Abietane diterpenoids and iridoids from Caryopteris mongolica / 中国天然药物

Six new abietane diterpenoids (1-6) and five undescribed iridoids (7-11) have been isolated from the aerial parts of Caryopteris mongolica. The intricate structural characterization of these compounds was meticulously undertaken using an array of advanced spectroscopic techniques. This process was further enhanced by the application of DP4+ probability analyses and electronic circular dichroism (ECD) calculations. Following isolation and structural elucidation, the cytotoxicity of these compounds was evaluated. Among them, compound 3 stood out, displaying significant cytotoxic activity against HeLa cells with an IC50 value of 7.83 ± 1.28 μmol·L-1. Additionally, compounds 1, 2, 4, 9, and 10 manifested moderate cytotoxic effects on specific cell lines, with IC50 values ranging from 11.7 to 20.9 μmol·L-1.

Artemdubinoids A-N: novel sesquiterpenoids with antihepatoma cytotoxicity from Artemisia dubia / 中国天然药物

In pursuit of effective agents for hepatocellular carcinoma derived from the Artemisia species, this study built upon initial findings that an ethanol (EtOH) extract and ethyl acetate (EtOAc) fraction of the aerial parts of Artemisia dubia Wall. ex Bess. exhibited cytotoxicity against HepG2 cells with inhibitory rates of 57.1% and 84.2% (100 μg·mL-1), respectively. Guided by bioactivity, fourteen previously unidentified sesquiterpenes, artemdubinoids A-N (1-14), were isolated from the EtOAc fraction. Their structural elucidation was achieved through comprehensive spectroscopic analyses and corroborated by the comparison between the experimental and calculated ECD spectra. Single crystal X-ray diffraction provided definitive structure confirmation for artemdubinoids A, D, F, and H. Artemdubinoids A and B (1-2) represented unique sesquiterpenes featuring a 6/5-fused bicyclic carbon scaffold, and their putative biosynthetic pathways were discussed; artemdubinoid C (3) was a novel guaianolide derivative that might be formed by the [4 + 2] Diels-Alder reaction; artemdubinoids D and E (4-5) were rare 1,10-seco-guaianolides; artemdubinoids F-K (6-11) were chlorine-containing guaianolides. Eleven compounds exhibited cytotoxicity against three human hepatoma cell lines (HepG2, Huh7, and SK-Hep-1) with half-maximal inhibitory concentration (IC50) values spanning 7.5-82.5 μmol·L-1. Artemdubinoid M (13) exhibited the most active cytotoxicity with IC50 values of 14.5, 7.5 and 8.9 μmol·L-1 against the HepG2, Huh7, and SK-Hep-1 cell lines, respectively, which were equivalent to the positive control, sorafenib.

Asponchimides A-E: new enantiomeric N-acetyldopamine trimers from Aspongopus chinensis / 中国天然药物

Five new racemic N-acetyldopamine (NADA) trimers, asponchimides A-E (1-5), were isolated from Aspongopus chinensis, a prominent traditional Chinese medicinal insect employed for alleviating pain, treating indigestion, and addressing kidney ailments. Compounds 1-5 were successfully resolved by chiral high-performance liquid chromatography (HPLC), yielding five pairs of enantiomers: (+)- and (-)-asponchimides A-E (1a/1b-5a/5b). Their structural identities were discerned by extensive spectroscopic analyses, including high-resolution mass spectrometry (HRMS), ultraviolet-visible (UV-Vis) spectroscopy, infrared (IR) spectroscopy, and nuclear magnetic resonance (NMR), and their absolute configurations were determined by electronic circular dichroism (ECD) calculations. Compounds 1-5 are pioneering instances of NADA trimers featuring a Δ7 double bond. When subjected to a series of bioassays, a majority of the compounds exhibited weak inhibitory activity against nitric oxide (NO) production in LPS-induced RAW 264.7 cells.

Six new coumarins from the roots of Toddalia asiatica and their anti-inflammatory activities / 中国天然药物

We reported the discovery of six novel coumarins, toddasirins A-F (1-6), each endowed with modified isoprenyl or geranyl side chains, derived from the roots of Toddalia asiatica. Comprehensive structural elucidation was achieved through multispectroscopic analyses, single-crystal X-ray diffraction experiments, and advanced quantum mechanical electronic circular dichroism (ECD) calculations. Furthermore, the anti-inflammatory activity of these compounds was assessed. Notably, compounds 1-3 and 6 demonstrated notable inhibitory effects on nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 cells, with 50% inhibitory concentration (IC50) values of 3.22, 4.78, 8.90, and 4.31 μmol·L-1, respectively.

