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This article presents a model that can automatically produce a power amplifier's (PA) design parameters, that is, transmission lines (TLs) dimension, from a dataset of user‐specified design goals like gain, efficiency, linearity, and scattering (S‐) parameters. Based on the applied boundary conditions, a synthetic dataset is generated with the best range of design parameters (W and L). This dataset is utilized for training the physics‐informed neural network (PINN) model with user‐specified design goals as input and design parameters as target to produce the optimum value of W and L as the resultant output. Furthermore, utilizing the obtained dimensions, design, simulation, fabrication, and measurement of a PA are performed to validate our proposed model. The results of large signal measurements of PA are drain efficiency (DE) of 26.9%, power added efficiency (PAE) of 24.7%, output power (Pout) of 30.98 dBm at an input power Pin$$ \left({P}_{in}\right) $$ of 19 dBm, and gain of 12.41 dB at an operating frequency of 1.625 GHz. It has been observed that the design parameters produced by the model have a significant agreement with the validated output. Also, the statistical error analysis is done by calculating the error metrics between the validated output and the actual output of the PA design. [ABSTRACT FROM AUTHOR]

In this paper, behavioral modeling of a driver amplifier is implemented by using S2P and S2D model setup. By using the standard silicon-based driver amplifier for obtaining the measured results of Scattering (S)- parameters and large signal parameters for temperatures 25°C and 85°C. These parameters are imported into the S2P and S2D models to perform the small signal and large signal analysis at 3 GHz frequency for temperatures 25°C and 85°C. Then, the simulated results are compared with the measured results to verify the efficient utilization of behavioral models. The novelty of this work deals with the simulation study of the characteristics of a silicon-based driver amplifier, which are obtained directly from the measurements. This proposed method is essential for performing hetero-integration of transceiver design, which can be further utilized to improve the efficiency of transceiver for high-frequency band. At last, the study of relative error performance analysis between measured and simulated results of different parameters is carried out and calculated value of NMSE (in %) for S11, S12, S21, S22, gain, pout, 1 dB compression point, ACP, 3rd harmonics, 4th harmonics, and 5th harmonics are 0.0083, 0.0055, 0.0086, 0.011, 0.0844, 0.814, 0.926, 0.71, 0.22, 0.012 and 0.070 respectively. [ABSTRACT FROM AUTHOR]

The structural, electronic, and thermodynamical properties of Cn(N3)m (n = 1–7) (m = 4, 6) organic azides have been investigated using Density Functional Calculations. The ground state structures of organic azides were compared with CnHm (n = 1–7) (m = 4, 6) cumulenes which shows their higher relative stability. The stability and reactivity of organic azides were analyzed by calculating the HOMO‐LUMO gap, binding energies, and harmonic frequencies of the azides. The binding energy and formation energy of Cn(N3)m (n = 1–7) (m = 4, 6) organic azides suggest their energetic stability. The structural analysis of the azide group in Cn(N3)m (n = 1–7) (m = 4, 6) organic azide shows a tendency to stabilize at a maximum separation between functional azide groups. Ionization potential, electron affinities, and global hardness have been computed for Cn(N3)m (n = 1–7) (m = 4, 6) organic azides and the odd–even alternation rule was observed. The molecular dynamic simulation performed at 300 K for 1 fs confirms organic azide's structural stability at room temperature, except for C4(N3)4, and the members of their family can be synthesized. [ABSTRACT FROM AUTHOR]

In this paper, a study on the effects of strategically implemented holes in a miniaturized wideband bandpass filter (BPF) utilizing interdigital folded coupled lines is presented. First, the BPF is designed to produce the passband by introducing a fold in the coupled lines. The passband is centered at 9.3 GHz (X‐band), catering to radar applications. Coupled lines connected to a modified U‐shaped transmission line comprise the filter's design configuration. The novelty of the design resides in incorporating drilled holes along the coupled lines, which generate perturbations and resonant effects, resulting in enhanced impedance variations and improved filter performance. With the aid of electromagnetic analysis and simulation software, the coupled lines, U‐shaped transmission lines, and drilled hole diameters are all optimized. Vector Network Analyzer performs all the measurements and draws the comparisons. An increment of 22.58% is seen in return loss as it increases from −24 to −32 dB, and the insertion loss shows an increase of 16.74%. The proposed filter has been subjected to analytical study, simulation, and implementation, which have confirmed its exceptional return loss, favorable insertion loss, and compact dimensions. The research results make a valuable contribution to the development of miniaturized wideband BPFs, specifically focusing on their use in radar systems. In such systems, the ability to accurately and efficiently filter signals is paramount. The design insights and performance improvements presented in this study have significant implications for broader applications in microwave engineering and communication systems. [ABSTRACT FROM AUTHOR]

