluorinated BBT‐H do not show any considerable changing. This effect features the importance of molecular engineering for the design of promising CSMs for next‐generation thin‐film electronics. [ABSTRACT FROM AUTHOR]

In order to achieve a multifunctional compound with potential application in organic photonics and electronics, a multidonor benzothiadiazole derivative was rationally designed and synthesized employing microwave irradiation as energy source, increasing the process efficiency about yields and reaction times in comparison with conventional conditions. This powerful compound displayed solvatochromism and showed efficient behavior as red optical waveguide with low OLC around 10−2 dB μm−1 and with the capacity of light transmission in two directions. In addition, the proposed derivative acted as efficient p‐type semiconductor in organic field‐effect transistors (OFETs) with hole mobilities up 10−1 cm2 V−1 s−1. This corroborates its multifunctional character, thus making it a potential candidate to be applied in hybrid organic field‐effect optical waveguides (OFEWs). [ABSTRACT FROM AUTHOR]

Two new luminescent ligands, 4‐(2‐pyridine)‐7‐methyl‐2,1,3‐benzothiadiazole (L1) and 4‐(2,2‐bipyridine)‐7‐methyl‐2,1,3‐benzothiadiazole (L2), based on 2,1,3‐benzothiadiazole and pyridine or bipyridine were obtained by Suzuki coupling reactions. DFT and TD‐DFT type calculations have been performed on L1 and L2 in order to assign their experimental UV‐visible and emission bands. Reaction of L1 and L2 with metal(II) chlorides (M=Zn, Mn, Cu) provided the neutral complexes of formulas [ZnL1Cl2] (1), [Zn(L1)2Cl2] (2), [ZnL2Cl2] (3), [MnL2Cl2] ⋅ 0,5CH2Cl2 (4) and [CuL2Cl2] ⋅ H2O (5) which have been structurally characterized. The Zn(II) ions in 1 and 2 are four‐coordinate in somewhat distorted tetrahedral N2Cl2 surroundings with L1 adopting bidentate (1) and monodentate (2) coordination modes. Complexes 3–5 are isostructural and their metal atoms are five‐coordinate in distorted square pyramidal environments with three nitrogen atoms from the tridentate L2 ligand and a chlorine building the basal plane and another chlorine atom occupying the apical position. The three Zn(II) complexes are strongly luminescent in solution and the solid state, while the cryomagnetic study of the paramagnetic compounds 4 and 5 in the temperature range 2.9–300 K shows a Curie‐Weiss behaviour typical of small antiferromagnetic interactions which are mediated by weak intermolecular contacts. [ABSTRACT FROM AUTHOR]

Among short donor–acceptor molecules with a central benzothiadiazole fragment, 4,7-di-2-thienyl-2,1,3-benzothiadiazole (T-BTD) is one of the most well-known compounds, valued for its photophysical and semiconductor properties. We have synthesized a derivative of 4,7-di-2-thienyl-2,1,3-benzothiadiazole with trimethylsilyl end-substituents, 4,7-bis(5-(trimethylsilyl)thiophen-2-yl)benzothiadiazole (TMS-T-BTD). The phase transition parameters and thermal stability of T-BTD and TMS-T-BTD were investigated using DSC and TGA methods. The presence of the trimethylsilyl end-groups in TMS-T-BTD significantly enhances solubility, increases the melting temperature, and improves the resistance of TMS-T-BTD to evaporation in the liquid state. Single crystals of T-BTD and TMS-T-BTD were grown from solutions, with the largest sizes being 7 × 2 × 0.5 mm3 and 8 × 1 × 0.45 mm3, respectively. Using single-crystal X-ray diffraction at 293 K, the crystal structure of T-BTD was refined in the rhombic system (sp.gr. Pcab, Z = 8), while for TMS-T-BTD, it was determined for the first time in the monoclinic system (sp.gr. P21/c, Z = 4). The relationship between observed growth anisotropy and molecular packing in the crystals was analyzed. The results of investigations into the spectral-fluorescent properties of solutions in hexane and THF are presented. The solvatochromic effect was studied in a series of solvents, including hexane, THF, dichloromethane, and acetonitrile. The photostability of the compounds in hexane solutions was examined. It was found that the quantum yield of photodestruction for T-BTD is 13 times higher than that of TMS-T-BTD. The fluorescent properties of T-BTD and TMS-T-BTD crystals were investigated. [ABSTRACT FROM AUTHOR]

