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The determination of tobacco derived nicotine alkaloids in biofluid samples is of great importance to testing for tobacco use, tobacco cessation treatment, and studies on exposure to secondhand smoke. Paper spray mass spectrometry (MS) has been adapted for direct, quantitative analysis of tobacco alkaloids from biofluid samples, such as blood, urine, and saliva in liquid and dried form. Limits of quantitation as low as several nanograms per milliliter were obtained for nicotine, cotinine, trans-3'-hydroxycotinine, and anabasine. Direct analysis of fresh blood samples has also been achieved with improved sensitivity using print paper substrates of high density. Quantitation of the cotinine in the blood of a rat was performed with both direct analysis using paper spray and a traditional analysis protocol using liquid chromatography MS. Comparable results were obtained and the precision of the two methods was similar. The paper spray MS method is rapid and shows potential for significantly improved analytical efficiency in clinical laboratories as well as for point-of-care tobacco use assessment.

Background: Reactive Red (RR) 141 dye is widely used in various industrial applications, but its environmental impact remains a growing concern. In this study, the phytotoxic and genotoxic effects of RR 141 dye on mung bean seedlings (Vigna radiata (L.) Wilczek) were investigated, serving as a model for potential harm to plant systems., Methods and Results: Short-term (14 days) and long-term (60 days) experiments in paddy soil pot culture exposed mung bean seedlings to RR 141 dye. The dye delayed germination and hindered growth, significantly reducing germination percentage and seedling vigor index (SVI) at concentrations of 50 and 100 ml/L. In short-term exposure, plumule and radical lengths dose-dependently decreased, while long-term exposure affected plant length and grain weight, leaving pod-related parameters unaffected. To evaluate genotoxicity, high annealing temperature-random amplified polymorphic DNA (HAT-RAPD) analysis was employed with five RAPD primers having 58-75% GC content. It detected polymorphic band patterns, generating 116 bands (433 to 2857 bp) in plant leaves exposed to the dye. Polymorphisms indicated the appearance/disappearance of DNA bands in both concentrations, with decreased genomic template stability (GTS) values suggesting DNA damage and mutation., Conclusion: These findings demonstrate that RR 141 dye has a significant impact on genomic template stability (GTS) and exhibits phytotoxic and genotoxic responses in mung bean seedlings. This research underscores the potential of RR 141 dye to act as a harmful agent within plant model systems, highlighting the need for further assessment of its environmental implications., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

Background: Paper mulberry is one of the most common skin-lightening agents in the beauty industry due to its strong anti-tyrosinase activity. This narrative review aims to summarize the chemical composition, biological activities, and applications of paper mulberry in cosmetics. Method: The literature for this article was acquired from the PubMed, Web of Science, and Google Scholar databases before September 2022. The keywords for searching included "paper mulberry", "Broussonetia papyrifera", "skin-lightening", "skin-whitening", "depigmentation", "pharmacological activity", and "biological activity". Results: Paper mulberry consists of various components, including flavonoids, tannins, alkaloids, phenols, saponins, coumarins, glycosides, and polysaccharides, which possess a wide range of pharmacological properties. Apart from its anti-tyrosinase activity, paper mulberry and its compounds exhibited anti-inflammatory, antioxidant, antimicrobial, antiviral, anticancer, antidiabetic, anticholinesterase, antigout, antinociceptive, and hepatoprotective effects. Phenols and flavonoids were demonstrated to be the main contributors to the biological activities of paper mulberry. Paper mulberry is widely applied in cosmetics for skin lightening and skin moisturizing purposes and shows potential for application in hair care products due to the hair nourishing effects. The safety of paper mulberry for topical application was proven in clinical studies. Conclusion: The current review provides a better understanding of paper mulberry's properties and allows us to extend the application of this plant and its bioactive components in cosmetics. [ABSTRACT FROM AUTHOR]

We develop a capillary-paper spray (CPS) ion source which allows for sample separation in the capillary and enables rapid and sensitive paper spray (PS) mass spectrometry (MS) analysis of biofluids. The CPS employs a glass capillary to load liquid analytes, vertically standing at the rear of the PS. To further reduce the matrix effect, a nitrocellulose filter membrane is placed between the glass tube and chromatography paper to absorb proteins and other macromolecules, which is beneficial for the detection of the small molecules. Compared with the normal PS method, the CPS method markedly improves spray stability and prolongs analysis duration, and also generates significantly better signal intensities during the analysis of drugs, thus indicating its potential for clinical use. As a proof of concept, quantitative analysis of drugs (metformin hydrochloride and berberine hydrochloride) in serum is performed. [ABSTRACT FROM AUTHOR]

