Search Results (67)

This study evaluated whether the volatile profile of methyl linoleate (MLO) can predict its pro-inflammatory capacity. MLO was subjected to two oxidation conditions simulating ambient storage and high-temperature frying. Free radicals, volatile compounds, and aldehydes were quantified using ESR, HS-SPME-GC-MS, and UPLC-MS/MS. Oxidized MLO was applied to RAW264.7 macrophages to evaluate inflammatory cytokines and oxidative stress responses, and PLSR models were developed to predict cellular outcomes based on volatile fingerprints. Both oxidation conditions induced substantial increases in short-chain and unsaturated aldehydes, with high-temperature oxidation generating markedly higher levels of key volatiles. Oxidized MLO significantly elevated TNF-α, IL-1β, COX-2, ROS, NO, and MDA while reducing SOD activity (p < 0.05), demonstrating strong pro-inflammatory and pro-oxidant effects. Volatile-based PLSR models achieved high predictive performance, with cross-validated and external R² values approaching 0.9 and RPD values exceeding 2. These findings show that volatile oxidation products reliably reflect the pro-inflammatory potency of oxidized lipids and can support the ranking of oxidized oils and lipid-rich foods, as well as guide processing and dietary strategies. Full article

Stink bugs (Hemiptera: Pentatomidae and Scutelleridae) produce a wide range of semiochemical compounds that function as pheromones, allomones, synomones, and kairomones. This study aimed to isolate, identify, and synthesize the main semiochemical components of the metathoracic glands of Aelia rostrata, A. melanota, Eurygaster integriceps, and E. maura. Extracts from male and female glands were analyzed using GC–MS, which revealed that (E)-2-hexen-1-ol acetate was the dominant compound in all four species. In addition, several α,β-unsaturated aldehydes with chain lengths of C6–C8, including (E)-2-hexenal, (E)-2-heptenal, (E)-2-octenal, and (E)-2-hexen-1-ol, were detected. These compounds are characterized by strong odors and irritant properties, acting as defensive allomones and alarm pheromones. Synthetic routes were developed for these key compounds. In particular, (E)-2-hexen-1-ol acetate was efficiently synthesized via acetylation of (E)-2-hexen-1-ol using acetic anhydride in the presence of 4-dimethylaminopyridine (DMAP) as a catalyst. This approach significantly reduced the reaction time to 30 min and improved the yield to 90%. Although DMAP is widely used in organic synthesis, the simplicity and efficiency of this optimized protocol for producing semiochemical analogues of stink bugs have not been previously reported. Preliminary trials with synthetic lures indicated their potential for pheromone-based monitoring of stink bug populations in cereal fields. The optimized semiochemical blends developed in this study are expected to contribute to integrated pest management strategies by enabling more effective detection and control of these economically important pests. Full article

The selective hydrogenation of the C=O bond over the C=C bond in α,β-unsaturated aldehydes remains a well-known challenge. This work investigates the liquid-phase catalytic transfer hydrogenation of crotonaldehyde to crotyl alcohol over ReOx-based catalysts, using formic acid (FA) as an in situ hydrogen donor. A series of 10 wt% Re catalysts supported on G200, g-C₃N₄, TiO₂, and ZrO₂ were synthesized and tested in a batch reactor at 20 bar and temperatures of 140–180 °C. Catalysts were characterized by XRD, BET, NH₃-TPD, and XPS to correlate their physicochemical properties with catalytic behavior. Among the studied materials, ReO_x/ZrO₂ and ReO_x/g-C₃N₄ exhibited the highest crotyl alcohol selectivity above 57% for all reaction temperatures, evaluated at crotonaldehyde conversion of 25%. The nature of the support strongly influenced the dispersion and oxidation state of Re species, as well as the surface acidity, which governed the activation of both the carbonyl group and the FA decomposition. Compared with molecular hydrogen, FA improved both conversion and selectivity due to its superior hydrogen-donating ability in the aqueous phase. These findings demonstrate that tailoring the acid–base characteristics of ReO_x catalysts and employing biomass-derived hydrogen donors represent an effective strategy for selective hydrogenation of α,β-unsaturated aldehydes. Full article