Despite the wealth of studies on benzothiadiazole (BTH) and its capacity to modulate grape polyphenol metabolism, comprehensive data detailing polyphenol accumulation at various grape growth stages remain scarce. Therefore, the present study utilized pre-harvest (at 21 days after flowering) canopy-applied BTH (50 mg/L) on Cabernet Gernischt and Cabernet Franc grapes to investigate the physicochemical and polyphenolic changes during grape maturation. The results showed that BTH treatment significantly affected the accumulation of total phenols, flavonoids, flavanols, anthocyanins, and tannins. Concurrently, it induced an increase in colorimetric parameters (CIRG, L*, b*, a*, and C*ab), resulting in the treated grapes exhibiting a greater color intensity and enhanced red-bluish colorimetric characteristics. Moreover, the BTH treatment amplified the anthocyanin content in the grapes, with the levels of petunidin-3-O-glucoside and peonidin-3-O-glucoside exhibiting remarkable increases, particularly in the Cabernet Franc grape. Notably, the content of peonidin-3-O-glucoside even surpassed that of malvidin-3-O-glucoside throughout the growth stages, indicating significant advantages in the treated samples. Additionally, the levels of flavanol, flavonols, phenolic acids, and stilbenes experienced a significant boost post-treatment. In conclusion, the application of BTH treatment can effectively enhance the accumulation of polyphenols and intensify the color of Cabernet Gernischt and Cabernet Franc grapes, thereby significantly improving the overall quality of wine grapes and ensuring the production of higher-quality wines. The research findings will serve as a theoretical foundation and provide scientific data for the appropriate utilization of BTH in wine grape cultivation.

Diblock conjugated oligomers are π-conjugated molecules that contain two segments having distinct frontier orbital energies and HOMO-LUMO gap offsets. These oligomers are of fundamental interest to understand how the distinct π-conjugated segments interact and modify their excited state properties. The current paper reports a study of two series of diblock oligomers that contain oligothiophene (Tn) and 4,7-bis(2-thienyl)-2,1,3-benzothiadiazole (TBT) segments that are coupled by either ethynyl (-C≡C-) or trans-(-C≡C-)2Pt(II)(PBu3)2 acetylide linkers. In these structures, the Tn segment is electron rich (donor), and the TBT is electron poor (acceptor). The diblock oligomers are characterized by steady-state and time-resolved spectroscopy, including UV-visible absorption, fluorescence, fluorescence lifetimes, and ultrafast transient absorption spectroscopy. Studies are compared in several solvents of different polarity and with different excitation wavelengths. The results reveal that the (-C≡C-) linked oligomers feature a delocalized excited state that takes on a charge transfer (CT) character in more polar media. In the (-C≡C-)2Pt(II)(PBu3)2-linked oligomers, there is weak coupling between the Tn and TBT segments. Consequently, short wavelength excitation selectively excites the Tn segment, which then undergoes ultrafast energy transfer (~1 ps) to afford a TBT-localized excited state.

In this work, two novel hyperbranched conjugated polymers poly(tris(4-(10-(2-ethylhexyl)-10H-phenoxazin-3-yl)phenyl)amine) (P1) and poly (tris(4-(7-(benzo[c][1,2,5]thiadiazol-4-yl)-10-(2-ethylhexyl)-10H-phenoxazin-3-yl)phenyl)amine) (P2) have been successfully synthesized via Direct polycondensation in the presence of Pd(OAc)2 as a catalyst. The chemical structures of novel conjugated polymers then were determined via Fourier-transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H NMR). Subsequently, the optical properties of conjugated polymers in different solvents were investigated via UV–Vis absorption and fluorescence emission (PL) spectroscopies, and were analyzed for optoelectronic applications.

