Search Results (124)

The valence-shell electronic state spectroscopy of β-butyrolactone (CH₃CHCH₂CO₂) is comprehensively investigated by employing experimental and theoretical methods. We report a novel vacuum ultraviolet (VUV) absorption spectrum in the photon wavelength range from 115 to 320 nm (3.9–10.8 eV), together with ab initio quantum chemical calculations at the time-dependent density functional (TD-DFT) level of theory. The dominant electronic excitations are assigned to mixed valence-Rydberg and Rydberg transitions. The fine structure in the CH₃CHCH₂CO₂ photoabsorption spectrum has been assigned to C=O stretching, $v_7^{\prime }\left(a\right)$, CH₂ wagging, $v_{14}^{\prime }\left(a\right)$, C–O stretching, $v_{22}^{\prime }\left(a\right)$, and C=O bending, $v_{26}^{\prime }\left(a\right)$ modes. Photolysis lifetimes in the Earth’s atmosphere from 0 km up to 50 km altitude have been estimated, showing to be a non-relevant sink mechanism compared to reactions with the ^•OH radical. The nuclear dynamics along the C=O and C–C–C coordinates have been investigated at the TD-DFT level of theory, where, upon electronic excitation, the potential energy curves show important carbonyl bond breaking and ring opening, respectively. Within such an intricate molecular landscape, the higher-lying excited electronic states may keep their original Rydberg character or may undergo Rydberg-to-valence conversion, with vibronic coupling as an important mechanism contributing to the spectrum. Full article

The development of antimicrobial resistance drives the search for molecules capable of inhibiting bacterial virulence. Fungi of the Basidiomycota phylum constitute an important source of compounds with antimicrobial activity. The present paper describes a new species named Fulvifomes mexicanus sp. nov. based on morphological and phylogenetic analyses. The methanolic extract of basidiome of this fungus inhibited the motility of Pseudomonas aeruginosa ATCC 9027 and the production of violacein by Chromobacterium violaceum CV026. The metabolomic study of the extract by liquid chromatography–high-resolution electrospray ionization mass spectrometry (LC-HRESIMS) and molecular networking analyses revealed the presence of a complex composition of metabolites including hispidin derivatives, terpenoids, phenols, furanones, alkylglycerols, pyrones, and γ-butyrolactones, among others. Overall, this work represents the first chemical and biological study of a new species of Fulvifomes mexicanus as a source of antipathogenic metabolites for the development of novel antimicrobial agents. Full article

A library of neoisopulegol-based amino and thiol adducts was developed from (+)-neoisopulegol, derived from commercially available (−)-isopulegol. Michael addition of different nucleophiles towards its highly active α,β-unsaturated γ-lactone motif was accomplished, resulting in diverse amino and thiol analogs in stereoselective reactions. Then, the lactone ring was opened, with NH₃ and benzylamine furnishing primary amide and N-benzyl-substituted amide derivatives, respectively. The in vitro antimicrobial effect of prepared compounds was also explored. The results revealed that naphthylmethyl-substituted β-aminolactone, the most promising compound, displayed selective inhibition for the Gram-positive bacteria S. aureus with an MIC (minimum inhibitory concentration) value of 12.5 μM. A docking study was performed to interpret the obtained results. Full article

