Tunable supramolecular self-assemblies based on cyclodextrin polymer as a loading platform for water-soluble drugs

Drug loading capacity is a crucial character of nano-scaled drug carriers to achieve high quality pharmaceutical preparations. However, efficient encapsulation of water-soluble small molecular drugs still faces large obstacles in many cases. Herein, we designed a novel supramolecular delivery system constructed by poly(β-cyclodextrin) containing benzoic acid groups (PCD-PA) and adamantyl terminated poly(ethylene glycol) (PEG-AD) to provide multiple intermolecular interactions for competent loading of water-soluble small-molecular drugs. PCD-PA had multiple host molecules, and PEG-AD could be inserted via host-guest interaction in different proportion to adjust the composition of supramolecular carrier. Meanwhile, π-π stacking and electrostatic interaction furnished by benzoic acid groups served as binding force for drug entrapment, which led to considerable loading capacity for several water-soluble drugs. Among the drugs with different chemical structures, mitoxantrone hydrochloride and doxorubicin hydrochloride bearing anthraquinone rings and several protonable amino groups acquired the highest loading content as about 14 % in PCD-PA3/PEG-AD supramolecular self-assemblies. Further computational simulations investigated the mechanism of drug loading based on the interactions between the carrier materials and the payloads. In addition, the weakly acidic environment obviously accelerated the release of certain drugs. All in all, this self-assembled supramolecular nano-system displayed great potentials as a delivery platform for diverse water-soluble drugs.

Chloride-mediated enhancement in Cu(II)-catalyzed Fenton-like reaction: The overlooked reactive chlorine species

The practical application of Cu(II)-catalyzed Fenton-like reaction (Cu(II)/H2O2) exhibits a low efficiency in the degradation of refractory compounds of wastewater. The impact of chloride ions (Cl-) on Fenton-like reactions have been investigated, but the influence mechanism is still unclear. Herein, the presence of Cl- (5 mM) significantly accelerated the degradation of benzoic acid (BA) under neutral conditions. The degradation of BA follows pseudo-first-order kinetics, with a degradation rate 7.3 times higher than the Cu(II)/H2O2 system. Multiple evidences strongly demonstrated that this reaction enables the production of reactive chlorine species (RCS) rather than HO• and high-valent copper (Cu(III)). The kinetic model revealed that Cl- could shift reactive species from the key intermediate (Cu(III)-chloro complexes) to RCS. Dichlorine radicals (Cl2•-) was discovered to play a crucial role in BA degradation, which was largely overlooked in previous reports. Although the reaction rate of Cl2•- with BA (k = 2.0 × 106 M-1 s-1) is lower than that of other species, its concentration is 10 orders of magnitude higher than that of Cu(III) and HO•. Furthermore, the exceptional efficacy of the Cu(II)/H2O2 system in BA degradation was observed in saline aquatic environments. This work sheds light on the previously unrecognized role of the metal-chloro complexes in production the RCS and water purification.

Surface-Enhanced, Low-Frequency Raman Spectroscopy: A Sensitive Screening Tool for Structural Characterization of Pharmaceuticals

Surface-enhanced, low-frequency Raman spectroscopy (SELFRS) was explored for its potential as a structural screening tool within pharmaceutical applications, including facile small-scale multicomponent analysis. Paracetamol was used as the model drug, and its crystallization behavior with or without the presence of a templating agent (benzoic acid) was investigated using commercial silver-based SERS substrates. The Raman imaging was carried out using two different LFR-enabled instruments employing 532 and 785 nm incident lasers, where each of the setups showed certain affinity for differentiating lattice vibrations of the polymorphic forms of interest: form I and form II. A comparison of SELFRS, SERS, and their combination using chemometrics showed the potential for the LFR spectral range to improve surface-enhanced measurements either individually or in combination with the typically-used fingerprint region without the need to alter the experimental configuration. Additionally, the use of crystallization additives that helped to drive the formation of metastable form II was shown using SELFRS to provide additional mechanistic understanding of the template-assisted crystallization processes.

