Novel 1,2,3-Triazole-Based Benzothiazole Derivatives: Efficient Synthesis, DFT, Molecular Docking, and ADMET Studies.

A new series of 1,2,3-triazole derivatives 5a-f based on benzothiazole were synthesized by the 1,3-dipolar cycloaddition reaction of S-propargyl mercaptobenzothiazole and α-halo ester/amide in moderate to good yields (47-75%). The structure of all products was characterized by 1H NMR, 13C NMR, and CHN elemental data. This protocol is easy and green and proceeds under mild and green reaction conditions with available starting materials. The structural and electronic analysis and 1H and 13C chemical shifts of the characterized structure of 5e were also calculated by applying the B3LYP/6-31 + G(d, p) level of density functional theory (DFT) method. In the final section, all the synthesized compounds were evaluated for their anti-inflammatory activity by biochemical COX-2 inhibition, antifungal inhibition with CYP51, anti-tuberculosis target protein ENR, DPRE1, pks13, and Thymidylate kinase by molecular docking studies. The ADMET analysis of the molecules 5a-f revealed that 5d and 5a are the most-promising drug-like molecules out of the six synthesized molecules.

In Vitro Targeting of NL2 Peptide Bounded on Poly L-DOPA Coated Graphene Quantum Dot.

Chemotherapy using drug delivery systems (DDS) can target cancer cells selectively and without affecting normal cells. In this paper, NL2 peptide as a tumor targeted peptide was bonded on the surface of poly 3,4-Dihydroxy-L-phenylalanine (Poly L-DOPA) graphene quantum dots (GQD), which was imprinted by Doxorubicin (DOX). The synthesized nanocomposite was characterized by Fourier-transform infrared spectroscopy (FTIR) and particle size was determined by dynamic light scattering (DLS) and Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). DOX release from synthesized nano-composite was investigated spectrophotometrically. Also, the toxicity and selectivity of NL2-GQD-NC on SK-BR-3 cell line were evaluated. FTIR and DLS experiment confirm the successful synthesis of Poly L-DOPA coated graphene quantum dots and their uniform particles. In vitro studies have shown that NL2-GQD-NC attached more to SK-BR-3 cells than NL2-free nanocomposites (GQD-NC). After attaching the cells could be imaged due to the presence of GQD particles and DOX release was accomplished in the tumor cells.

Hal-Py-SO3H as a novel and recyclable catalyst for highly efficient synthesis of xanthene and spiropyran derivatives.

The aim of this research is to synthesize a new sulfonic acid catalyst based on halloysite nanotubes (Hal-Py-SO3H) and characterize it as a solid acid nanocatalyst by various analytical techniques such as Fourier-Transformed Infrared spectroscopy (FTIR), Thermal gravimetric Analysis (TGA), X-ray Diffraction (XRD) analysis, Scanning Electron Microscopy (SEM), Vibrating Energy-Dispersive X-ray analysis (EDX), Transmission electron microscopy (TEM) and X-ray atomic mapping. Furthermore, this new catalyst was evaluated in synthesizing spiropyran derivatives via multicomponent reactions (MCRs) and Xanthen derivatives under environmentally sustainable conditions. The main advantages of this approach include green conditions, excellent yields, quick reaction rates, and ease of preparation. Additionally it was observed that the catalyst exhibited robust stability even after multiple recycling processes, indicating its potential for practical applications in sustainable chemical transformations.

Correction: DCID-mediated esterification of carboxylic acids with alcohols under mild conditions.

[This corrects the article DOI: 10.1039/D3RA04048H.].

QSAR models for the ozonation of diverse volatile organic compounds at different temperatures.

In order to assess the fate and persistence of volatile organic compounds (VOCs) in the atmosphere, it is necessary to determine their oxidation rate constants for their reaction with ozone (kO3). However, given that experimental values of kO3 are only available for a few hundred compounds and their determination is expensive and time-consuming, developing predictive models for kO3 is of great importance. Thus, this study aimed to develop reliable quantitative structure-activity relationship (QSAR) models for 302 values of 149 VOCs across a broad temperature range (178-409 K). The model was constructed based on the combination of a simplified molecular-input line-entry system (SMILES) and temperature as an experimental condition, namely quasi-SMILES. In this study, temperature was incorporated in the models as an independent feature. The hybrid optimal descriptor generated from the combination of quasi-SMILES and HFG (hydrogen-filled graph) was used to develop reliable, accurate, and predictive QSAR models employing the CORAL software. The balance between the correlation method and four different target functions (target function without considering IIC or CII, target function using each IIC or CII, and target function based on the combination of IIC and CII) was used to improve the predictability of the QSAR models. The performance of the developed models based on different target functions was compared. The correlation intensity index (CII) significantly enhanced the predictability of the model. The best model was selected based on the numerical value of Rm2 of the calibration set (split #1, Rtrain2 = 0.9834, Rcalibration2 = 0.9276, Rvalidation2 = 0.9136, and calibration = 0.8770). The promoters of increase/decrease for log kO3 were also computed based on the best model. The presence of a double bond (BOND10000000 and $10 000 000 000), absence of halogen (HALO00000000), and the nearest neighbor codes for carbon equal to 321 (NNC-C⋯321) are some significant promoters of endpoint increase.