Background: “Chemsex” involves the intake of a range of drugs (e.g., synthetic cathinones, gamma-hydroxybutyric acid/gamma-butyrolactone (GHB/GBL), ketamine, methamphetamine, “poppers”, type V phosphodiesterase (PDE) inhibitors, MDMA/ecstasy, cocaine, cannabis, and occasionally a few other molecules as well, to enhance and prolong sexual experiences. This paper aims to provide an overview of the clinical pharmacology of the vast range of drugs that are being used for chemsex with a focus on both the medical and psychopathological disturbances that they can produce. Methods: A narrative literature review was conducted using Pubmed, Scopus, and Web of Science databases. A total of 273 papers published up to January 2025 were screened; articles were selected based on relevance to chemsex/sexualized used behaviour and related substances. Both human and preclinical studies were considered. Results: The use of stimulants is likely related to the need to increase as much as possible both sexual arousal and performance but also to increase social interactions. Furthermore, the empathogenic/entactogenic activities of some MDMA-like “love drugs” facilitate the occurrence of “feeling closer/more intimate” emotional sensations, and GHB/GBL may provide the user with a subjective sensation of disinhibition, hence facilitating condomless meetings with a higher number of random partners. Conversely, ketamine may be used to both enjoy its psychotropic dissociative characteristics and facilitate the potentially painful receptive anal intercourse and/or fisting experiences. Most typically, these drugs are consumed in combination, with polydrug exposure possibly facilitating the occurrence of serotonergic syndrome, seizures, drug–drug pharmacokinetics’ interaction, and sympathomimetic overstimulation. Following these polydrug exposures, a range of psychopathological conditions have at times been reported. These issues may lead to misuse of opiates/opioids, gabapentinoids, and/or antipsychotics. Conclusions: Further actions should aim at reducing the stigma that prevents individuals from accessing necessary healthcare and support services. A multidisciplinary approach that combines medical, psychological, and social support remains key to managing the complex challenges posed by chemsex-related drug use. Full article

Background: Chemsex is a subtype of sexualized drug use which is increasingly more prevalent amongst gay, bisexual, and other men who have sex with men (MSM). This use of psychoactive substances in sexual contexts poses an emerging public health concern, since it has been associated with an array of health risks, including mental health risks. Objective: As Chemsex appears to be increasing in the UK, this study aimed to explore Chemsex patterns and mental health amongst Chemsex users in the UK. Methods: Chemsex/drug use patterns and the prevalence of coexisting depression and anxiety, based on the Hospital Anxiety and Depression Scale (HADS), were assessed in an MSM sample via an anonymous online survey between December 2023 and February 2024. Results: A total of 141 UK adults participated in the survey (age range: 26–41 years). High overall use of the three common Chemsex-related substances was reported, including γ-hydroxybutyrate/γ-butyrolactone (GHB/GBL) (77.3%), synthetic cathinones (64.5%), and methamphetamine (47.5%). Injecting (“slamming”) was less prevalent (17.0%), although this practice was the most common amongst weekly Chemsex users (54.2%). Based on provided HADS responses, a high incidence of anxiety (49.9%) was reported among the study population, with the highest (abnormal) anxiety scores observed among weekly Chemsex users (44.4%). The incidence of depression was lower overall (27.0%), whilst the highest (abnormal) scores were also observed in weekly Chemsex users (61.5%). Conclusions: As relevant UK data remain limited, this study offers novel insight into Chemsex patterns and mental health challenges among MSM in the UK, suggesting unmet needs for targeted interventions on mental health issues among this population. Further large-scale and prospective studies are necessary to explore the nuanced interplay between the frequency of Chemsex use and its impact on mental health. Full article

A ferrocenium-catalyzed synthesis of trisubstituted tetrahydrofurans by dehydrative cyclization of diols is reported. Treatment of γ-phenyl-γ-butyrolactone or valerolactone with 2–3 equivalents of MeLi, n-BuLi, or PhLi yielded the corresponding substituted 1,4-butanediols in 41–86% yields. Subsequent dehydrative cyclization of the diols under non-inert conditions using catalytic ferrocenium tetrafluoroborate (10 mol%) produced trisubstituted tetrahydrofurans in 72–83% yields after 48–72 h at 45–70 °C in CH₂Cl₂. This study demonstrates ferrocenium-catalyzed dehydrative cyclization for the first time, offering a convenient route to substituted tetrahydrofurans in two steps from commercial or easily accessible starting materials. Full article

