Germacrane-type sesquiterpenes from Artemisia atrovirens and their anti-inflammatory activity.

Artemisia plants are well-known for their abundant sesquiterpene compounds, which encompass various structural types and exhibit a range of biological activities. In this study, a systematic investigation of Artemisia atrovirens revealed the presence of germacrane-type sesquiterpenes for the first time. This included the discovery of 10 new compounds and three known analogues, among which were two rare dimeric germacrane-type compounds. Their structures were fully characterized through a comprehensive analysis involving MS, IR, 1D- and 2D-NMR spectroscopic data, single crystal X-ray diffraction, density functional theory (DFT) NMR calculations, and time-dependent DFT electronic circular dichroism (TDDFT ECD) calculations. Furthermore, all isolated compounds were evaluated for their anti-inflammatory activity in LPS-stimulated RAW 264.7 murine macrophages. Compound 10 demonstrated a potent inhibitory effect on NO production, with an IC50 value of 4.01 ±â€¯0.09 µM. This study highlights the diverse chemical repertoire of Artemisia species and underscores their potential in drug discovery and development.

12-Nor-rotenoids and other cytotoxic constituents of Pachyrhizus erosus seeds.

Five previously undescribed compounds, including three 12-nor-rotenoids, were isolated from Pachyrhizus erosus seeds. A brief survey on the dealkylation of selected rotenoids with BBr3 was undertaken. Spectroscopic data of these previously undescribed compounds and reaction products are reported. The proposal of absolute configurations at stereocenters in the isolates and reaction products was based on NMR and ECD data. Most of the isolates and reaction products were evaluated for their growth inhibitory activities against four cancer cell lines and a Vero cell line. Many compounds exhibited strong to moderate activities with IC50 values ranging from 0.06 to 20.9 µM, and their structure-activity relationships were evaluated.

Germacrane-type sesquiterpenes from Pilea cavaleriei Levl. subsp. cavaleriei.

The first systematic investigation of germacrane-type sesquiterpenes from Pilea cavaleriei Levl. subsp. cavaleriei was conducted. Eleven undescribed germacrane analogues named cavalinols A-K were identified. Their planar structures were determined by extensive analysis of 1D and 2D NMR spectroscopic data, and the absolute configurations were further determined by X-ray single crystal diffraction, Mosher method, and time dependent density functional theory (TDDFT) electron circular dichroism (ECD) calculation, with the aid from DFT NMR calculation and NOESY experiment. Except for the common 10-memebered ring, ten new compounds contained a p-coumaroyl sidechain connected to C-8 of the nucleus skeleton. All the isolated compounds were screened for anti-inflammatory activity in LPS stimulated RAW 264.7 cells, and compounds 5 and 6 showed moderate activity.

Harzianolides B-G: Undescribed Butenolides isolated from the fungus Trichoderma harzianum ZN-4.

Five undescribed γ-butyrolactones harzianolides BF (1-5), one precursor harzianolide G (6) along with two known analogues, were isolated and identified from the EtOAc extract of the liquid fermentation of Trichoderma harzianum ZN-4, which was obtained from the sediment of Zhoushan coastal area. Notably, compound 1 featured an unusual carbon skeleton with methylene-bridged furan rings system. Their structures were determined by detailed interpretation of NMR and mass spectroscopic data, and the absolute configurations were unambiguously established based on ECD quantum chemical calculations. In bioassay, 1 and 7 showed inhibitory activity against Pestalotiopsis theae, with MIC values of 25 and 50 µg/mL, respectively.

Retrobisabolane A, a Novel Bisabolane-Derived Sesquiterpenoid Isolated from Deep-Sea-Derived Fungus Retroconis fusiformis MCCC 3A00792.