Human DNA is continuously exposed to endogenous and exogenous agents that generate over 100,000 lesions per cell each day. In addition to damage to nucleobases, deoxyribose, and phosphate groups, a particularly harmful class of lesions involves non-canonical DNA termini—structures deviating from the canonical 3′-hydroxyl and 5′-phosphate ends. These aberrant DNA ends can obstruct essential DNA transactions and, if left unrepaired, contribute to cytotoxicity and mutagenesis. Their biological significance is further highlighted by the severe pathologies linked to deficiencies in DNA end-processing enzymes, including inflammation, cancer predisposition syndromes, neurodegeneration, and aging. This review highlights recent advances in our understanding of the formation, prevalence, and repair mechanisms of several key non-canonical DNA end structures, including 3′-phosphate, 3′-phosphoglycolate, 3′-α,β-unsaturated aldehyde and its glutathione derivative, 5′-deoxyribose-5-phosphate, 2′-deoxyribonucleoside-5′-aldehyde, and 5′-adenosine monophosphate. These non-canonical DNA terminal structures arise from various sources, such as radical-induced oxidation of the 2-deoxyribose moiety and DNA repair pathways. While this review does not cover the full spectrum of non-canonical termini, the selected structures are emphasized based on quantitative data supporting their biological relevance. The review also discusses their broader implications in mitochondrial DNA maintenance and inflammatory signaling and highlights key knowledge gaps that warrant further investigation. Full article

An efficient and practical procedure for the synthesis of (E)-α,β-unsaturated amides incorporating α-aminophosphonates, derived from readily accessible phosphonoacetamides, via the Horner–Wadsworth–Emmons (HWE) reaction was developed. The influence of reaction parameters, including base, solvent, and temperature, as well as the scope of the method with different aldehydes, was examined, affording the target compounds in good yields and with high (E)-selectivity. The required phosphonoacetamides were conveniently prepared through a Kabachnik–Fields reaction of aldehydes, benzylamine and dimethyl phosphite followed by hydrogenolytic cleavage of the N-Bn bond, acylation with bromoacetyl bromide, and a subsequent Arbuzov reaction. This HWE protocol provides straightforward access to a broad range of (E)-α,β-unsaturated amides incorporating α-aminophosphonates under mild conditions, offering valuable scaffolds with potential pharmacological relevance as anticancer agents. Full article

While omega-6 fatty acids play an important role in normal cell function, their excess in the diet is associated with an increased risk of developing diseases such as obesity, non-alcoholic fatty liver disease (NAFLD), inflammatory bowel disease (IBD) and Alzheimer’s disease. Furthermore, excessive intake has been shown to lead to chronic inflammation, which is related to increased production of reactive oxygen species (ROS). This conditioncan initiate lipid peroxidation in cell membranes, leading to the degradation of their fatty acids. One of the main products of omega-6 peroxidation is the α,β-unsaturated aldehyde, i.e., 4-hydroxynonenal (4-HNE), which is able to form four diastereoisomeric adducts with guanine. These 4-HNE adducts have been identified in the DNA of humans and rodents. Depending on their stereochemistry, they are able to influence double helix stability and cause DNA–DNA or DNA–Protein cross-links. Moreover, studies have shown that 4-HNE adducts formed in the human genome are considered mutation hotspots in hepatocellular carcinoma. Although the cell possesses defence mechanisms, without a well-balanced diet allowing correct cell function, they may not be sufficient to protect the genetic code. This review provides an overview of the molecular mechanisms underlying oxidative stress, lipid peroxidation, and the formation of DNA adducts. Particular emphasis is placed on the role of an omega-6-rich diet in inflammatory diseases, and on the formation of 4-HNE, which is a major product of lipid peroxidation, and its broader implications for genome stability, ageing, and disease progression. Full article

In recent years, Co-based catalysts have attracted considerable attention in research on selective hydrogenation reactions because of their mild activities and favorable selectivities for producing intermediate products, especially in the selective hydrogenation of α,β-unsaturated aldehydes (UAL). However, the low activity of Co-based catalysts for activating hydrogen limits their application in industry, and the diversity of forms and electronic states of Co-based catalysts also leads to the development of complex products and hydrogenation mechanisms at Co active sites. This review provides a comprehensive and systematic overview of recent progress in the selective hydrogenation of UAL over Co-based catalysts, where the preparation methods, hydrogenation properties, and UAL hydrogenation mechanisms of Co-based catalysts are carefully discussed. The influences of nanosize effects, electronic effects, and coordination effects on Co metal and Co oxides are investigated. In addition, the different reaction mechanisms at Co active sites are compared, and their strengths and weaknesses for C=O hydrogenation are further proposed. Finally, the outlook and challenges for the future development of Co-based hydrogenation catalysts are highlighted. Full article