[Display omitted] • A benzothiadiazole COF, TpBTD-COF, is developed as a photocatalyst. • TEMPO, a mediator, smooths the electron transfer over TpBTD-COF. • Cooperative photocatalysis is assembled with TEMPO over TpBTD-COF. • Outstanding results in selective aerobic sulfoxidation are achieved. • TpBTD-COF sustains multiple cycles of sulfoxidation. Covalent organic frameworks (COFs) are promising visible light photocatalysts for aerobic oxidation reactions. However, COFs usually suffer from the assault of reactive oxygen species, leading to hindered electron transfer. This scenario could be addressed by integrating a mediator to promote photocatalysis. Starting with 4,4′-(benzo-2,1,3-thiadiazole-4,7-diyl)dianiline (BTD) and 2,4,6-triformylphloroglucinol (Tp), TpBTD-COF is developed as a photocatalyst for aerobic sulfoxidation. Adding an electron transfer mediator 2,2,6,6-tetramethylpiperidine-1‑oxyl (TEMPO), the conversions are radically accelerated, over 2.5 times of that without TEMPO. Moreover, the robustness of TpBTD-COF is preserved by TEMPO. Remarkably, TpBTD-COF could endure multiple cycles of sulfoxidation, even with higher conversions than the fresh one. TpBTD-COF photocatalysis with TEMPO implements diverse aerobic sulfoxidation by an electron transfer pathway. This work highlights that benzothiadiazole COFs are an avenue for tailor-made photocatalytic transformations. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Only a few fused benzothiadizole (BTz) based conjugated polymers have been applied in organic field‐effect transistors (OFETs), and their performances were low, mainly due to the lack of available building blocks and in‐depth study of the relationship between structure and performance. Herein, we report two isomeric fused BTz‐based building blocks (M1 and M2) and their copolymers PBTzVBTz‐T and PBTzVBTz‐TT, PTVT‐T and PTVT‐TT. DFT study showed all polymers had nearly planar backbone geometries, and PBTzVBTz‐TT exhibited the most linear backbone. PTVT‐T and PTVT‐TT exhibited red‐shift absorption spectra and deeper LUMO level than those of PBTzVBTz‐T and PBTzVBTz‐TT. Thin film microstructure study demonstrated PBTzVBTz‐TT and PTVT‐TT had edge‐on molecular orientation, while the others had the mixed molecular orientation of edge‐on and face‐on. Furthermore, PBTzVBTz‐TT had the longest coherence length in thin film. All these features of PBTzVBTz‐TT resulted in its highest carrier mobility of 0.1 cm2·V–1·s–1 among these polymers. [ABSTRACT FROM AUTHOR]

Pre-harvest application of elicitors improves grape quality, specifically the phenolic compounds and color characteristics. Limited research has been conducted on the impact of elicitors on the C6 compounds found in grapes. This is due to lack of comprehensive studies examining the combined effects of bound aroma compounds, enzyme activity, and substrate availability. This study aimed to assess the impact of benzothiadiazole (BTH) on the physicochemical properties and C6 compounds of Cabernet Gernischt grapes during ripening. Compared with the control group (CK), BTH treatment significantly increased the 100-berry weight, skin/berry ratio, pH, total phenolic content, and total flavonoid content in ripe grapes. Additionally, BTH treatment led to significant reductions in reducing sugar, total soluble solids, titratable acidity, linoleic acid, linolenic acid, and free C6 aldehydes. Furthermore, BTH treatment significantly decreased the contents of free C6 alcohols and increased the levels of free and bound C6 esters. BTH treatment also increased the activities of lipoxygenase, alcohol dehydrogenase, and alcohol acetyltransferase enzymes, while it decreased the activity of hydroperoxide lyase enzyme. The application of BTH resulted in changes to the physicochemical properties and levels of C6 compounds in Cabernet Gernischt grapes by up-regulating enzyme activity and down-regulating precursors. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Only a few fused benzothiadizole (BTz) based conjugated polymers have been applied in organic field‐effect transistors (OFETs), and their performances were low, mainly due to the lack of available building blocks and in‐depth study of the relationship between structure and performance. Herein, we report two isomeric fused BTz‐based building blocks (M1 and M2) and their copolymers PBTzVBTz‐T and PBTzVBTz‐TT, PTVT‐T and PTVT‐TT. DFT study showed all polymers had nearly planar backbone geometries, and PBTzVBTz‐TT exhibited the most linear backbone. PTVT‐T and PTVT‐TT exhibited red‐shift absorption spectra and deeper LUMO level than those of PBTzVBTz‐T and PBTzVBTz‐TT. Thin film microstructure study demonstrated PBTzVBTz‐TT and PTVT‐TT had edge‐on molecular orientation, while the others had the mixed molecular orientation of edge‐on and face‐on. Furthermore, PBTzVBTz‐TT had the longest coherence length in thin film. All these features of PBTzVBTz‐TT resulted in its highest carrier mobility of 0.1 cm2·V–1·s–1 among these polymers. [ABSTRACT FROM AUTHOR]

