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1.
Methods Mol Biol ; 2855: 67-84, 2025.
Article in English | MEDLINE | ID: mdl-39354301

ABSTRACT

Untargeted metabolomics is a powerful profiling tool for the discovery of possible biomarkers of disease onset and progression. Analytical pipelines applying liquid chromatography (LC) and mass spectrometry (MS)-based methods are widely used to survey a broad range of metabolites within various metabolic pathways, including organic acids, amino acids, nucleosides, and lipids. Accurate and complete identification of putative metabolites is an ongoing challenge in untargeted metabolomics studies. Highly sensitive instrumentation can result in the detection of adduct and fragment ions that form reproducibly and contain identifiable ions that are difficult to distinguish from metabolic pathway intermediates, which may result in false-positive identification. At concentrations as low as 10 µM, free fatty acids have been found to form homo- and heterodimers in untargeted metabolomics pipelines that resemble the lipid class fatty acid esters of hydroxy fatty acids (FAHFAs), resulting in misidentification. This chapter details a protocol for LC-MS-based untargeted metabolomics using hydrophilic interaction chromatography (HILIC) that specifically aids in distinguishing artifactual fatty acid dimers from endogenous FAHFAs.


Subject(s)
Esters , Fatty Acids , Mass Spectrometry , Metabolomics , Fatty Acids/analysis , Fatty Acids/metabolism , Fatty Acids/chemistry , Chromatography, Liquid/methods , Esters/analysis , Esters/chemistry , Esters/metabolism , Metabolomics/methods , Mass Spectrometry/methods , Artifacts , Dimerization , Hydroxy Acids/analysis , Hydroxy Acids/metabolism , Hydroxy Acids/chemistry , Hydrophobic and Hydrophilic Interactions , Humans , Tandem Mass Spectrometry/methods , Liquid Chromatography-Mass Spectrometry
2.
J Org Chem ; 89(18): 13719-13724, 2024 09 20.
Article in English | MEDLINE | ID: mdl-39257180

ABSTRACT

Peptide alkyl thioesters are versatile reagents in various synthetic applications, commonly generated from peptide hydrazides and thiols. However, a notable limitation is the need for a substantial excess of the thiol reagent, restricting the usage to simple thiols. Here, we introduce an adapted procedure that significantly enhances thioester production with just a minimal thiol excess, facilitating the use of advanced thiol nucleophiles.


Subject(s)
Esters , Hydrazines , Peptides , Sulfhydryl Compounds , Sulfhydryl Compounds/chemistry , Peptides/chemistry , Peptides/chemical synthesis , Esters/chemistry , Hydrazines/chemistry , Molecular Structure
3.
Luminescence ; 39(9): e4890, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39234919

ABSTRACT

Three dyes-diesters of monoimides of perylene-3,4,9,10-tetracarboxylic acid were synthesized in three-stage process: esterification, hydrolysis, and monoimidation as potential fluorescent light-stable colorants for high visibility safety wear. The structure of these compounds was confirmed by 1H nuclear magnetic resonance spectroscopy and mass spectrometry, and their spectroscopic and physicochemical properties were determined. Colorants were applied to dyeing polyester fibre and polystyrene and poly (methyl methacrylate) films. The light, wash, and rubbing fastness of the dyeings were determined, and chromaticity coordinates were measured and discussed.


Subject(s)
Perylene , Polyesters , Polymethyl Methacrylate , Polystyrenes , Polystyrenes/chemistry , Polystyrenes/chemical synthesis , Perylene/chemistry , Perylene/chemical synthesis , Perylene/analogs & derivatives , Polyesters/chemistry , Polyesters/chemical synthesis , Polymethyl Methacrylate/chemistry , Polymethyl Methacrylate/chemical synthesis , Molecular Structure , Esters/chemistry , Imides/chemistry , Imides/chemical synthesis , Coloring Agents/chemistry , Coloring Agents/chemical synthesis , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis
4.
Int J Mol Sci ; 25(17)2024 Sep 08.
Article in English | MEDLINE | ID: mdl-39273679

ABSTRACT

Breast cancer has the highest incidence rate among all malignancies worldwide. Its high mortality is mainly related to the occurrence of multidrug resistance, which significantly limits therapeutic options. In this regard, there is an urgent need to develop compounds that would overcome this phenomenon. There are few reports in the literature that selenium compounds can modulate the activity of P-glycoprotein (MDR1). Therefore, we performed in silico studies and evaluated the effects of the novel selenoesters EDAG-1 and EDAG-8 on BCRP, MDR1, and MRP1 resistance proteins in MCF-7 and MDA-MB-231 breast cancer cells. The cytometric analysis showed that the tested compounds (especially EDAG-8) are inhibitors of BCRP, MDR1, and MRP1 efflux pumps (more potent than the reference compounds-novobiocin, verapamil, and MK-571). An in silico study correlates with these results, suggesting that the compound with the lowest binding energy to these transporters (EDAG-8) has a more favorable spatial structure affecting its anticancer activity, making it a promising candidate in the development of a novel anticancer agent for future breast cancer therapy.