The Nicotiana tabacum UGT89A2 enzyme catalyzes the glycosylation of di- and trihydroxylated benzoic acid derivatives

Glycosyltransferases catalyze the transfer of a glycoside group to a wide range of acceptor compounds to produce glycoconjugates with diverse biological and pharmacological activities. The present work reports the identification and biochemical characterization of Nicotiana tabacum UGT89A2 glycosyltransferase (NtUGT89A2). The enzyme is a monomer in solution that catalyzes the O-β-glucosylation of di- and tri-hydroxylated and chlorinated derivatives of benzoic acid. NtUGT89A2 has a preference for 2,5-dihydroxybenzoic acid (2,5-DHBA) over 2,3-dihydroxybenzoic acid (2,3-DHBA) and 2,4-dihydroxybenzoic acid (2,4-DHBA). Other substrates that can be used by NtUGT89A2 include 3,4,5-trihydroxybenzoic acid and chlorinated derivatives such as 2-chloro-5-hydroxybenzoic acid (2-Cl-5-HBA). The substrates of NtUGT89A2 were identified by thermal stability experiments, where we observed a maximum increase of the thermal denaturation midpoint (Tm) of 10 °C in the presence of 2,5-DHBA and UDP-glucose. On the other hand, the highest specific activity was obtained with 2,5-DHBA (225 ± 1.7 nkat/mg). Further characterization revealed that the enzyme has a micromolar affinity for its substrates. Notably, the enzyme retains full activity after incubation at 70 °C for 1 h. These results provide a basis for future functional and structural studies of NtUGT89A2.

On the discrepancy between crossovers of solubility in supercritical carbon dioxide and retention in supercritical fluid chromatography

Various crossover phenomena are immanent to supercritical fluids due to multidirectional temperature effects in highly compressible supercritical fluid media. Solubility crossover, i.e. controversial effect of temperature on solubility at different pressures, is probably the most well-known among them. A curious discrepancy in upper crossover pressure values between solubility in supercritical carbon dioxide and retention in supercritical fluid chromatography with pure CO2 as an eluent was unexpectedly observed for several non-polar compounds on different stationary phases. In some cases, retention crossover was found to happen at pressures almost twice as high as pressures for solubility crossover for the same compound. Retention data for three solutes with known solubility crossovers: anthracene, benzoic acid and vanillin, were collected at different pressures and temperatures for several stationary phases. The existence of upper retention crossovers, i.e. such pressure values beyond which temperature increase starts decreasing retention, were registered for all solute-sorbent combinations. Using known thermodynamic models of temperature effect on retention in supercritical fluid chromatography and on solubility in supercritical carbon dioxide, possible reasoning for the observed discrepancies is discussed. Major contribution of the balance between adsorption and partition retention mechanisms in defining retention crossover values is hypothesized.

A comparative study of passive drug diffusion through human skin via intercellular and sweat duct route: effect of aging

A method of drug delivery that could provide control over medicine reaching the bloodstream for systemic circulation would be of immense importance. This work presents a comparative study of the temporal and spatial variation of drugs diffusing passively through two separate routes of human skin, namely intercellular (ICR) and sweat duct route (SDR). An analysis is carried out for two age groups (young < 40 years and old > 60 years of age). Governing equations based on Fick's law for mass transfer have been solved numerically using an in-house developed code. The code has been validated thoroughly with numerical and experimental work from the literature. Each skin route is modeled into three compartments sandwiched between the donor and receiver compartments. To understand the role of diffusion and partition coefficient on drug permeation, four drugs, namely hydrocortisone, trans-cinnamic acid, caffeine, and benzoic acid, are considered. The drug diffusion rate is found greater through ICR as compared to SDR. Further, the amount of drugs diffusing through both routes increases with age. Desirable drug characteristic is inferred to be a lower value of partition coefficient and a higher value of diffusion coefficient. This study could lead to real-time assessment of drugs reaching the bloodstream and beyond.

Effects of benzoic acid synthesized from Cinnamomum cassia by green chemistry on valproic acid-induced neurotoxicity in zebrafish embryos

Benzoic acid, the most basic aromatic carboxylic acid, is produced industrially and used in cosmetic, hygiene, and pharmaceutical items as a flavoring ingredient and/or preservative. The significance of sodium benzoate, a metabolite of cinnamon, used as a food preservative and FDA-approved medication to treat urea cycle abnormalities in humans, has been shown to raise the levels of neurotrophic factors. Valproic acid (VPA), a commonly used anti-epileptic and mood-stabilizing medication, causes behavioral and intellectual problems and is a commonly used agent to induce animal model for autism. Aim of this study is to determine the effects of benzoic acid synthesized from Cinnamomum Cassia by green chemistry method on gene expressions related to autism development in case of VPA toxicity. Zebrafish embryos were exposed to low and high doses of benzoic acid for 72 h post-fertilization. Locomotor activities were determined. Acetylcholinesterase (AchE), lipid peroxidation, nitric oxide (NO), sialic acid (SA), glutathione (GSH)-S-transferase, catalase (CAT), and superoxide dismutase (SOD) activities were determined spectrophotometrically. eif4b, adsl, and shank3a expressions were determined by RT-PCR as autism-related genes. Although high-dose benzoic acid inhibited locomotor activity, benzoic acid at both doses ameliorated VPA-induced disruption in oxidant-antioxidant balance and inflammation in zebrafish embryos and was effective in improving the impaired expression of autism-related genes.

