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The structural, conformational, and spectroscopic properties in the gas phase of 20 bicyclic monoterpenes and monoterpenoids have been analyzed by a new accurate, reduced-cost computational strategy. In detail, the revDSD-PBEP86 double-hybrid functional in conjunction with the D3BJ empirical dispersion corrections and a suitable triple-zeta basis set provides accurate geometrical parameters, whence equilibrium rotational constants, which are further improved by proper account of core–valence correlation. Average deviations within 0.1% between computed and experimental rotational constants are reached when taking into account the vibrational corrections obtained by the B3LYP functional in conjunction with a double-zeta basis set in the framework of second-order vibrational perturbation theory. In addition to their intrinsic interest, the studied terpenes further extend the panel of systems for which the proposed strategy has provided accurate results at density functional theory cost. Therefore, a very accurate yet robust and user-friendly tool is now available for systematic investigations of the role of stereo-electronic effects on the properties of large systems of current technological and/or biological interest by experimentally oriented researchers. [ABSTRACT FROM AUTHOR]

The genus Artemisia belongs to the Asteraceae family, known for its many pharmacological properties. This study focuses on the chemical characterization of two Algerian species: Artemisia absinthium (AA) and Artemisia herba-alba (AHA). Samples from eight different stations were subjected to four extraction procedures using hexane as solvent: maceration, reflux, Soxhlet, and ultrasound. After determining the yield, total phenolics were quantified in the 32 samples. In addition, the antioxidant activity of the extracts was evaluated by three tests (i.e. TAC, DPPH, and β-Carotene assays). The results showed that the reflux method was able to isolate low levels of phenols but presented a better antioxidant activity, compared to the other extraction protocols. Regarding the two plant species, A. absinthium revealed a higher antioxidant power. GC–MS analysis led us to identify a total of 68 chemical constituents from all hexane samples of the two species. Extracts were mainly dominated by fatty acids (FAs), monoterpenoids and sesquiterpenoids, without any significant variability based on the applied method. HPLC-DAD analysis proved that the highest content in artemisinin was present in A. absinthium extracts obtained by Soxhlet, with an amount estimated at 15.09 ± 0.62 µg per mg of plant material, followed by ultrasound extraction. [ABSTRACT FROM AUTHOR]

Two uncharacterized monoterpenoids (1 – 2) and six known analogues (3 – 8) were isolated from the fruit of Gardenia jasminoides. Their structures were determined by comprehensive spectroscopic data analysis, and the absolute configuration of 2 was elucidated by comparing the calculated electronic circular dichroism (ECD) spectrum with experimental ECD spectrum. Additionally, the results of preliminary activity evaluation indicated that these compounds showed slightly α -glucosidase inhibitory activity. [Display omitted] • Two undescribed monoterpenoids were isolated from the fruit of Gardenia jasminoides Ellis. • The isolated compounds were evaluated for their α-glucosidase inhibitory activity. [ABSTRACT FROM AUTHOR]

Tanacetum vulgare L., tansy, is a perennial plant with highly variable terpenoid composition, with mono‐ and sesquiterpenoids being the most abundant. The high diversity of terpenoids plays an important role in mediating ecological interactions. However, the distribution of terpenoids in different tissues and inducibility of terpenoids in these tissues via biotic stress are poorly understood. We investigated changes in terpenoid profiles and concentrations in different organs following treatment of roots with pipecolic acid (Pip), a non‐proteinogenic amino acid that triggers defence responses leading to induce systemic resistance (SAR) in plants. Tansy leaves and midribs contained mainly monoterpenoids, while coarse and fine roots contained mainly sesquiterpenoids. Rhizomes contained terpenoid profiles of both midribs and roots but also unique compounds. Treatment with Pip led to an increase in concentrations of mono‐ and sesquiterpenoids in all tissues except rhizomes. However, significantly more sesquiterpenoids was formed in root tissues in response to Pip treatment, compared to shoots. The metabolic atlas for terpenoids presented here shows that there is exceptionally strong differentiation of terpenoid patterns and terpenoid content in different tissues of tansy. This, together with differential inducibility by Pip, suggests that the chemical diversity of terpenoids may play an important role in tansy ecological interactions and defence against biotic stressors that feed on below‐ and aboveground organs. [ABSTRACT FROM AUTHOR]

A series of bispidine conjugates bearing monoterpene moieties and either l-proline or l-phenylalanine residues was synthesized. The synthesized bispidines can catalyze asymmetric ethylation of benzaldehydes with diethylzinc. The highest enantioselectivity of the addition reaction (ee 24%) was achieved for bispidine with (–)-α-pinene and Boc-l-proline moieties. [ABSTRACT FROM AUTHOR]

New optically active arylsulfonamides, including carane-containing streptocide analogs, were synthesized by the reaction of carane amino alcohols with tosyl- and N-acetylsulfanilyl chlorides. Sulfonamide, which was prepared based on (–)-4β-amino-3α-hydroxy-cis-carane, was studied by X-ray diffraction. The synthesized sulfonamides and the starting amino alcohols were evaluated for antimicrobial activity. [ABSTRACT FROM AUTHOR]

Geraniol and citronellol are monoterpenoid alcohols with diverse pharmacological activities. This research focuses on synthesized of geranyl laurate and citronellyl laurate using silica gel as an esterification catalyst. The FTIR peak spectra of silica gel showed that Si-OH, Si-O-Si group were observed. XRD showed that the silica gel is an amorphous phase. The reaction was conducted under reflux using a Dean-Stark trap. The reaction was monitored by TLC and then the product was purified using column chromatography. This work reported that silica gel can be utilized as a catalyst for preparing geranyl laurate and citronellyl laurate which proven by the spectra of FTIR, ¹H-NMR, and 13CNMR of the geranyl laurate and citronellyl laurate formed. The IR spectra of geranyl laurate and citronellyl laurate showed the presence of a carbonyl group (C=O) at 1744-1745 cm-1 and C-O from ester at 1170-1176 cm-1. The peak number and its chemical shift on ¹H-NMR and 13C-NMR spectra further verified the structure of geranyl laurate and citronellyl laurate. In conclusion, silica gel can be utilised as a catalyst for preparing geranyl laurat and citronellyl laurate. Therefore, a silica gel-based catalyst is promising to be developed for esterification applications. [ABSTRACT FROM AUTHOR]

