Acid Benzyl Ester Research Articles

Exploring the pyrolytic degradation of seventeen phthalate esters using the non-targeted regions of interest-multivariate curve resolution (ROIMCR) chemometric method

The global use of phthalate esters (PAEs) in plastic production entails a need for developing effective remediation strategies to minimize exposure and health risks. In this study, pyrolysis degradation processes are evaluated for 17 different PAEs that were analyzed by high-resolution gas chromatography-mass spectrometry (Pyr-GC-Orbitrap-MS) at different temperatures (300 °C, 400 °C, 500 °C, 600 °C, 700 °C, 800 °C) both in electron ionization (EI) and positive chemical ionization (PCI) mode. All the analytical data generated have been processed with the Regions of Interest Multivariate Curve Resolution (ROIMCR) chemometrics method. A preliminary selection of the Mass Spectrometry Regions of Interest (ROIs) coupled to a bilinear factor decomposition method (MCR-ALS) allowed the identification of 4 principal components, which were used to define the thermal degradation process. ROIMCR method is a powerful tool for non-targeted analysis which allows the resolution of the elution and spectral profiles of the different constituents present in the analyzed samples, which were confirmed using PCI. Moreover, ROIMCR was used to resolve and identify the different products generated during the studied degradation processes. As a result, 10 new thermal degradation products were identified in the analysis of the different sample sets. Finally, the degradation efficiencies higher than 99.8 % were obtained for all the PAEs at 800 °C, except for benzoic acid-benzyl ester, whose removal efficiency decreased to 94.8 %. As phthalates are widespread and toxic compounds for the environment and for humans, there is a need for new remediation technologies. This study provides new knowledge to understand their elimination through thermal processes. We combine mass spectrometric data with powerful chemometric processing to determine the removal efficiency, to understand the degradation process and to identify the degradation compounds formed through thermal decomposition.

Four odorants for olfactory training are enough: a pilot study

Background: Olfactory training (OT) is commonly used for the treatment of olfactory disorders. Nevertheless, there is an ongoing debate about the most effective OT regimen. We aimed to compare the effects of OT with 7 items (rose, lemon, eucalyptus, cloves, stewed apple, balm, mint) to 4-item-OT (rose, lemon, eucalyptus, cloves) over 3 months. Methods: Participants were 40 patients with olfactory dysfunction receiving 4-item-OT or 7-item-OT and 60 gender- and age-matched individuals with normal sense of smell receiving no OT, 4-item-OT, or 7-item-OT. Before and after the OT we assessed n-butanol odor thresholds, discrimination, and identification (TDI score), additionalthresholds for (R)-(-)-carvone, β-damascenone, salicyclic acid benzylester, the degree of phantosmia and parosmia, cognitive function, and ratings of olfactory function. Results: In both patient groups, the TDI score increased with the use of OT, regardless of the number of odors used (p < 0.001; 3.48 ± 4.21 and lower than control groups). The clinically significant increase of 5.5 points in TDI score correlated with change of ratings of parosmia (r 0.62; p < 0.01) and with ratings of olfactory dysfunction (r = 0.51; p < 0.05). Conclusion: Concluding, OT over a 3-months period with 4 or 7 odors appears to produce similar results, although the sample size has to be considered.

Synthesis and anticancer evaluation of new lupane triterpenoid derivatives containing various substituent at the 2 or 3 position

Betulonic acid benzyl ester 1 has been subjected to a series of structural modifications for the purpose of new triterpenoid synthesis and evaluating for anticancer activity. The one-pot two step synthesis of 2α-(aminomethyl)betulinic acid benzyl ester derivatives 3a–f (yield 46–69 %) was achieved by the Mannich reaction of compound 1 with methyleneiminium salts, generated in situ from N,N-disubstituted bis(amino)methanes 2a–f by the action of acetyl chloride in dichloromethane, and subsequent reduction of aminomethylation products with sodium borohydride. Minor 2β-(aminomethyl) triterpenoids 4c,d,f were also isolated (yield 6–15 %). We found, that the stereoselective reaction of triterpenoid 1 with acetylides, generated at –78 °C from alkynes in the presence of n-BuLi, has been useful and noteworthy as the key step in providing of new alkyne substituted triterpenoids – benzyl 3-alkynyl-3-deoxy-2(3),20(29)-lupadiene-28-oates or 3-deoxy-2(3)-dehydro-28-oxoallobetulin derivative. The new compounds were examined for anticancer activity against the human cell lines (MTT assay). All tested derivatives were non-toxic on human fibroblasts. The 3‐(phenylethynyl)lupa-2(3),20(29)-diene 9 showed selective cytotoxicity on cervical cancer cell lines. Tumor cells death trigged by the most active compound 4f resulted from apoptotic processes. These data make the series of synthesized 2 or 3 substituted lupane derivatives as promising compounds with anticancer potential.