Here, we have reported a novel deep eutectic solvent (DES) with tremendous activity for the synthesis of dihydropyridines. DESs have played a trio role in the reaction. It acts as a green catalyst, solvent, and in-situ substrate in this chemical reaction. This method offers various advantages such as metal-free catalysis, green solvent, high yields of the products, and short reaction time. [ABSTRACT FROM AUTHOR]

In this article, a study of performing machine learning (ML) based modeling for semiconductor devices has been developed using experimental microwave data. Characterization of gallium arsenide (GaAs) pseudomorphic high electron mobility transistors (pHEMTs) with different gate widths is used as the illustrative example to demonstrate the accuracy and effectiveness of the presented modeling procedure. The tested devices are based on the multifinger layout, in which the total gate width (W) is obtained by multiplying the number of fingers (Nf) and their length (W0). Machines are trained with scattering (S‐)parameter measurements up to 65 GHz by using the extreme gradient boosting (XGBoost) algorithm with K‐fold cross‐validation. Then, the output of the trained machine is utilized by the parameters such as Nf and W0 inside the Auto‐encoder (AE) model. In particular, the ML model with AE has a maximum of 99.88% prediction accuracy, despite the uncertainty inherent in the microwave measurements and the unavoidable deviations from the ideal behavior of the analyzed devices. [ABSTRACT FROM AUTHOR]

[Display omitted] Multidrug-resistant tuberculosis continues to pose a health security risk and remains a public health emergency. Antimicrobial resistance result from treatment regimens that are both insufficient and incomplete leading to the emergence of multidrug-resistant tuberculosis, extensively drug-resistant tuberculosis and totally drug-resistant tuberculosis. The impact of tuberculosis on the people suffering from HIV (Human immunodeficiency virus infection) have resulted in the increased research efforts in designing and discovery of novel antitubercular drugs that may result in decreasing treatment duration, minimising the need for multiple drug intake, minimising cytotoxicity and enhancing the mechanism of action of drug. While many drugs are available to treat tuberculosis, a precise and timely cure is still absent. Consequently, further investigation is needed to identify more recent molecular equivalents that have the potential to swiftly remove this disease. Isoniazid (INH), a treatment for tuberculosis (TB), targets the enzyme InhA (mycobacterium enoyl acyl carrier protein reductase), the Mycobacterium tuberculosis enoyl-acyl carrier protein (ACP) reductase, most common INH resistance is circumvented by InhA inhibitors that do not require KatG (catalase-peroxidase) activation, as a result, researchers are trying to work in the area of development of InhA inhibitors which could help in eradicating the era of tuberculosis from the world. [ABSTRACT FROM AUTHOR]

The Eosin Y photocatalyzed Biginelli protocol has been established by a cascade one-pot three-component reaction of primary alcohols, α-ketoester, and urea to provide pharmacologically promising 3,4-dihydropyrimidin-2(1H)-ones in high yields. The key benefits of the present scheme are the capability to allow operational simplicity, readily available substrates, straightforward workup and high yields. This Eosin Y based photocatalytic approach can permit conquering traditional metal-catalyzed reactions in a sustainable manner, thus delivering economic and environmental rewards. An environmentally benign protocol for the synthesis of 3,4-DHPMs has been developed using inexpensive molecular oxygen, visible light as green energy source and eosin Y as photoreceptor-cum-sensitizer. The utilized photoreceptor revealed its unique properties in rapid intersystem crossing, high photo and chemical stability, ease of separation and high catalytic efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] • This review highlights the Light-promoted methodologies for the oxidation of alcohols. • Different photocatalysts like MOF-hybrids, metal hybrids, metal oxides, and metal free catalysts are discussed. • This study includes the critical analysis of the different reports along with comparative account. Light-promoted methodologies can be considered ideal protocols for green and environment-friendly oxidation of alcohols, unlike many traditional methods and reagents that are toxic, hazardous, and low-yielding with tedious work up. The visible-light-induced photo redox catalysis to produce radical species has a broad scope in the selective oxidation of alcohols into their carbonyl compounds that have a broad application in industries and synthetic chemistry. In this comprehensive review, we targeted articles focused on photocatalytic transformations of primary aromatic alcohols to respective aldehydes. The photoconversion of alcohols into aldehydes was accelerated by MOF-hybrids, metal hybrids, metal oxides, and metal free catalysts. Overall, the present manuscript involves the different aspects of light promoted oxidation reactions of aromatic alcohols employing varied photocatalysts. This study also includes the critical analysis of the different reports available along with comparative account. [ABSTRACT FROM AUTHOR]