One novel bisabolane-derived sesquiterpenoid retrobisabolane A (1), featuring a methyl group location at the C-4 position instead of C-3 in the bisabolanes, and a known ester-substituted eremophilane-type sesquiterpenoid cryptosphaerolide (2), along with three known indole alkaloids (3-5) were discovered from the fermented cultures of a deep-sea-derived fungus Retroconis fusiformis MCCC 3A00792. The planar structure of new compound 1 was determined by extensive analysis of the NMR and HRESIMS spectra. The relative and absolute configurations of 1 were resolved by the coupling constant (J), calculation of ECD and NMR spectra, and the DP4+ probability analysis of the 1H and 13C NMR data. Interestingly, retrobisabolane A was the new subclass of bisabolanes bearing a methyl group linkage at C-4 instead of C-3 position. Three human cancer cell lines (Hela, AGS, and BIU-87) were subjected to evaluate the cytotoxic activities of compounds 1-5. As a result, compound 2 exhibited significant inhibitory activities against three cell lines with IC50 values ranging from 9.95 to 18.77 µM.

Proliferacorins A-M: Thirteen undescribed acorane sesquiterpenoids isolated from the fungus Fusarium proliferatum.

In this study, 13 previously undescribed acorane sesquiterpenoids, namely, proliferacorins A-M, were isolated from the solid fermentation of Fusarium proliferatum. Their structures and absolute configurations were confirmed via spectroscopic analyses, quantum-chemical NMR calculations with DP4+ probability analyses, ECD calculations and comparisons, and single-crystal X-ray diffraction techniques. Proliferacorins A-E (1-5) have a 7-oxa-tricyclo[6.3.1.01,5]tridecane decorated with a rare ether bridge between C-7 and C-11, while proliferacorin F (6) possesses a 7-oxa-tricyclic[6.4.0.01,5]dodecane skeleton with an unusual ether bond between C-6 and C-11. Proliferacorins C and D (3 and 4) are a pair of isomers at the carbon bridge between C-5 and C-7, whereas proliferacorins H and I (8 and 9) are a pair of spiro carbon isomers. All isolates were tested for their cytotoxic, anti-inflammatory, and immunosuppressive activities.

New autophagy-modulating lanostane-type triterpenoids from a hallucinogenic poisonous mushroom Gymnopilus orientispectabilis.

Gymnopilus orientispectabilis, also known as "big laughter mushroom," is a hallucinogenic poisonous mushroom that causes excessive laughter upon ingestion. From the fruiting bodies of G. orientispectabilis, eight lanostane-type triterpenoids (1-8), including seven novel compounds: gymnojunols A-G (2-8), were isolated. The chemical structures of these new compounds (2-8) were determined by analyzing their 1D and 2D NMR spectra and HR-EISMS, and their absolute configurations were unambiguously assigned by quantum chemical ECD calculations and a computational method coupled with a statistical procedure (DP4+). Upon evaluating autophagic activity, compounds 2, 6, and 7 increased LC3B-II levels in HeLa cells to a similar extent as bafilomycin, an autophagy inhibitor. In contrast, compound 8 decreased the levels of both LC3B-I and LC3B-II, and a similar effect was observed following treatment with rapamycin, an autophagy inducer. Our findings provide experimental evidence for new potential autophagy modulators in the hallucinogenic poisonous mushroom G. orientispectabilis.

Bipoladien A, a Sesterterpenoid Containing an Undescribed 5/8/5/7 Carbon Skeleton from Bipolaris maydis.

Bipoladiens A-E (1-5), five new ophiobolin-derived sesterterpenoids, and a known compound 6 (bipolaricin R) were isolated from the cultures of the phytopathogenic fungus Bipolaris maydis. Their structures and absolute configurations were elucidated based on comprehensive spectroscopic analyses, HRESIMS, electronic circular dichroism (ECD) calculations, and single-crystal X-ray diffraction analyses. Notably, compound 1 has an undescribed tetracyclic 5/8/5/7 fused carbon skeleton, and compound 2 possesses a rare multicyclic caged ring system. The biosynthetic pathway of 1 was proposed starting from 6 via a series of oxidation and cyclization reactions. Compound 6 showed excellent antiproliferation and apoptosis induction effects against A549 cell line. Additionally, compounds 5 and 6 exhibited noticeable antimicrobial ability against Bacillus cereus, Staphylococcus aureus, and Staphylococcus epidermidis. These findings not only developed the chemical and bioactivities diversities of ophiobolin-sesterterpenoid but also provided an idea to boost the application of natural products in the control of food pathogens.