Anthelmintic Activity of Ethanolic and Aqueous Extracts of Khaya grandifoliola Stem Bark against Heligmosomoides polygyrus: In Vitro and In Silico Approaches.

Parasitic infection remains a serious health trade for humans and livestock. The purpose of this study was to present scientific proof of the anthelmintic properties of Khaya grandifoliola, which the native population uses to cure helminthiasis. Fresh Heligmosomoides polygyrus eggs were isolated from faecal samples of experimentally infected mice. The faecal material was cultured, and L1 and L2 larval stages were recovered after 48 and 120 hours, respectively. Using the worm microtracker, the anthelminthic efficacy of the extracts against H. polygyrus was assessed. Two different extracts (aqueous and ethanol extracts) were prepared. For the ovicidal and larvicidal activities, 100 µL of various concentrations of plant extracts, levamisole and 1.5% dimethyl sulfoxide (DMSO), were introduced into a 96-well microplate titer followed by the addition of 100 µL of embryonated eggs (60 eggs) for the ovicidal activity and 100 µL of L 1 or L 2 larvae (50 larvae) for the larvicidal activity. The movement of the worm was monitored for 24 hours in the worm microtracker at 27°C. The Glide module of the Schrodinger Maestro software was used to perform docking studies. For the aqueous extracts, the highest percentage of inhibition of hatching was 42.77 ± 12% at 7.5 mg/mL. The IC50 values for the ethanol (0.36 mg/mL) extract showed that the ethanol extract had a good inhibitory effect on the ability of parasites to hatch from eggs. The inhibition percentage of L1 larvae motility at 7.5 mg/mL was 98.0 ± 1.66% and 83.33 ± 1.66% for ethanol and aqueous extracts, respectively. The negative controls, distilled water and 1.5% DMSO, had no inhibitory impact on larvae. On L1-larvae, the drug of choice levamisole (positive control) had the highest percentage effect (100.0%). Six compounds had the highest docking score and their interactions with the receptor as well. Grandiamide A interacts most with tyrosine, glycine, phenylalanine, asparagine, and serine, and its benzene ring and oxygens inhibit these receptors. Carbonyl and hydroxyl (OH) groups connect grandiamide D to asparagine, isoleucine, and phenylalanine, respectively. By donating hydrogen to the receptor through OH groups, D-glucopyranose-6-phosphate also forms relatively strong hydrogen bonds with its oxygen-bound phosphorus and the receptor. 1-O-deacetylkhayanolide E interacts most with serine and glutamic acid. The carbamic acid benzyl ester of carbamic acid [(1S)-1-phenyl-2-[(4-methylphenyl) sulfinyl] ethyl] interacts most with the receptor with carbonyl groups and with asparagine and serine. With its abundant hydroxide, D-mannitol acts as a hydrogen donor and acceptor and interacts most strongly with amino acids such as glycine, asparagine, aspartic acid, alanine, and glutamic acid. K. grandifoliola extracts possess anthelminthic properties. However, in vivo studies are still necessary to demonstrate the effectiveness of this plant for the treatment of helminthiasis.