Chemical constituents from Salacia polysperma / 中国中药杂志

Nine compounds were isolated from the 90% ethanol extract of Salacia polysperma by silica gel, Sephadex LH-20 column chromatography, together with preparative HPLC methods. Based on HR-ESI-MS, MS, 1D and 2D NMR spectral analyses, the structures of the nine compounds were identified as 28-hydroxy wilforlide B(1), wilforlide A(2), 1β,3β-dihydroxyurs-9(11),12-diene(3),(-)-epicatechin(4),(+)-catechin(5),(-)-4'-O-methyl-ent-galloepicatechin(6), 3-hydroxy-1-(4-hydroxy-3-methoxy-phenyl)propan-1-one(7),(-)-(7S,8R)-4-hydroxy-3,3',5'-trimethoxy-8',9'-dinor-8,4'-oxyneoligna-7,9-diol-7'-aldehyde(8), and vanillic acid(9). Compound 1 is a new oleanane-type triterpene lactone. Compounds 1, 3, 4, 7-9 were isolated from the Salacia genus for the first time. All compounds were assayed for their α-glucosidase inhibitory activity. The results suggested that compound 8 exhibited moderate α-glucosidase inhibitory activity, with an IC_(50) value of 37.2 μmol·L~(-1), and the other compounds showed no α-glucosidase inhibitory activity.

Chemical constituents of Helleborus thibetanus / 中国中药杂志

The chemical constituents of Helleborus thibetanus were isolated and purified by silica gel column chromatography, Sephadex LH-20 gel column chromatography, and semi-preparative RP-HPLC, and the structures of all compounds were identified by modern spectrographic technology(MS, NMR). The MTT method was used to measure the cytotoxicity of compounds 1-8. Twelve compounds were isolated from the roots and rhizomes of H. thibetanus and were identified as(25R)-22β,25-expoxy-26-[(O-β-D-glucopyranosyl)oxy]-1β,3β-dihydroxyfurosta-5-en(1), β-sitosterol myristate(2), β-sitosterol lactate(3), β-sitosterol 3-O-β-D-glucopyrannoside(4), 4,6,8-trihydroxy-3,4-dihydronaphthalen-1(2H)-one(5), 1,3,5-trimethoxybenzene(6), 7,8-dimethylbenzo pteridine-2,4(1H,3H)-dione(7), 1H-indole-3-carboxylic acid(8), p-hydroxy cinnamic acid(9), lauric acid(10), n-butyl α-L-arabinofuranoside(11) and methyl-α-D-fructofuranoside(12), respectively. Among them, compound 1 is a new compound and named thibetanoside L; compounds 2, 5-8, 11 are first isolated from the family Ranunculaceae; compound 12 is isolated from the genus Helleborus for the first time. The results of MTT assay showed that the IC_(50) values of compounds 1-8 against HepG2 and HCT116 cells were greater than 100 μmol·L~(-1).

Two new sesquiterpenes in Qi-nan Aquilariae Lignum Resinatum / 中国中药杂志

This study aimed to investigate the chemical constituents of supercritical extract from Qi-nan Aquilariae Lignum Resinatum by silica gel column chromatography, thin-layer chromatography, and semi-preparative high-performance liquid chromatography. One new elemane-type and one new eudesmane-type sesquiterpene compounds were isolated from the extract, and their structures were identified by MS, UV, IR, NMR, and ECD spectroscopic techniques, and named aquqinanol C(1) and aquqinanol D(2). Both compounds are novel compounds. The neuroprotective effect of the compounds on CORT-induced PC12 cell damage was determined in vitro. The results showed that compounds 1 and 2 exhibited a certain protective effect against CORT-induced damage in PC12 cells.

A new allo-aromadendrane sesquiterpene from Dendrobium nobile / 中国中药杂志

To study the chemical constituents in the non-alkaloid part of stems of Dendrobium nobile. The macroporous adsorption resin, MCI, silica gel, RP-C_(18), and Sephadex LH-20 gel, preparative thin layer chromatography, and preparative high-performance liquid chromatography(HPLC) were used to isolate and purify the compounds. The structures of the compound were determined according to the spectra data, physicochemical properties, and relevant references. A total of 8 compounds were isolated from D. nobile, which were soltorvum F(1), p-hydroxyphenylpropionic acid(2), vanillic acid(3), p-hydroxybenzoic acid(4), N-trans-cinnamic acid acyl-p-hydroxybenzene ethylamine(5),(+)-(1R,2S,3R,4S,5R,6S,9R)-2,11,12-trihydroxypicrotoxane-3(15)-lactone(6), dendronobilin H(7), soltorvum E(8). Compound 1 was a novel compound, named as soltorvum F. Compound 8 was isolated from Dendrobium species for the first time.