Heat stress poses a significant challenge to animal husbandry, contributing to oxidative stress, intestinal mucosal injury, and apoptosis, which severely impact animal health, growth, and production efficiency. The development of safe, sustainable, and naturally derived solutions to mitigate these effects is critical for advancing sustainable agricultural practices. Butyrolactone-I (BTL-I), a bioactive compound derived from deep-sea fungi (Aspergillus), shows promise as a functional feed additive to combat heat stress in animals. This study explored the protective effects of BTL-I against heat-stress-induced oxidative stress and apoptosis in IPEC-J2 cells and mice. Our findings demonstrated that BTL-I effectively inhibited the heat-stress-induced upregulation of HSP70 and HSP90, alleviating intestinal heat stress. Both in vitro and in vivo experiments revealed that heat stress increased intestinal cell apoptosis, with a significant upregulation of Bax/Bcl-2 expression, while BTL-I pretreatment significantly reduced apoptosis-related protein levels, showcasing its protective effects. Furthermore, BTL-I suppressed oxidative stress markers (ROS and MDA) while enhancing antioxidant activity (SOD levels). BTL-I also reduced the expression of p-PERK, p-eIF2α, ATF4, and CHOP, mitigating oxidative and endoplasmic reticulum stress in intestinal cells. In conclusion, BTL-I demonstrates the potential to improve animal resilience to heat stress, supporting sustainable livestock production systems. Its application as a natural, eco-friendly feed additive will contribute to the development of sustainable agricultural practices. Full article

Infantile spasms are common in Down Syndrome (DS), but the mechanisms by which DS predisposes to this devastating epilepsy syndrome are unclear. In general, neuronal excitability and therefore seizure predisposition results from an imbalance of excitation over inhibition in neurons and neural networks of the brain. Animal models provide clues to mechanisms and thereby provide potential therapeutic approaches. Ts65Dn mice have been the most widely used animal model of DS. In this model, there is evidence for both abnormal cerebral excitation and inhibition: infantile spasms-like clinical and electrographic activity can be elicited by the administration of gamma-aminobutyric acid (GABA)-B receptor agonist, gamma-butyrolactone (GBL), and depolarizing GABA-A responses persist beyond the age of their usual switch to hyperpolarized responses. But despite its widespread use, the Ts65Dn model may be suboptimal because of the absence of numerous genes that are triplicated in human DS and the presence of numerous genes that are not triplicated in human DS. Recently, a transchromosomic mouse artificial chromosome 21 (TcMAC21) mouse model has been developed, which carries a copy of human chromosome 21 and therefore has a genetic composition more similar to human DS. As in Ts65Dn mice, exposure of TcMAC21 mice to GBL results in epileptic spasms, and aberrant excitation has also been demonstrated. This review summarizes excitatory and inhibitory dysfunction in models of DS that may play a role in the generation of seizures and infantile spasms, providing a perspective on past studies and a prelude for future ones. Further elucidation will hopefully lead to rational therapeutic options for DS children with infantile spasms. Full article

Southern Shaanxi is one of China’s high-quality congou black tea production areas. However, the differences in geography, cultivation, and management techniques and production processes lead to uneven qualities of southern Shaanxi congou black tea in different production areas. This study used sensory analysis combined with gas chromatography–ion mobility spectrometry (GC-IMS) to determine southern Shaanxi congou black teas’ geographical origin and volatile fingerprints to prevent economic losses caused by fraudulent labeling. A total of 61 volatile compounds were identified and quantified by GC-IMS. Three main aroma types were found by sensory analysis coupled with significant difference analysis, and a clear correlation between volatile compounds, aroma type, and geographical origin was found by sensory and gallery plot analysis. The black tea with a green/grassy-roast aroma type was mainly distributed in production areas with an altitude of 400–800 m and 1-pentanol, cyclohexanone, 1-penten-3-one, 2-heptanone, dihydroactinidiolide and butyrolactone were the key aroma markers. The black teas produced in production areas with an altitude of 800–1000 m mainly presented strong honey and caramel-like aromas, and sotolone, furaneol, and phenylacetaldehyde played an important role. These results will be helpful for discriminating black tea from different tea production areas in southern Shaanxi. Full article