The availability of water-soluble nanoparticles allows catalytic reactions to occur in highly desirable green environments. The catalytic activity and selectivity of water-soluble palladium nanoparticles capped with 6-(carboxylate)hexanethiolate (C6-PdNP) and 5-(trimethylammonio)pentanethiolate (C5-PdNP) were investigated for the reduction of 4-nitrophenol, the oxidation of α,β-conjugated aldehydes, and the C-C coupling of phenylboronic acid. The study showed that between the two PdNPs, C6-PdNP exhibits better catalytic activity for the reduction of 4-nitrophenol to 4-aminophenol in the presence of sodium borohydride and the selective oxidation of conjugated aldehydes to conjugated carboxylic acids. For the latter reaction, molecular hydrogen (H₂) and H₂O act as oxidants for the surface palladium atoms on PdNPs and conjugated aldehyde substrates, respectively. The results indicated that the competing addition activities of Pd-H and H₂O toward the π-bond of different unsaturated substrates promote either reduction or oxidation reactions under mild conditions in organic solvent-free environments. In comparison, C5-PdNP exhibited higher catalytic activity for the C-C coupling of phenylboronic acid. Gas chromatography–mass spectrometry (GC-MS) was mainly used as an analytical technique to examine the products of catalytic reactions. Full article

Edible oils are essential dietary components that provide crucial micronutrients. However, their quality can deteriorate during frying—a common cooking method—and with prolonged light exposure due to chemical reactions such as hydrolysis, oxidation, and polymerization. These processes lead to the formation of harmful compounds, particularly aldehydes. This study investigates how thermal and light exposure impact the chemical composition of five widely used edible oils: olive, rapeseed, sunflower, sesame, and peanut oils. For the thermal treatment, the oils were heated to 190 ± 5 °C in a commercial fryer, with samples taken at the start and after 10 min and 60 min of heating, while intermittently frying chicken nuggets to simulate typical frying conditions. For the light exposure treatment, the oil samples were exposed to direct sunlight for 3 and 8 h, with control samples being collected beforehand. The oil composition was analyzed using an advanced 800 MHz nuclear magnetic resonance (NMR) instrument with a triple-resonance inverse cryoprobe, providing high sensitivity and resolution. The results revealed a significant increase in various aldehyde compounds in all oils under both thermal and light exposure conditions. Notably, this study identified the generation of genotoxic and cytotoxic α,β-unsaturated aldehydes, including 4-hydroperoxy-(E)-2-alkenals, 4-hydroxy-(E)-2-alkenals, and 4,5-epoxy-(E)-2-alkenals. Given the established association of aldehydes with health risks, including cancer, Alzheimer’s, and Parkinson’s diseases, these findings highlight the importance of monitoring oil degradation during cooking and the appropriate storage of oils to minimize light exposure to reduce potential health risks. Full article

The present article describes the successful performance of crossed aldol reactions of the CF₃-containing pseudo-C₂ symmetric cyclic imide with various aldehydes. The utilization of HMPA as an additive attained the preferential formation of the anti-products in good to excellent yields, which contrasts with our previous method without this additive, proceeding to furnish the corresponding syn-isomers. The effective participation of ketones and α,β-unsaturated carbonyl compounds in reactions with this imide was also demonstrated to expand the application of this imide. Full article

A novel and controllable synthesis of thioacetals/thioketals and β-sulfanyl ketones mediated by the reaction of aldehyde/acetone with thiols has been developed. In this protocol, β-sulfanyl ketones can be generated without the prior preparation of α, β-unsaturated carbonyl compounds. A variety of thiols reacted with aldehyde/acetone and provided the corresponding thioacetals/thioketals and β-sulfanyl ketones in good to excellent yields, respectively. This protocol is operationally simple, mild, and atom-economical, providing controllable access to thioacetals/thioketals and thia-Michael addition products under mild conditions. Full article

Podophyllotoxin, a cyclolignan natural product, has been the object of extensive chemomodulation to obtain better chemotherapeutic agents. Among the obtained podophyllotoxin derivatives, podophyllic aldehyde showed very interesting potency and selectivity against several tumoral cell lines, so it became our lead compound for further modifications, as described in this work, oriented toward the enlargement of the cyclolignan skeleton. Thus, modifications performed at the aldehyde function included nucleophilic addition reactions and the incorporation of the aldehyde carbon into several five-membered rings, such as thiazolidinones and benzo-fused azoles. The synthesized derivatives were evaluated against several types of cancer cells, and although some compounds were cytotoxic at the nanomolar range, most of them were less potent and less selective than the parent compound podophyllic aldehyde, with the most potent being those having the lactone ring of podophyllotoxin. In silico ADME evaluation predicted good druggability for most of them. The results indicate that the γ-lactone ring is important for potency, while the α,β-unsaturated aldehyde is necessary to induce selectivity in these cyclolignans. Full article