A novel pour point depressant with diesel cold-flow properties: Performance evaluation of benzene-containing ternary copolymers

The addition of pour point depressants (PPDs) represents the most direct and efficient approach for improving the cold-flow properties of diesel. Nevertheless, the high doses of additives have consistently been a constraining factor. To address this challenge, the study synthesized tetradecyl methacrylate–N-hydroxymethacrylamide–benzyl acrylate (C14MC–NMA–BA), tetradecyl methacrylate–N-hydroxymethacrylamide–4-pentenoic acid benzyl ester (C14MC–NMA–PB), and tetradecyl methacrylate–N-hydroxymethacrylamide–10-undecenoic acid benzyl ester (C14MC–NMA–UB) at various molar ratios (1:1:1, 5:1:1, 10:1:1, 15:1:1, and 20:1:1) as PPDs for diesel. The aim of these PPDs is to efficiently improve the cold-flow properties of diesel at low doses. The cold filter plugging point (CFPP) and solidification point (SP) of diesel were tested before and after treatment with PPDs. The results confirmed that C14MC–NMA–UB with longer carbon chains exhibited superior performance compared to C14MC–NMA–PB and C14MC–NMA–BA. Considering both cost-effectiveness and performance metrics, 400 ppm C14MC–NMA–UB (5:1:1) was identified as the optimal choice for significantly enhancing diesel cold-flow properties, leading to reductions of CFPP and SP by 11 °C and 25 °C, respectively. Furthermore, the study delved into the inhibitory mechanisms of PPDs by examining the crystallization behavior of diesel at low temperatures, utilizing techniques such as differential scanning calorimetry, viscosity-temperature profiles, and polarized optical microscopy.

Molecular design and synthesis of dithiocarbazate-based potential biomaterials: Crystal structure, apoptotic activity and protein binding studies

A series of organic based heterocyclic dithiocarbazate ligands N'-(1-methyl-1H-imidazol-2-ylmethylene)-hydrazinecarbodithioic acid methyl ester (L1), N'-(1-methyl-1H-imidazol-2-ylmethylene)-hydrazinecarbodithioic acid benzyl ester (L2), N'-[1-(1H-benzoimidazol-2-yl)-ethylidene]-hydrazinecarbodithioic acid methyl ester (L3) and N'-[1-(1H-benzoimidazol-2-yl)-ethylidene]-hydrazinecarbodithioic acid benzyl ester (L4) has been prepared along with characterization by various spectroscopic techniques (IR, 1H and 13C NMR, mass and UV–Visible) and thermal analysis. Single crystal X-ray diffraction analysis is used to determine the crystal structure of the synthesized ligands L1 and L3 crystallizes as orthorhombic and monoclinic crystals, respectively. Fluorescence spectrophotometry is used to study the interaction of the ligands with bovine serum albumin (BSA) and the quenching of BSA followed a static type. MTT assay against H520 (Squamous cell lung carcinoma) cell reveals that L1 and L3 ligands shows higher cytotoxic value than the remaining L2 and L4 ligands and could be a better choice as chemotherapeutic agent. Apoptotic activity was assayed using AO/EB staining and Hoechst 33258 staining, the early apoptotic features such as cell shrinkage and condensation were majorly observed in cells treated with all four ligands.

Anti-inflammatory activity of caffeic acid derivatives from Ilex rotunda.

Ilex rotunda Thunb. has been used in traditional medicine for treating rheumatoid arthritis, relieving pain and indigestion. In the present study, we isolated three new caffeic acid benzyl ester (CABE) analogs (1-3) along with eight known compounds (4-11) from the extract of I. rotunda. The absolute configuration of α-hydoxycarboxylic acid in 1 was assigned with the phenylglycine methyl ester (PGME) method. We further investigated their anti-inflammatory activities in lipopolysaccharide (LPS)-induced macrophages (RAW 264.7) cells. Among them, compounds 2-4, 7, 8, 10, and 11 suppressed the production of nitric oxide (NO), pro-inflammatory mediators. It was additionally confirmed that the anti-inflammatory effect of active compound 2 was through significant suppression of cytokines, including interleukin (IL)-6, IL-1β, tumor necrosis factor (TNF)-α, and IL-8 in LPS-stimulated RAW 264.7 cells and colon epithelial (HT-29) cells. Western blot analysis revealed that compound 2 decreased the LPS-induced expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), and phosphorylated extracellular regulated kinase (pERK)1/2. The following molecular docking simulations showed the significant interactions of compound 2 with the iNOS protein. These results suggested that the compound 2 can be used as potential candidate for treating inflammatory diseases such as inflammatory bowel disease (IBD).