Some original poly(tetrasubstituted imidazole)s incorporating different units were synthesized and characterized. These materials were obtained via a cascade polycondensation process assisted by microwave irradiation that was developed by our team. This time, we integrated two well-known chromophore structures into the macromolecular backbone, which were benzothiadiazole (BTD) and diketopyrrolopyrrole (DKPP). These new polymers were fully characterized: their chemical structures were confirmed using NMR spectroscopy and their thermal, optical and electrochemical properties were investigated and compared with a reference polymer containing a phenyl spacer instead of the mentioned chromophore units. These materials were found to exhibit a large Stokes shift of up to 350 nm. Furthermore, a polymer presenting large absorption on the UV–visible range and an emission close to the near-infrared region was obtained by coupling the mentioned moieties. According to the established properties of this latter polymer, it presents a potential for applications in biological imaging or optoelectronic devices. [ABSTRACT FROM AUTHOR]

Ladder polymers with poly(diketopyrrolopyrrole) (DPP) moieties have recently attracted enormous interest for a large variety of opto-electronic applications. Since the rigidity of the backbone increases with ladderization, a strong influence on the self-organization of thin films is expected. We study the molecular orientation of DPP-based ladder polymers in about 50 nm thin films using polarization modulation-infrared reflection-absorption spectroscopy (PM-IRRAS). Exemplarily, for one polymer, the orientation in thicker films is qualitatively investigated by infrared spectroscopy in transmission. Further, this method allows us to rule out the effects of a possible azimuthal ordering, which would affect the analysis of the orientation by PM-IRRAS. For all polymers, the long axis of the polymer backbone is preferentially oriented parallel to the substrate surface, pointing to a high degree of ordering. It is suggested that the choice of the side chains might be a promising way to tune for face-on and edge-on orientations. The exemplarily performed investigation of interface properties on substrates with different work functions suggests that the choice of the side chains has a minor effect on the interfacial electronic interface structure. [ABSTRACT FROM AUTHOR]

[Display omitted] Three new 2,1,3-benzothiadiazole-containing luminophores with different electron deficiency of acceptor block have been prepared via the Pd-catalyzed Suzuki cross-coupling and nucleophilic fluorine substitution with cyano group. Photophysical and electroluminescent properties of the compounds obtained were investigated to estimate their potential for optoelectronic applications. The introduction of two fluorine atoms in the benzothiadiazole moiety leads to the hypsochromic shift of the electroluminescent emission, whereas the incorporation of two cyano groups shifts it into the long-wave region. All synthesized compounds were used as emissive layers in OLED devises. [ABSTRACT FROM AUTHOR]

An efficient access to the novel 5-(aryl)amino-1,2,3-triazole-containing 2,1,3-benzothiadiazole derivatives has been developed. The method is based on 1,3-dipolar azide–nitrile cycloaddition followed by Buchwald–Hartwig cross-coupling to afford the corresponding N-aryl and N,N-diaryl substituted 5-amino-1,2,3-triazolyl 2,1,3-benzothiadiazoles under NHC-Pd catalysis. The one-pot diarylative Pd-catalyzed heterocyclization opens the straightforward route to triazole-linked carbazole-benzothiadiazole D-A systems. The optical and electrochemical properties of the compound obtained were investigated to estimate their potential application as emissive layers in OLED devises. The quantum yield of photoluminescence (PLQY) of the synthesized D-A derivatives depends to a large extent on electron-donating strengths of donor (D) component, reaching in some cases the values closed to 100%. Based on the most photoactive derivative and wide bandgap host material mCP, a light-emitting layer of OLED was made. The device showed a maximum brightness of 8000 cd/m2 at an applied voltage of 18 V. The maximum current efficiency of the device reaches a value of 3.29 cd/A.