De novo antioxidant peptide design via machine learning and DFT studies.

Antioxidant peptides (AOPs) are highly valued in food and pharmaceutical industries due to their significant role in human function. This study introduces a novel approach to identifying robust AOPs using a deep generative model based on sequence representation. Through filtration with a deep-learning classification model and subsequent clustering via the Butina cluster algorithm, twelve peptides (GP1-GP12) with potential antioxidant capacity were predicted. Density functional theory (DFT) calculations guided the selection of six peptides for synthesis and biological experiments. Molecular orbital representations revealed that the HOMO for these peptides is primarily localized on the indole segment, underscoring its pivotal role in antioxidant activity. All six synthesized peptides exhibited antioxidant activity in the DPPH assay, while the hydroxyl radical test showed suboptimal results. A hemolysis assay confirmed the non-hemolytic nature of the generated peptides. Additionally, an in silico investigation explored the potential inhibitory interaction between the peptides and the Keap1 protein. Analysis revealed that ligands GP3, GP4, and GP12 induced significant structural changes in proteins, affecting their stability and flexibility. These findings highlight the capability of machine learning approaches in generating novel antioxidant peptides.

DCID-mediated esterification of carboxylic acids with alcohols under mild conditions.

DCID (Dichloroimidazolidinedione) 2 is used as a novel coupling reagent for the esterification of carboxylic acids with alcohols at room temperature. The reaction represents the first DCID-promoted esterification under mild conditions with good to excellent yields. Reactions can proceed smoothly with those bearing electron-withdrawing and donating group(s) on the carboxylic acids and benzyl alcohols at ambient temperature. Furthermore, we proposed a plausible mechanism and confirmed it by isolating and characterizing intermediates 3a and 7. The structures of the synthesized compounds were confirmed by comparison of melting points and NMR spectra.

Magnet-responsive choline carbomer ionogels as a versatile and recyclable catalyst for one-pot synthesis of benzopyran in water.

Ionogels are gaining popularity as a potential replacement for volatile organic solvents in various processes, such as catalysts, electrochemistry, spectroscopy, and medicinal chemistry, due to their low toxicity, high thermal stability, and good solubility. Magnet-responsive ion gels with high magnetic susceptibility are promising and can be used as catalysts, sensors, and MRI contrast agents. Herein, we fabricated simple and novel magnet choline carbomer ionogels using a precipitation-deposition method with carbomers and choline hydroxide. The morphology and structure of the resulting ionogels were analyzed using various characterization techniques, including FTIR, EDX, TGA, and SEM spectroscopy. These magnet ionogels were effective catalysts for a one-pot, three-component synthesis of benzopyran derivatives, providing mild reaction conditions, environmental friendliness, and good to excellent (78-96%) yields within a short reaction time (1-2 h). Additionally, the magnet ionogels were easily recyclable, and they could be reused up to five times without catalytic deactivation.

Design and optimization various formulations of PEGylated niosomal nanoparticles loaded with phytochemical agents: potential anti-cancer effects against human lung cancer cells.

BACKGROUND: Phytochemicals and their derivatives are good options to improve treatment efficiency in cancer patients. Artemisinin (ART) and metformin (MET) are widely used phytochemicals to treat various types of cancers. However, their application because of their dose-dependent side effects, and poor bioavailability brings several challenges. Niosome is a novel nanocarrier that is the best choice to encapsulate both lipophilic and hydrophilic drugs. In this study, we synthesized and characterized various formulations of PEGylated (polyethylene glycol) niosomal nanoparticles co-loaded with ART-MET and evaluated their anticancer effect on A549 lung cancer cells. METHODS: Various formulations of PEGylated noisome were prepared by the thin-film hydration method and characterized in size, morphology, release pattern, and physicochemical structure. The cytotoxic effect of the free ART-MET and optimized PEGylated niosomal nanoparticles loaded with ART-MET on A549 cells were evaluated by MTT assay. Furthermore, the Real-time PCR (RT-PCR) technique used to evaluate apoptotic and anti-apoptotic gene expression. RESULTS: The size, encapsulation efficiency (EE), and polydispersity index (PDI) of the optimized nanoparticles are 256 nm, 95%, and 0.202, respectively. Additionally, due to the PEGylation hydrophilic character, there is a major consideration of the high impact of PEGylation on reducing niosome size. According to the results of the MTT assay, free ART-MET and ART-MET-loaded niosomal nanoparticles showed dose-dependent toxicity and inhibits the growth of A549 lung cancer cells. Furthermore, the RT-PCR results indicated that ART-MET-loaded niosomal nanoparticles have a higher anti-proliferative effect by inhibiting anti-apoptotic and inducing apoptotic gene expression in A549 lung cancer cells. CONCLUSIONS: Our study revealed that the simultaneous use of ART and MET in the optimized PEGylated niosomal nanoparticles delivery system could be an appropriate approach to improve the effectiveness of lung cancer treatment.