Comparative analysis of Escherichia coli Nissle 1917 ghosts quality: a study of two chemical methods

The gram-negative bacterium Escherichia coli Nissle 1917 (EcN) has long been recognized for its therapeutic potential in treating various intestinal diseases. Bacterial ghosts (BGs) are empty shells of non-living bacterial cells that demonstrate enormous potential for medicinal applications. Genetic and chemical techniques can create these BGs. In the current study, we produced Escherichia coli Nissle 1917 ghosts (EcNGs) for the first time using benzoic acid (BA) and sodium hydroxide (SH). BA is a feeble acidic chemical that enhances gram-negative bacteria's external membrane permeability, reduces energy production, and decreases internal pH. SH has shown success in producing BGs from some gram-negative and gram-positive organisms. This research aims to produce EcNGs using the minimum inhibitory concentration (MIC) of SH and BA, specifically 3.125 mg/mL. We assessed the bacterial quality of the BGs produced using quantitative PCR (qPCR) and Bradford protein assays. Field emission scanning electron microscopy (FE-SEM) showed the three-dimensional structure of EcNGs. The study confirmed the presence of tunnel-like pores on the outer surface, indicating the preservation of cell membrane integrity. Importantly, this investigation introduces BA as a novel chemical inducer of EcNGs, suggesting its potential alongside SH for efficient EcNG formation.

Increased energy efficiency using pulse-potential electrochemical advanced oxidation processes

The research investigated the pulse potential effect on Electrochemical Advanced Oxidation Processes (EAOPs) for benzoic acid oxidation. The current efficiency of the electrooxidation is enhanced by changing the pulse frequency and potential on electrodes. The experiments showed that there are opposing phenomena affecting energy efficiency. On the one hand, pulse potential accelerates the mass transfer of benzoic acid in an electric field. On the other hand, pulse potential increases the non-faradic current that uses energy without causing oxidation. Using the Sand equation and the electric double-layer theory, we optimized the pulse frequency and voltage amplitude to achieve the highest energy efficiency for the pulse potential EAOPs. Compared with DC (Direct current) EAOPs, the pulse potential EAOPs save 50% EE/O and have a 41 % CE for the 4_2 V cycle at 50 Hz. Therefore, pulse potential EAOPs can achieve both high pollutant degradation efficiency and low energy consumption at the same time.

Trivalent Copper Ion-Mediated Dual Oxidation in the Copper-Catalyzed Fenton-Like System in the Presence of Histidine

The Cu(II)/H2O2 system is recognized for its potential to degrade recalcitrant organic contaminants and inactivate microorganisms in wastewater. We investigated its unique dual oxidation strategy involving the selective oxidation of copper-complexing ligands and enhanced oxidation of nonchelated organic compounds. L-Histidine (His) and benzoic acid (BA) served as model compounds for basic biomolecular ligands and recalcitrant organic contaminants, respectively. In the presence of both His and BA, the Cu(II)/H2O2 system rapidly degraded His complexed with copper ions within 30 s; however, BA degraded gradually with a 2.3-fold efficiency compared with that in the absence of His. The primary oxidant responsible was the trivalent copper ion [Cu(III)], not hydroxyl radical (•OH), as evidenced by •OH scavenging, hydroxylated BA isomer comparison with UV/H2O2 (a •OH generating system), electron paramagnetic resonance, and colorimetric Cu(III) detection via periodate complexation. Cu(III) selectively oxidized His owing to its strong chelation with copper ions, even in the presence of excess tert-butyl alcohol. This selectivity extended to other copper-complexing ligands, including L-asparagine and L-aspartic acid. The presence of His facilitated H2O2-mediated Cu(II) reduction and increased Cu(III) production, thereby enhancing the degradation of BA and pharmaceuticals. Thus, the Cu(II)/H2O2 system is a promising option for dual-target oxidation in diverse applications.

