Recent progress of nanocatalyst in the synthesis of heterocyclic compounds by barbituric acids

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Recent progress of nanocatalyst in the synthesis of heterocyclic compounds by barbituric acids

Heterocycles and barbituric acid analogs are particularly used in developing and designing new drugs because of their versatile binding properties for different biotargets. They are present in many natural compounds, vitamins, drugs, and biologically active molecules such as anticancer, antibiotic, antidiabetic, anti-inflammatory, antidepressant, anti-HIV, antimicrobial, and insecticidal agents. Using co-friendly techniques under nanocatalyst conditions drives the synthesis of these bioactive compounds toward green chemistry. This review will investigate the nanocatalysts, including magnetic nanocatalysts, nano metal-based catalysts, organo-nanocatalysts, and metal–organic frameworks (MOFs) nanocatalysts employed in the synthesis and design of heterocyclic compounds by barbituric acids from 2017 to 2022.


Heterocycles and barbituric acid analogs are particularly used in developing and designing new drugs because of their versatile binding properties for different biotargets. They are present in many natural compounds, vitamins, drugs, and biologically active molecules such as anticancer, antibiotic, antidiabetic, anti-inflammatory, antidepressant, anti-HIV, antimicrobial, and insecticidal agents. Using co-friendly techniques under nanocatalyst conditions drives the synthesis of these bioactive compounds toward green chemistry. This review will investigate the nanocatalysts, including magnetic nanocatalysts, nano metal-based catalysts, organo-nanocatalysts, and metal–organic frameworks (MOFs) nanocatalysts employed in the synthesis and design of heterocyclic compounds by barbituric acids from 2017 to 2022.

Novel Triangulenes: Computational Investigations of Energy Thresholds for Photocatalytic Water Splitting

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Organic materials with Inverted Singlet-Triplet (INVEST) gaps are interesting for their potential use as photocatalytic small molecule transformations, like the entirely solar-driven water splitting reaction. However, only few INVEST emitters are thermodynamically able to split water, with first singlet excited states, S1, above 1.27 or 1.76 eV; and absorbing near solar maximum, 2.57 eV. These requirements and the INVEST character are key for achieving long-lived photocatalyst for water splitting. The only known INVEST emitters that conform to these criteria are large triangular boron carbon nitrides, with unknown synthesis pathways. With quantum-mechanical calculations using ADC(2), we describe three triangulenes. 3a is a cyano azacyclopenta[cd]phenalene derivative while 3b and 3c are cycl[3.3.3]azine derivatives. 3b has a previously undescribed disulfide bridge. Overall 3a fulfills requirements for photocatalytic four-electron reduction of water while the S1 states of 3b and 3c are likely slightly low for the two-electron reduction process. By analyzing impacts of ligands, we find that there are guidelines describing how S1-S5 energies and oscillator strengths, T1 energies and ΔES1T1 gaps are affected, requiring deep-learning algorithms for which studies will be presented by us in due time. The impact of solvation effects as well as reduced-cost ADC(2) algorithms on our findings are discussed.

Functional Polymers as Artificial Solid Electrolyte Interface for Stabilizing Lithium Metal Anode

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The practical implementation of the lithium metal anode (LMA) has long been pursued due to its extremely high specific capacity and low electrochemical equilibrium potential. However, the unstable interfaces resulting from lithium ultrahigh reactivity have significantly hindered the use of LMA. This instability directly leads to dendrite growth behavior, dead lithium, low Coulombic efficiency, and even safety concerns. Therefore, artificial solid electrolyte interfaces (ASEI) with enhanced physicochemical and electrochemistry properties have been explored to stabilize LMA. Polymer materials, with their flexible structures and multiple functional groups, offer a promising way for structurally designing ASEIs to address the challenges faced by LMA. This Concept demonstrates an overview of polymer ASEIs with different functionalities, such as providing uniform lithium ion and single-ion transportation, inhibiting side reactions, possessing self-healing ability, and improving air stability. Furthermore, challenges and prospects for the future application of polymeric ASEIs in commercial lithium metal batteries (LMBs) are also discussed.

