Three new antinociceptive diterpenoids from the fruits of Rhododendron molle.

Investigation of the fruits of Rhododendron molle G. Don led to the isolation of three new grayanane-type diterpenoids, rhodomolleins LIV-LVI (1-3). The structures and absolute configurations of new compounds were fully elucidated by spectroscopic analysis and single-crystal X-ray diffraction, including HRESIMS, 1 D and 2 D NMR data. Compounds 1-3 were evaluated for analgesic activities utilizing an acetic acid-induced writhing test in mice. Compound 1 showed a significant antinociceptive effect with writhe inhibition rates of 72.9% and 100% at doses of 6 mg/kg and 20 mg/kg in mice, respectively. The binding mode of 1 to N-ethylmaleimide-sensitive factor (NSF, PDB: 6IP2) was explored by molecular docking, indicating the presence of hydrogen bond interactions which account for its analgesic activity.

Pseudoamaolide P, a 1,2:3,4:9,10:9,19-tetraseco-cycloartane triterpene spiroketal lactone from seeds of Pseudolarix amabilis.

A 1,2:3,4:9,10:9,19-tetraseco-cycloartane triterpene spiroketal lactone, pseudoamaolide P (1), two new labdane-type diterpenoids, pseudoamains A and B (2-3), and four known cembrane-type diterpenoids (4-7) were isolated from the seeds of Pseudolarix amabilis. The structures of these compounds were elucidated by spectroscopic analyses, including HRESIMS, 1D-, and 2D-NMR. The anti-inflammatory activities of the compounds were evaluated by suppressing the transcription of the NF-κB-dependent reporter gene in LPS-induced 293 T/NF-κB-luc cells. All compounds do not show potent activity.

Cadinane sesquiterpenes from the stems and branches of Illicium ternstroemioides.

Three new cadinane sesquiterpenes (1-3) and three known sesquiterpenes were isolated from the stems and branches of Illicium ternstroemioides A. C. Smith. The structures of the new compounds were elucidated by extensive analysis of spectroscopic and HRESIMS data. The structures of illiternins A-C (1-3) were confirmed by single crystal X-ray diffraction, allowing for the determination of their absolute configurations. Compounds 3 and 6 exhibited antiviral activity against Coxsackievirus B3 with IC50 values of 33.3 and 57.7 µM, respectively.

Diverse prenylated C6-C3 derivatives from the stems and branches of Illicium ternstroemioides A. C. Smith with anti-inflammatory and antiviral activities.

Fifteen unreported prenylated C6-C3 derivatives (1-15) were isolated from the stems and branches of Illicium ternstroemioides A. C. Smith, including one bis-prenylated C6-C3 derivative (1), three prenylated C6-C3 derivative-shikimic acid ester hybrids (2-4) and 11 prenylated C6-C3 monomers (5-15). The structures of compounds 1-15 were elucidated by spectroscopic analysis (UV, IR, 1D and 2D NMR, and HRESIMS). The absolute configurations of the compounds were determined using electronic circular dichroism (ECD), induced circular dichroism (ICD), and the modified Mosher's method. Among the isolates, compounds 11, 12, and 15 exhibited significant anti-inflammatory activities by inhibiting the nitric oxide with IC50 values ranging from 1.89 to 24.83 µM in lipopolysaccharide-stimulated murine RAW 264.7 macrophages and murine BV2 microglial cells; compounds 2, 3, and 7 exhibited antiviral activitives against Coxsackievirus B3 with an IC50 value of 33.3, 25.9, and 27.8 µM, respectively.

Dianthrone derivatives from Polygonum multiflorum Thunb: Anti-diabetic activity, structure-activity relationships (SARs), and mode of action.