Terpenes and terpenoids content in cannabis plant was already studied in the past with three used methods. Since these works did not compare the content of these substances under the same conditions, we tried to make this comparison exactly. Three different gas chromatography/mass spectrometry (GS/MS) methods—hexane-based liquid extraction (Lis), static headspace extraction (HS), and headspace solid-phase microextraction (SPME)—were compared to identify volatile compounds in four different cannabis chemotypes—Green fields chemotype, Titan chemotype, Black Domina chemotype, and Neptune chemotype. The main compounds focused on were monoterpenes/monoterpenoids and sesquiterpenes/sesquiterpenoids. For a final evaluation of the comparison of the three methods of analysis, hexane extraction gives comparable results (which is advantageous for quantitative analysis), although the other two methods allowed the identification of more substances. This means that the same method should be used everywhere for the quantitative evaluation of constituents in cannabis. [ABSTRACT FROM AUTHOR]

The aim of this work was the investigation of novel organocatalysts for the Michael addition of diethyl malonate to β-nitrostyrene. The methodology of the study included NMR titration, reaction monitoring by NMR spectroscopy and electrospray ionization mass spectrometry (ESI-MS), product characterization by MALDI, IR spectroscopy, scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), and elemental analysis. As a result, evidence of supramolecular interactions between two pairs of components of the reaction was found. In addition to the supramolecular complexes, an unusual reaction, i.e., the Michael addition of NH-bispidines to β-nitrostyrene, was found, which led to previously unknown oligomers of β-nitrostyrene. A new mechanism for the catalytic action of NH-bispidine was proposed, which involved catalysis not by the initial organocatalyst but rather by its adduct with β-nitrostyrene. Thus, in this reaction, N-benzylbispidine acted as an initiator, and the real catalyst was the betaine formed during the initiation stage.

Two new monoterpenoid indole alkaloids, named taberibogines E and F (1 and 2), together with three known ones (3–5) were isolated from the stems of Tabernaemontana bovina Lour (Apocynaceae). Their structures including absolute configurations were elucidated from a combination of NMR and HRESIMS data and NMR calculations as well as DP4+ probability analyses. Compounds 1 and 2 exhibited inhibitory effects on LPS-induced nitric oxide (NO) production in RAW 264.7 macrophages. [ABSTRACT FROM AUTHOR]

The chemical composition of Sedum ewersii Ledeb., a plant indigenous to Kazakhstan and traditionally utilized in folk medicine, was comprehensively investigated, with a focus on its various plant parts. Fresh samples collected in May 2023 from the Almaty region underwent hydrodistillation to extract volatile components, followed by analysis using gas chromatography coupled with mass spectrometric detection, which identified a total of 71 compounds across different plant parts, including the root (underground part), root (aerial part), leaf, stem, and flowering aerial part. The predominant biologically active compound identified across all plant parts was Ethyl α-D-glucopyranoside. Monoterpenes, recognized as primary secondary metabolites, were notably abundant in each plant part, with varying compositions: the root (underground part) contained 28.58% aliphatic monoterpenes, 54.41% oxygenated monoterpenoids, 1.42% diterpenoids, and 15.59% other compounds; the root (aerial part) exhibited 1.34% aliphatic monoterpenes, 31.28% oxygenated monoterpenoids, 6.16% diterpenoids, and 61.22% other compounds; the stem and leaves showed 3.06% aliphatic monoterpenes, 21.49% oxygenated monoterpenoids, 17.99% diterpenoids, and 57.46% other compounds; and the flowering aerial part displayed 8.20% aliphatic monoterpenes, 53.18% oxygenated monoterpenoids, 23.75% diterpenoids, and 14.87% other compounds. Diterpenes, particularly Phytol, were prominently present in the leaf, stem, and flowering aerial parts. Additionally, a diverse array of organic acids, ketones, and phenolic compounds were identified across the plant parts, each potentially offering distinct pharmacological benefits. The presence of exclusive compounds in specific plant parts, such as Dihydroxyacetone in the root (aerial part), underscored the pharmacological diversity of S. ewersii. This study provides valuable insights into the chemical diversity and pharmacological potential of S. ewersii, suggesting promising applications in pharmaceutical and medicinal fields. Further research aimed at elucidating the individual and synergistic pharmacological effects of these compounds is crucial to fully harness the therapeutic benefits of this plant. [ABSTRACT FROM AUTHOR]

SUMMARY: Monoterpene synthases (MTSs) catalyze the first committed step in the biosynthesis of monoterpenoids, a class of specialized metabolites with particularly high chemical diversity in angiosperms. In addition to accomplishing a rate enhancement, these enzymes manage the formation and turnover of highly reactive carbocation intermediates formed from a prenyl diphosphate substrate. At each step along the reaction path, a cationic intermediate can be subject to cyclization, migration of a proton, hydride, or alkyl group, or quenching to terminate the sequence. However, enzymatic control of ligand folding, stabilization of specific intermediates, and defined quenching chemistry can maintain the specificity for forming a signature product. This review article will discuss our current understanding of how angiosperm MTSs control the reaction environment. Such knowledge allows inferences about the origin and regulation of chemical diversity, which is pertinent for appreciating the role of monoterpenoids in plant ecology but also for aiding commercial efforts that harness the accumulation of these specialized metabolites for the food, cosmetic, and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

The article presents a study on the use of eucalyptus oil as a remedy for agriculture crop protection. Topics discussed include variables that impacted eucalyptus oil's output and chemical make-up, pharmaceutical applications of eucalyptus oil, and antioxidant properties of the monoterpenoid-rich oil extract Eucalyptus teriticornis.