A new xanthone from hulls of Garcinia mangostana and its cytotoxic activity / 中国中药杂志

Eight compounds were isolated from ethyl acetate fraction of 80% ethanol extract of the hulls of Garcinia mangostana by silica gel, Sephadex LH-20 column chromatography, as well as prep-HPLC methods. By HR-ESI-MS, MS, 1D and 2D NMR spectral analyses, the structures of the eight compounds were identified as 16-en mangostenone E(1), α-mangostin(2), 1,7-dihydroxy-2-(3-methy-lbut-2-enyl)-3-methoxyxanthone(3), cratoxyxanthone(4), 2,6-dimethoxy-para-benzoquinone(5), methyl orselinate(6), ficusol(7), and 4-(4-carboxy-2-methoxyphenoxy)-3,5-dimethoxybenzoic acid(8). Compound 1 was a new xanthone, and compound 4 was a xanthone dimer, compound 5 was a naphthoquinone. All compounds were isolated from this plant for the first time except compounds 2 and 3. Cytotoxic bioassay suggested that compounds 1, 2 and 4 possessed moderate cytotoxicity, suppressing HeLa cell line with IC_(50) va-lues of 24.3, 35.5 and 17.1 μmol·L~(-1), respectively. Compound 4 also could suppress K562 cells with an IC_(50) value of 39.8 μmol·L~(-1).

Research progress on natural guaiane-type sesquiterpenoids and their biological activities / 中国中药杂志

Guaiane-type sesquiterpenoids are a class of terpenoids with [5,7] ring-fused system as the basic skeletal structure composed of three isoprene units, which are substituted by 4,10-dimethyl-7-isopropyl. According to the difference in functional groups and degree of polymerization, they can be divided into simple guaiane-type sesquiterpenoids, sesquiterpene lactones, sesquiterpene dimers, and sesquiterpene trimers. Natural guaiane-type sesquiterpenoids are widely distributed in plants, fungi, and marine organisms, especially in families such as Compositae, Zingiberaceae, Thymelaeaceae, Lamiaceae, and Alismataceae. Guaiane-type sesquiterpenoids have good antibacterial, anti-inflammatory, anticancer, and neuroprotective effects. In this paper, the novel guaiane-type sesquiterpenoids isolated and identified in recent 10 years(2013-2022) and their biological activities were reviewed in order to provide refe-rences for the research and development of guaiane-type sesquiterpenoids.

Research progress in tigliane-type macrocyclic diterpenoids / 中国中药杂志

Tigliane type macrocyclic diterpenoids with special structures and diverse bioactivities are mainly extracted from plants of Euphorbiaceae and Thymelaeaceae. According to the different functional groups, they can be classified into types of phorbol esters, C-4 deoxyphorbol esters, C-12 deoxyphorbol esters, C-16 or C-17 substituted phorbol esters and others. Most of them present promising antiviral activities and cytotoxic activities and are expected to be developed as candidates for anti-AIDS, anti-tuberculosis, and anti-tumor clinical trials, demonstrating great potential for the application in healthcare. This paper reviews 115 novel tigliane-type diterpenoids discovered since 2013 and summarize their chemical structures and bioactivities, aiming to lay a foundation for further development and utilization of these compounds and provide new ideas for the development of clinical drugs.

New steroidal saponins from aerial parts of Paris polyphylla var. chinensis / 中国中药杂志

The shortage of Paridis Rhizoma promotes comprehensive utilization and development research of waste aerial parts of the original plant. The chemical compositions of the aerial parts of Paris polyphylla var. chinensis were clarified based on the ultrahigh performance liquid chromatography tandem quadrupoles time of flight mass spectrometry(UPLC-QTOF-MS/MS) in the previous investigation, and a series of flavonoids and steroidal saponins were isolated. The present study continued the isolation and structure identification of the new potential compounds discovered based on UPLC-QTOF-MS/MS. By using silica gel, ODS, flash rapid preparation, and other column chromatography techniques, combined with prepared high performance liquid chromatography, five compounds were isolated from the 75% ethanol extract of the aerial parts of P. polyphylla var. chinensis, and their structures were identified by spectral data combined with chemical transformations, respectively, as(23S,25R)-23,27-dihydroxy-diosgenin-3-O-α-L-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranoside(1),(25R)-26-O-β-D-glucopyranosyl-furost-5-en-3β,22α,26-triol-3-O-α-L-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→4)]-β-D-glucopyranoside(2),(25R)-27-O-β-D-glucopyranosyl-5-en-3β,27-dihydroxyspirost-3-O-α-L-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→4)]-β-D-glucopyranoside(3),(25R)-27-O-β-D-glucopyranosyl-5-en-3β,27-dihydroxyspirost-3-O-α-L-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranoside(4), and aculeatiside A(5). Among them, compounds 1-4 were new ones, and compound 5 was isolated from P. polyphylla var. chinensis for the first time.