Subject(s)
Breast Neoplasms , Humans , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Female , Drug Resistance, Neoplasm/drug effects , Cell Line, Tumor , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Organoselenium Compounds/pharmacology , Organoselenium Compounds/chemistry , Drug Resistance, Multiple/drug effects , ATP Binding Cassette Transporter, Subfamily G, Member 2/metabolism , ATP Binding Cassette Transporter, Subfamily G, Member 2/antagonists & inhibitors , MCF-7 Cells , Neoplasm Proteins/metabolism , Neoplasm Proteins/antagonists & inhibitors , Molecular Docking Simulation , Multidrug Resistance-Associated Proteins/metabolism , Multidrug Resistance-Associated Proteins/antagonists & inhibitors , Esters/pharmacology , Esters/chemistry , ATP Binding Cassette Transporter, Subfamily B/metabolism , ATP Binding Cassette Transporter, Subfamily B/antagonists & inhibitors
5.
Molecules ; 29(17)2024 Aug 28.
Article in English | MEDLINE | ID: mdl-39274915

ABSTRACT

Phenylpropanoid sucrose esters are a large and important group of natural substances with significant therapeutic potential. This work describes a pilot study of the enzymatic hydroxycinnamoylation of sucrose and its derivatives which was carried out with the aim of obtaining precursors of natural phenylpropanoid sucrose esters, e.g., vanicoside B. In addition to sucrose, some chemically prepared sucrose acetonides and substituted 3'-O-cinnamates were subjected to enzymatic transesterification with vinyl esters of coumaric, ferulic and 3,4,5-trimethoxycinnamic acid. Commercial enzyme preparations of Lipozyme TL IM lipase and Pentopan 500 BG exhibiting feruloyl esterase activity were tested as biocatalysts in these reactions. The substrate specificity of the used biocatalysts for the donor and acceptor as well as the regioselectivity of the reactions were evaluated and discussed. Surprisingly, Lipozyme TL IM catalyzed the cinnamoylation of sucrose derivatives more to the 1'-OH and 4'-OH positions than to the 6'-OH when the 3'-OH was free and the 6-OH was blocked by isopropylidene. In this case, Pentopan reacted comparably to 1'-OH and 6'-OH positions. If sucrose 3'-O-coumarate was used as an acceptor, in the case of feruloylation with Lipozyme in CH3CN, 6-O-ferulate was the main product (63%). Pentopan feruloylated sucrose 3'-O-coumarate comparably well at the 6-OH and 6'-OH positions (77%). When a proton-donor solvent was used, migration of the 3'-O-cinnamoyl group from fructose to the 2-OH position of glucose was observed. The enzyme hydroxycinnamoylations studied can shorten the targeted syntheses of various phenylpropanoid sucrose esters.


Subject(s)
Coumaric Acids , Sucrose , Sucrose/chemistry , Sucrose/metabolism , Coumaric Acids/chemistry , Coumaric Acids/metabolism , Lipase/metabolism , Lipase/chemistry , Cinnamates/chemistry , Cinnamates/metabolism , Substrate Specificity , Esterification , Carboxylic Ester Hydrolases/metabolism , Carboxylic Ester Hydrolases/chemistry , Esters/chemistry , Esters/metabolism , Biocatalysis
6.
Molecules ; 29(17)2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39274962

ABSTRACT

Teicoplanin has been banned in the veterinary field due to the drug resistance of antibiotics. However, teicoplanin residue from the antibiotic abuse of humans and animals poses a threat to people's health. Therefore, it is necessary to develop an efficient way for the highly accurate and reliable detection of teicoplanin from humans, food, and water. In this study, novel imprinted quantum dots of teicoplanin were prepared based on boronate affinity-based precisely controlled surface imprinting. The imprinting factor (IF) for teicoplanin was evaluated and reached a high value of 6.51. The results showed excellent sensitivity and selectivity towards teicoplanin. The relative fluorescence intensity was inversely proportional to the concentration of teicoplanin, in the range of 1.0-17 µM. And its limit of detection (LOD) was obtained as 0.714 µM. The fluorescence quenching process was mainly controlled by a static quenching mechanism via the non-radiative electron-transfer process between QDs and the five-membered cyclic boronate esters. The recoveries for the spiked urine, milk, and water samples ranged from 95.33 to 104.17%, 91.83 to 97.33, and 94.22 to 106.67%, respectively.