Mugil liza juveniles (6.69 ± 0.06 g) were subjected to dietary citral (0-control, 0.5, 1.0 and 2.0 mL per kg feed) for 45 days, and its possible effects on zootechnical and metabolic parameters, digestive enzymes, innate immunity, oxidative status and liver damage were evaluated. At the end of the experiment, fish fed 2.0 mL citral per kg feed showed a greater weight gain and protein retention efficiency, as well as enhanced activities of pepsin (stomach) and amylase (intestine) compared with control fish. Citral supplementation decreased liver lipoperoxidation and increased the activities of glutathione peroxidase, glutathione-S-transferase and superoxide dismutase in the gills, liver and brain. The highest level of citral inclusion augmented non-protein thiol content in the brain and gills. Myeloperoxidase activity was lower in fish offered 1.0 and 2.0 mL citral per kg feed. Dietary citral did not influence the plasma levels of aspartate aminotransferase and alanine aminotransferase or the hepatic histology. As it improved growth, the activity of digestive enzymes and general health, dietary citral may be recommended for M. liza at 2.0 mL per kg feed. [ABSTRACT FROM AUTHOR]

The aim of this review is to present the potential application of camphor—a bicyclic monoterpene ketone—in the prevention of skin infections. Skin diseases represent a heterogeneous group of disorders characterized by prolonged symptoms that significantly diminish the quality of life. They affect the dermis, the epidermis, and even subcutaneous tissue. They very often have a bacterial or fungal background. Therapy for dermatological skin disorders is difficult and long-term. Therefore, it is important to find a compound, preferably of natural origin, that (i) prevents the initiation of this infection and (ii) supports the skin's repair process. Based on its documented anti-inflammatory, antibacterial, antifungal, anti-acne, anesthetic, strengthening, and warming properties, camphor can be used as a preventative measure in dermatological infectious diseases and as a component in medical and cosmetic products. This work discusses the structure and physicochemical properties of camphor, its occurrence, and methods of obtaining it from natural sources as well as through chemical synthesis. The use of camphor in industrial preparations is also presented. Additionally, after a detailed review of the literature, the metabolism of camphor, its interactions with other medicinal substances, and its antimicrobial properties against bacteria and fungi involved in skin diseases are discussed with regard to their resistance. [ABSTRACT FROM AUTHOR]

The aim of this work was the investigation of novel organocatalysts for the Michael addition of diethyl malonate to β-nitrostyrene. The methodology of the study included NMR titration, reaction monitoring by NMR spectroscopy and electrospray ionization mass spectrometry (ESI-MS), product characterization by MALDI, IR spectroscopy, scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), and elemental analysis. As a result, evidence of supramolecular interactions between two pairs of components of the reaction was found. In addition to the supramolecular complexes, an unusual reaction, i.e., the Michael addition of NH-bispidines to β-nitrostyrene, was found, which led to previously unknown oligomers of β-nitrostyrene. A new mechanism for the catalytic action of NH-bispidine was proposed, which involved catalysis not by the initial organocatalyst but rather by its adduct with β-nitrostyrene. Thus, in this reaction, N-benzylbispidine acted as an initiator, and the real catalyst was the betaine formed during the initiation stage. [ABSTRACT FROM AUTHOR]

Summary: In Catharanthus roseus, monoterpenoid indole alkaloids (MIAs) are produced through the cooperation of four cell types, with final products accumulating in specialized cells known as idioblasts and laticifers. To explore the relationship between cellular differentiation and cell type‐specific MIA metabolism, we analyzed the expression of MIA biosynthesis in germinating seeds.Embryos from immature and mature seeds were observed via stereomicroscopy, fluorescence microscopy, and electron microscopy. Time‐series MIA and iridoid quantification, along with transcriptome analysis, were conducted to determine the initiation of MIA biosynthesis. In addition, the localization of MIAs was examined using alkaloid staining and imaging mass spectrometry (IMS).Laticifers were present in embryos before seed maturation. MIA biosynthesis commenced 12 h after germination. MIAs accumulated in laticifers of embryos following seed germination, and MIA metabolism is induced after germination in a tissue‐specific manner.These findings suggest that cellular morphological differentiation precedes metabolic differentiation. Considering the well‐known toxicity and defense role of MIAs in matured plants, MIAs may be an important defense strategy already in the delicate developmental phase of seed germination, and biosynthesis and accumulation of MIAs may require the tissue and cellular differentiation. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) poses an emanating threat to humanity's future. The effectiveness of commonly used antibiotics against microbial infections is declining at an alarming rate. As a result, morbidity and mortality rates are soaring, particularly among immunocompromised populations. Exploring alternative solutions, such as medicinal plants and iodine, shows promise in combating resistant pathogens. Such antimicrobials could effectively inhibit microbial proliferation through synergistic combinations. In our study, we prepared a formulation consisting of Aloe barbadensis Miller (AV), Thymol, iodine (I2), and polyvinylpyrrolidone (PVP). Various analytical methods including SEM/EDS, UV-vis, Raman, FTIR, and XRD were carried out to verify the purity, composition, and morphology of AV-PVP-Thymol-I2. We evaluated the inhibitory effects of this formulation against 10 selected reference strains using impregnated sterile discs, surgical sutures, gauze bandages, surgical face masks, and KN95 masks. The antimicrobial properties of AV-PVP-Thymol-I2 were assessed through disc diffusion methods against 10 reference strains in comparison with two common antibiotics. The 25-month-old formulation exhibited slightly lower inhibitory zones, indicating changes in the sustained-iodine-release reservoir. Our findings confirm AV-PVP-Thymol-I2 as a potent antifungal and antibacterial agent against the reference strains, demonstrating particularly strong inhibitory action on surgical sutures, cotton bandages, and face masks. These results enable the potential use of the formulation AV-PVP-Thymol-I2 as a promising antimicrobial agent against wound infections and as a spray-on contact-killing agent. [ABSTRACT FROM AUTHOR]