Click chemistry, involving carbon-hetero bond formation, is gaining global attention due to its high reaction rate, good functional-group tolerance, and high product yield. Click chemistry has effectively demonstrated its broad variety of applications in numerous disciplines that are helpful to mankind. Most crucially, click chemistry has made it feasible to synthesize different fluorescence emitting polymers, bioimage essential biomolecules, detect dangerous ions, and visualize cancer and other different cell lines. Additionally, the adaptability of 1,2,3-triazole-containing molecules as pharmaceutically active substances has made it possible to synthesize a variety of 1,2,3-triazole-containing medicinal compounds with good product yield and under mild reaction conditions. Today's click chemistry has helped scientists in fluorescence imaging, one of the most popular and successful methods for studying the quantitative behavior of biomolecules in living cells, tissues, and animals. Furthermore, click chemistry's straightforward methodology and quick incubation time period have made Cu(II) detection conceivable as an on-site testing procedure. As a result, the study intends to cover a variety of click chemistry applications in order to aid scientists in their future research. [Display omitted] • Approach of click chemistry discussed. • Synthesis of fluorescent materials by click chemistry. • Click chemistry in the detection of Cu(II) ions. • Applications of Click chemistry in bioimaging. [ABSTRACT FROM AUTHOR]

3-Butadienyl-β-lactams are useful organic synthon which have efficiently been explored for the synthesis of a variety of heterocyclic systems. The present review compiles the various reports on the synthesis of 3-butadienyl-β-lactams and their explorations in the development of variety of monocyclic as well as condensed heterocyclic systems. [ABSTRACT FROM AUTHOR]

A multifunctional self-assembled dual-chemosensor DTS was synthesized and used for optical and microstructural based discrimination of Hg 2+ , CN − ions and Hg(CN) 2 ion-pair. The addition of Hg 2+ ions to the CH 3 CN solution of DTS promotes the ESIPT phenomena (emission peak at 458 nm red shifted to 510 nm; increase in absorption between 400 and 480 nm), followed by cyclization (guanylation) reaction with concomitant desulfurization (decrease of emission intensity at 510 nm and minor increase at 410 nm; increase and decrease in absorbance intensity at 270 and 325 nm, respectively). In contrast, CN − induced deprotonation in DTS results in simultaneous decrease in absorbance at 310 nm and increase in absorbance at 385 nm and 425–475 nm and fluorescence enhancement at λ em 452 nm. On the addition of Hg(CN) 2 ion pair, DTS shows apparent effect of both Hg 2+ and CN − ions. The mechanism of interaction of DTS with Hg 2+ , CN − and Hg(CN) 2 has been established by detailed 1 H NMR and ESI–MS studies. DTS in CH 3 CN shows flake like morphology which undergoes analyte induced self-assembly to form a bunch of nanorods with Hg 2+ ; segregated nanorods with curvy ends with CN − and spherical structures with Hg(CN) 2 ion pair. [ABSTRACT FROM AUTHOR]

We report the synthesis of perylenediimide (PDI)-based donor-acceptor hybrids through dissymmetric bay functionalization of PDIs. The dissymmetric bay-functionalized di- and trisubstituted PDIs were characterized by using one- and two-dimensional NMR spectroscopy. Density functional theory calculations revealed (i) an energy gap between the HOMO and LUMO in the range 2.14-2.34 eV, beneficial for charge-transfer properties; and (ii) a twist angle between the two naphthalene units in the range 17-26°, which might be beneficial for disruption of co-facial stacking of the PDI. [ABSTRACT FROM AUTHOR]

The present methodology explored the effectiveness and versatility of deep eutectic solvent with ultrasonic energy as an eco-friendly protocol for the synthesis of bisthioglycolic acid derivatives. Bisthioglycolic moiety holds its role as a potent scaffold in sulfur-containing drugs. The presented strategy offers significant advantages such as green catalyst as well as solvent, excellent yield, short reaction time, and simple reaction workup. This methodology shows a wide range of substrate scope that contain both electron-donating as well as electron-withdrawing groups. [ABSTRACT FROM AUTHOR]