[Display omitted] • PVC-diphenylamine modified cellulose was proposed as sorptive phase. • The synthesis, using the dip-coating technique, is simple and cost-effective. • Opioids interact with the membrane by a mixed-mode interaction. • Direct infusion mass spectrometry allows to reduce the time of analysis. • The approach was successfully applied to real saliva samples containing codeine and tramadol. This article evaluates the potential of cellulose paper as a substrate for preparing a polyvinylchloride (PVC)-diphenylamine sorptive phase that can be used under the thin film microextraction (TFME) format. This phase was easily synthesized using the dip-coating technique to coat the filter paper with PVC, followed by the covalent bonding of diphenylamine. As a result, aromatics rings are available on paper surface to isolate the target analytes by a mixed-mode interaction at physiological pH. The resulting material was characterized by infrared spectroscopy, UV–Vis diffuse reflection spectroscopy, and scanning electron microscopy. As analytical problem, three opioids (methadone, codeine, and tramadol) were determined in saliva samples by direct infusion mass spectrometry. Different variables involved in the extraction procedure have been optimized (e.g. sample pH, extraction time, and sample dilution). The proposed method provides good linearity (R2 > 0.9817) and sensitivity (detection limits in the range from 1.5 µg L−1 to 15 µg L−1). The intra-day and inter-day precision, expressed as relative standard deviation, were better than 16.4 % and 18.5 % respectively. The accuracy, expressed as relative recovery, provides values in the interval from 82 % to 105 %. Finally, the proposed approach has been successfully applied to real saliva samples of patients under codeine and tramadol medical prescription. [ABSTRACT FROM AUTHOR]

Despite long-standing uses in several food and medicine traditions, the full potential of the leguminous crop fenugreek (Trigonella foenum-graecum L.) remains to be realized in the modern diet. Not only its seeds, which are highly prized for their culinary and medicinal properties, but also its leaves and stems abound in phytochemicals with high nutritional and health promoting attributes. Fenugreek dual food-medicine applications and reported metabolic activities include hypoglycemic, antihyperlipidemic, antioxidative, anti-inflammatory, antiatherogenic, antihypertensive, anticarcinogenic, immunomodulatory, and antinociceptive effects, with potential organ-protective effects at the cardiovascular, digestive, hepatic, endocrine, and central nervous system levels. Effectiveness in alleviating certain inflammatory skin conditions and dysfunctions of the reproductive system was also suggested. As a food ingredient, fenugreek can enhance the sensory, nutritional, and nutraceutical qualities of a wide variety of foods. Its high nutritive density can assist with the design of dietary items that meet the demand for novelty, variety, and healthier foods. Its seeds provide essential protective nutrients and other bioactive compounds, notably galactomannans, flavonoids, coumarins, saponins, alkaloids, and essential oils, whose health benefits, alone or in conjunction with other bioactives, are only beginning to be tapped into in the food industries. This review summarizes the current state of evidence on fenugreek potential for functional food development, focusing on the nutrients and non-nutrient bioactive components of interest from a dietary perspective, and their applications for enhancing the functional and nutraceutical value of foods and beverages. New developments, safety, clinical evidence, presumed mechanisms of action, and future perspectives are discussed. HIGHLIGHTS: Fenugreek seeds and leaves have long-standing uses in the food-medicine continuum. Fenugreek phytochemicals exert broad-spectrum biological and pharmacological activities. They show high preventive and nutraceutical potential against common chronic diseases. Current evidence supports multiple mechanisms of action mediated by distinct bioactives. Opportunities for fenugreek-based functional foods and nutraceuticals are expanding., (© 2024 Institute of Food Technologists.)

Background: Coffee cultivation and agroindustry generate residues that are rich in several metabolites. These compounds, such as phenolic compounds and alkaloids, are known for their antioxidant activity and are usually consumed as nutraceuticals. The purpose of this study was to evaluate the occurrence of chemical and antioxidant components of low-pruned coffee stems under different fertilizer regimes. Extractives and lignin composition, histochemical, chromatographic, and antioxidant analyses were performed., Results: Multiple compounds were found to accumulate in the stems of coffee trees. Furthermore, the presence of phenolic compounds such as chlorogenic acid, vanillin, resveratrol, and the alkaloids caffeine and trigonelline varied depending on the type of fertilization. In all samples examined, optimal performance was observed at the highest tested concentration (500 μg mL -1 ). All samples analyzed presented a great performance at the highest concentration tested (500 μg mL -1 ), with the dose 70% and the dose 100%, which is the recommended for the culture, showing the highest values for most of the concentrations and the best half-maximal inhibitory concentration (IC 50 ) when compared with the other samples tested., Conclusion: As shown in the results, the reuse of stem residues as antioxidant material, with the potential to be profitable, and has the added benefit of providing a sustainable destination for material that until now has been underutilized. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