Background Myrcene and cymene, aromatic monoterpenes found in plants and essential oils, possess distinctive aromatic qualities. However, their volatility and limited solubility pose challenges in precise handling and formulation. Meanwhile, nanoemulsions emerge as promising drug delivery systems, improving the bioavailability and stability of these active ingredients. Objective This article aimed to develop an HPLC method for the quantification of two monoterpenoids, p-cymene and myrcene, in nanoemulsions. Method The method used a Phenomenex® Synergi™ Fusion-RP column (150 mm × 4.6 mm id, 4 μm particle size) on an HPLC system with isocratic elution. The mobile phase was composed of acetonitrile and water (60:40, v/v) and was validated in terms of specificity, linearity, accuracy, precision, robustness, and selectivity. Results The method provided accurate and precise results with a correlation coefficient of 0.999 and RSD values of less than 2%. The method can be used for quality control of nanoemulsions containing these monoterpenoids and as a reference for future studies on their efficacy and stability. Conclusions The study demonstrates the feasibility of using HPLC for the quantification of monoterpenoids in nanoemulsions and its potential as a quality control tool for nanoemulsion-based drug delivery systems. Highlights The method's accuracy, precision, and reliability, as evidenced by high correlation coefficients and low RSD values, underscore its suitability for ensuring the consistent formulation of these monoterpenoid-containing nanoemulsions, while also serving as a reference point for future research endeavors in this field. [ABSTRACT FROM AUTHOR]

Carvacrol expresses a wide range of biological activities, but the studies of its mechanisms focused on bacteria, mainly involving the destruction of the plasma membrane. In this study, carvacrol exhibited strong activities against several phytopathogenic fungi and demonstrated a novel antifungal mechanism against Lasiodiplodia theobromae. RNA sequencing indicated that many genes of L. theobromae hyphae were predominately induced by carvacrol, particularly those involved in replication and transcription. Hyperchromic, hypsochromic, and bathochromic effects in the UV-visible absorption spectrum were observed following titration of calf thymus DNA (ctDNA) and carvacrol, which indicated the formation of a DNA–carvacrol complex. Circular dichroism (CD) spectroscopy indicated that the response of DNA to carvacrol was similar to that of 4′,6-diamidino-2-phenylindole (DAPI) but different from that of ethidium bromide (EB), implying the ionic bonds between carvacrol and ctDNA. Fluorescence spectrum (FS) analysis indicated that carvacrol quenched the fluorescence of double-stranded DNA (dsDNA) more than single-stranded DNA, indicating that carvacrol mainly bound to dsDNA. A displacement assay showed that carvacrol reduced the fluorescence intensity of the DNA–DAPI complex through competition with DAPI, but this did not occur for DNA–EB. The FS assay revealed that carvacrol bound to the AAA sequence on the minor groove of ds-oligonucleotides. The hydroxyl of carvacrol was verified to bind to ctDNA through a comparative test in which structural analogs of carvacrol, including thymol and 4-ethyl-1,2-dimethyl, were analyzed. The current study indicated carvacrol can destruct plasma membranes and bind to the minor groove of DNA, inhibiting fungal proliferation by disturbing the stability of dsDNA. [ABSTRACT FROM AUTHOR]

Hamelia patens (Rubiaceae), known as firebush, is a source of bioactive monoterpenoid oxindole alkaloids (MOAs) derived from monoterpenoid indole alkaloids (MIAs). With the aim of understanding the regulation of the biosynthesis of these specialized metabolites, micropropagated plants were elicited with jasmonic acid (JA) and salicylic acid (SA). The MOA production and MIA biosynthetic-related gene expression were evaluated over time. The production of MOAs was increased compared to the control up to 2-fold (41.3 mg g DW−1) at 72 h in JA-elicited plants and 2.5-fold (42.4 mg g DW−1) at 120 h in plants elicited with SA. The increment concurs with the increase in the expression levels of the genes HpaLAMT, HpaTDC, HpaSTR, HpaNPF2.9, HpaTHAS1, and HpaTHAS2. Interestingly, it was found that HpaSGD was downregulated in both treatments after 24 h but in the SA treatment at 120 h only was upregulated to 8-fold compared to the control. In this work, we present the results of MOA production in H. patens and discuss how JA and SA might be regulating the central biosynthetic steps that involve HpaSGD and HpaTHAS genes. [ABSTRACT FROM AUTHOR]

This article discusses the collective total synthesis of β-carboline-type monoterpenoid indole alkaloid glycosides. These alkaloids are found in higher plants and have medicinal applications. The authors describe the synthesis of several specific alkaloids, including lyaloside, ophiorines A and B, and correantosine F. They also detail the development of a new decyanation/oxidation reaction using a cyano group, which allows for the efficient synthesis of β-carboline compounds. The authors successfully synthesized these alkaloids and are currently evaluating their bioactivity. [Extracted from the article]

Many monoterpenoid indole alkaloids (MIAs) produced in Catharanthus roseus have demonstrated biological activities and clinical potential. However, their complex biosynthesis pathway in plants leads to low accumulation, limiting therapeutic applications. Efforts to elucidate the MIA biosynthetic regulatory mechanism have focused on improving accumulation levels. Previous studies revealed that jasmonic acid (JA), an important plant hormone, effectively promotes MIA accumulation by inducing the expression of MIA biosynthesis and transport genes. Nevertheless, excessive JA signaling can strongly inhibit plant growth, decreasing MIA productivity in C. roseus. Therefore, identifying key components balancing growth and MIA production in the JA signaling pathway is imperative for effective pharmaceutical production. Here, we identify a homolog of the jasmonate transporter 1, CrJAT1, through co-expression and phylogenetic analyses. Further investigation demonstrated that CrJAT1 can activate JA signaling to promote MIA accumulation without compromising growth. The potential role of CrJAT1 in redistributing intra/inter-cellular JA and JA-Ile may calibrate signaling to avoid inhibition, representing a promising molecular breeding target in C. roseus to optimize the balance between growth and specialized metabolism for improved MIA production. [ABSTRACT FROM AUTHOR]