PTP1B plays an important role as a key negative regulator of tyrosine phosphorylation associated with insulin receptor signaling in the therapy for diabetes and obesity. In this study, the anti-diabetic activity of dianthrone derivatives from Polygonum multiflorum Thunb., as well as the structure-activity relationships, mechanism, and molecular docking were explored. Among these analogs, trans-emodin dianthrone (compound 1) enhances insulin sensitivity by upregulating the insulin signaling pathway in HepG2 cells and displays considerable anti-diabetic activity in db/db mice. By using photoaffinity labeling and mass spectrometry-based proteomics, we discovered that trans-emodin dianthrone (compound 1) may bind to PTP1B allosteric pocket at helix α6/α7, which provides fresh insight into the identification of novel anti-diabetic agents.

Bergamotane-type sesquiterpenes from the leaves and twigs of Illicium oligandrum and their anti-inflammatory activities.

Eight undescribed ß-bergamotene-type sesquiterpene oliganins A-H (1-8) and one known α-bergamotene-type sesquiterpene (9) were isolated from the leaves and twigs of Illicium oligandrum Merr. & Chun. The structures of compounds 1-8 were elucidated by extensive spectroscopic data, and the absolute configurations were determined by using a modified Mosher's method and electronic circular dichroism calculations. The isolates were further evaluated in terms of their anti-inflammatory potential on nitric oxide (NO) generation in lipopolysaccharide-stimulated RAW264.7 and BV2 cells. Compounds 2 and 8 exhibited potent inhibitory effects on the production of NO with IC50 values ranging from 21.65 to 49.28 µM, which were greater than or comparable to those of dexamethasone (positive control).

[Diterpenoid constituents in Pseudolarix amabilis and their antitumor activities in vitro].

By various chromatographic techniques and extensive spectroscopic methods, 17 abietane diterpenoids were isolated from the dichloromethane fraction of the 95% ethanol cold-soak extracts of the seeds of Pseudolarix amabilis, namely pseudoamaol A(1), 12α-hydroxyabietic acid(2), 12-methoxy-7,13-abietadien-18-oic acid(3), 13-hydroxy-8,11,13-podocarpatrien-18-oic acid(4), 15-hydroxy-7,13-abietadien-12-on-18-oic acid(5), 8(14)-podocarpen-13-on-18-oic acid(6), holophyllin K(7), metaglyptin B(8), 7α-hydroxydehydroabietinsaure-methylester(9), 7-oxodehydroabietic acid(10), 15-hydroxy-7-oxodehydroabietinsaure-methy-lester(11), 15-methoxydidehydroabietic acid(12), 7-oxo-15-hydroxy-dehydroabietic acid(13), 15-hydroxydehydroabietic acid(14), 8,11,13-abietatriene-15,18-diol(15), 8,11,13-abietatriene-15-hydroxy-18-succinic acid(16), and 7ß-hydroxydehydroabie-tic acid(17). Compound 1 was a new compound. The isolated compounds were evaluated for their antitumor activities(HepG2, SH-SY5Y, K562), and compounds 8 and 17 showed potential cytotoxic activity against K562 cells, with IC_(50) values of 26.77 and 37.35 µmol·L~(-1), respectively.

seco-Sesquiterpenes and acorane-type sesquiterpenes with antiviral activity from the twigs and leaves of Illicium henryi Diels.

Chemical investigation of an alcohol extract from the twigs and leaves of Illicium henryi Diels resulted in the isolation of two new acorane-related seco-sesquiterpenes (1 and 3), two new acorane-related seco-norsesquiterpenes (2 and 4), one new 2-epi-cedrane sesquiterpene (5), eight new acorane-type sesquiterpenes (6-13), and a known major constituent of acorenone B (14). Their structures were established by interpreting extensive spectroscopic data, including HRESIMS, NMR (1H and 13C NMR, 1H-1H COSY, HSQC, and HMBC), and NOE difference spectra analysis. The absolute configurations of 1, 2, 4-7, 9, 10, and 14 were determined by X-ray crystallography, while chemical transformation methods were performed with compound 14 as the starting material to elegantly solve the absolute configuration issue of compounds 8 and 11-13. Notably, 1 and 2 are seco-sesquiterpenes that are related to acorane and possess an unusual ketal-linked hemiacetal in a 6,8-dioxabicyclo[3.2.1]octan-7-ol scaffold ring system. Plausible biosynthetic pathways for compounds 1-14, which were derived from the acorane skeleton, were proposed. All the isolated compounds (1-14) were evaluated for their antiviral and cytotoxic activities.