Stimuli‐Responsive and Multifunctional Nanogels

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Nanogels represent promising drug delivery systems in the biomedical field, designed to overcome challenges associated with standard treatment approaches. Stimuli-responsive nanogels, often referred to as intelligent materials, have garnered significant attention for their potential to enhance control over properties such as drug release and targeting. Furthermore, researchers have recently explored the application of nanogels in diverse sectors beyond biomedicine including sensing materials, catalysts, or adsorbents for environmental applications. However, to fully harness their potential as practical delivery systems, further research is required to better understand their pharmacokinetic behaviour, interactions between nanogels and bio distributions, as well as toxicities. One promising future application of stimuli-responsive multifunctional nanogels is their use as delivery agents in cancer treatment, offering an alternative to overcome the challenges with conventional approaches. This review discusses various synthetic methods employed in developing nanogels as efficient carriers for drug delivery in cancer treatment. The investigations explore, the key aspects of nanogels, including their multifunctionality and stimuli-responsive properties, as well as associated toxicity concerns. The discussions presented herein aim to provide the readers a comprehensive understanding of the potential of nanogels as smart drug delivery systems in the context of cancer therapy.

Tumor‐pH‐value responsive non‐peripheral substituted phthalocyanines: Synthesis, investigation of photophysical and photochemical properties

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Tumor-pH-value responsive non-peripheral substituted phthalocyanines: Synthesis, investigation of photophysical and photochemical properties


Cancer is one of the diseases with the highest mortality rate worldwide. Although PDT has recently produced encouraging outcomes, there are still many areas that need to be improved. The first of these is the negative consequences faced by patients treated with the PDT method when exposed to sunlight. For this reason, a new PDT method has been developed in recent years, and it is aimed at using photosensitizer molecules that can be active in acidic conditions. Since the pH values of tumor tissues are more acidic than normal tissues, preparing molecules that act effectively in acidic conditions will allow for more effective results in treating cancer with PDT. In this context, within the scope of this study, 3-(4-propionylphenoxy)phthalonitrile (1) and its non-peripheral tetra-substituted phthalocyanine derivatives [(2), (3), and (4)] were prepared. With these phthalocyanine derivatives, the novel compounds (5), (6), and (7) were synthesized for the first time. The aggregation tendencies of newly synthesized phthalocyanines (5–7) were investigated in solvent media. The effects of pH changes upon UV–Vis and fluorescence spectra were performed. The electronic and emission spectra of synthesized phthalocyanine derivatives are highly sensitive to pH changes. Formation constant (LogK) values of mono- and di-protonated phthalocyanine forms were calculated by the Henderson–Hasselback equation. The mono- and di-protonated species' equilibrium constants (logK1 and logK2) were calculated as ~5.0. This value may be promising for pH-sensitizing photosensitizers. Also, the photophysical and photochemical properties of synthesized metallophthalocyanine derivatives (2) and (5) were studied at different pH values. The singlet oxygen quantum yield of (2) and (5) was calculated to be 0.78 and 0.81 in DMSO, respectively. When pH = 6.4, that is, tumor-pH-values, this value for (5) has increased to 0.92. The newly synthesized phthalocyanines are suitable photosensitizers for PDT applications, especially with high singlet oxygen quantum yield at pH 6.4.

Theoretical insights into photo‐induced behavior for 3‐(1H‐phenanthro[9,10‐d]imidazol‐2‐yl)‐9‐phenyl‐9H‐carbazol‐4‐ol fluorophore: Solvation effects

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Theoretical insights into photo-induced behavior for 3-(1H-phenanthro[9,10-d]imidazol-2-yl)-9-phenyl-9H-carbazol-4-ol fluorophore: Solvation effects

Photo-induced excitation enhances intramolecular hydrogen bonding interactions for CHPHI compound. Enhanced hydrogen bond OH⋯N facilitates ESIPT tendency. ICT further promotes the occurrence of ESIPT reaction for CHPHI system. Nonpolar solvent environment is more favorable for ESIPT behavior of CHPHI fluorophore.


Abstract

Excited-state intramolecular proton transfer (ESIPT) reaction, as one of the most fundamental photochemical behaviors, plays a crucial role in the design of novel optical materials. This study investigates the photo-induced hydrogen bonding behaviors and related ESIPT process of 3-(1H-phenanthro[9,10-d]imidazol-2-yl)-9-phenyl-9H-carbazol-4-ol (CHPHI) in solvents with varying polarities. Based on analyses of the core-valence bifurcation (CVB) index, geometrical structure parameters, topological analysis, and infrared (IR) vibrational spectra, we infer that light excitation facilitates the enhancement of intramolecular hydrogen bonding. This phenomenon can promote the ESIPT process. In particular, we have observed that the enhancement of hydrogen bonding becomes more pronounced as solvent polarity weakens. To further investigate the relationship between solvent polarity and ESIPT behavior, we conduct an exploration of the frontier molecular orbitals (MOs) in CHPHI. Finally, by comparing the magnitudes of excited-state barriers in different solvents, we claim that nonpolar solvents drive the ESIPT reaction for CHPHI fluorophore.