Linalool is a pleasant-smelling monoterpenoid widely found in the essential oils of most flowers. Due to its biologically active properties, linalool has considerable commercial potential, especially in the food and perfume industries. In this study, the oleaginous yeast Yarrowia lipolytica was successfully engineered to produce linalool de novo. The (S)-linalool synthase (LIS) gene from Actinidia argute was overexpressed to convert geranyl diphosphate (GPP) into linalool. Flux was diverted from farnesyl diphosphate (FPP) synthesis to GPP by introducing a mutated copy of the native ERG20F88W−N119W gene, and CrGPPS gene from Catharanthus roseus on its own and as part of a fusion with LIS. Disruption of native diacylglycerol kinase enzyme, DGK1, by oligo-mediated CRISPR-Cas9 inactivation further increased linalool production. The resulting strain accumulated 109.6 mg/L of linalool during cultivation in shake flasks with sucrose as a carbon source. CrGPPS expression in Yarrowia lipolytica increased linalool accumulation more efficiently than the ERG20F88W−N119W expression, suggesting that the increase in linalool production was predominantly influenced by the level of GPP precursor supply. [ABSTRACT FROM AUTHOR]

A series of new compounds containing monoterpenoid fragments, sulfide and carboxy groups was synthesized. The reaction of monoterpene thiols with bromoacetic acid and ethyl 2-bromo-2,2-difluoroacetate afforded new thiomonoterpene carboxylic acids in 80–96% and 56–80% yields, respectively. The synthesized compounds were studied for antimicrobial activity. Some structure–property interrelations were revealed, which depended on the monoterpene fragment structure and the presence of fluorine atoms in the carboxymethyl group. [ABSTRACT FROM AUTHOR]

Tyrosyl-DNA phosphodiesterase 1 (TDP1) is a DNA repair enzyme that can reduce the efficacy of some anticancer drugs targeting topoisomerase 1 (TOP1) making it a promising target for antitumor therapy when combined with TOP1 poisons. Here we describe the synthesis of a number of adamantane-monoterpene conjugates 20a–g and 21a–g connected through a 1,3,4-thiadiazol-2(3H)-imine linker, where acyclic, monocyclic, and bicyclic structural types of monoterpenes were used. All the synthesized compounds demonstrated activity against TDP1 in micromolar range, with the most potent inhibitor being compound 21a (IC50 1.2 μM). The cytotoxic effects of these compounds determined in the HEK293A and HeLa cell lines were low to moderate. These findings imply that such compounds are promising for further development of new TDP1 inhibitors with favorable physicochemical properties. [ABSTRACT FROM AUTHOR]

Poratrioza sinica (Hemiptera: Psyllidae) is a highly destructive pest that infests of wolfberry. To screen biodegradable and safe insecticides, 12 representative monoterpenoids in essential oils were evaluated for their acute toxicity, synergistic or antagonistic effects on adult P. sinica. The modified residual film method was used to test the toxicity of individual and binary mixture of these monoterpenoids against adult P. sinica. The effects of these monoterpenoids on acetylcholinesterase (AChE) and glutathione S-transferase (GST) activities in P. sinica were assessed in vitro. Correlation between numbers of synergistic or antagonistic binary mixtures and AChE or GST activities was analyzed. The results showed that 2-ethylimidazole had the strongest acute toxicity against P. sinica adult, with a median lethal concentration (LC50) value of 0.52 g/L. Among the 66 binary mixtures, 19 showed strong synergistic effects, while 21 showed antagonistic effects. The most profound synergistic effect was the mixture of l-carvone and dihydrocarvone, with an expected mortality of 35.2% and actual mortality of 98.4%. Estragole had the highest frequency of antagonistic effect (7 combinations), and the most significant antagonism was observed when combining β-pinene and estragole, with an expected mortality of 29.0% and actual mortality of 3.8%. Furthermore, AChE inhibition was observed with estragole, cuminaldehyde, and 1,8-cineole displayed high potency. L-carvone showed the highest GST inhibition activity, followed by cuminaldehyde. Pearson correlation analysis revealed a significant negative correlation between GST inhibition rate and number of antagonistic binary mixtures. In conclusion, our findings suggest that 2-ethylimidazole and cuminyl alcohol have high toxicity against P. sinica. L-carvone was the best synergist, and binary mixtures of l-carvone with dihydrocarvone, cuminaldehyde, cuminyl alcohol, d-carvone, and estragole showed potential as control agents against P. sinica. This study provides insights for identifying safe and biodegradable insecticides and potential solutions for controlling P. sinica. [ABSTRACT FROM AUTHOR]

Monoterpenoids are interesting hydrocarbons typically found in essential oils and have a significant role in medicinal and biological purposes. The goal of this study was to investigate the effects of two monoterpenoids, carvacrol (CAR) and menthol (MEN), supplemented with Moringa oleifera leaf meal (MOLM) based diets on growth parameters, digestibility and body composition of Nile tilapia (Oreochromis niloticus). Alongside the basal diet (control-T1), nine experimental diets supplemented with categorized levels of CAR and MEN at 200, 300 and 400 mg/kg individually and their mixtures (MIX) (1:1) (CAR-T2, 200; T3, 300; T4, 400 mg/kg, MEN-T5, 200; T6, 300; T7, 400 mg/kg and MIX- (1:1) T8, 200; T9, 300; T10, 400 mg/kg) were fed to the fingerlings (6.55 ± 0.03 g) for the period of 60 days. Monoterpenoids supplementation led to significantly (p