Control over the self-assembly of bay functionalized perylene diimides and the response of these self-assembled materials towards analytes in mixed aqueous–organic media is important to consider the potential of this intriguing dye family in supramolecular chemistry. Herein, we have designed and synthesized allylcarbonate-functionalized perylene diimide AC-PDI which shows solvent dependent supramolecular nanostructures and could readily self-assemble into nanorods of tens of μm in length in CH3CN, but the length of the rods drammatically decreased to 0.8–1.2 μm in a H2O : CH3CN (1 : 1, v/v) mixture. Interestingly, AC-PDI self-assembles into nanowires of several tens of μm in length in a 30% H2O:DMSO mixture and forms only nanospheres in ethyl acetate. AC-PDI can be used as a near-infrared (NIR) colorimetric (λabs 685 nm) and fluorescent (λem 530/570 nm) probe for selective detection of Pd0 [LOD = 39 nM (UV); 45 nM (FI)]. Furthemore, TLC strips coated with the AC-PDI probe could detect 0.58 pg cm−2 of Pd0 in the solid state. The mechanism of interaction of AC-PDI with Pd0 has been confirmed by 1H NMR titration, kinetic and morphological studies. [ABSTRACT FROM AUTHOR]

Abstract: A novel, efficient and one‐pot multicomponent copper‐catalyzed amination of N‐pyridyl imines is described. This, one‐pot, multicomponent reaction, in which imine acts as a directing group by chelating to the metal core, affords a domino approach for the transformation of the commercial pyridinamines, aldehydes and azide into valuable imidazo[4, 5‐b]pyridines with wide substrate extent and diversity. [ABSTRACT FROM AUTHOR]

Abstract: The regioselective nitroso Diels–Alder (NDA) cycloadditions of 3-dienyl-2-azetidinones with nitrosobenzene to generate oxazine-substituted β-lactams in excellent yields are reported. The amidiolytic ring opening of the cycloadducts with sodium methoxide followed by iodocyclization using I2/K2CO3 etiquette to capitulate previously unknown, multisubstituted pyrroloxazine in outstanding yields is also accounted. [Copyright &y& Elsevier]

Abstract: The regio-, diastereo-, and π-facial selective Lewis acid mediated Diels–Alder reactions of cis/trans-3-butadienyl-2-azetidinones with unsymmetrical dienophiles viz. methyl acrylate, dimethyl fumarate, and acrolein leading to the synthesis of diastereomerically pure and biologically potent 1,3,4-trisubstituted-2-azetidinones are reported. Theoretical calculations at HF/6-31G∗∗ and 6-31G∗∗/DFT levels have been performed to support the observed π-facial selectivity. The formation of diastereomerically pure ‘endo’ adducts is supported by the X-ray diffraction studies. [Copyright &y& Elsevier]

The chemo- as well as regioselective participation of N-aryl imines as 4π component in aza-Diels-Alder reactions with 3-butadienyl-2-azetidinones in the presence of Lewis acid catalysts resulting in novel quinoline derivatives is described. [ABSTRACT FROM AUTHOR]

The chemo- as well as regioselective participation of N-aryl imines as 4? component in aza-Diels-Alder reactions with 3-butadienyl-2-azetidinones in the presence of Lewis acid catalysts resulting in novel quinoline derivatives is described. [ABSTRACT FROM AUTHOR]

Abstract: The chemo- as well as regioselective imino Diels–Alder reactions of 5-dienyl pyrimidinones with N-aryl as well as N-naphthyl imines in the presence of a different Lewis acid catalysts resulting in novel quinoline and benzoquinoline derivatives are reported. [Copyright &y& Elsevier]

Abstract: The chemo- as well as regioselective aza Diels–Alder reactions of 5-dienyl pyrimidinones with N-arylimines in the presence of a Lewis acid catalyst resulting in novel quinoline derivatives are reported. [Copyright &y& Elsevier]

Abstract: A facile single step synthesis of novel azocinone derivatives involving tandem [2+2] cycloaddition and Cope rearrangement in the reactions of cross-conjugated azatrienes with vinyl/isopropenyl ketenes supported by theoretical calculations is reported. [Copyright &y& Elsevier]