Abstract 106: Diclofenac hybrids with oleanolic acid oximes modulate key signaling pathways in pancreatic cancer cells

Abstract Pancreatic cancer is characterized by constitutive activation of mitogen-activated protein kinases (MAPKs) like JNK and p38 determining its malignant phenotypes. Overexpression of NF-κB and COX-2 involved in inflammation contributes to increased cell growth and invasiveness. The latter might be related to the activated AKT pathway. Nonsteroidal anti-inflammatory drugs were suggested for pancreas cancers prophylaxis. Naturally occurring oleanolic acid (OA) was shown to possess anti-inflammatory and anti-tumorigenic activities. Coupling its analogs with NSAIDs may enhance this effect. Our study aimed to evaluate the effect of two oleanolic acid oximes derivatives conjugated with diclofenac (DCL), 4c (3-diclofenacoxyiminoolean-12-en-28-oic acid benzyl ester) and 4d (3-diclofenacoxyiminoolean-12-en-28-oic acid morpholide) on inflammation-related pathways, MAPK and NF-κB, cell cycle arrest and ROS formation in PSN-1 pancreatic cancer cells. PSN-1 cells were incubated with DCL, 4c or 4d at the concentration of 30µM. Activation of NF-κB was assessed by measuring binding of its p50 and p65 subunits to DNA using ELISA method. Their nuclear concentrations were determined by Western blot. RT-PCR was used to evaluate NF-κB subunits and COX-2 mRNA levels. Bead-based immunoassay determined the cytosolic levels of p38, JNK, CREB, AKT, P70S6K and STAT3 proteins. Cell cycle distribution and ROS formation were assessed using flow cytometry. Conjugate 4d significantly reduced nuclear level of p65 subunit and its mRNA expression, although compound 4c had more significant impact on COX-2 expression. Both derivatives significantly diminished p65 DNA binding, but only 4d had significant effect on p50. Both compounds reduced ROS production, but neither of them affected the cell cycle arrest. We observed decreased cytosolic AKT level along with increased levels of unphosphorylated JNK and p38 kinases which may have an antagonistic effect on proliferation by reducing activity of inflammatory mediators acting as tumor promoters. AKT decrease after treatment with 4d derivative might be the cause of increased unphosphorylated CREB level. Accumulation of p38 and JNK in cytosol could be a result of decreased ROS production and/or cause increased CREB protein level. Additionally, increased STAT3 cytosolic level suggests inhibition of mTORC1 pathway that explains reduced p70S6 kinase. Overall, these results suggest that OAO-DCL morpholide conjugate may affect both NF-κB and MAPK signaling pathways in pancreatic cancer cells. Further studies are required to explain detailed mechanism of these modifications. Funding: Studies were supported by Polish National Science Centre grant 2016/21/B/NZ7/01758. Acknowledgments: Authors thank Dr. Gary Gorbsky, Chair of Cell Cycle &amp; Cancer Biology Program in Oklahoma Medical Research Foundation for supporting financing Maria Narozna conference participation. Citation Format: Maria Narozna, Violetta Krajka-Kuzniak, Robert Kleszcz, Wanda Baer-Dubowska. Diclofenac hybrids with oleanolic acid oximes modulate key signaling pathways in pancreatic cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 106.

In situ formation of J-aggregate in the tumor microenvironment using acidity responsive polypeptide nanoparticle encapsulating galactose-conjugated BODIPY dye for NIR-II phototheranostics.