Penigrines A-E: Five undescribed azepine-indole alkaloids from Penicillium griseofulvum.

Penigrines A-E (1-5), five undescribed azepine-indole alkaloids, were isolated from the fungus Penicillium griseofulvum. Their structures with absolute configurations were determined by NMR, HRESIMS, ECD calculation, and X-ray diffraction experiments. Penigrine C (3) possesses an undescribed 6-oxa-8-azabicyclo[3.2.2]nonane-7,9-dione moiety that fused to an indole core, and penigrines D and E (4 and 5) are a pair of epimers. The plausible biosynthetic pathways of 1-5 are proposed. Penigrine A (1) shows the potential for heart failure treatment.

Structurally Diverse Coumarins from Peucedanum praeruptorum and their Anti-Inflammatory Activities via NF-κB Signaling Pathway.

The phytochemical study of Peucedanum praeruptorum led to the isolation of twenty-five coumarins (1-25). Of which, (±) praeruptol A (±1), one pair of previous undescribed seco-coumarin enantiomers were obtained. Their structures were established according to HR-ESI-MS, NMR, X-ray single crystal diffraction analysis, as well as ECD calculation. All compounds were tested for anti-inflammatory activity in the RAW264.7 macrophage model, and eight compounds (7-10, and 13-16) exhibited significant inhibitory effects with IC50 values ranging from 9.48 to 34.66 µM. Among them, compound 7 showed the strongest inhibitory effect, which significantly suppressed the production of IL-6, IL-1ß, and TNF-α, as well as iNOS and COX-2 in a concentration-dependent manner. Further investigated results showed that compound 7 exerted an anti-inflammatory effect via the NF-κB signaling pathway.

Limonoids and alkaloids from Tetradium austrosinense (Hand.-Mazz.) T.G.Hartley.

A pair of new enantiomeric indolopyridoquinazoline-type alkaloids, (+)-1,7S,8R- and (-)-1,7R,8S-trihydroxyrutaecarpine (3a and 3b), and a new limonoid-tyrosamine hybrid, austrosinin (8), along with six known alkaloids and limonoids, were isolated from the stems with leaves of Tetradium austrosinense. Their structures were elucidated on the basis of analysis of MS, NMR, ECD and time-dependent density functional theory-based electronic circular dichroism (TDDFT-ECD) calculations, as well as proposed biosynthetic pathway. An anti-inflammatory bioassay in vitro showed 8 had significant immunosuppressive effect against the production of pro-inflammatory cytokine TNF-α in lipopolysaccharide (LPS)-stimulated RAW264.7 cells.

Caffeoylquinic acids protect against alcoholic liver injury and rare C10 acetylenic acids from Erigeron breviscapus.

Three new compounds (1-2, 4) along with ten known ones (3, 5-13), were isolated from the whole plant of Erigeron breviscapus. Compounds 1 and 2, two novel C10 acetylenic acids and compound 4, a jasmone glucoside were elucidated by the detailed analysis of 1D and 2D NMR, HRESIMS spectra, and experimental and calculated electronic circular dichroism (ECD). Compounds 1-3 represent the first example of acetylenic acids incorporating C10 skeleton from E. breviscapus. In addition, the antioxidant effects of all compounds were evaluated by ferric reducing power, 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate acid) (ABTS) and 2.2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assays. Our results indicated the significant antioxidant activity of caffeoylquinic acids. Additionally, compounds 10-11 and 13 played protective role on alcoholic liver injury cells in a dose-dependent manner.

Fungal polyketides produced by an endophytic fungus Phoma sp. associated with Gastrodia elata.