The aim of this study is to isolate and identify the secondary metabolites of the aerial part of the plant Centaurea bruguieriana (DC.) Hand. -Mazz. subsp. belangeriana (DC.) Bornm. (Centaurea phyllocephala) (Asteraceae), and to study the biological activities of the extracts and isolated compounds with in vitro tests. With the use of chromatography and spectroscopy we identified three elemanolides: 8α-O-(3,4-dihydroxy-2-methylenebutanoyloxy) dehydromelitensine (1), 8α-O-(3-hydroxy-4-acetoxy-2-methylene-butanoyloxy) dehydromelitensine (2) and methyl 6α,8α,15-trihydroxyelema-1,3,11(13)-trien-12-oate (3); two germacranolides: cnicin (4) and 4′-O-acetylcnicin (5); one eudesmanolide: malacitanolide (6); five flavonoids: cirsilineol (7), eupatorine (8), 5-hydroxy, 6,7,3′,4′-tetramethoxy-flavone (9), 3,4′,5,7-tetrahydroxy-6-methoxyflavone 3-O-β-D-glucopyranoside (10) and astragalin (11); and also p-OH-benzoic acid (12) and 3-hydroxy-2-methyl-butyrolactone (13). All the isolated compounds were evaluated in silico with the use of molinspiration, while the crude extract, the organic phase B and compounds 2, 4, 5 and 6 were tested as antioxidants and anti-inflammatories for the inhibition of lipid hyperoxide and the inhibition of lipoxygenase. Full article

A new aluminum complex (NSO)AlMe₂ featuring a hydrogen bond donor on the ligand backbone has been synthesized via the reaction of AlMe₃ with 1-((2-(isopropylamino)phenyl)thio)propan-2-ol (NSO-H) and spectroscopically characterized. In the complex, the aluminum atom is in a distorted tetrahedral coordination sphere determined by the anionic oxygen and neutral nitrogen atoms of the ligand and by the two carbon atoms of the alkyl groups. After proper activation, the complex (NSO)AlMe₂ was able to promote the ring-opening polymerization of L-, rac-lactide, ε-caprolactone and rac-β-butyrolactone. The polymerization of rac-lactide was faster than that of L-lactide: in a toluene solution at 80 °C, the high monomer conversion of 100 equivalents was achieved in 1.5 h, reaching a turnover frequency of 63 mol_LA·mol_Al^–1·h^–1. The experimental molecular weights of the obtained polymers were close to those calculated, assuming the growth of one polymer chain for one added alcohol equivalent and the polydispersity indexes were monomodal and narrow. The kinetic investigation of the polymerization led to the determination of the apparent propagation constants and the Gibbs free energies of activation for the reaction; the terminal groups of the polymers were also identified. The complex (NSO)AlMe₂ was active in harsh conditions such as at a very low concentration or in the melt using technical-grade rac-lactide. A relatively high level of activity was observed in the ring-opening polymerization of ε-caprolactone and rac-β-butyrolactone. DFT calculations were performed and revealed the central role of the NH function of the coordinated ligand. Acting as a hydrogen bond donor, it docks the monomer in the proximity of the metal center and activates it toward the nucleophilic attack of the growing polymer chain. Full article

Background/Objectives: Phyllanthus species are renowned in traditional medicine for their diverse therapeutic properties, including potential anticancer activities. This study explored the antiproliferative potential of six Phyllanthus species by integrating chemical composition with bioactivity assays to identify key antiproliferative compounds. Methods: The integration of liquid chromatography–mass spectrometry (LC-MS)-based chemical composition data with antiproliferative activity against three cancer cell lines—PC-3 (prostate adenocarcinoma), SiHa (cervical carcinoma), and A549 (lung carcinoma)—as well as a normal mouse fibroblast line (L929) was performed by covariate analysis. These compounds were subsequently isolated and structurally characterized using spectroscopic methods. Results: Through covariate statistics, seven m/z features were found to be plausible active compounds, and after isolation, they were related to butyrolactone and arylnaphthalide lignans. Among the active isolates, an unreported compound, (+)-phyllanlathyrin 6, was discovered in the aerial part of Phyllanthus lathyroides. The isolated compounds exhibited moderate to good antiproliferative activity (IC₅₀ < 20 µM) with selectivity to SiHa, validating the covariate-based identification approach. Conclusions: These findings highlight the potential of Phyllanthus species as sources of novel anticancer agents, with specific arylnaphthalide lignans showing promising cytotoxic effects that could be further developed into therapeutic leads. Additionally, this study underscores the value of combining advanced analytical techniques with bioactivity testing to uncover bioactive compounds from natural sources. The results contribute to the growing body of evidence supporting the therapeutic relevance of Phyllanthus species and provide a foundation for future drug development efforts targeting cancer treatment. Full article