The first asymmetric total synthesis of the monoterpenoid indole alkaloid arboduridine has been accomplished. The tricyclic A/B/D ring system was constructed by an enantioselective Michael reaction followed by intramolecular nucleophilic addition. Intramolecular α‐amination of a ketone forged the piperidine ring, while a Horner–Wadsworth–Emmons (HWE) reaction was used to form the pyrrolidine ring. A reduction cyclization cascade led to formation of the tetrahydrofuran ring. [ABSTRACT FROM AUTHOR]

The fascinating structural features and potential biological activities of aspidofractinine monoterpenoid indole alkaloids grasped the attention of synthetic community since 1964. Aspidofractinine also serves as the primary structural component to over 200 monoterpenoid indole alkaloids, in which most of these alkaloids' total synthesis has been unexplored. In light of these facts, studies on synthetic strategies towards the complex, intriguing carbon skeleton of aspidofractinine have high implications. The intensive studies on the total synthesis of aspidofractinine alkaloids have resulted in numerous elegant strategies to construct the highly substituted hexacyclic core structure containing bicyclo[2.2.2]octane motif and three all‐carbon quaternary stereogenic centers. This review discusses all reported strategies for synthesizing aspidofractinine, and aspidofractinine‐like alkaloids. [ABSTRACT FROM AUTHOR]

Conjugates of isatin and hydrazones based on (+)-camphor and (–)-fenchone were synthesized for the first time. The physicochemical properties of the synthesized compounds have been studied, and for the hydrazone product of fenchone and isatin X-ray diffraction data have been obtained. Molecular modeling of the possible interaction of new compounds with the active site of the basic protease 3CLpro of the SARS-CoV-2 virus was carried out, and the properties of isatin-terpene compounds as inhibitors of the 3CLpro protease were studied. It was found that the new conjugates do not exhibit inhibitory properties against 3CLpro, which makes it possible to clarify the direction of further chemical modifications of monoterpenoid derivatives in order to obtain molecules with antiviral properties. [ABSTRACT FROM AUTHOR]

Wall-associated kinases (WAKs) are a unique family of proteins that are predominantly localized on the plasma membrane and simultaneously bound to the cell wall. WAKs play a pivotal role in signal transduction to regulate growth, defense, and response to environmental stimuli in plants. These kinases have been identified and characterized in various plant species, however, similar information for Catharanthus roseus is scarce. C. roseus is an evergreen ornamental plant that produces a repertoire of biologically active compounds. The plant is best characterized for the production of antineoplastic monoterpenoid indole alkaloids (MIAs) namely vinblastine and vincristine. Owing to the diverse composition of phytochemicals, C. roseus is known as a "model non-model" plant for secondary metabolite research. Genome analyses showed 37 putative CrWAK genes present in C. roseus, largely localized on the plasma membrane. Phylogenetic analysis revealed six clusters of CrWAKs. Diverse cis-acting elements, including those involved in defense responses, were identified on the promotor regions of CrWAK genes. The highest binding affinity (− 12.6 kcal/mol) was noted for CrWAK-22 against tri-galacturonic acid. Tri-galacturonic acid stimulated 2.5-fold higher production of vinblastine, sixfold upregulation of the expression of ORCA3 transcription factor, and 6.14-fold upregulation of CrWAK-22 expression. Based on these results it was concluded that the expression of CrWAK genes induced by biotic elicitors may have an important role in the production of MIAs. The current findings may serve as a basis for functional characterization and mechanistic explanation of the role of CrWAK genes in the biosynthesis of MIAs upon elicitation. [ABSTRACT FROM AUTHOR]

The chemical analysis on petroleum ether extract of Artemisia argyi resulted in the identification of 11 terpenoids, including an undescribed monocyclic monoterpenoid, artemisinicol A (1), along with ten known compounds (2–11). Their structures were elucidated by extensive spectroscopic analysis (including 1D, 2D NMR, and HR-MS) and ECD calculation. The in vitro tumor growth inhibitory property of the compound 1 was further assessed. [ABSTRACT FROM AUTHOR]

New camphor and fenchon anils, promising materials for the needs of medicine and industry, as well as some of their reduced forms, were synthesized and characterized. In a number of cases, the reduction by the NaBH4—NiCl2 • 6H2O reagent system in EtOH containing water was accompanied by the formation of side products of the aromatic ring hydrogenation in up to 10–18% yields. Aniline derivatives containing a cage monoterpenoid fragment at the nitrogen atom were studied for antibiotic activity in vitro against gram-positive and gram-negative bacteria, yeasts, and imperfect fungi. The results obtained in the Halobacterium salinarum test system allowed us to identify the most active compounds and draw a conclusion about good prospects for the further structural modification in this chemotype series of compounds. [ABSTRACT FROM AUTHOR]

Plectranthus amboinicus (Lour.) Spreng is a perennial plant belonging to the Lamiaceae family which is found naturally in the tropics and warm regions of Australia, Asia and Africa. This plant has therapeutic properties (antioxidant, anti-inflammatory, antimicrobial, antitumor, antiepileptic and analgesic activities) attributed to its phytochemical compounds (76 volatiles and 30 non-volatile compounds belonging to different classes of phytochemicals such as monoterpenoids, diterpenoids, triterpenoids, sesquiterpenoids, phenolics, flavonoids, esters, alcohols and aldehydes), which are highly valued in the pharmaceutical industry. P. amboinicus is widely used in traditional medicine to treat respiratory, cardiovascular, digestive, urinary and skin conditions such as cold, cough, fever, asthma, constipation, headache and skin diseases. In recent years, due to the increased interest in herbal treatments, numerous research studies have been conducted to document the traditional uses of P. amboinicus and to find new biological effects of this plant. This review provides comprehensive information on the biological properties and bioactive compounds responsible for the therapeutic effects of P. amboinicus. [ABSTRACT FROM AUTHOR]