Synthesis and characterization of epoxide impurities of abiraterone acetate.

Abiraterone acetate is an antiandrogen steroidal drug that is used to treat patients with metastatic prostate cancer. During the process development of abiraterone acetate, two process α and ß-epoxy abiraterone acetate related impurities (2 and 3) were observed along with the final API. In the present work we describe the synthesis of these two known impurities using abiraterone acetate in the presence of hydrogen peroxide and acetic acid as oxidizing agent. The structure of these impurities fully characterized by NMR, Mass, CHN and HPLC analysis.

An Efficient Synthesis of Pyrano[c]chromenediones and [1,3]Dioxolo[g] chromeneones Catalyzed by Nickel(II) Chromite Nanoparticles Through a Three-Component Domino Reaction.

BACKGROUND: Due to the importance of fused chromene motifs in bioactive compounds, the current research aimed to explore novel methods for the construction of heterocyclic scaffolds. Regarding the attractive features of developing novel methodological approaches in the presence of heterogeneous nanocatalysts, we will try to synthesize 4-aryl-3,4-dihydro-2H,5H-pyrano[3,2- c]chromene-2,5-diones and 8-aryl-7,8-dihydro-6H-[1,3]dioxolo[4,5-g]chromene-6-ones. OBJECTIVE: The aim of the present research was to prove the catalytic efficiency of the synthesized nickel(II) chromite nanoparticles (NiCr2O4 NPs) as bifunctional Lewis acid-Lewis base catalyst in the synthesis of pyrano[c]chromenediones and [1,3]dioxolo[g]chromeneones. METHODS: Pyrano[c]chromenediones and [1,3]dioxolo[g]chromeneones were conveniently prepared from a three-component condensation reaction between aromatic aldehydes, Meldrum's acid, and active methylene compounds including 4-hydroxycoumarin or 3,4-methylenedioxyphenol using NiCr2O4 NPs as an efficient, readily available, and recyclable catalyst, under ethanol-drop grinding at room temperature. The synthesized compounds were characterized by IR, 1H, and 13C NMR spectroscopy and also by elemental analyses. RESULTS: A number of 4-aryl-3,4-dihydro-2H,5H-pyrano[3,2-c]chromene-2,5-diones and 8-aryl- 7,8-dihydro-6H-[1,3]dioxolo[4,5-g]chromene-6-ones were effectively synthesized as target compounds in high yields. CONCLUSION: This study provides a simple, inexpensive, and NiCr2O4 NPs catalyzed route to synthesis pyrano[c]chromenediones and [1,3]dioxolo[g]chromeneones in high yields. The reaction offers several benefits, including simple experimental procedures, higher yields, shorter reaction times, and the use of easily obtained and recyclable catalyst compared with previously reported methods and has a great scope for development.

Nickel(II) Chromite Nanoparticles: An Eco-Friendly and Reusable Catalyst for Synthesis of 2,4-Diamino-6-aryl-pyrimidine-5-yl Cyanides under Ultrasonic Radiation.

BACKGROUND: One of the principal factors in the field of research in green chemistry is to drive chemical reactions using ultrasonication as a versatile synthetic tool. Moreover, nanostructured metal salts occupy an important position as low cost, efficient, heterogeneous, and green catalysts in chemical reactions. Pyrimidine has also acquired significance because it is a core structure in a variety of natural and non-natural agents, many of which display versatile biological activities and medical applications. OBJECTIVE: The aim of this study was to explore the role of nickel(II) chromite nanoparticles (NiCr2O4 NPs) as a green and recyclable catalyst for the synthesis of 2,4-diamino-6-arylpyrimidine- 5-yl cyanides under ultrasonic radiation. METHODS: A direct cyclocondensation reaction of guanidine nitrate, aromatic aldehydes, and malononitrile was performed using NiCr2O4 NPs as an effective heterogeneous catalyst under ultrasonic radiation at room temperature conditions to prepare 2,4-diamino-6-aryl-pyrimidine-5-yl cyanides in high yields. The described catalyst was prepared successfully according to a simple hydrothermal route and fully characterized by the X-Ray diffraction (XRD) technique, dispersive energy X-Ray (EDS) analysis, scanning electron microscopy (SEM), and dynamic light scattering (DLS). RESULTS: A number of 2,4-diamino-6-aryl-pyrimidine-5-yl cyanides were effectively synthesized in high yields (94-98%) within short reaction times (15 min). All synthesized compounds were well characterized by IR, 1H and 13C NMR spectroscopy, and also by elemental analyses. CONCLUSION: In conclusion, a simple, efficient, and green synthesis of 2,4-diamino-6-arylpyrimidine- 5-yl cyanides was developed using NiCr2O4 NPs as a green nanocatalyst, and under ultrasound radiation as a green tool. The mild reaction conditions, avoiding the use of toxic solvents or reagents, high atom economy, high yields, and simple workup are the attractive features of this new protocol.