The opium poppy (Papaver somniferum) is a global commercial crop that has been historically valued for both medicinal and culinary purposes. Naturally occurring opium alkaloids including morphine, codeine, thebaine, noscapine, and papaverine are found primarily in the latex produced by the plant. If the plant is allowed to fully mature, poppy seeds that do not contain the opium alkaloids will form within the pods and may be used in the food industry. It is possible for the seeds to become contaminated with alkaloids by the latex during harvesting, posing a potential health risk for consumers. In the USA, there have been more than 600 reported adverse events including 19 fatalities that may be linked to the consumption of a contaminated poppy-containing product such as home-brewed poppy seed tea. Unwashed poppy seeds and pods may be purchased over the Internet and shipped worldwide. The Forensic Chemistry Center, US Food and Drug Administration (FDA) has evaluated several mass spectrometers (MS) capable of rapid screening to be used for high-throughput analysis of samples such as poppy seeds. These include a direct analysis in real-time (DART) ambient ionization source coupled to a single-quadrupole MS, an atmospheric solids analysis probe (ASAP) ionization source coupled to the same MS, and ion mobility spectrometers (IMS). These instruments have been used to analyze 17 poppy seed samples for the presence of alkaloids, and the results were compared to data obtained using liquid chromatography with mass spectral detection (LC-MS/MS). Results from the 17 poppy seed samples indicate that the DART-MS, ASAP-MS, and IMS devices detect many of the same alkaloids confirmed during the LC-MS/MS analyses, although both the false-positive and false-negative rates are higher, possibly due to the non-homogeneity of the samples and the lack of chromatographic separation., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

A direct spirocyclization approach for the chemical synthesis of spiro[cyclohexane-2-indoline] alkaloids is reported. The absolute stereochemistry was introduced by a desymmetrizing Dieckmann condensation, and the relative stereochemistry was controlled by the manipulation of the kinetic and thermodynamic pathways of the spirocyclization. By contrast to the biogenetic proposal involving the diester-type alkaloid as the precursor, we demonstrate that chemically a common lactone-type intermediate could bridge the chemical synthesis of this class of natural products., (© 2022 Wiley-VCH GmbH.)

An electromembrane microextraction (EME)-assisted fluorescent molecularly imprinted polymer (MIP) sensing method is presented for detecting the total cathinone drugs in urine samples. In this detection system, the clean-up ability of EME eliminated the matrix effects on both target binding with MIPs and the luminescence of the fluorophore in the sensor. Moreover, by optimizing the extraction conditions of EME, different cathinone drugs with a same concentration show a same response on the single aggregation induced emission (AIE) based MIP (AIE-MIP) sensor (λ ex  = 360 nm, λ em  = 467 nm). The recoveries were 57.9% for cathinone (CAT) and 78.2% for methcathinone (MCAT). The EME-assisted "light-up" AIE-MIP sensing method displayed excellent performance with a linear range of 2.0-12.0 μmol L -1 and a linear determination coefficient (R 2 ) of 0.99. The limit of detection (LOD) value for EME-assisted "light-up" AIE-MIP sensing method was 0.3 μmol L -1 . The relative standard deviation (RSD) values for the detection were found to be within the range 2.0-12.0%. To the best of our knowledge, this is the first time that determination of total illicit drugs with a single fluorescent MIP sensor was achieved and also the first utilization of sample preparation to tune the sensing signal of the sensor to be reported. We believe that this versatile combination of fluorescent MIP sensor and sample preparation can be used as a common protocol for sensing the total amount of a group of analytes in various fields., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)