Quantification of Free Radicals from Vaping Electronic Cigarettes Containing Nicotine Salt Solutions with Different Organic Acid Types and Concentrations

Electronic (e-) cigarette formulations containing nicotine salts from a range of organic acid conjugates and pH values have dominated the commercial market. The acids in the nicotine salt formulations may alter the redox environment in e-cigarettes, impacting free radical formation in e-cigarette aerosol. Here, the generation of aerosol mass and free radicals from a fourth-generation e-cigarette device was evaluated at 2 wt % nicotine salts (pH 7, 30:70 mixture propylene glycol to vegetable glycerin) across eight organic acids used in e-liquids: benzoic acid (BA), salicylic acid (SLA), lactic acid (LA), levulinic acid (LVA), succinic acid (SA), malic acid (MA), tartaric acid (TA), and citric acid (CA). Furthermore, 2 wt % BA nicotine salts were studied at the following nicotine to acid ratios: 1:2 (pH 4), 1:1 (pH 7), and 2:1 (pH 8), in comparison with freebase nicotine (pH 10). Radical yields were quantified by spin-trapping and electron paramagnetic resonance (EPR) spectroscopy. The EPR spectra of free radicals in the nicotine salt aerosol matched those generated from the Fenton reaction, which are primarily hydroxyl (OH) radicals and other reactive oxygen species (ROS). Although the aerosol mass formation was not significantly different for most of the tested nicotine salts and acid concentrations, notable ROS yields were observed only from BA, CA, and TA under the study conditions. The e-liquids with SLA, LA, LVA, SA, and MA produced less ROS than the 2 wt % freebase nicotine e-liquid, suggesting that organic acids may play dual roles in the production and scavenging of ROS. For BA nicotine salts, it was found that the ROS yield increased with a higher acid concentration (or a lower nicotine to acid ratio). The observation that BA nicotine salts produce the highest ROS yield in aerosol generated from a fourth-generation vape device, which increases with acid concentration, has important implications for ROS-mediated health outcomes that may be relevant to consumers, manufacturers, and regulatory agencies.

Preparation and sustained-release of chitosan-alginate bilayer microcapsules containing aromatic compounds with different functional groups

This study investigated the release of aromatic compounds with distinct functional groups within bilayer microcapsules. Bilayer microcapsules of four distinctive core materials (benzyl alcohol, eugenol, cinnamaldehyde, and benzoic acid) were synthesized via freeze-drying. Chitosan (CS) and sodium alginate (ALG) were used as wall materials. CS concentration, using orthogonal experiments with the loading ratio as a metric. Under optimal conditions, three other types of microcapsules (cinnamic aldehyde, benzoic acid, and benzyl alcohol) were obtained. The four types of microcapsules were characterized using Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscope (TEM), and thermogravimetric analysis (TGA), and their sustained release characteristics were evaluated. The optimal conditions were: CS dosage, 1.2 %; CS-to-eugenol mass ratio, 1:2; and CS-to-ALG mass ratio, 1:1. By comparing the IR spectra of the four types of microcapsules, wall material, and core material, the core materials were revealed to be encapsulated within the wall material. SEM results revealed that the granular protuberances on the surface of the microcapsules were closely aligned and persistent when magnified 2000×. The TEM results indicated that all four microcapsules had a spherical and bilayer structure. The thermal stability and sustained release results showed that the four microcapsules were more resilient and less volatile than the four core materials. The release conformed to first-order kinetics, and the release ratios of the four microcapsules were as follows: benzyl alcohol microcapsules ˃ eugenol microcapsules ˃ cinnamaldehyde microcapsules ˃ benzoic acid microcapsules. The prepared bilayer microcapsules encapsulated four different core materials with good sustained release properties.

Adsorption simulation of 2,4-D pesticide on novel zinc-based 2-amino-4-(1H-1,2,4-triazole-4-yl)benzoic acid coordination complexes using machine learning approach