Visible‐light‐driven semiconductor photoelectrodes are promising new devices for on‐demand photocathodic generation of hydrogen peroxide. Herein, the fabrication of organic polymeric photocathodes employing poly(4,7‐di(thiophen‐2‐yl)benzo[c][1,2,5]thiadiazole) (pThBTD), and comparatively seven other related derivatives is reported. The monomer dithienobenzodithiazole can be directly polymerized on an electrode via two methods: electropolymerization or iodine‐vapor‐assisted polymerization. Both give polymers with wide visible light absorption and suitable stability for photoelectrodes. These methods yield different active layer morphologies, with electropolymerization yielding photocathodes with better performance. Critical issues affecting oxygen reduction photocurrents are evaluated, namely thickness, wettability, and pH. Photocathodic oxygen reduction currents, as well as photovoltages, are among the highest reported for an organic photoelectrocatalyst, and pThBTD films can stably produce H2O2 with high faradaic yield over at least 8 h. This study shows that single‐component organic semiconductor devices can be highly competitive versus more complex heterostructures and that such low‐bandgap organic polymers can afford remarkable stability. [ABSTRACT FROM AUTHOR]

Organic electrode materials based on conjugated dicarboxylate moieties are particularly attractive to develop metal‐ion organic batteries. Exhibiting good stability properties in liquid electrolytes, such organic electrode materials can reversibly store alkali metal ions (Li, Na or K) at low working potential. Although many molecular designs have been investigated in the last decade, conjugated dicarboxylates are impeded by low coulombic efficiencies, especially at the first cycle, and sluggish kinetics in most cases. Herein, a new strategy in the design of conjugated carboxylates by fusing a thiadiazole heterocycle to the terephthalate core is reported. The synthesis and electrochemical performance of dilithium‐2,1,3‐benzothiadiazole‐4,7‐dicarboxylate (Li2‐DCBTZ) as positive electrode material is investigated for the first time. Next to being a new structural design, the presence of the thiadiazole ring enables (i) a better conjugation of π‐n electrons leading to a benefit in terms of rate capability, and (ii) a better stabilizing coordination network for Li ions through both oxygen and nitrogen atoms. In addition, the reduced state in Li4‐DCBTZ is stabilized due to a maintained aromaticity in the heteroaromatic core in comparison to the parent terephthalate. Theoretical calculations on the Li‐ion storage mechanism and bonding character support the experimental work. [ABSTRACT FROM AUTHOR]

Substituted 2,1,3-benzothiadiazole (BTD) is a widely used electron acceptor unit for functional organic semiconductors. Difluorination or annulation on the 5,6-position of the benzene ring is among the most adapted chemical modifications to tune the electronic properties, though each sees its own limitations in regulating the frontier orbital levels. Herein, a hitherto unreported 5,6-annulated BTD acceptor, denoted as ssBTD, is designed and synthesized by incorporating an electron-withdrawing 2-(1,3-dithiol-2-ylidene)malononitrile moiety via aromatic nucleophilic substitution of the 5,6-difluoroBTD (ffBTD) precursor. Unlike the other reported BTD annulation strategies, this modification leads to the simultaneous decrease in both frontier orbital energies, a welcoming feature for photovoltaic applications. Incorporation of ssBTD into conjugated polymers results in materials boasting broad light absorption, dramatic solvatochromic and thermochromic responses (>100 nm shift and a band gap difference of ∼0.28 eV), and improved crystallinity in the solid state. Such physical properties are in accordance with the combined electron-withdrawing effect and significantly increased polarity associated with the ssBTD unit, as revealed by detailed theoretical studies. Furthermore, the thiolated ssBTD imbues the polymer with ambipolar charge transport property, in contrast to the ffBTD-based polymer, which transports holes only. While the low mobilities (10-4 to 10-5 cm2 V-1 s-1) could be further optimized, detailed studies validate that the thioannulated BTD is a versatile electron-accepting unit for the design of functional stimuli-responsive optoelectronic materials.

Meloidogyne spp. is an important pest of cucurbits in tunnel farming of vegetables in Pakistan. A cucumber germplasm was evaluated for resistance against the root-knot nematode (RKN, Meloidogyne incognita) based on the number of galls and egg masses recorded under glass house conditions. All the cucumber accessions showed varying responses towards the RKN inoculation. Out of the fifteen cucumber lines, two were found to be moderately susceptible to M. incognita, ten were susceptible while the other three were highly susceptible. For the management of the nematodes, resistance was induced in a highly susceptible cucumber accession (28294) by the application (both drench and foliar) of elicitors, i.e., salicylic acid (SA) and benzothiadiazole (BTH). The application of SA and BTH significantly enhanced the defence mechanism of the cucumber plants when compared to the control. Increased enzymatic activities in the cucumber plants as the result of the elicitor applications were determined through spectrophotometer to correlate the induced resistance. There was a significant increase in the enzymatic activities when compared to the control in the cucumber plants, which ultimately enhanced the resistance as there was a decrease in the number of galls and egg masses per plant. The enzymatic antioxidant activity was also found to increase in response to the nematode infection. Both SA and BTH were reported to play pivotal roles in inducing resistance in cucumber plants against M. incognita.