Dihydroflavonoid glycosides from Viscum album and their inhibitory effects on hepatic lipid accumulation and target identification.

Five undescribed dihydroflavonoid glycoside derivatives, namely albvisosides A‒E, together with two known compounds were isolated from the roots and stem leaves of Viscum album L. var. album. (European mistletoe). Their structures were determined by HRESIMS, 1D and 2D NMR, and ECD analysis. Albvisoside B exhibits significant inhibitory effect on hepatic lipid accumulation in HepG2 cells at very low concentrations (EC50: 0.7 nM). Using proteome integral solubility alteration assay, the direct targets or downstream effectors of albvisoside B were elucidated. As a result, 97 proteins were identified based on ligand-induced alterations in the protein thermal stability. Bioinformatics analysis indicated that albvisoside B primarily ameliorated oleic acid-induced lipid accumulation by regulating the selenoamino acids metabolism signaling pathway. RPL3, ADAM17, and RPL14 were likely to be involved in mediating the lipid-lowering effect of albvisoside B.

Chemical constituents from the fruits of Illicium simonsii and their antiviral activity and neuroprotective effect.

One undescribed diterpenoid illisimonone A, four undescribed sesquiterpenes named (±)-simonones A, simonterpenoids A and B, and two undescribed lignans, illisimonins A and B, along with five known compounds were isolated from the fruits of Illicium simonsii. Their structures were elucidated by extensive spectroscopic data. The absolute configuration of illisimonone A was determined by single-crystal X-ray diffraction analysis. Illisimonone A showed potential antiviral activity against the Coxsackie B3 virus, with an IC50 value of 3.70 µM. Illisimonin B and henrylactone A showed potential neuroprotective effects against oxygen-glucose deprivation induced cell injury in SK-N-SH cells, with survival rates of 57.6%, 58.0%, respectively.

Syringenes A-L: Bioactive dimeric eremophilane sesquiterpenoids from Syringa pinnatifolia.

A phytochemical investigation guided by 1H NMR and LC-MS data on the ethanol extract of Syringa pinnatifolia stems led to the isolation of 11 new dimeric eremophilane sesquiterpenoids, namely, syringenes A-K (1-11) and one known analog (12, syringene L). These structures were elucidated by extensive analysis of spectroscopic data, single-crystal X-ray diffraction, and computational methods. Biological assays revealed that 1-12 exhibited different degrees of anti-inflammatory effects, and 5 and 6 showed significant cytotoxicity against human hepatoma HepG2 cells with IC50 values of 12.3 and 12.9 µM, respectively. Furthermore, flow cytometry assays and western blot analysis revealed that 5 and 6 promoted the apoptosis of HepG2 cells by activating ERK. Finally, the molecular docking analysis implied that the carbonyl and hydroxy groups at the C-11/C-6' of 5 and 6 had a good binding affinity with ERK.

A pair of enantiomeric dimers with an unprecedented skeleton from stem barks of Syringa pinnatifolia.

A pair of enantiomers with a rearranged dimeric phenylethanol skeleton, namely (±)-disyringol A (1a and 1b), were isolated from the stem barks of Syringa pinnatifolia. The structures were established using IR, UV, MS, and NMR data, and their absolute configurations were resolved by experimental and calculated ECD data analysis. Their biosynthetic pathway was speculated on the basis of a phenylethanoid precursor and was proved by a total synthesis. Compounds 1a and 1b showed the inhibition against NO production in LPS-induced RAW264.7 cells with their IC50 values of 27.28 and 24.64 µM, respectively, however no protective effect was observed against the hypoxia-induced injuries to H9c2 cells.

Two new diterpenoids from the stems of Rhododendron dauricum as GABAA receptor agonists.