Through the activation of packing arrangements of dyes to modulate their photophysical and/or photochemical properties, not only new NIR-II dyes but tumor-specific NIR-II imaging and therapy can also be achieved. Herein, we designed an acid-responsive polypeptide nanoparticle (P-ipr@Gal) encapsulated with a pH-sensitive amphiphilic polypeptide (P-ipr) as a carrier for the galactose-conjugated BODIPY (Gal-BDP) dye. When P-ipr@Gal NPs are enriched in tumor regions by the EPR effect, the acidic microenvironment (pH 6.4-6.8) promotes the disintegration of P-ipr@Gal nanomicelles and the release of sufficient Gal-BDP. The protonation of the julolidine nitrogen of the Gal-BDP dye switched on the molecular stacking transformation from the H-aggregate to J-aggregate. The J-aggregate significantly enhanced the redshift absorption and emission intensity, which enhanced the fluorescence brightness and photothermal therapeutic effect in the tumor region. We also prepared J-aggregates PAsp@Gal with non-acidic responsive polyaspartic acid benzyl esters (PAsp) encapsulated Gal-BDP, which remained "always-on" with J-aggregate characteristics. The P-ipr@Gal (or PAsp@Gal) J-aggregate has a maximum emission peak redshifted to nearly 1064 nm, with a 3.5-fold increase in the emission intensity compared to the H-aggregate at pH 7.4. Based on the effective accumulation of tumor sites and considerable PCE (>40%), P-ipr@Gal nanoparticles have a lower background and higher tumor background ratio, which makes them a potential NIR-II imaging-guided photothermal therapy agents.

Conjugation of Diclofenac with Novel Oleanolic Acid Derivatives Modulate Nrf2 and NF-κB Activity in Hepatic Cancer Cells and Normal Hepatocytes Leading to Enhancement of Its Therapeutic and Chemopreventive Potential.

Combining NSAIDs with conventional therapeutics was recently explored as a new strategy in cancer therapy. Our earlier studies showed that novel oleanolic acid oximes (OAO) conjugated with aspirin or indomethacin may enhance their anti-cancer potential through modulation of the Nrf2 and NF-κB signaling pathways. This study focused on the synthesis and biological evaluation of four diclofenac (DCL)–OAO derivative conjugates in the context of these pathways’ modification and hepatic cells survival. Treatment with the conjugates 4d, 3-diclofenacoxyiminoolean-12-en-28-oic acid morpholide, and 4c, 3-diclofenacoxyiminoolean-12-en-28-oic acid benzyl ester significantly reduced cell viability in comparison to the DCL alone. In THLE-2, immortalized normal hepatocytes treated with these conjugates resulted in the activation of Nrf2 and increased expression in SOD-1 and NQO1, while the opposite effect was observed in the HepG2 hepatoma cells. In both cell lines, reduced activation of the NF-κB and COX-2 expression was observed. In HepG2 cells, conjugates increased ROS production resulting from a reduced antioxidant defense, induced apoptosis, and inhibited cell proliferation. In addition, the OAO morpholide derivative and its DCL hybrid reduced the tumor volume in mice bearing xenografts. In conclusion, our study demonstrated that conjugating diclofenac with the OAO morpholide and a benzyl ester might enhance its anti-cancer activity in HCC.

Abstract 1289: Conjugation of indomethacin with novel oleanolic acid oximes increases its Nrf2 and NF-κB signaling pathways modulating effect in pancreatic cancer cells

Abstract Chronic inflammation is a key factor in the etiology of neoplastic diseases, including pancreatic cancer. Nonsteroidal anti-inflammatory drugs (NSAIDs) were approved for the chemoprevention of colon tumors and suggested for pancreas cancers prophylaxis. Anti-inflammatory and anti-tumorigenic activities are also exerted by naturally occurring and synthetic triterpenoids. Coupling of triterpenoid analogues with NSAIDs may enhance this effect and prevent the unfavorable side effects related to NSAIDs long-term use. In this study novel oleanolic acid oxime (OAO) derivatives conjugated with indomethacin (IND) differing in substitution group at position C-17 were evaluated in the context of their possible modulating effect of Nrf2-ARE and NF-κB signaling pathways in pancreatic cancer cells.PSN-1 cells were incubated for 24h with IND and OAO-IND derivatives at the concentrations of 10µM and 20µM selected based on the results of the MTT assay. The activation of Nrf2 and NF-κB was assessed by the evaluation of its translocation into the nucleus and binding to specific DNA sequences by the ELISA assay. Expression of Nrf2, SOD-1, NF-κBp50, NF-κBp65 and COX-2 was evaluated by RT-PCR and Western blot methods.Cell viability was affected mostly by 3-indomethacinoxyiminoolean-12-en-28-oic acid morpholide and 3-indomethacinoxyiminoolean-en-28-oic acid benzyl ester. The level of Nrf2 in the nucleus and binding to ARE sequence was decreased in PSN-1 cells, similarly as was NF-κBp50 and NF-κBp65 binding and nuclear accumulation. As result of diminished activation of these transcription factors decreased expression of SOD-1 and COX-2 i.e. mRNA and protein levels were found. These results indicate that the OAO-IND derivatives, particularly morpholide and benzyl ester conjugates, are more potent suppressors of NF-κB signaling pathway than IND alone. Moreover, conjugation of IND with novel OAO may protect cancer cells against chemoresistance through inhibition of the Nrf2-ARE pathway. Those novel compounds might be considered the potential modulators of hepatocellular carcinoma therapy and chemopreventive agents. Funding: This work was supported by Polish National Science Centre, grant 2016/21/B/NZ7/01758. Citation Format: Wanda Baer-Dubowska, Maria Narozna, Violetta Krajka-Kuźniak, Barbara Bednarczyk-Cwynar. Conjugation of indomethacin with novel oleanolic acid oximes increases its Nrf2 and NF-κB signaling pathways modulating effect in pancreatic cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 1289.