Two novel fungal polyketides, phometides A (1) and B (2), together with four known compounds (3-6), were isolated from the endophytic fungus Phoma sp. YUD17001 obtained from Gastrodia elata Blume. The structures were elucidated based on spectroscopic analyses, X-ray crystal diffraction, and time-dependent density functional theory/electronic circular dichroism (TDDFT/ECD) calculations. Structurally, phometide A (1) represented the first example of C12 polyketide characterized by an unusual tetrahydrobenzofuran-3(2H)-one core with an α,ß-unsaturated ketone functionality, while phometide B (2) was an unprecedented molecule containing a 2-pentylcycloheptan-1-one scaffold. In an antimicrobial activity assay, phometide A (1) exhibited significant inhibitory activity against Staphylococcus aureus with MIC value of 4 µg/mL. Phometide B (2) showed moderate antifungal activity against Candida albicans with an MIC value of 16 µg/mL. Furthermore, compounds 1 and 2 were evaluated for their acetylcholinesterase inhibitory and cytotoxic activities.

Lignan glucosides from Gentiana macrophylla with potential anti-arthritis and hepatoprotective activities.

Ten lignans, including six previously undescribed phenolic ester glycosyl lignans (1-6), were isolated from a well-known traditional Chinese medicine, Qin-Jiao, which is the dry root of Gentiana macrophylla Pall. (Gentianaceae). Their structures were determined by spectroscopic and chemical methods, especially 2D NMR techniques. Quantum chemical calculations of theoretical ECD spectra allowed the determination of their absolute configurations. Refer to its traditional applications for the treatment of rheumatic arthralgia and hepatopathy, these compounds were evaluated on a TNF-α induced MH7A human synoviocyte inflammation model and a D-GalN induced AML12 hepatocyte injury model. Compounds 1, 2, 5, and 6 significantly reduced the release of proinflammatory cytokine IL-1ß in MH7A cells at 15 µM and they also could strongly protect AML12 cells against D-GalN injury at 30 µM. Flow cytometry and Western blot analysis showed that compound 5 ameliorated D-GalN induced AML12 cell apoptosis by upregulating the expression of anti-apoptotic Bcl-2 protein and down-regulating the expression of pro-apoptotic Bax protein.

Terpenoids from the Roots of Stellera chamaejasme (L.) and Their Bioactivities.

An undescribed diterpene, stellerterpenoid A (1), and two undescribed sesquiterpenoids, stellerterpenoids B and C (2-3), together with six known compounds, prostratin (4) stelleraguaianone B (5), chamaejasnoid A (6), auranticanol L (7), wikstronone C (8), and oleodaphnone (9), were isolated from the roots of Stellera chamaejasme L. Their structures were elucidated by extensive spectroscopic data (1D, 2D NMR, IR, UV, and HR-ESI-MS). The absolute configuration of 1-3 was elucidated based on ECD calculation. Among them, stellerterpenoid A was a rare 13, 14-seco nortigliane diterpenoid and stellerterpenoid B was a guaiacane-type sesquiterpenoid with an unusual 1, 2-diketone moiety. The known stelleraguaianone B (5) exhibited moderate activity for suppressing NO production in lipopolysaccharide (LPS)-treated RAW 264.7 macrophages cells with an IC50 value of 24.76 ± 0.4 µM. None of the compounds showed anti-influenza virus or anti-tumor activity in vitro.

Hosimosines A-E, structurally diverse cytisine derivatives from the seeds of Ormosia hosiei Hemsl. et Wils.