This paper presents novel via-only bandpass filters for a wide range of microwave/millimeter-wave frequencies. The design is based on rigorous field-theory analysis of a dielectric-loaded inductive-iris waveguide section combined with an impedance-inverter-based filter synthesis to realize maximally flat or Chebyshev characteristics. The new filter configurations are simple to realize, easy to fabricate, and highly suitable for LTCC and organic technologies. This study is carried out in order to examine the effect of the placement of continuous vias replacing the conducting side walls in iris-waveguide filters. Three bandpass filters in the new configuration are designed at center frequencies of 10, 14, and 29 GHz for the X, Ku, and Ka bands, respectively. For all the designs, the theoretical responses have been validated with commercially available full-wave electromagnetic simulation software. Since the design methodology is based on rigorous full-wave field-theory analysis, the proposed technique offers a high degree of accuracy. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 215–218, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21127 [ABSTRACT FROM AUTHOR]

Abstract: The present Letter describes the use of β-lactams for the synthesis of functionalized β-amino esters and their transformation to trisubstituted octahydroisoquinolone derivatives in good yields with an extension to their one-pot synthesis. [Copyright &y& Elsevier]

We report a Pd-catalyzed intramolecular [3C + 2C + 2C] cycloaddition between alkylidenecyclopropanes, alkynes and alkenes. The method provides synthetically relevant 5-7-5 tricyclic structures, with good chemoselectivity and complete diastereoselectivity. [ABSTRACT FROM AUTHOR]

Abstract: The regioselective aza Diels–Alder reactions of isopropenyl pyrimidinone with N-arylimines in the presence of Y/Sc triflates as catalyst are described. An unprecedented oxidation of methylene to carbonyl occurred resulting in exclusive formation of 6-oxo-1,6-dihydropyrimidin-5-yl-4H-quinolin-3-one derivatives. [Copyright &y& Elsevier]

The manuscript presents an efficient method for the synthesis of various cis-azetidin-2-ones with high regio- and diastereoselectivity. This approach utilizes Kinugasa reaction involving diverse functionalized nitrones, including diaryl nitrones and α,β-unsaturated nitrones, in conjunction with acetylenic alcohols. Copper (I) serves as a catalyst to facilitate the transformation. [ABSTRACT FROM AUTHOR]

A safer, greener, and more effective reaction methodology for the synthesis of dihydroquinazolinones (DHQs) has been developed. The deep eutectic solvent (DES) ZnCl2/urea employed in this study efficiently accelerated the cyclization of 2‐aminobenzamide with different aldehydes (aromatic and heteroaromatic) to afford the target scaffolds without the generation of any oxidized product. This method has exhibited remarkable advantages such as quick reaction time, mild reaction conditions, high yield (82%–98%), operational simplicity, and selectivity. The approach was observed to be tolerant to electron‐donating and electron‐withdrawing functional groups. Green metric parameters (AEf, OE, AE, RME, CE, etc.) determined further aided this greener chemical approach. [ABSTRACT FROM AUTHOR]

Pyrrolin‐4‐ones/pyrrolin‐3‐ones and its derivatives are important heterocyclic systems which are observed in vast variety of natural products, pharmaceuticals, and biologically important compounds. Different researchers all across the world have developed different synthetic methodologies for the construction of functionalized pyrrolin‐4‐ones/pyrrolin‐3‐one scaffolds such as the transition‐metal catalyzed/mediated cycloisomerizations of 1‐aminoynones and dimerization of enaminones or α‐diazo‐β‐oxoamides etc. The present review article summarizes various reports on the synthesis of various simple and functionalized pyrrolin‐4‐ones/pyrrolin‐3‐ones from 2000 onward. [ABSTRACT FROM AUTHOR]

Abstract InhA is an enoyl acyl carrier reductase that catalyzes the chemo-selective reduction of its 2-trans-enoyl-ACP substrate. The pharmacological effects of the frontline medications used in the treatment of tuberculosis are elicited by inhibiting the enzyme InhA, which disrupts the mycolic acid biosynthesis pathway. The present study involves development of ligand-based pharmacophore model, docking studies, generation of 3D-QSAR model, and molecular dynamic simulation studies of virtually screened putative InhA inhibitors. The best field-based 3D-QSAR model was validated using partial least-square regression (PLS) method with high regression coefficient for training set (R 2) = 0.9256 and test set (R 2) = 0.7542, cross-validated coefficient (r cv 2) = 0.72 and R 2 pred = 0.9764. Also, virtual screening yielded compounds 4, 25, 1, and 30 exhibiting appreciable interactions (docking scores −5.972, −3.819, −3.801, and −3.701, respectively with InhA synthetase; PDB ID: 1BVR). Further, ADMET studies supported drug-like potential of compounds 25, 1, and 30 whereas compound 4 showed negligible human oral absorption. The molecular dynamic simulation studies of the top scored molecule 25 suggested stability of 25-1BVR complex over the course of simulation run. Therefore, this work can be helpful for future discovery of novel InhA inhibitors against drug-resistant tuberculosis. [ABSTRACT FROM AUTHOR]