A new cinnamic acid ester derivative from Liquidambaris Resina / 中国中药杂志

Twelve compounds were isolated from Liquidambaris Resina by silica gel column chromatography and thin layer chromatography. Their structures were identified on the basis of spectral data, electron capture detector data, and physicochemical properties as(2'R, 3'R)-2',3'-dihydroxy-hydrocinnamyl-(E)-cinnamate(1),(E)-cinnamyl-(E)-cinnamate(2), cinnamic acid(3), 28-norlup-20(29)-en-3-one-17β-hydroperoxide(4), erythrodiol(5), 13β,28-epoxy-30-hydroxyolean-1-en-3-one(6),(3β)-olean-12-ene-3,23-diol(7), 2α,3α-dihydroxy-olean-12-en-28-oic acid(8), 28-hydroxyolean-12-en-3-one(9), 3-epi-oleanolic acid(10), 3-oxo-oleanolic acid(11), and hederagenin(12). Compound 1 was a new cinnamic acid ester derivative and compounds 2-4,6-8, and 12 were isolated from Liquidambaris Resina for the first time. Compounds 4, 5, 10, and 12 exerted inhibitory effects on the proliferation of human umbilical vein endothelial cells(HUVEC) with the IC_(50) values of(17.43±2.17),(35.32±0.61),(27.50±0.80), and(46.30±0.30) μmol·L~(-1), respectively.

Anti-inflammatory sesquiterpene polyol esters from the stem and branch of Tripterygium wilfordii / 中国天然药物

The stem and branch extract of Tripterygium wilfordii (Celastraceae) afforded seven new dihydroagarofuran sesquiterpene polyesters [tripterysines A-G (1-7)] and eight known ones (8-15). The chemical structures of these new compounds were established based on combinational analysis of HR-ESI-MS and NMR techniques. The absolute configurations of tripterysines A-C (1-3) and E-G (5-7) were determined by X-ray crystallographic analysis and circular dichroism spectra. All the compounds were screened for their inhibitory effect on inflammation through determining their inhibitory effect on nitric oxide production in LPS-induced RAW 264.7 cells and the secretion of inflammatory cytokines TNF-α and IL-6 in LPS-induced BV2 macrophages. Compound 9 exhibited significant inhibitory activity on NO production with an IC50 value of 8.77 μmol·L-1. Moreover, compound 7 showed the strongest inhibitory effect with the secretion of IL-6 at 27.36%.

Five new spirosterol saponins from Allii Macrostemonis Bulbus / 中国天然药物

Five new spirostanol saponins (1-5) and seven known compounds (6-12) were isolated from the n-butanol fraction of 75% ethanol extract of Allii Macrostemonis Bulbus. The identification and structural elucidation of all the isolates were performed through extensive 1D and 2D NMR experiments, HR-ESI-MS data analysis and comparisons with literature values. Antioxidant evaluation showed that compounds 6-11 exhibited certain scavenging effects on ABTS radical, where compounds 6, 7 and 11 had IC50 values of 0.208, 0.057 and 0.014 mg·mL-1, respectively.

Seven drimane-type sesquiterpenoids from an earwig-associated Aspergillus sp / 中国天然药物

Drimane-type sesquiterpenoids are widely distributed in fungi. From the ethyl acetate extract of the earwig-derived Aspergillus sp. NF2396, seven new drimane-type sesquiterpenoids, named drimanenoids A-G (1-7), were isolated. Their structures were elucidated by diverse spectroscopic analysis including high-resolution ESI-MS, one- and two-dimensional NMR spectroscopy. Drimanenoids A-F (1-6) are new members of drimane-type sesquiterpenoid esterified with unsaturated fatty acid side chain at C-6. Drimanenoids C (3), D (4) and F (6) showed antibacterial activity against five types of bacteria with different inhibition diameters. Drimanenoid D (4) exhibited moderate cytotoxicity against human myelogenous leukemia cell line K562 with an IC50 value of 12.88 ± 0.11 μmol·L-1.