Subject(s)
Anti-Bacterial Agents , Boronic Acids , Quantum Dots , Teicoplanin , Quantum Dots/chemistry , Humans , Teicoplanin/chemistry , Teicoplanin/analysis , Boronic Acids/chemistry , Anti-Bacterial Agents/analysis , Anti-Bacterial Agents/chemistry , Spectrometry, Fluorescence/methods , Limit of Detection , Water/chemistry , Molecular Imprinting/methods , Esters/chemistry , Esters/analysis , Electron Transport , Food Contamination/analysis , Food Analysis/methods , Animals , Biosensing Techniques/methods , Milk/chemistry , Fluorescence
7.
J Agric Food Chem ; 72(36): 19891-19903, 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39225266

ABSTRACT

Oat straw, a residue of Avena sativa L., is recognized for its abundance in cellulose, hemicelluloses, and lignin. However, its potential as a source of lipophilic compounds within the framework of a biorefinery concept still remains unexplored. In this study, we conducted an extensive investigation into the content and chemical composition of the lipophilic compounds present in acetone extracts from oat straws of two distinct oat varieties, namely, Karen and Isaura. Furthermore, we examined their seasonal variability in content and composition in straw samples from oats planted in both spring and winter seasons. The extracted lipophilic compounds were predominantly composed of high molecular weight esters (26.0-38.1%), steroids (16.6-24.0%), n-fatty alcohols (10.9-20.7%), n-fatty acids (10.9-16.0%), and n-aldehydes (10.7-15.8%), with lower amounts of n-alkanes (1.1-3.0%), acylglycerides (2.3-3.8%), phytol and phytyl esters (0.6-2.9%), ß-diketones (0.1-2.5%), triterpenoids (0.9-1.2%), tocopherols and tocopheryl esters (0.2-0.7%), 2-hydroxy fatty acids (0.1-0.2%), and n-alkylresorcinols (0.1%). Notably, these different classes of compounds exhibited variations in their contents depending on the oat variety and the specific planting season. Of particular interest was the Karen variety, which presented significant amounts of high molecular weight esters, free fatty acids, and acylglycerols, especially when it was cultivated during the winter season. These findings underline the potential of oat straw as a valuable resource for lipid extraction within a biorefinery context and emphasize the importance of selecting the appropriate variety and season for optimal lipid yield.


Subject(s)
Avena , Fatty Acids , Seasons , Avena/chemistry , Fatty Acids/chemistry , Fatty Acids/analysis , Esters/analysis , Esters/chemistry , Plant Extracts/chemistry , Plant Stems/chemistry , Lipids/chemistry , Lipids/analysis
8.
J Agric Food Chem ; 72(37): 20690-20703, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39230960

ABSTRACT

Sorghum, a globally grown gluten-free cereal, is used mainly as an animal feed in developed countries regardless of its potential for human consumption. In this study, we utilized nontargeted lipidomics to thoroughly analyze, compare, and characterize whole-grain lipids in six sorghum cultivars (cv) grown in a single field trial in Australia: Buster, Bazley, Cracker, Liberty, MR43, and Tiger. In total, 194 lipid molecular species representing five major lipid classes were identified. Multivariate analysis unveiled distinct lipid profiles among the cultivars. The most distinct lipid profile belonged to cv. MR43. The lower ω-6 to ω-3 ratio and optimal P/S ratio in cv. Bazley reflect this as a valuable source of balanced essential fatty acids in the diet. The novel bioactive lipids known as FAHFAs (fatty acid esters of hydroxy fatty acids) were identified and characterized in sorghum grains. These findings further emphasize the potential of whole-grain sorghum as a basis for new health-promoting food products.