Two new diterpenoids, dauricumins A (1) and B (2), together with two known aromatic meroterpenoids (3 and 4), were isolated from the petroleum ether soluble fraction of the stems from Rhododendron dauricum through an HPLC-MS-SPE-NMR combination strategy. The absolute configurations of 1 and 2 were elucidated by ECD calculations and [Rh2 (OCOCF3)4]-induced CD spectrum analysis. In a membrane potential FLIPR assay, confluentin (4) showed an agonistic effect on GABAA receptor (EC50 = 20 µM).

Prenylated C6-C3 derivatives from the stems and branches of Illicium ternstroemioides A. C. Smith with antiviral activity.

Thirteen compounds were isolated from the lipid-soluble extracts of Illicium ternstroemioides A. C. Smith, including eleven previously undescribed prenylated C6-C3 compounds, a previously undescribed prenylated C6-C3 derivative-abscisic acid ester hybrid, and a known compound (4S)-illicinone I. Their structures and configurations were mainly elucidated by spectroscopic analyses, CD experiments and X-ray crystallography. (2S,4R,11S)-4-O-methyl-12-chloroillifunone C, (2S,4R,11R)-2,3-dihydro-4-O-methyl illioliganfunone D, and illiternfunol A were found to exhibit weak activity against Coxsackievirus B3, with IC50 values ranging from 27.8 to 33.3 µM. Illiternone B exhibited more potent activities against Coxsackievirus B3 and influenza virus A than did its geometric isomer illiternone A, with IC50 values of 7.7 µM and 2.5 µM, respectively. None of these compounds displayed cytotoxic activities.

Three Pairs of Enantiomeric Sesquiterpenoids from Syringa pinnatifolia.

Three pairs of enantiomeric sesquiterpenoids, (∓)-syringanoid A (1a and 1b) and (±)-pinnatanoids A (2a and 2b) and B (3a and 3b), that represent an unprecedented 5/4/6 tricyclic backbone and a rare 6/7 bicyclic backbone, respectively, were isolated from the peeled stems of Syringa pinnatifolia. The structures were elucidated by extensive spectroscopic analysis, single-crystal X-ray diffraction, a modified Mosher's method, and quantum chemical calculations. A plausible biotransformation pathway for 1-3 was proposed, and their cardiomyocyte-protective and anti-inflammatory activities were evaluated.

Bioactive prenylated C6-C3 derivatives from the stems and leaves of Illicium fargesii.

Seventeen new prenylated C6-C3 derivatives, namely, illifargeins A-M (1-13), including three pairs of enantiomers (1, 5, and 12) and one norillifargeal A (14), together with eight known analogues (15-22), were isolated from the stems and leaves of Illicium fargesii. The structures of the new compounds were elucidated using spectroscopic data (UV, IR, 1D and 2D NMR, and HRESIMS). Their absolute configurations were determined by using experimental and calculated ECD data analysis, as well as a modified Mosher's method. Compounds 1a, 1b, 2, 3, 5a, 7, 10, 11, 15, 16, 19, and 20 showed potential activity against Coxsackie virus B3, with IC50 values ranging from 6.23 to 33.33 µM. Compounds 9 and 15 exhibited potential activity against influenza virus A, with IC50 values of 11.11 and 19.24 µM, respectively. Compounds 2, 3, and 18 exhibited potential anti-oxidant activity, with IC50 values ranging from 1.43 to 6.71 µM.

Illihenin A: An Antiviral Sesquiterpenoid with a Cage-like Tricyclo[6.2.2.01,5]dodecane Skeleton from Illicium henryi.

Illihenin A (1), a novel sesquiterpenoid, was isolated from the roots of Illicium henryi. The structure was determined by spectroscopic analyses, ECD calculation, and single-crystal X-ray diffraction. Compound 1 represents a class of novel 5/7/6 tricyclic sesquiterpenoids featuring a rare cage-like tricyclo[6.2.2.01,5]dodecane core. A plausible biosynthetic pathway of 1 by rearrangement of allo-cedrane is proposed. Additionally, 1 showed potent antiviral activity against coxsackievirus B3 with an IC50 value of 2.87 µM.

Burchellin and its stereoisomers: total synthesis, structural elucidation and antiviral activity.