The capacity of zinc-based 2-amino-4-(1H-1,2,4-triazole-4-yl)benzoic acid coordination complex (Zn(NH2-TBA)2) and modified Zn(NH-TBA)2COMe complex for removal of 2,4-dichlorophenoxyacetic acid (2,4-D) from aqueous solutions was investigated through adsorption modeling and artificial intelligence tools. Analyzing the adsorption characteristics of pesticides helps in studying the groundwater pollution by pesticides in agriculture area.In this study, Zn(NH2-TBA)2 was synthesized using Schiff base and its surface was modified using acetic anhydride group and their physical characteristics were identified using proton NMR, FTIR, and XRD. NMR results showed maximum modification yield obtained was 65% after 5 days. The porous structure and surface area monitored using nitrogen isotherm and BET surface area analysis presented relatively less surface area and porosity after modification. Adsorption modelling indicated that Toth model with a maximum adsorption capacity of 150.8 mg/g and 100.7 mg/g represents the homogenous adsorption systems which satisfy both low- and high-end boundary of adsorbate concentration in all settings according to the optimum point, while the kinetics and rate of 2,4-D adsorption follow the pseudo-first-order kinetic model in all situations. Artificial neural network (ANN), support vector regression, and particle swarm optimized least squares-support vector regression (PSO-LSSVR) were used for the optimization and modelling of adsorbent mass, adsorbate concentration, contact time, and temperature to develop predictive equations for the simulation of the adsorption efficiency of 2,4-D pesticide. The obtained results exhibited the better performance of ANN and PSO-LSSVR for prediction of adsorption results. The mean square error values of ANN (0.001, 0.012) and PSO-LSSVR (0.121, 0.105) were obtained for Zn(NH2-TBA)2 and Zn(NH-TBA)2COMe, respectively, while their respective coefficient of determination (R2) obtained were 0.999 and 0.988 for ANN and 0.980 and 0.825 for PSO-LSSVR. The study specified that machine learning predictive behavior performed better for Zn(NH2-TBA)2 compared to Zn(NH-TBA)2COMe that is also supported by theoretical kinetics and isotherm models. The research concludes that artificial intelligence models are the most efficient tools for studying the predictive behavior of adsorption data.

Sorption behavior of three aromatic acids (benzoic acid, 1-naphthoic acid and 9-anthroic acid) on biochar: Cosolvent effect in different liquid phases

Influence of the cosolvent on the sorption of organic acids on biochar has not been well understood. For this purpose, the sorption (log Km, L kg-1) of three aromatic acids (benzoic acid (BA, pKa = 4.20), 1-naphthoic acid (1-NAPA, pKa = 3.70), and 9-anthroic acid (9-ANTA, pKa = 3.65) was evaluated as a function of methanol volume fraction (fc = 0.0, 0.25, and 0.5), liquid pH (2.5 and 7.0), ionic composition (CaCl2 and KCl) and ionic strength (0.005 M, 0.5 M, and 1 M CaCl2). A giant Miscanthus-derived biochar (ZPC of 2.86) was used as the sorbent. For all solutes, the sorption coefficients (log Km) measured at pH 2.5 (i.e., pH < pKa) tended to decrease with increasing fc, as expected from the cosolvency model, while the result obtained at pH 7.0 was not fully explained by the same model. The log Km of 1-NAPA in the CaCl2 system was always greater than in the KCl system (p < 0.05) and the impact became pronounced at high pH (>pKa) with increasing fc. Increasing the Ca2+ concentration at fc = 0.0 (from 0.005 M to 1 M) enhanced the value by 0.32 log unit of Km. These phenomena indicate a significant role of dissolved Ca2+ in the liquid phase, most likely due to the formation of cation bridges between aromatic carboxylates and the biochar surface (i.e., [R-COO--Ca2+]-{Biochar-}). A decrease in the dielectric constant of the methanol mixture could fortify the formation of this bridge. Regardless of the degree of cosolvency power (σ), as the number of aromatic rings of solutes increases, Km decreases in the order BA > 1-NAPA > 9-ANTA, where fc = 0.0. In conclusion, the sorption potential of biochar can be significantly weakened by increasing pH and fc, and in the absence of a divalent cation.

The Discovery of GSK3640254, a Next-Generation Inhibitor of HIV-1 Maturation

GSK3640254 is an HIV-1 maturation inhibitor (MI) that exhibits significantly improved antiviral activity toward a range of clinically relevant polymorphic variants with reduced sensitivity toward the second-generation MI GSK3532795 (BMS-955176). The key structural difference between GSK3640254 and its predecessor is the replacement of the para-substituted benzoic acid moiety attached at the C-3 position of the triterpenoid core with a cyclohex-3-ene-1-carboxylic acid substituted with a CH2F moiety at the carbon atom α- to the pharmacophoric carboxylic acid. This structural element provided a new vector with which to explore structure-activity relationships (SARs) and led to compounds with improved polymorphic coverage while preserving pharmacokinetic (PK) properties. The approach to the design of GSK3640254, the development of a synthetic route and its preclinical profile are discussed. GSK3640254 is currently in phase IIb clinical trials after demonstrating a dose-related reduction in HIV-1 viral load over 7-10 days of dosing to HIV-1-infected subjects.