Activity of Compounds from Temperate Propolis against Trypanosoma brucei and Leishmania mexicana

Ethanolic extracts of samples of temperate zone propolis, four from the UK and one from Poland, were tested against three Trypanosoma brucei strains and displayed EC50 values < 20 µg/mL. The extracts were fractionated, from which 12 compounds and one two-component mixture were isolated, and characterized by NMR and high-resolution mass spectrometry, as 3-acetoxypinobanksin, tectochrysin, kaempferol, pinocembrin, 4′-methoxykaempferol, galangin, chrysin, apigenin, pinostrobin, cinnamic acid, coumaric acid, cinnamyl ester/coumaric acid benzyl ester (mixture), 4′,7-dimethoxykaempferol, and naringenin 4′,7-dimethyl ether. The isolated compounds were tested against drug-sensitive and drug-resistant strains of T. brucei and Leishmania mexicana, with the highest activities ≤ 15 µM. The most active compounds against T. brucei were naringenin 4′,7 dimethyl ether and 4′methoxy kaempferol with activity of 15–20 µM against the three T. brucei strains. The most active compounds against L. mexicana were 4′,7-dimethoxykaempferol and the coumaric acid ester mixture, with EC50 values of 12.9 ± 3.7 µM and 13.1 ± 1.0 µM. No loss of activity was found with the diamidine- and arsenical-resistant or phenanthridine-resistant T. brucei strains, or the miltefosine-resistant L. mexicana strain; no clear structure activity relationship was observed for the isolated compounds. Temperate propolis yields multiple compounds with anti-kinetoplastid activity.

Very-Long-Chain Wax Constituents from Primula veris and P. acaulis: Does the Paradigm of Non-Branched vs. Branched Chain Dominance Universally Hold in all Plant Taxa?

Herein n-, iso- and anteiso-series of very-long-chained (VLC) alkanes (C21 -C35 ), fatty acid benzyl esters (FABEs; C20 -C32 ), and 2-alkanones (C23 -C35 ) were identified in the wax of Primula veris L. and P. acaulis (L.) L. (Primulaceae). For the very first time in a sample of natural origin, the presence of iso- and anteiso-VLC FABEs and 2-alkanones was unequivocally confirmed by synthetic work, derivatization, and NMR. It should be noted that the studied species produced unusually high amounts of branched wax constituents (e. g., >50 % of 2-alkanones were branched isomers). The domination of iso-isomers, probably biosynthesized from leucine-derived starters, is a unique feature in the Plant Kingdom. The plant organ distribution of these VLC compounds in P. acaulis samples (different habitats and phenological phases) pointed to their possible ecological value. This was supported by a eutectic behavior of binary blends of FABEs and alkanes, as well as by high UV-C absorption by FABEs.

Phenolic Compounds of Propolis Alleviate Lipid Metabolism Disorder.