Garcinia gummi-gutta, commonly known as Garcinia cambogia (syn.), is a popular traditional herbal medicine known for its role in treating obesity, and has been incorporated into several nutraceuticals globally for this purpose. The fruit rind is also used as a food preservative and a condiment because of its high content of hydroxycitric acid, which imparts a sharp, sour flavour. This review highlights the major bioactive compounds present in the tree Garcinia gummi-gutta, with particular emphasis on (2S, 3S)-tetrahydro-3-hydroxy-5-oxo-2,3-furan dicarboxylic acid, commonly referred to as garcinia acid. This acid can be isolated in large amounts through a simple procedure. Additionally, it explores the synthetic transformations of garcinia acid into biologically potent and functionally useful enantiopure compounds, a relatively under-documented area in the literature. This acid, with its six-carbon skeleton, a γ-butyrolactone moiety, and two chiral centres bearing chemically amenable functional groups, offers a versatile framework as a chiron for the construction of diverse molecules of both natural and synthetic origin. The synthesis of chiral 3-substituted and 3,4-disubstituted pyrrolidine-2,5-diones, analogues of the Quararibea metabolite—a chiral enolic-γ-lactone; the concave bislactone skeletons of fungal metabolites (+)-avenaciolide and (−)-canadensolide; the structural skeletons of the furo[2,3-b]furanol part of the anti-HIV drug Darunavir; (−)-tetrahydropyrrolo[2,1-a]isoquinolinones, an analogue of (−)-crispine A; (−)-hexahydroindolizino[8,7-b]indolones, an analogue of the naturally occurring (−)-harmicine; and furo[2,3-b]pyrroles are presented here. Full article

Natural ectoine, (+)-(4S)-2-methyl-1,4,5,6-tetrahydropyrimidine-4-carboxylic acid, is an extremely important small biomolecule belonging to the class of osmolytic/osmoprotective compounds. It stabilizes biomacromolecules such as DNA and proteins and protects them from denaturation by heat, dehydration, and UV radiation. The rapidly growing interest in this compound resulted in currently exclusive biotechnological production, while a chemical process along with enantioseparation as an alternative has not yet been established. An improved chemical synthesis of racemic ectoine starting from γ-butyrolactone in very good yield is described. Regioselective monoacetylation is achieved by the complexation of a copper(II)-ion with two molecules of 2,4-diamonobutyric acid in the key synthetic step. The racemic ectoine was synthesized with the aim of being successfully enantioseparated for the first time by high-performance liquid chromatography (HPLC) using a teicoplanin-based Chiral-T column in different solvent systems. The presence of (+)-ectoine was determined and quantified using an HPLC protocol on the Synergy Polar-RP column in fermentation broths inoculated with different strains of Streptomyces sp. bacteria isolated from the Adriatic Sea and grown on different NaCl concentrations. Full article

This study evaluates the utilization of in vitro embryo production (IVEP) technology for the conservation and breeding of the Auliekol cattle breed, a primary beef breed in Kazakhstan facing population decline due to the cessation of breeding programs and the incursion of transboundary diseases. We assessed the effect of consecutive ovum pick-up (OPU) procedures on oocyte yield and embryo production in Auliekol and Aberdeen Angus cows. A total of 2232 and 3659 oocytes were aspirated from Auliekol and Aberdeen Angus donors, respectively, with significantly higher yields and embryo production observed in Aberdeen Angus cows. The application of a meiotic block using Butyrolactone I (BLI) and subsequent in vitro fertilization (IVF) protocols was employed, with embryo development monitored up to the morula/blastocyst stage. Results indicated that Auliekol cows exhibited lower oocyte recovery, cleavage, and blastocyst rates compared to Aberdeen Angus cows, likely due to genetic characteristics. Despite the challenges, IVEP presents a valuable tool for the preservation and future propagation of the Auliekol breed, highlighting the need for further research to enhance reproductive outcomes and conservation strategies. Full article