Novel diosgenin-amino acid-benzoic acid mustard trihybrids exert antitumor effects via cell cycle arrest and apoptosis

In discovering new powerful antitumor agents, two series of novel diosgenin-amino acid-benzoic acid mustard trihybrids (7a-7 g and 12a-12 g) were designed and synthesized. The antiproliferative activities were tested against five human tumor cell lines and one normal cell line using CCK-8 assays. Among the trihybrids, 12e was the most promising compound, which inhibited T24 cells with IC₅₀ value of 6.96 μM, and was stronger than its parent compound diosgenin (IC₅₀ = 32.33 μM). In addition, 12e had weak cytotoxicity on the normal GES-1 cell line (IC₅₀ = 213.74 μM). Moreover, 12e could cause G2/M cell cycle arrest, increase the percentage of apoptosis, induce mitochondrial depolarization, and promote reactive oxygen species generation in T24 cells. Further studies on antitumor mechanism demonstrated that 12e triggered the intrinsic (mitochondrial) and extrinsic (death receptor) apoptotic pathways. More importantly, 12e could inhibit T24 cell proliferation in an in vivo zebrafish xenograft model. Therefore, 12e, as a novel trihybrid with potent cytotoxicity, might be applied as a promising skeleton for antitumor agents, which deserved further optimization.

Synthesis, In Silico and In Vitro Evaluation of Antimicrobial and Toxicity Features of New 4-[(4-Chlorophenyl)sulfonyl]benzoic Acid Derivatives

The multi-step synthesis, physico-chemical characterization, and biological activity of novel valine-derived compounds, i.e., N-acyl-α-amino acids, 1,3-oxazol-5(4H)-ones, N-acyl-α-amino ketones, and 1,3-oxazoles derivatives, bearing a 4-[(4-chlorophenyl)sulfonyl]phenyl moiety are reported here. The structures of the newly synthesized compounds were confirmed by spectral (UV-Vis, FT-IR, MS, ¹H- and ¹³C-NMR) data and elemental analysis results, and their purity was determined by RP-HPLC. The new compounds were assessed for their antimicrobial activity and toxicity to aquatic crustacean Daphnia magna. Also, in silico studies regarding their potential mechanism of action and toxicity were performed. The antimicrobial evaluation revealed that the 2-{4-[(4-chlorophenyl)sulfonyl]benzamido}-3-methylbutanoic acid and the corresponding 1,3-oxazol-5(4H)-one exhibited antimicrobial activity against Gram-positive bacterial strains and the new 1,3-oxazole containing a phenyl group at 5-position against the C. albicans strain.

Nonpeptidic, Polo-Box Domain-Targeted Inhibitors of PLK1 Block Kinase Activity, Induce Its Degradation and Target-Resistant Cells

PLK1, polo-like kinase 1, is a central player regulating mitosis. Inhibition of the subcellular localization and kinase activity of PLK1 through the PBD, polo-box domain, is a viable alternative to ATP-competitive inhibitors, for which the development of resistance and inhibition of related PLK family members are concerns. We describe novel nonpeptidic PBD-binding inhibitors, termed abbapolins, identified through successful application of the REPLACE strategy and demonstrate their potent antiproliferative activity in prostate tumors and other cell lines. Furthermore, abbapolins show PLK1-specific binding and inhibitory activity, as measured by a cellular thermal shift assay and an ability to block phosphorylation of TCTP, a validated target of PLK1-mediated kinase activity. Additional evidence for engagement of PLK1 was obtained through the unique observation that abbapolins induce PLK1 degradation in a manner that closely matches antiproliferative activity. Moreover, abbapolins demonstrate antiproliferative activity in cells that are dramatically resistant to ATP-competitive PLK1 inhibitors.

Antifungal Activity of Chemical Constituents from Piper pesaresanum C. DC. and Derivatives against Phytopathogen Fungi of Cocoa

In this study, the antifungal potential of chemical constituents from Piper pesaresanum and some synthesized derivatives was determined against three phytopathogenic fungi associated with the cocoa crop. The methodology included the phytochemical study on the aerial part of P. pesaresanum, the synthesis of some derivatives and the evaluation of the antifungal activity against the fungi Moniliophthora roreri, Fusarium solani and Phytophthora sp. The chemical study allowed the isolation of three benzoic acid derivatives (1-3), one dihydrochalcone (4) and a mixture of sterols (5-7). Seven derivatives (8-14) were synthesized from the main constituents, of which compounds 9, 10, 12 and 14 are reported for the first time. Benzoic acid derivatives showed strong antifungal activity against M. roreri, of which 11 (3.0 ± 0.8 µM) was the most active compound with an IC₅₀ lower compared with positive control Mancozeb^® (4.9 ± 0.4 µM). Dihydrochalcones and acid derivatives were active against F. solani and Phytophthora sp., of which 3 (32.5 ± 3.3 µM) and 4 (26.7 ± 5.3 µM) were the most active compounds, respectively. The preliminary structure-activity relationship allowed us to establish that prenylated chains and the carboxyl group are important in the antifungal activity of benzoic acid derivatives. Likewise, a positive influence of the carbonyl group on the antifungal activity for dihydrochalcones was deduced.