Burchellin and its analogues are a class of neolignan natural products containing a rare core with three contiguous stereogenic centers. In previous reports, racemic burchellin was synthesized without accessing each of the enantiomers. In this paper, a concise and efficient total synthetic route to divergently access the enantiomers of burchellin and those of its 1'-epi-diastereoisomer over six steps for each is disclosed, where each of the enantiomers was obtained by preparative chiral phase HPLC purification. The key steps include the construction of a 2,3-dihydrobenzofuran moiety by two Claisen rearrangements and a one-step rearrangement/cyclization and subsequent tandem ester hydrolysis/oxy-Cope rearrangement/methylation to furnish the basic skeleton of burchellin. The structures and absolute configurations of the four stereoisomers were determined using spectroscopic data analyses and comparison of experimental and calculated electronic circular dichroism data. These stereoisomers were found to have potent antiviral effects against coxsackie virus B3, and is the first time that bioactivity has been reported for these compounds.

Bioactive Sesquiterpenoids from the Peeled Stems of Syringa pinnatifolia.

Fourteen new sesquiterpenoids, alashanoids A-H (1, 2, and 4-9), (+)-2,9-humuladien-6-ol-8-one (3b), and five pairs of enantiomers (1 and 4-7), along with eight known analogues (3a and 10-16) were isolated from the stems of Syringa pinnatifolia. The structures were established using IR, UV, MS, and NMR data. The absolute configurations of the new compounds were resolved by X-ray diffraction, a modification of Mosher's method, and experimental and calculated ECD data analysis. The new sesquiterpenoids represent three skeletons: a rare 2,2,5,9-tetramethylbicyclo[6.3.0]-undecane (1), a humulane-type (2-8), and a caryophyllene-type (9) skeleton. Compounds 6a, 7, and 11 showed protective effects against hypoxia-induced injury to H9c2 cells at a concentration of 40 µM, and 5-7, 11, and 13 inhibited NO production in LPS-induced RAW264.7 macrophage cells with IC50 values ranging from 13.6 to 70.6 µM. These compounds decreased the TNF-α and IL-6 levels in RAW264.7 cells in a concentration-dependent manner at 20-80 µM.

Role of Gene Polymorphisms/Haplotypes and Plasma Level of TGF-ß1 in Susceptibility to In-Stent Restenosis Following Coronary Implantation of Bare Metal Stent in Chinese Han Patients.

Transforming growth factor (TGF)-ß1 has been implicated in the pathogenesis of restenosis. However, the role of TGF-ß1 polymorphisms in development of in-stent restenosis (ISR) after coronary bare metal stent (BMS) implantation in Chinese Han population has not been reported to date. The aim of this study was to explore the association between TGF-ß1 gene polymorphisms (-509C/T and 869T/C) and its plasma level in Chinese Han patients with BMS-ISR.We investigated 419 patients after successful coronary stent placement. All patients were reexamined by angiography. Genotyping for the two TGF-ß1 gene polymorphisms was performed using polymerase chain reaction-restriction fragment length polymorphism analysis. Plasma TGF-ß1 levels were measured by enzyme-linked immunosorbent assay.Ninety-two patients (21.96%) developed ISR during the follow-up period. The multivariable analysis adjusted for potential confounders and it revealed that the C allele of TGF-ß1 869T/C polymorphism was linked to an increased risk of ISR in both additive (Per each C allele) and dominant (TC+CC versus TT) models with odds ratios (ORs) of 1.88 (95% confidence interval [CI]: 1.21-2.84, P = 0.008) and 2.52 (95% CI: 1.40-4.80, P = 0.005), respectively. In accord with this, C-dominant CC/CT genotype was linked to higher plasma TGF-ß1 level compared to TT genotype. One haplotype (TC) (-509T, +869C) was associated with an increased risk for ISR (OR = 1.48, 95% CI: 1.06-2.06, P = 0.010).The C allele of TGF-ß1 869T/C polymorphism, correlated with high plasma TGF-ß1 level, represented an independent risk factor for BMS-ISR in Chinese Han patients with coronary artery disease.