Bubble Interfacial Area in a Swirling Contactor: Experiments and Computational Fluid Dynamics Simulations

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Bubble Interfacial Area in a Swirling Contactor: Experiments and Computational Fluid Dynamics Simulations

Swirling flows can be applied for gas-liquid mass transfer process intensification. Experiments and simulations were conducted to investigate the bubble size, gas holdup, and interfacial area in a swirling contactor which was divided into twelve subregions. Bubble breakup and coalescence processes between all bubble size classes were considered using appropriate models.


Abstract

The bubble size, gas holdup, and interfacial area in a swirling contactor were investigated through experiments and simulations. The interfacial area was obtained for liquids and gases with Reynolds numbers Re l and Re g, respectively. The contactor was divided into twelve subregions. Re l was negatively related to bubble size, gas holdup, and interfacial area, whereas Re g was positively associated. The maximum bubble interfacial area for the entire swirling contactor was 196.3 m−1 with a gas-liquid ratio of 0.022. There is a trade-off between centrifugal acceleration and bubble size for interfacial area.

Piper chaba, an Indian spice plant extract, inhibits cell cycle G1/S phase transition and induces intrinsic apoptotic pathway in luminal breast cancer cells

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Abstract

Piper chaba (Piperaceae) is a medicinal spice plant that possesses several pharmacological activities. In the present study, we for the first time studied the effect of P. chaba extract on breast cancer cells. P. chaba stem methanolic (PCSM) extract produced time and dose dependent cytotoxicity in luminal breast cancer cells (MCF-7 and T47D) with a minimal toxicity in breast normal cells (MCF-10A) at 10–100 µg/mL concentration. PCSM extract exerts 16.79 and 31.21 µg/mL IC50 for T47D and MCF-7 cells, respectively, in 48 h treatment. PCSM significantly arrests the T47D cells at the G0/G1 phase by reducing the CCND1 and CDK4 expression at mRNA and protein levels. PCSM extract treatment significantly altered nuclear morphology, mitochondria membrane potential, and production of reactive oxygen species in T47D cells at IC50 concentration. Extract treatment significantly altered the Bax/Bcl-2 ratio and altered caspase 8 and 3 mRNA/protein levels in T47D cells. Confocal microscopy showed an increase in late apoptosis in PCSM extract-treated breast cancer cells at IC50. Further, an increased caspase 9 and caspase 3/7 enzymatic activity was observed in test cells compared with nontreated cells. In conclusion, P. chaba phytocompound possesses the potential to induce cell cycle arrest and induce apoptosis in luminal breast cancer cells.

Industrial Fragrance Chemistry: A Brief Historical Perspective

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Perfumery has evolved from a handcraft activity, marking supreme aristocratic luxury in the Renaissance, to a global industry powering scent experiences for present-day consumers through the use of a myriad of consumer packaged goods. This contribution reviews major breakthroughs in the field, including landmark fragrance ingredients, technological advances in scent delivery, and key innovations in consumer products which created the demand for scientific and technological advancements in the scent domain. These innovations are presented chronologically, relying solely on information drawn from public written sources, spanning a time period of 150 years (1870-2020). We hope with this contribution to generate interest in the readership for this fascinating field, while celebrating 150 years of innovation for scented mass-market products..

Cucurbit[6]uril Hyperpolarized Chemical Exchange Saturation Transfer Pulse Sequence Parameter Optimization and Detectability Limit Assessment at 3.0T

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Molecular imaging is the future of personalized medicine; however, it requires effective contrast agents. Hyperpolarized chemical exchange saturation transfer (HyperCEST) can boost the signal of Hyperpolarized 129Xe MRI and render it a molecular imaging modality of high efficiency. Cucurbit[6]uril (CB6) has been successfully employed in vivo as a contrast agent for HyperCEST MRI, however its performance in a clinical MRI scanner has yet to be optimized. In this study, MRI pulse sequence parameter optimization was first performed in CB6 solutions in phosphate-buffered saline (PBS), and subsequently in whole sterile citrated bovine blood. The performance of four different depolarization pulse shapes (sinusoidal, 3-lobe sinc (3LS), rectangular (block), and hyperbolic secant (hypsec) was optimized. The detectability limits of CB6 in a clinical 3.0T MRI scanner was assessed using the optimized pulse sequences. The 3LS depolarization pulses performed best, and demonstrated 24% depletion in a 25µM solution of CB6 in PBS. It performed similarly in blood. The CB6 detectability limit was found to be 100µM in citrated bovine blood with a correspondent HyperCEST depletion of 30% ± 9%. For the first time, the HP 129Xe HyperCEST effect was observed in red blood cells (RBC) and had a similar strength as HyperCEST in plasma.