Anion recognition by urea metal-organic frameworks: remarkable sensitivity for arsenate and fluoride ions.

Functionalized metal-organic frameworks (F-MOFs) are known as a promising chemical sensors since they have specific merits like fixed functionalized ligands projecting into the pores which can be utilized to enhance sensitivity and selectivity. Due to the important role of anions in biological process and environmental systems, there is an increasing interest in synthesis and design of new receptors for anions. Urea groups can operate as a hydrogen bond donating site with hydrogen bond acceptor molecules. Strong and directional hydrogen-bonding between the positive urea groups and anions could reduce vibrational quenching and enhance the fluorescence intensity. In this study, two luminescent porous urea decorated MOFs have been successfully assembled and structurally characterized. Luminescence studies of these MOFs toward anions revealed that these F-MOFs exhibit high sensitivity and selectivity toward H2AsO4- and F- anions as two major ground water pollutants. Moreover, the proposed materials have been applied for the removal of arsenate and nitrate in contaminant well water samples. Graphical abstract.

One-pot synthesis of amides via the oxidative amidation of aldehydes and amines catalyzed by a copper-MOF.

An efficient method for the oxidative amidation of aldehydes with primary aromatic and aliphatic amines has been developed for the synthesis of a wide variety of amides using inexpensive Cu2(BDC)2DABCO (Cu-metal-organic framework [MOF]) as a recyclable heterogeneous catalyst, and N-chlorosuccinimide and aqueous tert-butyl hydroperoxide as oxidants in acetonitrile. This amidation reaction is operationally straightforward and provides secondary amides in good yields in most cases, utilizing inexpensive and readily available reagents under mild conditions.

Preparation and characterization of polycaprolactone nanocapsules containing pretilachlor as a herbicide nanocarrier.

Polycaprolactone nanocapsules (PCL) containing pretilachlor were prepared, and Fourier transform infrared spectroscopy, atomic force microscopy, and transmission electron microscopy were used for their structural and morphological investigations. The results revealed that the nanocapsules had irregular shape and their particles size was in the range of 70-200 nm. The encapsulation efficiency of pretilachlor was measured as 99.5 ± 1.3% using high-performance liquid chromatography analysis. The physicochemical stability studies over 60 days showed that the nanocapsules were stable in the suspension without any aggregation. The herbicide activity was examined in a pre-emergence manner using barnyard grass as a target plant and rice as a non-target plant. The nanoformulation had no negative effect on rice plant. However, its effect on barnyard grass was significant. The cytotoxicity analysis indicated that the nanocapsulated herbicide is less toxic rather than the commercial formulation. Therefore, encapsulation of pretilachlor in PCL nanocapsules can be used effectively to construct environmentally friendly PCL-herbicide systems in agriculture.

Immobilized copper nanoparticles on nitrogen-rich porous activated carbon from egg white biomass: a robust hydrophilic-hydrophobic balance catalyst for click reaction.

Biomass conversion to carbonaceous materials and their use in various applications, such as capacitors, catalyst supports, and adsorbents, have attracted considerable attention from the viewpoint of green chemistry. In this regard, chicken egg white is one of the most important biomass, which can act as an in situ nitrogen doping source. In this paper, nitrogen-rich porous carbon material was synthesized from egg white biomass via pyrolysis at 600 °C under nitrogen atmosphere, followed by chemical activation with KOH at 500 °C. The results showed that the as-synthesized porous carbon material has a high content of nitrogen and high surface area, on which nitrogen can tune the surface hydrophobicity-hydrophilicity through interaction with water molecules. Then, the copper nanoparticles were immobilized on the surface of nitrogen-rich activated carbon by a chemical reduction method. Nanocatalyst structure was characterized by elemental analysis, TEM, AFM, Raman, FT-IR, porosimetry and atomic adsorption techniques. Finally, catalytic activity was evaluated for the one-pot synthesis of triazole in aqueous medium. The nanocatalyst offers some advantages such as excellent activity, low loading of catalyst, good yields of products and short reaction times.