Lipid metabolism disorder is one of the significant risk factors for a multitude of human diseases and has become a serious threat to human health. The present study aimed to evaluate the effects of phenolics from poplar-type propolis on regulating lipid metabolism by using cell models of steatosis induced by palmitic acid (PA). Our study shows that phenolic esters have higher lipid-lowering activities than phenolic acids, especially for three caffeic acid esters, including caffeic acid phenethyl ester (CAPE), caffeic acid cinnamyl ester (CACE), and caffeic acid benzyl ester (CABE). Most notably, CACE presents prominent properties to prevent intracellular lipid accumulation and to amend extracellular adipokine secretion abnormalities. In addition, our results firstly reveal that CACE can alleviate lipid metabolism disorder through mediating protein kinase RNA-like endoplasmic reticulum kinase (PERK), activating transcription factor 6 (ATF6) signaling pathway-associated protein expression, suppressing endoplasmic reticulum (ER) stress, and activating peroxisome proliferator-activated receptors (PPARs) by distinct upregulation of PPARα and downregulation of PPARγ.

Diverse protein manipulations with genetically encoded glutamic acid benzyl ester.

Site-specific modification of proteins has significantly advanced the use of proteins in biological research and therapeutics development. Among various strategies aimed at this end, genetic code expansion (GCE) allows structurally and functionally distinct non-canonical amino acids (ncAAs) to be incorporated into specific sites of a protein. Herein, we genetically encode an esterified glutamic acid analogue (BnE) into proteins, and demonstrate that BnE can be applied in different types of site-specific protein modifications, including N-terminal pyroglutamation, caging Glu in the active site of a toxic protein, and endowing proteins with metal chelator hydroxamic acid and versatile reactive handle acyl hydrazide. Importantly, novel epigenetic mark Gln methylation is generated on histones via the derived acyl hydrazide handle. This work provides useful and unique tools to modify proteins at specific Glu or Gln residues, and complements the toolbox of GCE.

The Effect of Novel Oleanolic Acid Oximes Conjugated with Indomethacin on the Nrf2-ARE And NF-κB Signaling Pathways in Normal Hepatocytes and Human Hepatocellular Cancer Cells.

Nrf2 and NF-κB play a key role in inflammation-driven cancers. Conjugation of anti-inflammatory drugs with oleanolic acid oxime (OAO) may enhance their therapeutic potential as a result of downregulation of these pathways. Novel OAO derivatives conjugated with indomethacin (IND) were synthesized, and their effect on the activation and expression of Nrf2 and NF-κB in HepG2 hepatoma cells and THLE-2 immortalized normal hepatocytes was evaluated in relation to cell cycle arrest and apoptosis. Treatment with OAO–IND conjugates reduced the activation of Nrf2 and NF-κB and the expression of their active forms in HepG2 cells, while in normal hepatocytes, the activation of Nrf2 was increased and NF-κB diminished. Compounds 3d, 3-indomethacinoxyiminoolean-12-en-28-oic acid morpholide, and 3c, 3-indomethacinoxyiminoolean-12-en-28-oic acid benzyl ester, were the most efficient. In THLE-2 cells, as opposed to HepG2 cells, the expressions of SOD-1 and NQO1 were significantly enhanced after treatment with these compounds. The COX-2 expression was diminished in both cell lines. OAO–IND derivatives affected the cell cycle arrest at G2/M, leading to increased apoptosis and increased number of resting HepG2 cells. Therefore, the conjugation of IND with OAO derivatives may preserve cancer cells against chemoresistance through the inhibition of the Nrf2-ARE pathway and NF-κB and, at the same time, exert a chemopreventive effect in normal hepatocytes.

Intramolecular benzyl cation transfer in the gas-phase fragmentation of protonated benzyl phenyl sulfones.

In this study, the gas-phase fragmentations of protonated benzyl phenyl sulfones were investigated by electrospray ionization tandem mass spectrometry (ESI-MSn ). Upon collisional activation, several characteristic fragment ions were observed, and the similar results occurred with different substituted benzyl phenyl sulfones. A mechanism involving an intramolecular benzyl cation transfer and the formation of intermediate ion was proposed and further identified by density functional theory (DFT) calculations. In addition, a reference compound, benzenesulfinic acid benzyl ester, has been synthesized, and its protonated ion has the same gas-phase behavior as compared to the protonated benzyl phenyl sulfone. This work provides access to some insight into the intramolecular benzyl-transfer reactions of benzyl phenyl sulfones in the gas phase and orients the characteristic peaks in collision-induced dissociation spectrometry (CID-MS).