Subject(s)
Fatty Acids , Lipidomics , Sorghum , Sorghum/chemistry , Sorghum/metabolism , Fatty Acids/chemistry , Fatty Acids/analysis , Fatty Acids/metabolism , Lipids/chemistry , Lipids/analysis , Esters/analysis , Esters/chemistry , Esters/metabolism , Australia , Seeds/chemistry , Seeds/metabolism , Edible Grain/chemistry , Edible Grain/metabolism
9.
ACS Appl Mater Interfaces ; 16(39): 51876-51898, 2024 Oct 02.
Article in English | MEDLINE | ID: mdl-39311719

ABSTRACT

Polyphosphoesters (PPEs) represent an innovative class of biodegradable polymers, with the phosphate ester serving as the core repeating unit of their polymeric backbone. Recently, biomaterials derived from functionalized PPEs have garnered significant interest in biomedical applications because of their commendable biocompatibility, biodegradability, and the capacity for functional modification. This review commences with a brief overview of synthesis methodologies and the distinctive properties of PPEs, including thermoresponsiveness, degradability, stealth effect, and biocompatibility. Subsequently, the review delves into the latest applications of PPEs-based nanocarriers for drug or gene delivery and PPEs-based polymeric prodrugs and scaffolds in the biomedical field, presenting several illustrative examples for each application. By encapsulating the advancements of recent years, this review aims to offer an enhanced understanding and serve as a reference for the synthesis and biomedical applications of functional PPEs.


Subject(s)
Biocompatible Materials , Polymers , Biocompatible Materials/chemistry , Biocompatible Materials/chemical synthesis , Humans , Polymers/chemistry , Polymers/chemical synthesis , Drug Carriers/chemistry , Drug Carriers/chemical synthesis , Animals , Esters/chemistry
10.
Ther Deliv ; 15(10): 769-779, 2024.
Article in English | MEDLINE | ID: mdl-39287201

ABSTRACT

Aim: To achieve colon-targeted release of mefenamic acid from its ester-linked amylose prodrugs.Materials & methods: The prodrug was characterized by 1H NMR and IR spectroscopy. Drug activation and release profile was studied in enzyme enriched simulated physiological media via UV-vis spectroscopy and was validated with HPLC analysis. ELISA assay was employed for evaluating the % inhibition of COX-1 and COX-2 inhibition at different concentrations of the prodrug preincubated with ester and/ or amylose hydrolyzing enzymes. SEM studies further validated the performance of the prodrug under simulated physiological conditions.Results: Pancreatin was essential for the prodrug activation in SIM to make the ester bonds in prodrug vulnerable to hydrolysis by esterase. This evidence was confirmed by drug release studies, HPLC analysis, ELISA assay and SEM investigation where the ester conjugated prodrug showed marked stability in physiological media only to get activated in the presence of amylose degrading enzyme.Conclusion: Ester linked amylose-mefenamic acid conjugate showed both enzyme responsive activation and release in SIM.


[Box: see text].


Subject(s)
Amylose , Anti-Inflammatory Agents, Non-Steroidal , Drug Liberation , Prodrugs , Prodrugs/chemistry , Prodrugs/chemical synthesis , Prodrugs/pharmacology , Amylose/chemistry , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Mefenamic Acid/chemistry , Mefenamic Acid/pharmacology , Esters/chemistry , Humans , Cyclooxygenase 1/metabolism , Cyclooxygenase 1/chemistry , Cyclooxygenase 2/metabolism , Hydrolysis , Drug Stability
11.
Arch Microbiol ; 206(10): 406, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39292269

ABSTRACT

Mayaro virus (MAYV) is the causative agent of Mayaro fever, which is characterized mainly by acute fever and long-term severe arthralgia, common manifestations of other arbovirus infections, making the correct diagnosis a challenge. Besides, MAYV infections have been reported in South America, especially in Brazil. However, the lack of vaccines or specific antiviral drugs to control these infections makes the search for new antivirals an urgent need. Herein, we evaluated the antiviral potential of synthetic ß-enaminoesters derivatives against MAYV replication and their pharmacokinetic and toxicological (ADMET) properties using in vitro and in silico strategies. For this purpose, Vero cells were infected with MAYV at an MOI of 0.1, treated with compounds (50 µM) for 24 h, and virus titers were quantified by plaque reduction assays. Compounds 2b (83.33%) and 2d (77.53%) exhibited the highest activity with inhibition rates of 83.33% and 77.53%, respectively. The most active compounds 2b (EC50 = 18.92 µM; SI > 52.85), and 2d (EC50 = 14.52 µM; SI > 68.87) exhibited higher potency and selectivity than the control drug suramin (EC50 = 38.97 µM; SI > 25.66). Then, we investigated the mechanism of action of the most active compounds. None of the compounds showed virucidal activity, neither inhibited virus adsorption, but compound 2b inhibited virus entry (62.64%). Also, compounds 2b and 2d inhibited some processes involved with the release of new virus particles. Finally, in silico results indicated good ADMET parameters of the most active compounds and reinforced their promising profile as drug candidates against MAYV.