Monoterpene indole alkaloids (MIAs) are endowed with high structural and spatial complexity and characterized by diverse biological activities. Given this complexity-activity combination in MIAs, rapid and efficient access to chemical matter related to and with complexity similar to these alkaloids would be highly desirable, since such compound classes might display novel bioactivity. We describe the design and synthesis of a pseudo-natural product (pseudo-NP) collection obtained by the unprecedented combination of MIA fragments through complexity-generating transformations, resulting in arrangements not currently accessible by biosynthetic pathways. Cheminformatic analyses revealed that both the pseudo-NPs and the MIAs reside in a unique and common area of chemical space with high spatial complexity-density that is only sparsely populated by other natural products and drugs. Investigation of bioactivity guided by morphological profiling identified pseudo-NPs that inhibit DNA synthesis and modulate tubulin. These results demonstrate that the pseudo-NP collection occupies similar biologically relevant chemical space that Nature has endowed MIAs with., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Central nervous system (CNS) disease is one of the most important causes of human death. Because of their complex pathogenesis, more and more attention has been paid to them. At present, drug treatment of the CNS is the main means; however, most drugs only relieve symptoms, and some have certain toxicity and side effects. Natural compounds derived from plants can provide safer and more effective alternatives. Alkaloids are common nitrogenous basic organic compounds found in nature, which exist widely in many kinds of plants and have unique application value in modern medicine. For example, Galantamine and Huperzine A from medicinal plants are widely used drugs on the market to treat Alzheimer's disease. Therefore, the main purpose of this review is to provide the available information on natural alkaloids with the activity of treating central nervous system diseases in order to explore the trends and perspectives for the further study of central nervous system drugs. In this paper, 120 alkaloids with the potential effect of treating central nervous system diseases are summarized from the aspects of sources, structure types, mechanism of action and structure-activity relationship., (© 2023 John Wiley & Sons, Ltd.)

Developing drugs for Alzheimer's disease (AD) is an extremely challenging task due to its devastating pathology. Previous studies have indicated that natural compounds play a crucial role as lead molecules in the development of drugs. Even though, there are remarkable technological advancements in the isolation and synthesis of natural compounds, the targets for many of them are still unknown. In the present study, lobeline, a piperidine alkaloid has been identified as a cholinesterase inhibitor through chemical similarity assisted target fishing method. The structural similarities between lobeline and donepezil, a known acetylcholinesterase (AChE) inhibitor encouraged us to hypothesize that lobeline may also exhibit AChE inhibitory properties. It was further confirmed by in silico, in vitro and biophysical studies that lobeline could inhibit cholinesterase. The binding profiles indicated that lobeline has a higher affinity for AChE than BChE. Since excitotoxicity is one of the major pathological events associated with AD progression, we also investigated the neuroprotective potential of lobeline against glutamate mediated excitotoxicity in rat primary cortical neurons. The cell based NMDA receptor (NMDAR) assay with lobeline suggested that neuroprotective potential of lobeline is mediated through the blockade of NMDAR activity., (© 2023 International Union of Biochemistry and Molecular Biology.)

Synthetic cathinones, one of the most prevalent categories of new psychoactive substances, have been posing a serious threat to public health. Methylmethcathinones (MMCs), notably 3-MMC, have seen an alarming increase in their use in the last decade. The metabolism and toxicology of a large majority of synthetic cathinones, including 3-MMC and 2-MMC, remain unknown. Traditionally, male-derived liver materials have been used as in vitro metabolic incubations to investigate the metabolism of xenobiotics, including MMCs. Therefore, little is known about the metabolism in female-derived in vitro models and the potential sex-specific differences in biotransformation. In this study, the metabolism of 2-MMC, 3-MMC, and 4-MMC was investigated using female rat and human liver microsomal incubations, as well as male rat and human liver microsomal incubations. A total of 25 phase I metabolites of MMCs were detected and tentatively identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Seven sex-specific metabolites were detected exclusively using pooled male rat liver microsomal incubations. In addition, the metabolites generated from the sex-dependent in vitro metabolic incubations that were present in both male and female rat liver microsomal incubations showed differences in relative abundance. Yet, neither sex-specific metabolites nor significant differences in relative abundance were observed from pooled human liver microsomal incubations. This is the first study to report the phase I metabolic pathways of MMCs using in vitro metabolic incubations for both male and female liver microsomes, and the relative abundance of the metabolites observed from each sex., (© 2023. The Author(s).)

Sarpagine alkaloids are bioactive indole natural products that contain a highly rigid indole-fused 1-azabicyclo[2.2.2]octane, more than 100 members of which have been identified. Herein, a detailed examination of the intramolecular oxidative coupling between a ketone and a Weinreb amide for assembling the complex 1-azabicyclo[2.2.2]octane core structure of sarpagine family alkaloids is described. Precise late-stage manipulations of the ketone and Weinreb amide enable the divergent syntheses of (-)-trinervine, (+)-vellosimine, (+)-normacusine B, and (-)-alstomutinine C. Other notable transformations of the synthesis featured an aza-Achmatowicz/indole cyclization cascade to generate the azabicyclo[3.3.1]nonane structure, a regioselective elimination reaction to form the ethylidene motif embedded in the (+)-vellosimine and (+)-normacusine B structures, and a diastereoselective indole oxidative rearrangement to form the spirooxindole structure in (-)-alstomutinine C., (© 2023 Wiley-VCH GmbH.)