Heterocyclic derivatives of hormones have attracted great interest as a privileged scaffold for drug discovery due to their outstanding biological activity. A number of them are potent anticancer agents which are used in the chemotherapy of breast and prostate cancers. Here, the data obtained by the authors in the field of studying functionalized thiohydrazides as simple “versatile agents” for the installation of heterocyclic moiety to the steroid core are summarized. Namely, a flexible synthetic approach to unknown pyrazolines, 1,3,4-thiadiazole, thiadiazine, and pyridazine derivatives of steroids with selective control of heterocyclization patterns are discussed. Steroidal 1,3,4-thiadiazoles were obtained via the oxidative heterocyclization of oxamic acid thiohydrazides with 16-hydroxymethylidene-∆^1,3,5(10)-estratrieno-17-one. An extension of this reaction to steroidal α,β-unsaturated ketones resulted in androst-5-ene-[17,16d]-pyrazolines. Spiro-androstene-17,6′[1′,3′,4′]thiadiazines were exclusively synthesized employing 16β,17β-epoxypregnenolone. Using 21-bromopregna-5,16-dien-20-one as a substrate, 17-[1′,3′,4′]thiadiazine-substituted androstenes were prepared. 18-Nor-5α-androsta-2,13-diene[3,2-d]pyridazines, androsta-2-ene[3,2-d]pyridazines and ∆^1,3,5(10)-estratrieno[16,17-d]pyridazines were synthesized via two steps involving the Vilsmeier–Haack reaction of enolizable steroidal ketones, giving chlorovinyl aldehydes, followed by the imination of the former with oxamic acid thiohydrazides. The antiproliferative activity of the synthesized compounds against breast and prostate cancer cell lines, along with lead compounds’ in-depth characterization, are included. The lead compounds were found to have potent selectivity and, in some cases, a significant effect on the signaling pathways in parental and 4-hydroxytamoxifen-resistant cells. Full article

The synthesis of novel, highly functionalized 5-hydroxy 3-pyrrolin-2-ones via a two-step procedure involving an addition reaction between KCN and corresponding chalcones, followed by ring condensation of the obtained β-cyano ketones with het(aryl)aldehydes under basic conditions is described. This protocol enables the preparation of various 3,5-di-aryl/heteroaryl-4-benzyl substituted α,β-unsaturated γ-hydroxy butyrolactams, which are subjects of significant interest to synthetic organic and medicinal chemistry. Full article

Protein carbonylation is an irreversible form of post-translational modification triggered by reactive oxygen species in animal and plant cells. It occurs either through the metal-catalyzed oxidation of Lys, Arg, Pro, and Thr side chains or the addition of α, β-unsaturated aldehydes and ketones to the side chains of Cys, Lys, and His. Recent genetic studies concerning plants pointed to an implication of protein carbonylation in gene regulation through phytohormones. However, for protein carbonylation to stand out as a signal transduction mechanism, such as phosphorylation and ubiquitination, it must be controlled in time and space by a still unknown trigger. In this study, we tested the hypothesis that the profile and extent of protein carbonylation are influenced by iron homeostasis in vivo. For this, we compared the profile and the contents of the carbonylated proteins in the Arabidopsis thaliana wild-type and mutant-deficient in three ferritin genes under normal and stress conditions. Additionally, we examined the proteins specifically carbonylated in wild-type seedlings exposed to iron-deficient conditions. Our results indicated that proteins were differentially carbonylated between the wild type and the triple ferritin mutant Fer1-3-4 in the leaves, stems, and flowers under normal growth conditions. The profile of the carbonylated proteins was also different between the wild type and the ferritin triple mutant exposed to heat stress, thus pointing to the influence of iron on the carbonylation of proteins. Consistent with this, the exposure of the seedlings to iron deficiency and iron excess greatly influenced the carbonylation of certain proteins involved in intracellular signal transduction, translation, and iron deficiency response. Overall, the study underlined the importance of iron homeostasis in the occurrence of protein carbonylation in vivo. Full article