Subject(s)
Alphavirus , Antiviral Agents , Esters , Virus Replication , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Chlorocebus aethiops , Animals , Vero Cells , Esters/pharmacology , Esters/chemistry , Alphavirus/drug effects , Virus Replication/drug effects , Computer Simulation , Brazil , Alphavirus Infections/drug therapy , Alphavirus Infections/virology
12.
ACS Appl Bio Mater ; 7(9): 5784-5794, 2024 Sep 16.
Article in English | MEDLINE | ID: mdl-39226406

ABSTRACT

Hydrated dispersions containing equimolar mixtures of cationic and anionic amphiphiles, referred to as catanionic systems, exhibit synergistic physicochemical properties, and mixing single-chain cationic and anionic lipids can lead to the spontaneous formation of vesicles as well as other phase structures. In the present work, we have characterized two catanionic systems prepared by mixing N-acyltaurines (NATs) and sarcosine alkyl esters (SAEs) bearing 11 and 12 C atoms in the acyl/alkyl chains. Turbidimetric and isothermal titration calorimetric studies revealed that both NATs form equimolar complexes with SAEs having matching acyl/alkyl chains. The three-dimensional structure of the sarcosine lauryl ester (lauryl sarcosinate, LS)-N-lauroyltaurine (NLT) equimolar complex has been determined by single-crystal X-ray diffraction. The LS-NLT equimolar complex is stabilized by electrostatic attraction and multiple hydrogen bonds, including classical, strong N-H···O hydrogen bonds as well as several C-H···O hydrogen bonds between the two amphiphiles. DSC studies showed that both equimolar complexes show single sharp phase transitions. Transmission electron microscopy and dynamic light scattering studies have demonstrated that the LS-NLT catanionic complex assemblies yield stable medium-sized vesicles (diameter 280-350 nm). These liposomes were disrupted at high pH, suggesting that the designed catanionic complexes can be used to develop base-labile drug delivery systems. In vitro studies with these catanionic liposomes showed efficient entrapment (73% loading) and release of the anticancer drug 5-fluorouracil in the physiologically relevant pH range of 6.0-8.0. The release rate was highest at pH 8.0, reaching about 78%, 90%, and 100% drug release at 2, 6, and 12 h, respectively. These observations indicate that LS-NLT catanionic vesicles will be useful for designing drug delivery systems, particularly for targeting organs such as the colon, which are inherently at basic pH.


Subject(s)
Biocompatible Materials , Fluorouracil , Particle Size , Fluorouracil/chemistry , Molecular Structure , Biocompatible Materials/chemistry , Biocompatible Materials/chemical synthesis , Materials Testing , Cations/chemistry , Sarcosine/chemistry , Sarcosine/analogs & derivatives , Esters/chemistry , Humans , Liposomes/chemistry
13.
J Agric Food Chem ; 72(39): 21752-21762, 2024 Oct 02.
Article in English | MEDLINE | ID: mdl-39265547

ABSTRACT

Simultaneous detection of the dynamic distribution of long-chain fatty acid ethyl esters (LCFAEEs) during Baijiu distillation is crucial for optimizing its flavor and health attributes. In this study, we synthesized a simple, cost-effective Fe3O4@NH2 adsorbent to simultaneously extract eight LCFAEEs from Baijiu. Through density functional theory and adsorption experiments, we elucidated 1,6-hexanediamine as a surface modifier, with the -NH2 groups providing adsorption sites for the LCFAEEs via hydrogen-bonding interactions and van der Waals forces. Additionally, we established the magnetic solid-phase extraction-GC-MS extraction technique combined with stable isotope dilution analysis to analyze LCFAEEs. This method revealed the dynamic distribution patterns of LCFAEEs during strong aroma-type Baijiu (SAB) distillation. We observed that the concentrations of the eight LCFAEEs gradually decreased with prolonged distillation and were significantly correlated with ethanol concentration. To ensure optimal flavor and clarity in SAB, it is recommended to select the heart-stage base Baijiu with an alcohol content of 58%-63%.