Cathinone, the main psychoactive compound found in the plant Catha edulis Forsk. (khat), is a β-keto analogue of amphetamine, sharing not only the phenethylamine structure, but also the amphetamine-like stimulant effects. Synthetic cathinones are derivatives of the naturally occurring cathinone that largely entered the recreational drug market at the end of 2000s. The former "legal status", impressive marketing strategies and their commercial availability, either in the so-called "smartshops" or via the Internet, prompted their large spread, contributing to their increasing popularity in the following years. As their popularity increased, the risks posed for public health became clear, with several reports of intoxications and deaths involving these substances appearing both in the social media and scientific literature. The regulatory measures introduced thereafter to halt these trending drugs of abuse have proved to be of low impact, as a continuous emergence of new non-controlled derivatives keep appearing to replace those prohibited. Users resort to synthetic cathinones due to their psychostimulant properties but are often unaware of the dangers they may incur when using these substances. Therefore, studies aimed at unveiling the pharmacological and toxicological properties of these substances are imperative, as they will provide increased expertise to the clinicians that face this problem on a daily basis. The present work provides a comprehensive review on history and legal status, chemistry, pharmacokinetics, pharmacodynamics, adverse effects and lethality in humans, as well as on the current knowledge of the neurotoxic mechanisms of synthetic cathinones., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Highlights • Quantitative determination of methylxanthines alkaloids in cocoa products. • Paper Spray mass spectrometry for analytical assay. • Comparison of obtained data with HPLC/UV method. Abstract A fast method for the determination of methylxanthines in cocoa products and drugs based on PS-MS/MS under MRM condition has been developed. Analyte ions were generated by applying a high voltage on a paper substrate drenched of sample extract using a small volume (∼15 μL) of spray solvent. The gas phase chemistry of the molecules under investigation has been elucidated. The accuracy values of the methodology ranged from 95 to 110%, while the analytical parameters LOQ, LOD, recovery and reproducibility, calculated analyzing spiked samples, confirmed the consistency of the proposed method. Furthermore, real samples have been analyzed both by the developed methodology and by using a classical HPLC-UV approach obtaining comparable values. [ABSTRACT FROM AUTHOR]

A convenient one-step synthesis of β-aminocyclobutane monoesters starting from commercially available reagents is reported. The obtained strained rings undergo (4+2) dearomative annulation with indole partners using silylium catalysis. This organocatalyzed annulation provided tricyclic indolines with four new stereocenters in up to quantitative yield and >95 : 5 diastereoselectivity and can proceed both intra- and intermolecularly. When performed intramolecularly, the tetracyclic structure of either akuamma or malagasy alkaloids was obtained selectively depending on the temperature of the reaction. This divergent outcome could be rationalized based on DFT calculations., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

The daphnezomine A-type subfamily of Daphniphyllum alkaloids structurally features a unique aza-adamantane core skeleton and anticipates efficient strategies for completing their syntheses to thoroughly investigate their biological activities. Herein, divergent total syntheses of (-)-daphnezomines A and B and (+)-dapholdhamine B have been accomplished in 16-20 steps from a known epoxide via rapid construction of a common core intermediate. The present work features a Ti-mediated radical cyclization to establish the azabicyclo[3.3.1]nonane ring system, an intramolecular Heck reaction to install the bridgehead all-carbon quaternary stereocenter, a tandem deprotection/reduction/keto amine-carbinolamine tautomerization to furnish the aza-adamantane backbone, and an NIS-promoted 6-endo-trig aminocyclization to assemble the (+)-dapholdhamine B backbone., (© 2023 Wiley-VCH GmbH.)