Side chains play an important role in the photo-oxidation process of low band gap (LBG) polymers. For example, it has been shown that their photostability can be increased by the introduction of aromatic-oxy-alkyl links. We studied the photostability of prototypical LBG polymers with alkyl and oxyalkyl side chains during irradiation with white light (AM 1.5 conditions) in dry air using UV/vis and IR spectroscopy. Though its degradation kinetics were distinctly affected by the presence or absence of oxygen in the structure of the side chains, in particular cases, the stability was more affected by the presence of linear or branched side chains. Moreover, we showed that the exact position of the alkyl/oxyalkyl side chain at the polymer backbone could be crucial. Although minor effects of chemical modifications on the electronic parameters (ionization potential and gap) were observed, the molecular orientation, determined by polarization modulation-infrared reflection-absorption spectroscopy (PMIRRAS), could be affected. The aggregation and crystallinity of these polymers may distinctly affect their stability. [ABSTRACT FROM AUTHOR]

The design and development of artificial metal‐free photoenzymes aims to combine the selectivity of enzymatic reactions with the benefits of modern synthetic photocatalysts. Removing the need for rare earth metals and allowing for milder reaction conditions, leading to a more sustainable catalytic system. Here, we present the design of a novel artificial photoenzyme by integrating an organophotocatalytic moiety based on a donor‐acceptor design into a steroid carrier protein (SCP‐2L). SCP‐2L possesses a hydrophobic tunnel facilitating substrate binding in aqueous media. The photocatalyst was site‐selectively bound to three SCP‐2L variants, possessing a non‐native cysteine residue strategically placed around the hydrophobic tunnel of the protein. The three modified photoenzymes were shown to be selective for the oxidation of organic sulfides giving up to 192 turnovers. [ABSTRACT FROM AUTHOR]

The use of inducers of systemic acquired resistance (SAR) is widely described in the literature. Such substances have important advantages over plant protection products (PPPs) and, thus, are often indicated as their alternatives. The main risk indicated in the context of the widespread use of SAR inducers is that of yield reduction that may result from the excessive metabolic imbalance of the treated plant. The general aim of the study presented was to check the effect of using a new active substance, namely N-methoxy-N-methylbenzo(1.2.3)thiadiazole-7-carboxamide (BTHWA), on tulips cultivated in greenhouse conditions. The plant response to BTHWA treatment was also analyzed in terms of the extent to which the growth–immunity phenomena would occur. Surprisingly, the application of BTHWA provided not only efficient protection against fusariosis but also resulted in the stimulation of the growth and development of tomato plants. The results proved very interesting as they stand in contrast to other results on SAR induction. The method of BTHWA application used in this study resulted in SAR induction at a level sufficient to provide effective protection and, at the same time, did not cause disruption to plant metabolism that would result in yield reduction. [ABSTRACT FROM AUTHOR]

In this paper we revisit the fluorescent properties of two fluorophores, namely N‐butyl‐7‐(4‐ methoxyphenyl)‐2,1,3‐benzothiadiazole‐4‐amine (1) and 4‐[[7‐(4‐methoxyphenyl)‐2,1,3‐ benzothiadiazole‐4‐yl]amino]‐benzonitrile (2), whose emissive and fluorescent sensing properties were recently investigated by Peng et al. in Ref. [1]. Experimentally, these two fluorophores were reported to show excitation wavelength‐dependent emission properties, especially 1, which is a dual emitter. The authors of the original manuscript ascribed the excitation‐wavelength‐dependent emission properties to an emission from a higher‐lying excited state (i. e. anti‐Kasha emission). Our investigations, including steady‐state spectroscopy, lifetime measurements and time‐dependent density functional theory and second‐order algebraic diagrammatic construction [ADC(2)] calculations, unambiguously highlight that the fluorophores do not violate Kasha's rule but reveal instead that a protonated species is responsible for the higher‐lying emissive band. In addition, we have elucidated the actual fluorescent pH sensing mechanisms. More and more molecular systems are reported to violate Kasha's rule; sometimes without compelling proof. This study highlights the need to i) exhaustively investigate apparent anomalous cases reported in the literature that seemingly violate Kasha's rule and ii) propose good scientific practices to correctly assign anomalous photochemical events. [ABSTRACT FROM AUTHOR]