A systematic review of botany, phytochemicals and pharmacological properties of "Hoja sant a" (Piper auritum Kunth)

Hoja santa (Piper auritum) refers to an important presence in Mexican cuisine. The information of this review article was gathered from several electronic sources such as Scopus, Medline, Scielo, ScienceDirect, SciFinder, Web of Science, Google Scholar and Lilacs. Phytochemical studies have revealed the presence of benzoic acid derivatives, phenylpropanoids and triterpenoids, while the essential oils have shown its richness in safrole, hence it has several activities, such as antioxidant, toxicity, insecticidal, anti-diabetic and cytotoxic properties. This review is expected to draw the attention of medical professionals and the general public towards P. auritum as well as to open the door for detailed research in the future.

Design, synthesis and evaluation of 3-amide-5-aryl benzoic acid derivatives as novel P2Y14R antagonists with potential high efficiency against acute gouty arthritis

P2Y₁₄ nucleotide receptor plays important roles in series of physiological and pathologic events especially associated with immune and inflammation. Based on the 3-amide benzoic acid scaffold reported by our group previously, a series of 5-aryl-3-amide benzoic acid derivatives were designed as novel P2Y₁₄ antagonists with improved pharmacokinetic properties. Among which compound 11m showed most potent P2Y₁₄ antagonizing activity with an IC₅₀ value of 2.18 nM, furnishing greatly improved water solubility and bioavailability compared with PPTN. In MSU-induced acute gouty arthritis model in mice, 11m exerted promising in vivo efficacy in alleviating mice paw swelling and inflammatory infiltration. Mechanistically, compound 11m notably blocked pyroptosis of macrophages through inhibiting NLRP3 inflammasome activation. This work may contribute to the identification of potential therapeutic agents to intervene in acute gouty arthritis.

Structure-Based Virtual Screening of New Benzoic Acid Derivatives as Trypanosoma cruzi Trans-sialidase Inhibitors

BACKGROUND

Chagas disease, caused by the parasite Trypanosoma cruzi, represents a worldwide epidemiological, economic, and social problem. In the last decades, the trans-sialidase enzyme of Trypanosoma cruzi has been considered an attractive target for the development of new agents with potential trypanocidal activity.

OBJECTIVE

In this work, the aim was to find new potential non-sugar trans-sialidase inhibitors using benzoic acid as a scaffold.

METHODS

A structure-based virtual screening of the ZINC15 database was carried out. Additionally, the enzyme and trypanocidal activity of the selected compounds was determined.

RESULTS

The results of this work detected 487 compounds derived from benzoic acid as potential transsialidase inhibitors with a more promising binding energy value (< -7.7 kcal/mol) than the known inhibitor 2,3-dehydro-2-deoxy-N-acetylneuraminic acid (DANA). In particular, two lead compounds, V1 and V2, turned out to be promising trans-sialidase inhibitors. Even though the trypanocidal activity displayed was low, these compounds showed trans-sialidase inhibition values of 87.6% and 29.6%, respectively.

CONCLUSION

Structure-based virtual screening using a molecular docking approach is a useful method for the identification of new trans-sialidase inhibitors.

pH-responsive polymeric micelles self-assembled from benzoic-imine-containing alkyl-modified PEGylated chitosan for delivery of amphiphilic drugs