Subject(s)
Distillation , Esters , Fatty Acids , Flavoring Agents , Gas Chromatography-Mass Spectrometry , Odorants , Esters/chemistry , Distillation/methods , Adsorption , Fatty Acids/chemistry , Odorants/analysis , Flavoring Agents/chemistry , Solid Phase Extraction/methods , Solid Phase Extraction/instrumentation , Magnetite Nanoparticles/chemistry , Alcoholic Beverages/analysis
14.
J Agric Food Chem ; 72(40): 22054-22062, 2024 Oct 09.
Article in English | MEDLINE | ID: mdl-39320050

ABSTRACT

As part of continuous work to explore novel and efficient fungicides originating from natural products, a series of cyclobutyl oxime ester derivatives containing an α,ß-unsaturated carbonyl moiety were designed and synthesized. In line with the primary evaluation of the inhibitory effect on common pathogenic fungi causing crop failure, a systematic study on the antifungal activity of target compounds against Rhizoctonia solani was carried out. Most target compounds exhibited satisfactory antifungal activity, and 10 of them were superior to the positive control trifloxystrobin. The most notable median effective concentration (EC50) of compound 6b was 1.70 µg/mL, which was considerable for an intensive study. The control efficacy of compound 6b on potted rice against R. solani was superior to trifloxystrobin at identical concentration. The mycelial morphology and cell membrane permeability of the treated fungi were disrupted, and the meaningful enzyme activities of SDH and POD were also restrained. The reactive oxygen species, nuclear morphology, and mitochondrial membrane potential of the treated hypha reflected an apparent difference compared with the normal morphology, which represented mitochondrial function damage. In addition, chemical features essential for the activity and docking mode within the compound and cytochrome bc1 complex were accessed by computer-aided technology. This study provided insights into the development of new green and efficient fungicides targeting the mitochondria.


Subject(s)
Fungicides, Industrial , Mitochondria , Oximes , Rhizoctonia , Fungicides, Industrial/pharmacology , Fungicides, Industrial/chemistry , Fungicides, Industrial/chemical synthesis , Rhizoctonia/drug effects , Rhizoctonia/growth & development , Oximes/chemistry , Oximes/pharmacology , Mitochondria/drug effects , Mitochondria/metabolism , Structure-Activity Relationship , Esters/chemistry , Esters/pharmacology , Plant Diseases/microbiology , Fungal Proteins/chemistry , Fungal Proteins/metabolism , Molecular Structure , Molecular Docking Simulation , Reactive Oxygen Species/metabolism , Membrane Potential, Mitochondrial/drug effects , Microbial Sensitivity Tests
15.
J Am Chem Soc ; 146(40): 27267-27273, 2024 Oct 09.
Article in English | MEDLINE | ID: mdl-39331495

ABSTRACT

α-Amino esters are precursors to noncanonical amino acids used in developing small-molecule therapeutics, biologics, and tools in chemical biology. α-C-H amination of abundant and inexpensive carboxylic acid esters through nitrene transfer presents a direct approach to α-amino esters. Methods for nitrene-mediated amination of the protic α-C-H bonds in carboxylic acid esters, however, are underdeveloped. This gap arises because hydrogen atom abstraction (HAA) of protic C-H bonds by electrophilic metal-nitrenoids is slow: metal-nitrenoids preferentially react with polarity-matched, hydridic C-H bonds, even when weaker protic C-H bonds are present. This study describes the discovery and evolution of highly stable protoglobin nitrene transferases that catalyze the enantioselective intermolecular amination of the α-C-H bonds in carboxylic acid esters. We developed a high-throughput assay to evaluate the activity and enantioselectivity of mutant enzymes together with their sequences using the Every Variant Sequencing (evSeq) method. The assay enabled the identification of enantiodivergent enzymes that function at ambient conditions in Escherichia coli whole cells and whose activities can be enhanced by directed evolution for the amination of a range of substrates.


Subject(s)
Biocatalysis , Esters , Esters/chemistry , Esters/metabolism , Amination , Amino Acids/chemistry , Amino Acids/metabolism , Carboxylic Acids/chemistry , Stereoisomerism , Molecular Structure , Imines/chemistry , Imines/metabolism
16.
Org Biomol Chem ; 22(39): 8010-8023, 2024 10 09.
Article in English | MEDLINE | ID: mdl-39257242