Abstract The reported work presents the diastereo, regio-, and π-facial selective synthesis of hetero-Diels-Alder (H-DA) cycloadducts with diazene derivatives viz. di-isopropyldiazocarboxylate and diethylazodicarboxylate with cis-/trans-3-butadienyl-β-lactams having stereocentres at its α and β-position. The H-DA reactions resulted in the formation of β-lactam tethered—3,6-dihydro-pyridazines in good yields. [ABSTRACT FROM AUTHOR]

Fluorescent molecules are extensively employed in (bio)sensing and bioimaging but their applications in the visualization of fingerprints are less reported due to their inherited aggregation-caused quenching (ACQ) mechanism in the solid state (aggregated form). DPSA undergoes self-assembly to form aggregates with rod-like structures in a 90% H2O : CH3CN mixture evident from dynamic light scattering (DLS) and scanning electron microscopic (SEM) techniques. The self-assembled diphenylpyrimidinone (DPSA) derivative shows aggregation-induced emission (∼24 fold) in a ＞90% H2O : CH3CN mixture with orange-red fluorescence (λmax 564 nm). The red fluorescent aggregates of DPSA show applications in the visualization of latent fingerprints on aluminium, stainless steel and metal currency coin substrates. In addition, we established the individuality of three subjects based on information gathered at level one (pattern of arch, loop or whorl) and level two (minutiae details of dots, bifurcation, ridge ending, core and delta). [ABSTRACT FROM AUTHOR]

Abstract: Here in, novel excited state intramolecular charge transfer (ESIPT)‐modulated fluorophore based on diphenylpyrimidinone DPHQ has been designed and synthesized. DPHQ shows selective 8‐fold ‘turn‐on’ fluorescence response with Cd2+/Zn2+ in buffer (containing 1% CH3CN, pH 7.2) with low detection limits of 55.7/2.7 nM accompanied with a fluorescent colour change from colourless to cyan. DPHQ–Cd2+ ensemble undergo selective fluorescence quenching with nucleoside triphosphates but it is silent to nucleoside di‐and mono‐phosphates. It can detect 58.4 nM concentration of adenosine triphosphate (ATP). The binding mode and sensing mechanism of DPHQ with Cd2+/Zn2+ was supported by the change in optical behaviors, density functional theory (DFT) calculations and Job's plot. DPHQ was successfully used for construction of ‘Set‐Reset’ memorized logic devices and OR, INHIBIT logic gates. As practical applications of DPHQ, we utilized DPHQ for detection of Cd2+/Zn2+ in blood serum and quantification of Zn2+ in tap water samples. [ABSTRACT FROM AUTHOR]

Unimolecular system SBU shows multiple output responses on interaction with Cu 2+ /F − ions individually and simultaneously. The complexation of Cu 2+ with imine ( C N) and OH groups results in blue-shift from 332 to 303 nm and de-protonation of OH group with F − ions causes red-shift of the absorption maxima from 332 to 405 nm. The addition of F − to SBU∩Cu 2+ solution or addition of Cu 2+ to SBU∩F − solution shifts the absorption maxima from 303 to 374 nm or 405–303 nm, respectively. Similarly, the complexation of Cu 2+ ions, inhibits the ESIPT emission at 512 nm with concommitant release of emission at 425 nm, whereas F − results in quenching of emission at 512 nm up to 10 μM, followed by blue-shift to 425 nm at >10 μM F − ions. The addition of F − to SBU∩Cu 2+ solution causes quenching of emission at 512 and 425 nm, whereas addition of Cu 2+ to complex SBU∩F − solution revives the emission at 425 nm considerably. These multiple output response leads to elaboration of YES, NOT, NOR, INH, AND, XOR and XNOR logic gates and Half-adder, Half-subtractor, 2-to-4 decoder, 1:2 demultiplexer, Magnitude Comparator, complimentary OR/NOR circuit and molecular keypad lock logic circuits. [ABSTRACT FROM AUTHOR]