Many chemically-defended/aposematic species rely on diet for sequestering the toxins with which they defend themselves. This dietary acquisition can lead to variable chemical defenses across space, as the community composition of chemical sources is likely to vary across the range of (an aposematic) species. We characterized the alkaloid content of two populations of the Dyeing Poison Frog (Dendrobates tinctorius) in northeastern French Guiana. Additionally, we conducted unpalatability experiments with naive predators, Blue Tits (Cyanistes caeruleus), using whole-skin secretion cocktails to assess how a model predator would respond to the defense of individuals from each population. While there was some overlap between the two D. tinctorius populations in terms of alkaloid content, our analysis revealed that these two populations are markedly distinct in terms of overall alkaloid profiles. Predator responses to skin secretions differed between the populations. We identified 15 candidate alkaloids (including three previously undescribed) in seven classes that are correlated with predator response in one frog population. We describe alkaloid profile differences between populations for D. tinctorius and provide a novel method for assessing unpalatability of skin secretions and identifying which toxins may contribute to the predator response. In one population, our results suggest 15 alkaloids that are implicated in predator aversive response. This method is the first step in identifying the causal link between alkaloids and behavioral responses of predators, and thus makes sense of how varying alkaloid combinations are capable of eliciting consistent behavioral responses, and eventually driving evolutionary change in aposematic characters (or characteristics)., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Understanding the stability of analyzed drugs in biological samples is a crucial part for an appropriate interpretation of the analytical findings. Synthetic cathinones, as psychoactive stimulants, belong to a major class of new psychoactive substances. As they are subject to several degradation pathways, they are known to clinical and forensic toxicologists as unstable analytes in biological samples. When interpreting analytical data of synthetic cathinones in biological samples, analysts must be aware that the concentration of analytes may not accurately reflect the levels at the time they were acquired owing to many factors. This review provides (i) an overview of the current scientific knowledge on the stability of synthetic cathinones and/or metabolites in various human biological samples with a focus on factors that may deteriorate their stability-such as storage temperature, length of storage, matrix, pH, type of preservatives, concentration of analytes, and the chemistry of the analytes-and (ii) possible solutions on how to avoid such degradation. The PubMed database as well as Google Scholar was thoroughly searched to find published studies on the stability of synthetic cathinones since 2007 by searching specific keywords. A total of 23 articles met the inclusion criteria and were included in this review. Synthetic cathinones that carry methylenedioxy or N-pyrrolidine ring showed higher degradation resistance over other substituted groups. Acidification of samples pH plays a crucial role at increasing the stability of cathinones even with analytes that were frequently considered as poorly stable. This review also provides several recommendations for best practice in planning the experimental design, preservation, and storage conditions in order to minimize synthetic cathinones' degradation in human biological samples., (© 2020 The Authors. Drug Testing and Analysis published by John Wiley & Sons Ltd.)

We report herein the asymmetric total synthesis of periglaucines A-C, N,O-dimethyloxostephine and oxostephabenine. The key strategies used include: 1) a Rh I -catalyzed regio- and diastereoselective Hayashi-Miyaura reaction to connect two necessary fragments; 2) an intramolecular photoenolization/Diels-Alder (PEDA) reaction to construct the highly functionalized tricyclic core skeleton bearing a quaternary center; 3) a bio-inspired intramolecular Michael addition and transannular acetalization to generate the aza[4.4.3]propellane and the tetrahydrofuran ring., (© 2022 Wiley-VCH GmbH.)

Weeds cause destructive agricultural losses, so weed control is an urgent challenge facing agriculture. The extensive use of synthetic chemical herbicides has detrimental environmental impacts and promotes the emergence of resistant species. Therefore, in this study we tried to find a new natural weed control that can ensure biosafety and eco-sustainability. The phytotoxic potential of culture filtrates of the endophytes Bacillus inaquosorum NL1 and Bacillus safensis NL2 isolated from Nerium oleander leaf against the invasive harmful weed species Cenchrus echinatus was evaluated. Culture filtrates of both bacterial species exhibited potent phytotoxic activity, which resulted in 100% germination inhibition of C. echinatus. The chemical analysis of culture filtrates revealed high contents of total phenolics and n-alkanes that have phytotoxic effects against seed germination. According to the findings of this study the endophytic bacteria associated with N. oleander leaf can be used in the future to develop a sustainable bio-herbicide formulation., (© 2023. The Author(s).)

This book describes a unique class of secondary metabolites, the mono- and dimeric naphthylisoquinoline alkaloids. They occur in lianas of the paleotropical Ancistrocladaceae and Dioncophyllaceae families, exclusively. Their unprecedented structures include stereogenic centers and rotationally hindered, and thus likewise stereogenic, axes. Extended recent investigations on six Ancistrocladus species from Asia, as reported in this review, shed light on their fascinating phytochemical productivity, with over 100 such intriguing natural products. This high chemodiversity arises from a likewise unique biosynthesis from acetate-malonate units, following a novel polyketidic pathway to plant-derived isoquinoline alkaloids. Some of the compounds show most promising antiparasitic activities. Likewise presented are strategies for the regio- and stereoselective total synthesis of the alkaloids, including the directed construction of the chiral axis., (© 2023. The Author(s), under exclusive license to Springer Nature Switzerland AG.)