ABSTRACT

(2Z)-Lachnophyllum methyl ester and (4Z)-Lachnophyllum lactone were recently identified as major components in essential oils and extracts of Conyza bonariensis from Togo. Extended biological evaluation of these acetylenic compounds was however hampered by the reduced amounts isolated. A synthetic route was designed providing access to larger quantities of these two natural products as well as to original non-natural analogs with the prospect of exploring for the first time the structure-activity relationships in this series. Using LC/MS analysis, synthetic samples allowed confirming the presence of the two previously isolated natural products in plant extracts obtained by the accelerated solvent extraction technique. The nematocidal activity of the synthesized compounds confirmed the potency of the natural products, which remain the most active among all analogs tested. The synthesized compounds were also assessed against Leishmania infantum axenic amastigotes and the Mycobacterium tuberculosis H37Rv pathogenic strain. (2Z)-Lachnophyllum methyl ester, (4Z)-Lachnophyllum lactone and lactone analogs exhibited the strongest antileishmanial potency. As expected, a longer alkyl chain was necessary to observe significant antimycobacterial activity. The lactone analog bearing a C10 lipophilic appendage displayed the highest antimycobacterial potency. The notable activities of lactones, naturally occurring or analogs, either nematicidal, antileishmanial or antimycobacterial, were compared to their cytotoxicity for mammalian cells and revealed moderate selectivity index values. In this regard, the innocuous (2Z)-Lachnophyllum methyl ester and its analogs open up more promising perspectives for the discovery of bioactive agents to protect both agricultural crops and human health.


Subject(s)
Lactones , Lactones/pharmacology , Lactones/chemistry , Lactones/chemical synthesis , Mycobacterium tuberculosis/drug effects , Animals , Biological Products/pharmacology , Biological Products/chemistry , Biological Products/chemical synthesis , Biological Products/isolation & purification , Structure-Activity Relationship , Microbial Sensitivity Tests , Antinematodal Agents/pharmacology , Antinematodal Agents/chemical synthesis , Antinematodal Agents/chemistry , Antinematodal Agents/isolation & purification , Humans , Molecular Structure , Esters/pharmacology , Esters/chemistry , Esters/chemical synthesis
17.
Chem Biol Drug Des ; 104(3): e14631, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39317695

ABSTRACT

To combine the activity characteristics of 18ß-glycyrrhetinic acid (18ß-GA) and anthraquinone compounds (rhein and emodin), reduce toxicity, and explore the structure-activity relationship (SAR) of anthraquinones, 18ß-GA-anthraquinone ester compounds were synthesized by one-step organic synthesis. The products were separated and purified by HPLC and characterized by NMR and EI-MS. It was finally determined as di-18ß-GA-3-rhein ester (1, New), GA dimer (2, known), 18ß-GA-3-emodin ester (3, known), and di-18ß-GA-1-emodin ester (4, new). The MIC of three reactants and four products against Escherichia coli and Staphylococcus aureus were detected in vitro. Its developmental toxicity and cardiotoxicity were assessed using zebrafish embryos. The experimental results showed that rhein had the best antibacterial activity against Staphylococcus aureus with MIC50 of 2.4 mM, and it was speculated that -COOH, -OH, and intramolecular hydrogen bonds in anthraquinone compounds would enhance the antibacterial effect, while the presence of-CH3 might weaken the antibacterial activity. Product 1 increased the hatching rate and survival rate of zebrafish embryos and reduced the malformation rate and cardiomyocyte apoptosis. This experiment lays the foundation for further studying the SAR of anthraquinones and providing new drug candidates.


Subject(s)
Anthraquinones , Anti-Bacterial Agents , Escherichia coli , Glycyrrhetinic Acid , Microbial Sensitivity Tests , Staphylococcus aureus , Zebrafish , Animals , Anthraquinones/pharmacology , Anthraquinones/chemistry , Anthraquinones/chemical synthesis , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Glycyrrhetinic Acid/pharmacology , Glycyrrhetinic Acid/analogs & derivatives , Glycyrrhetinic Acid/chemistry , Glycyrrhetinic Acid/chemical synthesis , Staphylococcus aureus/drug effects , Structure-Activity Relationship , Escherichia coli/drug effects , Embryo, Nonmammalian/drug effects , Esters/chemistry , Esters/pharmacology , Esters/chemical synthesis
18.
J Med Chem ; 67(16): 14329-14344, 2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39091011

ABSTRACT

As an oleanolic acid derivative, CDDO-Me lacks selectivity for tumors. Based on the high reactive oxygen species (ROS) level in cancer cells, compound 4 was selected from 17 new CDDO arylboronate ester derivatives. A preliminary study revealed that 4 displayed the highest selectivity for cancer cells. Furthermore, 4 could be transformed to 4H by ROS to increase its covalent binding ability and antiproliferation effect (IC50 of 2.11 vs 0.37 µM) in BGC-823 cells. Interestingly, 4 increased ROS levels to induce apoptosis in BGC-823 cells. Moreover, the LD50 of 4 (91.2 mg/kg) was much greater than that of CDDO-Me (61.7 mg/kg) in ICR mice. A pharmacokinetic study indicated that 4 could be transformed to 4H in vivo. In addition, 4 exhibited a greater tumor inhibition rate (86.2%) than CDDO-Me (51.7%). Overall, the design of 4 provided an effective modification strategy for CDDO to increase the selectivity for cancer cells.