Monoterpenoid indole alkaloids (MIAs) represent a major class of active ingredients from the plants of the genus Gelsemium. Gelsemium MIAs with diverse chemical structures can be divided into six categories: gelsedine-, gelsemine-, humantenine-, koumine-, sarpagine- and yohimbane-type. Additionally, gelsemium MIAs exert a wide range of bioactivities, including anti-tumour, immunosuppression, anti-anxiety, analgesia, and so on. Owing to their fascinating structures and potent pharmaceutical properties, these gelsemium MIAs arouse significant organic chemists' interest to design state-of-the-art synthetic strategies for their total synthesis. In this review, we comprehensively summarised recently reported novel gelsemium MIAs, potential pharmacological activities of some active molecules, and total synthetic strategies covering the period from 2013 to 2022. It is expected that this study may open the window to timely illuminate and guide further study and development of gelsemium MIAs and their derivatives in clinical practice. [ABSTRACT FROM AUTHOR]

This article discusses the bioinspired total synthesis of secologanin-related natural products, which are important in drug discovery. Secologanin is a key intermediate in the biosynthesis of over 3000 monoterpenoid indole alkaloids and hetero-oligomeric iridoid glycosides. The authors present the development of practical synthetic protocols for the synthesis of secologanin and its derivatives, as well as the total syntheses of various natural products derived from secologanin. They hope that these syntheses will contribute to the efficient preparation of a library of natural products for drug discovery. The authors successfully synthesized a range of complex natural products, including glycosylated monoterpenoid indole alkaloids, pentacyclic alkaloids, and hetero-oligomeric iridoid glycosides, using bioinspired transformations. They also highlight the potential reactivity of secologanin and its role in the construction of diverse natural product libraries. [Extracted from the article]

Turnera is a genus of plants whose biological activity has been widely studied. The importance of this genus, particularly Turnera diffusa, as a source of treatment for various conditions is evidenced by the large number of new studies that have evaluated its biological activity. Accordingly, the objective of this review was to compile the information published in the last ten years concerning the biological activities reported for Turnera spp. The present work includes 92 publications that evaluate 29 bioactivities and toxicological and genotoxic information on five species of this genus. Among the pharmacological effects reported, the antioxidant, hepatoprotective, neuroprotective, hypoglycemic, and aphrodisiac activities seem more promising. Phytochemicals and standardized plant extracts could offer alternative therapeutic remedies for various diseases. Although several flavonoids, cyanogenic glycosides, monoterpenoids, triterpenoids, and fatty acids have been isolated for Turnera plants, future research should focus on the identification of the main active principles responsible for these pharmacological activities, as well as to perform clinical trials to support the laboratory results. [ABSTRACT FROM AUTHOR]

Two approaches to the synthesis of para-menthene epoxide ((1S,5S,6R)-4) are developed. The first approach includes a reaction between chlorohydrin 7 and NaH in THF. The second involves the formation of epoxide in the reaction of corresponding diacetate 6 with sodium tert-butoxide. One possible mechanism of this reaction is proposed to explain unexpected outcomes in the regio- and stereospecificity of epoxide (1S,5S,6R)-4 formation. The epoxide ring in (1S,5S,6R)-4 is then opened by various S- and O-nucleophiles. This series of reactions allows for the stereoselective synthesis of diverse derivatives of the monoterpenoid Prottremine 1, a compound known for its antiparkinsonian activity, including promising antiparkinsonian properties. [ABSTRACT FROM AUTHOR]

Ligustrum robustum has been not only used as a heat-clearing and detoxicating functional tea (Ku-Ding-Cha) but also consumed as a hypotensive, anti-diabetic, and weight-reducing folk medicine. From the leaves of L. robustum, ten new monoterpenoid glycosides named ligurobustosides T10 (1a), T11 (1b), T12 (2a), T13 (2b), T14 (3a), T15 (3b), F1 (4b), T16 (5a), T17 (5b), and E1 (6b), together with five known ones (4a, 6a, 7, 8a, 8b), were separated and identified using the spectroscopic method and chemical method in this research. The results of biological tests exhibited that the fatty acid synthase (FAS) inhibitory action of compound 5 (IC50: 4.38 ± 0.11 μM) was as strong as orlistat (IC50: 4.46 ± 0.13 μM), a positive control; the α-glucosidase inhibitory actions of compounds 1–4 and 7–8, and the α-amylase inhibitory actions of compounds 1–8 were medium; the ABTS radical scavenging capacities of compounds 1–3 and 5–8 (IC50: 6.27 ± 0.23 ~ 8.59 ± 0.09 μM) were stronger than l-(+)-ascorbic acid (IC50: 10.06 ± 0.19 μM) served as a positive control. This research offered a theoretical foundation for the leaves of L. robustum to prevent diabetes and its complications. [ABSTRACT FROM AUTHOR]

Monoterpene thiols are one of the classes of natural flavors that impart the smell of citrus fruits, grape must and wine, black currants, and guava and are used as flavoring agents in the food and perfume industries. Synthetic monoterpene thiols have found an application in asymmetric synthesis as chiral auxiliaries, derivatizing agents, and ligands for metal complex catalysis and organocatalysts. Since monoterpenes and monoterpenoids are a renewable source, there are emerging trends to use monoterpene thiols as monomers for producing new types of green polymers. Monoterpene thioderivatives are also known to possess antioxidant, anticoagulant, antifungal, and antibacterial activity. The current review covers methods for the synthesis of acyclic, mono-, and bicyclic monoterpene thiols, as well as some investigations related to their usage for the preparation of the compounds with antimicrobial properties. [ABSTRACT FROM AUTHOR]