Chemical constituents of diterpenoids from Boswellia carterii / 中国中药杂志

This paper explored the chemical constituents of Boswellia carterii by column chromatography on silica gel, Sephadex LH-20, ODS column chromatography, and semi-preparative HPLC. The structures of the compounds were identified by physicochemical properties and spectroscopic data such as infrared radiation(IR), ultra violet(UV), mass spectrometry(MS), and nuclear magnetic resonance(NMR). Seven diterpenoids were isolated and purified from n-hexane of B. carterii. The isolates were identified as(1S,3E,7E,11R,12R)-11-hydroxy-1-isopropyl-4,8,12-trimethyl-15-oxabicyclo[10.2.1]pentadeca-3,7-dien-5-one(1),(1R,3S,4R,7E,11E)-4,8,12,15,15-pentamethyl-14-oxabicyclo[11.2.1]hexadeca-7,11-dien-4-ol(2), incensole(3),(-)-(R)-nephthenol(4), euphraticanoid F(5), dilospirane B(6), and dictyotin C(7). Among them, compounds 1 and 2 were new and their absolute configurations were determined by comparison of the calculated and experimental electronic circular dichroisms(ECDs). Compounds 6 and 7 were obtained from B. carterii for the first time.

New di-spirocyclic labdane diterpenoids from the aerial parts of Leonurus japonicus / 中国天然药物

Phytochemical investigation on the ethanol extract of a well-known medicinal herb Leonurus japonicus, led to the separation of 18 labdane type diterpenoids (1-18). Through comprehensive spectroscopic analyses and quantum chemical calculations, these compounds were structurally characterized as six new interesting 5,5,5-di-spirocyclic ones (1-6), two new (7 and 8) and six known (13-18) interesting 6,5,5-di-spirocyclic ones, a new rare 14,15-dinor derivative (9), and three new ones incorporating a γ-lactone unit (10-12). An in vitro neuroprotective assay in RSC96 cells revealed that compounds 7 and 12 exhibited neuroprotective activity in a concentration-dependent way, comparable to the reference drug N-acetylcysteine.

Bioassay-guided isolation of α-Glucosidase inhibitory constituents from Hypericum sampsonii / 中国天然药物

This study employed the α-glucosidase inhibitory activity model as an anti-diabetic assay and implemented a bioactivity-guided isolation strategy to identify novel natural compounds with potential therapeutic properties. Hypericum sampsoniiwas investigated, leading to the isolation of two highly modified seco-polycyclic polyprenylated acylphloroglucinols (PPAPs) (1 and 2), eight phenolic derivatives (3-10), and four terpene derivatives (11-14). The structures of compounds 1 and 2, featuring an unprecedented octahydro-2H-chromen-2-one ring system, were fully characterized using extensive spectroscopic data and quantum chemistry calculations. Six compounds (1, 5-7, 9, and 14) exhibited potential inhibitory effects against α-glucosidase, with IC50 values ranging from 0.050 ± 0.0016 to 366.70 ± 11.08 μg·mL-1. Notably, compound 5 (0.050 ± 0.0016 μg·mL-1) was identified as the most potential α-glucosidase inhibitor, with an inhibitory effect about 6900 times stronger than the positive control, acarbose (IC50 = 346.63 ± 15.65 μg·mL-1). A docking study was conducted to predict molecular interactions between two compounds (1 and 5) and α-glucosidase, and the hypothetical biosynthetic pathways of the two unprecedented seco-PPAPs were proposed.

Five new terpenoids from Viburnum odoratissimum var. sessiliflorum / 中国天然药物

Five new terpenoids, including two vibsane-type diterpenoids (1, 2) and three iridoid allosides (3-5), together with eight known ones, were isolated from the leaves and twigs of Viburnum odoratissimum var.sessiliflorum. Their planar structures and relative configurations were determined by spectroscopic methods, especially 2D NMR techniques. The sugar moieties of the iridoids were confirmed as β-D-allose by GC analysis after acid hydrolysis and acetylation. The absolute configurations of neovibsanin Q (1) and dehydrovibsanol B (2) were determined by quantum chemical calculation of their theoretical electronic circular dichroism (ECD) spectra and Rh2(OCOCF3)4-induced ECD analysis. The anti-inflammatory activities of compounds 1, 3, 4, and 5 were evaluated using an LPS-induced RAW264.7 cell model. Compounds 3suppressed the release of NO in a dose-dependent manner, with an IC50 value of 55.64 μmol·L-1. The cytotoxicities of compounds 1-5 on HCT-116 cells were assessed and the results showed that compounds 2 and 3 exhibited moderate inhibitory activities with IC50 values of 13.8 and 12.3 μmol·L-1, respectively.