Subject(s)
Antineoplastic Agents , Apoptosis , Cell Proliferation , Mice, Inbred ICR , Oleanolic Acid , Animals , Humans , Male , Mice , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Apoptosis/drug effects , Boronic Acids/chemistry , Boronic Acids/pharmacology , Cell Line, Tumor , Cell Proliferation/drug effects , Drug Screening Assays, Antitumor , Esters/chemistry , Esters/pharmacology , Esters/chemical synthesis , Molecular Structure , Oleanolic Acid/analogs & derivatives , Oleanolic Acid/chemistry , Oleanolic Acid/pharmacology , Oleanolic Acid/pharmacokinetics , Oleanolic Acid/chemical synthesis , Reactive Oxygen Species/metabolism , Structure-Activity Relationship , Formamides/chemistry , Formamides/pharmacology , Ethylamines/chemistry , Ethylamines/pharmacology
19.
Int J Biol Macromol ; 277(Pt 3): 134286, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39217036

ABSTRACT

As the derivative of konjac glucomannan (KGM), carboxymethyl konjac glucomannan (CMK) has attracted increasing attention in the polysaccharide hydrogel fields with the aim of improving the performance related to drug delivery and release. In this study, we prepared a CMK-based hydrogel with dual characteristic crosslinks, and unlocked new applications of this type of hydrogel in soft sensor fields. CMK and poly (vinyl alcohol) were used as substrates, and physical crosslinks were constructed via the freeze-thawing treatments and covalent crosslinks were built via the boronic ester bonding. As-prepared hydrogel possessed significantly improved mechanical performance because the boronic ester bonding, on the one hand, well associated the two kinds of polymer chains, and on the other hand, played the role of 'sacrificial crosslinks'. Furthermore, the occurrence of dynamic boronic ester bonding gave the hydrogel strain- and temperature-sensitive ionic conductivity, and therefore, the hydrogels could be used to identify human motions and as-resulted environmental temperature alterations, and worked well in various scenarios. This work activates new application of CMK in the multimodal sensing field, and also proposes an intriguing way of building multiple crosslinks in the KGM derivative-based hydrogels.


Subject(s)
Boronic Acids , Hydrogels , Mannans , Mannans/chemistry , Hydrogels/chemistry , Boronic Acids/chemistry , Esters/chemistry , Humans , Polyvinyl Alcohol/chemistry , Temperature , Cross-Linking Reagents/chemistry
20.
J Agric Food Chem ; 72(36): 19883-19890, 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39214666

ABSTRACT

Elevation of the plasma levels of (S)-lactate (Lac) and/or (R)-beta-hydroxybutyrate (BHB) occurs naturally in response to strenuous exercise and prolonged fasting, respectively, resulting in millimolar concentrations of these two metabolites. It is increasingly appreciated that Lac and BHB have wide-ranging beneficial physiological effects, suggesting that novel nutritional solutions, compatible with high-level and/or sustained consumption, which allow direct control of plasma levels of Lac and BHB, are of strong interest. In this study, we present a molecular hybrid between (S)-lactate and the BHB-precursor (R)-1,3-butanediol in the form of a simple ester referred to as LaKe. We show that LaKe can be readily prepared on the kilogram scale and undergoes rapid hydrolytic conversion under a variety of physiological conditions to release its two constituents. Oral ingestion of LaKe, in rats, resulted in dose-dependent elevation of plasma levels of Lac and BHB triggering expected physiological responses such as reduced lipolysis and elevation of the appetite-suppressing compound N-L-lactoyl-phenylalanine (Lac-Phe).


Subject(s)
3-Hydroxybutyric Acid , Lactic Acid , Animals , Rats , 3-Hydroxybutyric Acid/blood , 3-Hydroxybutyric Acid/chemistry , Male , Lactic Acid/blood , Esters/chemistry , Esters/metabolism , Rats, Sprague-Dawley , Butylene Glycols/chemistry , Butylene Glycols/metabolism
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