It is reported herein that by exploiting the commonly shared bicyclic decahydroquinoline motif, a gold-catalyzed enamide-alkyne cycloisomerization reaction is developed to access tricyclic cores in a simple way. These tricyclic cores further serve as an advanced platform for the divergent enantioselective collective total syntheses of five Lycopodium alkaloids, belonging to three different structural types, in a concise and protecting-group-free fashion. The key transformations in the second phase include: 1) a transannular reductive Heck cyclization for installation of the azepane ring in fawcettidine, fawcettimine, and lycoposerramine Q; 2) a domino Mukaiyama hydration/Grob fragmentation process for construction of the ten-membered lactam system in phlegmariurine B; 3) a Fukuyama one-pot protocol for the construction of the 2-pyridone motif in lycoposerramine R. The newly developed strategy is expected to pave the way for the synthesis of other structurally related Lycopodium alkaloids., (© 2022 Wiley-VCH GmbH.)

1,3-trans-Disubstituted tetrahydroisoquinoline (THIQ) is a common heterocyclic structural unit of naphthylisoquinoline alkaloids. The assembly of this structural unit is not trivial, which constitutes a substantial challenge in the total synthesis of naphthylisoquinoline alkaloids and related pharmaceuticals. Herein, we report a modular and convergent method for the rapid assembly of 1,3-trans-disubstituted THIQ frameworks through a three-component Catellani reaction and a Au I -catalyzed cyclization/reduction cascade. With widely available simple aryl iodides, aziridines and (triisopropylsilyl)acetylene as the building blocks, this method paves a practical way for the diversity-oriented synthesis of 1,3-trans-disubstituted THIQs. Based on this new method, concise syntheses of an analogue of the new drug mevidalen and four naphthylisoquinoline alkaloids have been accomplished, demonstrating the broad synthetic utility of this approach., (© 2022 Wiley-VCH GmbH.)

We have shown previously that the processing of asparagine-linked oligosaccharides in baby hamster kidney (BHK) cells is blocked only partially by the glucosidase inhibitors, 1-deoxynojirimycin and N-methyl-1-deoxynojirimycin [Hughes, R. C., Foddy, L. & Bause, E. (1987) Biochem. J. 247, 537-544]. Similar results are now reported for castanospermine, another inhibitor of processing glucosidases, and a detailed study of oligosaccharide processing in the inhibited cells is reported. In steady-state conditions the major endo-H-released oligosaccharides contained glucose residues but non-glycosylated oligosaccharides, including Man9GlcNAc to Man5GlcNAc, were also present. To determine the processing sequences occurring in the presence of castanospermine, BHK cells were pulse-labelled for various times with [3H]mannose and the oligosaccharide intermediates, isolated by gel filtration and paper chromatography, characterized by acetolysis and sensitivity to jack bean alpha-mannosidase. The data show that Glc3Man9GlcNAc2 is transferred to protein and undergoes processing to produce Glc3Man8GlcNAc2 and Glc3Man7GlcNAc2 as major species as well as a smaller amount of Man9GlcNAc2. Glucosidase-processed intermediates, Glc1Man8GlcNAc2 and Glc1Man7GlcNAc2, were also obtained as well as a Man7GlcNAc2 species derived from Glc1Man7GlcNAc2 and different from the Man7GlcNAc2 isomer formed in the usual processing pathway. No evidence for the direct transfer of non-glucosylated oligosaccharides to proteins was obtained and we conclude that the continued assembly of complex-type glycans in castanospermine-inhibited BHK cells results from residual activity of processing glucosidases.

Bases were extractable from dried, powdered grass material by percolation with methanol. The bases were removed from the methanol by cation-exchange resins and subsequently removed from the resins. Isolation of bases by these methods eliminated the problems associated with the use of large quantities of chlorinated solvents and formation of emulsions found in previously described isolation methods. The bases were separated by paper and thin-layer chromatography (TLC). TLC and a spectrodensitometer were used to quantify the principal alkaloids in crude extracts of tall fescue samples. This procedure recovered all of the alkaloids in spiked samples, and the standard deviation for perlolidine and perloline in tall fescue samples was 3% or less of the mean value.

A concise total synthesis of (±)-myrioneurinol has been achieved in 14 steps. An efficient AgSbF 6 /t-BuCl-catalyzed intramolecular [2+2] cycloaddition reaction of the alkynone-tethered enamine was developed to prepare the highly strained cyclobutene. It was used in combination with a subsequent retro-Mannich fragmentation/Mannich reaction to efficiently construct the tricyclic core of myrioneurinol., (© 2022 Wiley-VCH GmbH.)