Efficient and stable inverted perovskite solar cells enabled by inhibition of self-aggregation of fullerene electron-transporting compounds

Fullerene-based electron-transporting layers (ETLs) significantly influence the defect passivation and device performance of inverted perovskite solar cells (PSCs). However, the π-cage structures of fullerenes lead to a strong tendency to self-aggregate, which affects the long-term stability of the corresponding PSCs. Experimental results revealed that [6,6]-phenyl-C61-butyric acid methyl ester (PCBM)-based ETLs exhibit a certain degree of self-aggregation that affects the stability of the device, particularly under continuous irradiation stress. To modulate the aggregation behavior, we replaced a methyl hydrogen of PCBM with a phenyl group to yield [6,6]-phenyl-C61-butyric acid benzyl ester (PCBB). As verified through X-ray crystallography, this minor structural modification results in more non-covalent intermolecular interactions, which effectively enhanced the electron-transporting ability of the PCBB-based ETL and led to an efficiency approaching 20%. Notably, the enhanced intermolecular forces of PCBB suppressed its self-aggregation, and the corresponding device showed significantly improved stability, retaining approximately 90% of its initial efficiency after 600 h under one-sun irradiation with maximum power point tracking. These findings provide a viable approach for the design of new fullerene derivatives to tune their intermolecular interactions to suppress self-aggregation within the ETL for high-performance PSCs.

Fatty acid benzyl esters asbio‐basedplasticizers insilica‐filled solution‐polymerized styrene‐butadienerubber/butadiene rubber composites

AbstractBio‐oil based plasticizers have gained great attention in rubber industry as alternatives of petro‐based plasticizers with high content of polycyclic aromatic hydrocarbons. In this work, five fatty acid benzyl esters were synthesized by the esterification of fatty acids (lauric acid, myristic acid, palmitic acid, stearic acid, and oleic acid, which are obtained after hydrolysis of some vegetable oils) with benzyl alcohol. They were further applied as plasticizers in silica‐filled solution‐polymerized styrene‐butadiene rubber/butadiene rubber (SSBR/BR) composites in order to study the structure‐property relationship, compared with treated distillate aromatic extract (TDAE) as standard. The composites were studied for their processability, curing, static, and dynamic mechanical properties by developing through compatibility between bio‐plasticizers and polymer matrix. The results show that benzyl laurate with suitable hydrocarbon chain length and benzyl oleate with a carbon‐carbon double bond have comparatively improved performance compared to TDAE in the silica‐filled SSBR/BR composites.

Effect of 1‐ethyl‐3‐methylimidazolium acetate on the oxidation of caffeic acid benzyl ester: An electrochemical and theoretical study

AbstractThe effect of the ionic liquid (IL), 1‐ethyl‐3‐methylimidazolium acetate ([emim][AcO]) on the oxidation of (E)‐phenylmethyl‐3‐(3,4‐dihydroxyphenyl)‐2‐propenoate (commonly known as caffeic acid benzyl ester [CABE]) was analyzed through experimental and theoretical methods, such as cyclic voltammetry (CV) and density functional theory (DFT) calculations. The obtained results demonstrated that the AcO− anion promotes the oxidation of the caffeic ester; this is because of the basic character of AcO−, which plays an important role to reduce the amount of energy required for the removal of one electron from the IL‐CABE complex. This suggests that a strong hydrogen bond is formed between this anion and the phenolic H─O. Even the presence of water in the mixture of CABE‐IL does not have a significant effect on the electrooxidation of the complex. Hence, it is possible to infer that CABE is more attached to [emim][AcO] than to the water molecules in the solvation sphere under the experimental conditions evaluated here. Other intermolecular interactions between CABE and IL also contribute to stabilize the resulting complex, e.g., van der Waals and cation‐π interactions, which were evidenced through the theoretical noncovalent interactions (NCI) methodology. The relevant role of basic anions in the extraction of phenolic compounds, using ILs, has been documented in the literature; it should be considered that the strength of the hydrogen bond formed between the phenolic H─O and the IL should not contribute to the oxidation of target compounds.