Ormosia hosiei Hemsl. et Wils (Fabaceae family) is an arbor species endemic to China. The seeds of O. hosiei have been used as traditional Chinese medicine to treat hernia, abdominal pain, blood stasis and amenorrhea. Cytisine-like and angustifoline type alkaloids were main components identified from this plant. In our research on the bioactive alkaloids from the promising Chinese medicinal plants, four new angustifoline type alkaloids (1-4) and a new cytisine-like alkaloid (5), named hosimosine A-E, together with 13 known analogues (6-18) were isolated from the seeds of O. hosiei. Their structures were elucidated by the extensive spectroscopic methods, especially the interpretation of NMR spectra and specific rotations, along with the methods of NMR and ECD calculation. Compounds 1-4 were identified as two pairs of epimers, whose relative configurations were deduced from density functional theory (DFT) calculations of NMR chemical shifts and DP4+ analysis, and absolute configurations were determined by comparison of their experimental and theoretical ECD spectra. Compound 5 displayed two sets of NMR data caused by the existence of tautomeric forms. Compounds 14, 17 and 18 were determined to be enantiomers of literature compounds. Some of the isolates exhibited moderate cytotoxic effects against HepG2, A2780 and MCF-7 cells.

Japonins A-D, cyathane diterpenoids with neurite outgrowth-promoting activity isolated from Onychium japonicum using NMR and MS/MS-based molecular networking.

Guided by MS/MS-based molecular networking strategy, four new cyathane diterpenoids japonin A-D (1-4), together with the known analogues (5 and 6), have been isolated from aerial parts of Onychium japonicum. The structures of the new compounds were elucidated through a combination of NMR and MS experiments. Through single-crystal X-ray diffraction analysis, and comparison of experimental and calculated computational electronic circular dichroism (ECD) spectra, the absolute configurations of compounds 1-4 were determined. The new compound 1 showed promoting effects on the differentiation of PC12 at a concentration of 40 µM.

Sesquiterpene lactones from Artemisia verlotorum and their anti-inflammatory activities.

Seven new sesquiterpenoids (1-7) and 19 known analogues were isolated from the whole plant of Artemisia verlotorum. Their structures were determined by extensive analysis of 1D and 2D NMR and HRESIMS data, electronic circular dichroism (ECD) spectra, density functional theory (DFT) NMR calculations, and time dependent density functional theory (TDDFT) ECD calculations. The absolute configurations of 1, 3, 5 and 7 were confirmed by single crystal X-ray diffraction experiments. Compounds 1 and 2 possess a rarely reported 5/8-bicyclic skeleton, while both compounds 3 and 4 were uncommon iphionane-type sesquiterpenoids. Eudesmane sesquiterpenoids (5-17) reported in this study are all 7,8-cis-lactones, of which, compound 7 represents the first eudesmane sesquiterpene with an oxygen bridge connecting C-5 and C-11. All the compounds were tested in vitro for their anti-inflammatory activities in LPS-stimulated RAW 264.7 murine macrophages. Compound 18 showed a potent inhibitory effect on NO production, with IC50 values of 3.08 ± 0.61 µM.

Hyposterolactone A, a 3α-Hydroxy Steroidal Lactone from the Deep-Sea-Derived Fungus Hypocrea sp. ZEN14.

Chemical investigation of the deep-sea-derived fungus Hypocrea sp. ZEN14 afforded a new 3α-hydroxy steroidal lactone, hyposterolactone A (1) and 25 known secondary metabolites (2-26). The structure of the new compound was established by detailed spectroscopic analysis, electronic circular dichroism (ECD) calculation as well as a J-based configuration analysis. Compound 10 showed potent cytotoxicity against Huh7 and Jurkat cells with IC50 values of 1.4 µM and 6.7 µM, respectively.

New Glycerolipids from the Traditional Chinese Medicine of Syngnathus acus (Hai-Long).

Two new glycerolipids, syngaculipids A and B (1 and 2), one first naturally occurring metabolite (8), together with five known compounds (3-7) were isolated from the AcOEt fraction of Syngnathus acus L. (Hai-Long). Their structures were elucidated by comprehensive spectral analyses involving UV, IR, MS, 1D and 2D NMR spectra and ECD calculations. All the isolated compounds were evaluated for their cytotoxicity against A549 and HCT-116 cell lines. Compound 8 exhibited moderate cytotoxicity with IC50 values of 34.5 and 38.9 µM on the A549 and HCT-116 cell lines, respectively.