Candida albicans is an opportunistic yeast that causes most fungal infections. C. albicans has become increasingly resistant to antifungal drugs over the past decade. Our study focused on the identification of pure natural compounds for the development of antifungal medicines. A total of 15 natural compounds from different chemical families (cinnamic derivatives, aromatic phenols, mono- and sesquiterpenols, and unclassified compounds) were screened in this study. Among these groups, hinokitiol (Hi), a natural monoterpenoid extracted from the wood of the cypress family, showed excellent anti-C. albicans activity, with a MIC value of 8.21 µg/mL. Hi was selected from this panel for further investigation to assess its antifungal and anti-inflammatory properties. Hi exhibited significant antifungal activity against clinically isolated fluconazole- or caspofungin-resistant C. albicans strains. It also reduced biofilm formation and hyphal growth. Treatment with Hi protected Caenorhabditis elegans against infection with C. albicans and enhanced the expression of antimicrobial genes in worms infected with C. albicans. Aside from its antifungal activities against C. albicans, Hi challenge attenuated the LPS-induced expression of pro-inflammatory cytokines (IL-6, IL-1β, and CCL-2) in macrophages. Overall, Hi is a natural compound with antifungal and anti-inflammatory properties, making Hi a promising platform with which to fight against fungal infections. [ABSTRACT FROM AUTHOR]

Mugil liza juveniles (6.69 ± 0.06 g) were subjected to dietary citral (0-control, 0.5, 1.0 and 2.0 mL per kg feed) for 45 days, and its possible effects on zootechnical and metabolic parameters, digestive enzymes, innate immunity, oxidative status and liver damage were evaluated. At the end of the experiment, fish fed 2.0 mL citral per kg feed showed a greater weight gain and protein retention efficiency, as well as enhanced activities of pepsin (stomach) and amylase (intestine) compared with control fish. Citral supplementation decreased liver lipoperoxidation and increased the activities of glutathione peroxidase, glutathione-S-transferase and superoxide dismutase in the gills, liver and brain. The highest level of citral inclusion augmented non-protein thiol content in the brain and gills. Myeloperoxidase activity was lower in fish offered 1.0 and 2.0 mL citral per kg feed. Dietary citral did not influence the plasma levels of aspartate aminotransferase and alanine aminotransferase or the hepatic histology. As it improved growth, the activity of digestive enzymes and general health, dietary citral may be recommended for M. liza at 2.0 mL per kg feed.

The investigation of monoterpenes as natural products has gained significant attention in the search for new pharmacological agents due to their ability to exhibit a wide range in biological activities, including antifungal, antibacterial, antioxidant, anticancer, antispasmodic, hypotensive, and vasodilating properties. In vitro and in vivo studies reveal their antidepressant, anxiolytic, and memory-enhancing effects in experimental dementia and Parkinson's disease. Chemical modification of natural substances by conjugation with various synthetic components is a modern method of obtaining new biologically active compounds. The discovery of new potential drugs among monoterpene derivatives is a progressive avenue within experimental pharmacology, offering a promising approach for the therapy of diverse pathological conditions. Biologically active substances such as monoterpenes, for example, borneol, camphor, geraniol, pinene, and thymol, are used to synthesize compounds with analgesic, anti-inflammatory, anticonvulsive, antidepressant, anti-Alzheimer's, antiparkinsonian, antiviral and antibacterial (antituberculosis) properties. Myrtenal is a perspective monoterpenoid with therapeutic potential in various fields of medicine. Its chemical modifications often lead to new or more pronounced biological effects. As an example, the conjugation of myrtenal with the established pharmacophore adamantane enables the augmentation of several of its pivotal properties. Myrtenal–adamantane derivatives exhibited a variety of beneficial characteristics, such as antimicrobial, antifungal, antiviral, anticancer, anxiolytic, and neuroprotective properties, which are worth examining in more detail and at length. [ABSTRACT FROM AUTHOR]

Summary: Polyploidization and transposon elements contribute to shape plant genome diversity and secondary metabolic variation in some edible crops. However, the specific contribution of these variations to the chemo‐diversity of Lamiaceae, particularly in economic shrubs, is still poorly documented. The rich essential oils (EOs) of Lavandula plants are distinguished by monoterpenoids among the main EO‐producing species, L. angustifolia (LA), L. × intermedia (LX) and L. latifolia (LL). Herein, the first allele‐aware chromosome‐level genome was assembled using a lavandin cultivar 'Super' and its hybrid origin was verified by two complete subgenomes (LX‐LA and LX‐LL). Genome‐wide phylogenetics confirmed that LL, like LA, underwent two lineage‐specific WGDs after the γ triplication event, and their speciation occurred after the last WGD. Chloroplast phylogenetic analysis indicated LA was the maternal source of 'Super', which produced premium EO (higher linalyl/lavandulyl acetate and lower 1,8‐cineole and camphor) close to LA. Gene expression, especially the monoterpenoid biosynthetic genes, showed bias to LX‐LA alleles. Asymmetric transposon insertions in two decoupling 'Super' subgenomes were responsible for speciation and monoterpenoid divergence of the progenitors. Both hybrid and parental evolutionary analysis revealed that LTR (long terminal repeat) retrotransposon associated with AAT gene loss cause no linalyl/lavandulyl acetate production in LL, and multi‐BDH copies retained by tandem duplication and DNA transposon resulted in higher camphor accumulation of LL. Advances in allelic variations of monoterpenoids have the potential to revolutionize future lavandin breeding and EO production. [ABSTRACT FROM AUTHOR]

A number of new octahydro-2H-chromene acetamide derivatives based on the monoterpenoid (−)-isopulegol were synthesized using a one-pot three-component Prins—Ritter reaction. The structure of the target compounds was determined using 1H and 13C NMR spectroscopy, high resolution mass spectrometry, and X-ray diffraction analysis. Most of the products exhibited high analgesic activity in in vivo tests. The highest analgesic activity was found for spirocyclic compound (4S)-2d, the effect of which is apparently mediated through the dopamine system. It was shown that compound (4S)-2d has a low acute toxicity. [ABSTRACT FROM AUTHOR]

The article presents a collection of research studies featured in the periodical "Chinese Journal of Chemistry" in 2023. Topics including the creation of an innovative biosensor using interfacial polymer-engineered field effect transistors for swift detection of the SARS-CoV-2 N antigen. It outlines the studies delve into areas such as ultralong organic phosphorescence for dynamic data encryption and anti-counterfeiting.