The detection and quantification of spermine in clinical practice is important for early diagnosis of many diseases. Chromatographic and immunoassay-based methods are commonly used. However, a fluorescence-based assay could provide real-time detection. Herein, the synthesis and aggregation properties of a dicationic perylene probe ( N1-dodecyl- N3-(4-phenyl)benzimidazolium-functionalized perylenediimide ( DAB-PDI)) used to develop a fluorescent 'turn-on' ensemble for the detection of spermine are discussed. The fluorescence of DAB-PDI (10 μ m, Φ=0.55) is efficiently quenched by negatively charged sodium dodecylsulfate (SDS) through the formation of ionic self-assembled aggregates (charge ratio of negative (N) in SDS to positive (P) in DAB-PDI (N/P)=9). This negatively charged ionic self-assembly between DAB-PDI and SDS has been characterized by using photophysical, microscopic, dynamic light scattering, isothermal titration calorimetry, and HRMS techniques. The addition of spermine to this ensemble solution results in the breakdown of the DAB-PDI-SDS ensemble owing to strong binding of spermine with SDS and, as a result, the fluorescence of DAB-PDI is recovered. This ensemble exhibits high sensitivity and selectivity for spermine detection in water, urine, and blood serum. The lowest limit of detection is 27.5 n m, which is at least about 36 times lower than that required for early diagnosis of cancer (1 to 10 μ m for urinary spermine). [ABSTRACT FROM AUTHOR]

The manuscript describes a facile and highly diastereoselective synthesis of cis-3-(hydroxy/bromo)methyl-1-aryl-4-(-styryl)azetidin-2-ones via copper(i) mediated Kinugasa reactions of previously unexplored functionalized α,β-unsaturated nitrones. A variety of functionalized acetylenes and α,β-unsaturated nitrones were studied to yield cis-3-(hydroxy/bromo)methyl-1-aryl-4-(-styryl)azetidin-2-ones in good yields (82%). [ABSTRACT FROM AUTHOR]

A green, sustainable, and efficient one-pot, synthetic strategy for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones (DHQs) was developed. The ZnCl2/urea used as a deep eutectic solvent (DES) not only efficiently promoted the condensation between isatoic anhydride and benzaldehyde but unexpectedly acted as a nitrogen source (like ammonia) in situ to afford DHQs in excellent yields. This approach offers remarkable advantages, involving the triple role of DES in the synthesis of DHQs, atom-economical, green organocatalysts, metal-free conditions, cost-effectiveness, and tolerance to a range of functional groups. [ABSTRACT FROM AUTHOR]

Highly diastereo- and π-facially selective imino Diels–Alder cycloadditions of 3-allylideneamino-2-azetidinones having stereocentres at its α- and β-positions, with symmetrical dienophiles leading to the formation of biologically potent (2-oxo-4-styrylazetidin-3-yl)–pyridine hybrids have been reported. [ABSTRACT FROM AUTHOR]

An eco-friendly, easily achievable and efficient strategy has been explored to synthesize functionalized bisthioglycolic acids using a variety of aldehydes and thioglycolic acid. The employed protocol is solvent free and provides the desirable products in excellent yields (90–99%) with atom economy. Besides, cost effectiveness, short reaction times and milder reaction conditions are among other captivating benefits of the reported methodology. [ABSTRACT FROM AUTHOR]

Abstract: Cu(I)Cl promoted synthesis of N-propargylated-isatin Mannich mono- and bis-adducts with an extension towards the synthesis of N-propargylated-isatin-7-chloroquinoline conjugates was described. The synthesized scaffolds were evaluated for their in vitro activity against the veterinary protozoal pathogen Tritrichomonas foetus and cytotoxicity against human prostate (PC-3) cancer cell line. The preliminary evaluation data revealed the enhancement in the activity profiles with the introduction of 7-chloroquinoline ring with the most active conjugates 7a, 7c and 7d exhibiting an IC50 of 22.2, 11.3 and 24.5 μM respectively against T. foetus and minimal toxicity against human prostate (PC-3) cell lines. [Copyright &y& Elsevier]

Abstract: A convenient and unprecedented synthesis of functionally enriched octahydroindole-based scaffolds has been developed via inter- and intra-molecular amidolysis of C-3 functionalized β-lactams. The cytotoxic evaluation on oesophageal cancer cell line WHCO1 has revealed 7d as the most potent of the test compounds exhibiting an IC50 value of 12.97μM. The developed strategy further assumes significance as it entails the preparation of highly functionalized indoles without the aid of transition metal catalysis or pre-functionalization of substrates. [Copyright &y& Elsevier]