Grape berries are one of the most important sources of phenolic compounds, either consumed fresh or as wine. A pioneer practice aiming to enrich grape phenolic content has been developed based on the application of biostimulants such as agrochemicals initially designed to induce resistance against plant pathogens. A field experiment was conducted in two growing seasons (2019–2020) to investigate the effect of benzothiadiazole on polyphenol biosynthesis during grape ripening in Mouhtaro (red-colored) and Savvatiano (white-colored) varieties. Grapevines were treated at the stage of veraison with 0.3 mM and 0.6 mM benzothiadiazole. The phenolic content of grapes, as well as the expression level of genes involved in the phenylpropanoid pathway were evaluated and showed an induction of genes specifically engaged in anthocyanins and stilbenoids biosynthesis. Experimental wines deriving from benzothiadiazole-treated grapes exhibited increased amounts of phenolic compounds in both varietal wines, as well as an enhancement in anthocyanin content of Mouhtaro wines. Taken together, benzothiadiazole can be utilized to induce the biosynthesis of secondary metabolites with oenological interest and to improve the quality characteristics of grapes produced under organic conditions. [ABSTRACT FROM AUTHOR]

Abstract Visible‐light‐driven semiconductor photoelectrodes are promising new devices for on‐demand photocathodic generation of hydrogen peroxide. Herein, the fabrication of organic polymeric photocathodes employing poly(4,7‐di(thiophen‐2‐yl)benzo[c][1,2,5]thiadiazole) (pThBTD), and comparatively seven other related derivatives is reported. The monomer dithienobenzodithiazole can be directly polymerized on an electrode via two methods: electropolymerization or iodine‐vapor‐assisted polymerization. Both give polymers with wide visible light absorption and suitable stability for photoelectrodes. These methods yield different active layer morphologies, with electropolymerization yielding photocathodes with better performance. Critical issues affecting oxygen reduction photocurrents are evaluated, namely thickness, wettability, and pH. Photocathodic oxygen reduction currents, as well as photovoltages, are among the highest reported for an organic photoelectrocatalyst, and pThBTD films can stably produce H2O2 with high faradaic yield over at least 8 h. This study shows that single‐component organic semiconductor devices can be highly competitive versus more complex heterostructures and that such low‐bandgap organic polymers can afford remarkable stability.

Among short donor–acceptor molecules with a central benzothiadiazole fragment, 4,7-di-2-thienyl-2,1,3-benzothiadiazole (T-BTD) is one of the most well-known compounds, valued for its photophysical and semiconductor properties. We have synthesized a derivative of 4,7-di-2-thienyl-2,1,3-benzothiadiazole with trimethylsilyl end-substituents, 4,7-bis(5-(trimethylsilyl)thiophen-2-yl)benzothiadiazole (TMS-T-BTD). The phase transition parameters and thermal stability of T-BTD and TMS-T-BTD were investigated using DSC and TGA methods. The presence of the trimethylsilyl end-groups in TMS-T-BTD significantly enhances solubility, increases the melting temperature, and improves the resistance of TMS-T-BTD to evaporation in the liquid state. Single crystals of T-BTD and TMS-T-BTD were grown from solutions, with the largest sizes being 7 × 2 × 0.5 mm3 and 8 × 1 × 0.45 mm3, respectively. Using single-crystal X-ray diffraction at 293 K, the crystal structure of T-BTD was refined in the rhombic system (sp.gr. Pcab, Z = 8), while for TMS-T-BTD, it was determined for the first time in the monoclinic system (sp.gr. P21/c, Z = 4). The relationship between observed growth anisotropy and molecular packing in the crystals was analyzed. The results of investigations into the spectral-fluorescent properties of solutions in hexane and THF are presented. The solvatochromic effect was studied in a series of solvents, including hexane, THF, dichloromethane, and acetonitrile. The photostability of the compounds in hexane solutions was examined. It was found that the quantum yield of photodestruction for T-BTD is 13 times higher than that of TMS-T-BTD. The fluorescent properties of T-BTD and TMS-T-BTD crystals were investigated.