In order to efficiently promote loading efficiency and aqueous photostability of indocyanine green (ICG), an amphiphilic tricarbocyanine dye, the polysaccharide-based nanomicelles utilized as a vehicle for ICG were fabricated by self-assembly of the amphiphilic benzoic-imine-containing PEGylated chitosan/4-(dodecyloxy)benzaldehyde (DBA) conjugates in aqueous solution of pH 7.4. The resulting polymeric micelles were characterized to have a hydrophobic hybrid chitosan/DBA core surrounded by hydrophilic PEG shells. Importantly, the encapsulation of ICG into the hybrid chitosan/DBA core of polymeric micelles by the combined hydrophobic and electrostatic interactions not only promoted the ICG loading but also enhanced its aqueous photostability. With the pH of micelle suspension being reduced from 7.4 to 5.0, upon acid-triggered cleavage of benzoic-imine bonds between chitosan and DBA as well as the extending of the protonated chitosan segments from hybrid cores toward aqueous phase, the rather hydrophobic DBA-rich core was formed within micelles, thereby leading to shrinking of the polymeric micelles. The robust ICG-loaded polymeric micelles showed several superior properties including the inhibition of ICG leakage under the mimic physiological and acidic conditions, favorable biocompatibility and photo-activated hyperthermia effect. This work suggests that the pH-responsive ICG-carrying chitosan-based micelles display great potential in cancer theranostic.

Five Novel Non-Sialic Acid-Like Scaffolds Inhibit In Vitro H1N1 and H5N2 Neuraminidase Activity of Influenza a Virus

Neuraminidase (NA) of influenza viruses enables the virus to access the cell membrane. It degrades the sialic acid contained in extracellular mucin. Later, it is responsible for releasing newly formed virions from the membrane of infected cells. Both processes become key functions within the viral cycle. Therefore, it is a therapeutic target for research of the new antiviral agents. Structure–activity relationships studies have revealed which are the important functional groups for the receptor–ligand interaction. Influenza virus type A NA activity was inhibited by five scaffolds without structural resemblance to sialic acid. Intending small organic compound repositioning along with drug repurposing, this study combined in silico simulations of ligand docking into the known binding site of NA, along with in vitro bioassays. The five proposed scaffolds are N-acetylphenylalanylmethionine, propanoic 3-[(2,5-dimethylphenyl) carbamoyl]-2-(piperazin-1-yl) acid, 3-(propylaminosulfonyl)-4-chlorobenzoic acid, ascorbic acid (vitamin C), and 4-(dipropylsulfamoyl) benzoic acid (probenecid). Their half maximal inhibitory concentration (IC₅₀) was determined through fluorometry. An acidic reagent 2′-O-(4-methylumbelliferyl)-α-dN-acetylneuraminic acid (MUNANA) was used as substrate for viruses of human influenza H1N1 or avian influenza H5N2. Inhibition was observed in millimolar ranges in a concentration-dependent manner. The IC₅₀ values of the five proposed scaffolds ranged from 6.4 to 73 mM. The values reflect a significant affinity difference with respect to the reference drug zanamivir (p < 0.001). Two compounds (N-acetyl dipeptide and 4-substituted benzoic acid) clearly showed competitive mechanisms, whereas ascorbic acid reflected non-competitive kinetics. The five small organic molecules constitute five different scaffolds with moderate NA affinities. They are proposed as lead compounds for developing new NA inhibitors which are not analogous to sialic acid.

Complete Genome Sequence and Biodegradation Characteristics of Benzoic Acid-Degrading Bacterium Pseudomonas sp. SCB32

Allelochemicals are metabolites produced by living organisms that have a detrimental effect on other species when released into the environment. These chemicals play critical roles in the problems associated with crop replanting. Benzoic acid is a representative allelochemical found in root exudates and rhizosphere soil of crops and inhibits crop growth. The bioremediation of allelochemicals by microorganisms is an efficient decontamination process. In this research, a bacterial strain capable of degrading benzoic acid as the sole carbon source was isolated. The genome of the strain was sequenced, and biodegradation characteristics and metabolic mechanisms were examined. Strain SCB32 was identified as Pseudomonas sp. based on 16S rRNA gene analysis coupled with physiological and biochemical analyses. The degradation rate of 800 mg L-1 benzoic acid by strain SCB32 was greater than 97.0% in 24 h. The complete genome of strain SCB32 was 6.3 Mbp with a GC content of 64.6% and 5960 coding genes. Potential benzoic acid degradation genes were found by comparison to the KEGG database. Some key intermediate metabolites of benzoic acid, such as catechol, were detected by gas chromatography-mass spectrometry. The biodegradation pathway of benzoic acid, the ortho pathway, is proposed for strain SCB32 based on combined data from genome annotation and mass spectrometry. Moreover, the benzoic acid degradation products from strain SCB32 were essentially nontoxic to lettuce seedlings, while seeds in the benzoic acid-treated group showed significant inhibition of germination. This indicates a possible application of strain SCB32 in the bioremediation of benzoic acid contamination in agricultural environments.