Polymeric membrane electrodes (PMEs) and coated graphite electrodes (CGEs) containing 1,3,4-trisubstituted-2-azetidinone derivatives as ion carriers are reported here for bismuth(III) ion selectivity. These electrodes exhibited Nernstian response for Bi3+ ions over a wide concentration range (5.0 × 10-7 M to 1.0 × 10-1 M for CGE) with a lower detection limit of 3.98 × 10-7 M (for CGE) and wide pH range (1.3-5.0). Compared to polymeric membrane electrode, the coated graphite electrode has shown better selectivity for Bi3+ ions with respect to common metal ions. Proposed electrodes have been used for the estimation of Bi3+ ions in pharmaceutical and glass samples. [ABSTRACT FROM AUTHOR]

Functionalized tricyclicpyrimidinones, a class of condensed heterocyclic systems, are found in numerouspotentially active molecules having both innate as well as synthetic origin. Different researchers across the world have explored different synthetic methods for the construction of appropriately functionalized tricyclicpyrimidinones. The present review article recapitulates various reports pertaining to substituted and functionalized tricyclic pyrimidinones reported since 2000. [ABSTRACT FROM AUTHOR]

The manuscript describes an efficient, atom economical synthesis of pyrimido[4,5-b][1,4]benzodiazepin-4-ones by relatively unexplored 7-endo-trig Pictet–Spengler type cyclisations. The synthetic methdodlogy involves the synthesis of different variants of 5-arylidene-amino-3H-pyrimidines and their p-toluene sulfonic acid mediated 7-endo-trig Pictet–Spengler type cyclisations to afford biologically relavent functionalized benzodiazepine condensed pyrimidinones such as pyrimido[4,5-b][1,4]benzodiazepines in good to excellent yields (82–94%). [ABSTRACT FROM AUTHOR]

Abstract: Assisted by PASS predictions, the antidepressant activity of 1,3,4-trisubstituted monocyclic β-lactams in seasonal affective disorders is described. [Copyright &y& Elsevier]

Rhodium-catalyzed intermolecular [3 + 2+2] cycloaddition reactions of bis(methylenecyclopropanes) with different alkynes are described. The rhodium-catalyzed [3 + 2+2] cycloadditions resulted in the formation of functionalized 5–7–3 spirocyclic carbocycles in moderate yields with excellent regio- and chemo-selectivity. [ABSTRACT FROM AUTHOR]

A nickel(0)-catalyzed intermolecular [3+2] cycloaddition of bis(alkylidenecyclopropanes) with diazenes such as diethyl or diisopropyl azodicarboxylate gave pyrazolidine-1,2-dicarboxylates in moderate to good yields (61–72%). [ABSTRACT FROM AUTHOR]

Graphical abstract Self-assembled fibre-to-disc fluorescent aggregates of coronene diimide were explored for tuning of their emission color, visualization of latent fingerprints (solution and powder dusting methods) and bio-labeling of HeLa cells. Highlights • Two novel coronene diimides have been synthesized. • Controlled transformation of fibre-to-disc-like aggregates alongside tuning of their emission color has been achieved. • Red fluorescent aggregates of CDI 3 show application in visualization of latent fingerprints. • For the first time CDI 3 were used in powder dusting method to visualize the latent fingerprints on porous surfaces. • CDI 3 was also explored for bio imaging of HeLa cells. Abstract Coronenediimide (CDI 3) forms long fibrillar nanostructure when dissolved in DMF. On addition of >70% water in DMF, CDI 3 undergo fibre-to-disc morphological transformation alongside onset of different emission colors in water-DMF binary mixtures. These self-assembled red emitting aggregates of CDI 3 applied for visualization of latent fingerprints using solution spray and powder dusting methods on porous and non-porous surfaces commonly found in home such as aluminium, stainless steel, glass, metal coins, compact discs (CDs), OHP films, ceramic tiles and paper sheets. In an attempt to explore the application of CDI 3 in the forensic cases, 2nd level of information was used for distinguishing different fingerprints from different subjects. These disc-like fluorescent red aggregates of CDI 3 were also used for staining of HeLa cells. [ABSTRACT FROM AUTHOR]

We report Pb2+-mediated interlocked hexagonal self-assembly associated with the near-IR (660 nm) ‘turn-on’ detection of Pb2+ ions (LOD = 25 nM) in water using a perylene diimide derivative (PDI-HQ). The PDI-HQ–Pb2+ complex was further used to develop a fluorescent NIR ensemble for the detection of thiols. [ABSTRACT FROM AUTHOR]