We have achieved the divergent total synthesis of four kopsane alkaloids which share a complex heptacyclic caged ring system. Key transformations include an asymmetric Diels-Alder reaction to assemble the central bicyclo[2.2.2]octane moiety and the quaternary stereocenter at C20, a SmI 2 -mediated cascade reduction/aldol reaction to construct the five-membered ring and the quaternary stereocenter at C7, and a late-stage cascade reductive amination/cyclization to establish the highly strained caged ring system., (© 2022 Wiley-VCH GmbH.)

Representation of mass spectrometry analysis with paper spray ionization using different solvents in araticum samples. [Display omitted] • Different araticum fruit parts were evaluated for their chemical profile. • Three solvents were tested; • The fruit, in general, is composed of acetogenins and alkaloids; • The ethanol solvent extracted a more significant number of compounds; • The global evaluation showed that the samples are grouped by the part of the fruit studied regardless of the solvent. The Brazilian cerrado is considered one of the most critical biomes in the world. Araticum (Annona crassiflora Mart.) is a native plant from the Brazilian cerrado, abundant in nutrients and highly energetic. This study aimed to obtain chemical fingerprints of different parts of the araticum fruit, i.e. pulp, peel, and seed. Extracts from these three parts were prepared using different solvents (ethanol, water, and mixtures of ethanol and water) and later analyzed by paper spray ionization mass spectrometry. In general, ethanol extracted more metabolites than the other solvents. The chemical profiles varied according to the fruit part, geographic location, and extractor solvent. Among the metabolites, acetogenins (62.3%) and alkaloids (20.7%) predominated. Principal component analyses revealed that the samples were grouped according to the fruit part, regardless of the extractor solvent used. Araticum shows remarkable potential due to the beneficial properties of the metabolites for human health. The insertion of araticum in the human diet is still underexplored but is a promising alternative. [ABSTRACT FROM AUTHOR]

Introduction: The roots of Stephania succifera are used in traditional medicine for the treatment of several diseases. Research on this plant has mainly focused on bioactive alkaloids from the roots, and no previous work on compounds from the abundant leaves has yet been reported., Objective: To identify and compare alkaloidal compounds in S. succifera roots and leaves and to predict the potential bioactivity of some alkaloids., Methods: High-performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry (HPLC-QTOF-MS/MS) was employed to identify alkaloidal compounds from S. succifera. The potential targets and bioactivities of most alkaloids were predicted using the PharmMapper server., Results: Fifty-six alkaloidal compounds, including protoberberine-, aporphine-, proaporphine-, benzylisoquinoline-, and lactam-type alkaloids, were identified or tentatively identified in S. succifera roots and leaves based on the HPLC-MS data. Forty-one compounds have not been previously reported in S. succifera and eight of them have not been previously reported in the literature. Twenty-four alkaloidal compounds were found in both roots and leaves. Twelve potential targets with different indications were predicted for some alkaloids., Conclusion: Comparison of chemical constituents and their potential bioactivities for S. succifera roots and leaves indicated that diverse bioactive alkaloids were present in the leaves as well as the roots. PharmMapper provided new directions for bioactivity screening. This study will be helpful for further understanding the medicinal components of S. succifera and the rational utilisation of plant resources., (© 2021 John Wiley & Sons, Ltd.)

The first total syntheses of the Stemona alkaloid dehydrostenine A and the structure assigned to dehydrostenine B have been completed from a simple pyrrole substrate in 10 and 11 steps, respectively. Two independent Brønsted-acid-mediated intramolecular Michael additions were exploited to construct the tetracyclic dehydrostenine core. As a result of synthetic studies and associated analysis of the relevant literature, revisions of the structures originally assigned to dehydrostenines A and B are proposed., (© 2021 Wiley-VCH GmbH.)

Former study suggests alkaloids from herbs of Aconitum genus plants possess excellent bioactivities, which exert great value for related deeper chemical constituent investigation. Herein, chemical isolation was performed and four alkaloids were isolated from Fuzi, of which two were new ones, and the other two were reported NMR data for the first time. Their chemical structures were identified by NMR data, high resolution MS, UV and IR analysis. Additionally, the MS fragmentation patterns were explored, formerly, that of hetisane alkaloid was rarely reported, and fragmentation mechanism of the diagnostic ion was proposed. Based on these fragment pathway, metabolites and metabolic pathways of four compounds were investigated in rat liver microsomes using UPLC-Q/TOF-MS, and dehydrogenation product was firstly found from metabolites of hetisane alkaloid., (© 2021 Wiley-VHCA AG, Zurich, Switzerland.)