New monoterpene phenol dimers from the fruits of Psoralea corylifolia.

Three new monoterpene phenol dimers, bisbakuchiols V-X (1-3), and two bakuchiol ethers (4 and 5), along with four known compounds (6-9) were isolated from the fruits of Psoralea corylifolia. Their structures were elucidated based on extensive spectral analysis. The absolute configurations of 1, 2, 4, and 5 were specified by quantum chemical calculations of ECD spectra.

Chiral separation and bioactivities of six pairs of enantiomeric dilignans from Magnolia officinalis var. biloba.

Six pairs of enantiomeric dilignans, (+)/(-)-magdiligols A-F, have been isolated from an ethanolic extract of the barks of Magnolia officinalis var. biloba. Their chemical structures were elucidated by extensive spectroscopic analyses, NMR calculation with DP4+ analysis, and the electronic circular dichroism spectra calculation. (+)/(-)-1-3 possessed a dihydrobenzopyran ring, while a propyl chain of 1 was linked via ether bond. (+)/(-)-Magdiligols D and E ((+)/(-)-4 and 5) were dilignans possessing a furan ring. (+)-Magdiligol B ((+)/(-)-2), (+)/(-)-magdiligol C ((+)/(-)-3), and racemes 2, 3, and 5 showed potential hepatoprotective effects against APAP-induced HepG2 cell damage, increased the cell viability from 65.4% to 72.7, 78.7.76.6, 73.9, 77.9 and 73.2%, via decreasing the level of the live enzymes ALH and LDH consistently. (+)/(-)-Magdiligols B-D ((+)/(-)-2-4) and (+)/(-)-magdiligol F ((+)/(-)-6) exhibited significant antioxidative activity. (+)/(-)-Magdiligols B-C ((+)/(-)-2 and 3), (-)-magdiligol D ((-)-4), and (+)-magdiligol E ((+)-5) displayed significant PTP1B inhibitory activity with IC50 values 1.41-3.42 µM. (+)/(-)-Magdiligol B ((+)/(-)-2), and its raceme (2) demonstrated α-glucosidase inhibitory activity with the IC50 values 1.47, 2.88 and 1.85 µM, respectively.

Hypoglycemic oligostilbenes from the stems of Caragana sinica.

Six new oligostilbenes, carastilphenols A-E (1-5) and (-)-hopeachinol B (6), with three reported oligostilbenes were obtained from the stems of Caragana sinica. The structures of compounds 1-6 were determined by comprehensive spectroscopy analysis, and their absolute configurations were determined by electronic circular dichroism calculations. Thus, natural tetrastilbenes were determined as absolute configuration for the first time. Also, we did several pharmacological essays. In the antiviral tests, compounds 2, 4 and 6 showed moderate anti-coxsackie virus B3 type (CVB3) effect on Vero cells activities in vitro with IC50 values of 19.2 âˆ¼ 69.3 µM; and compounds 3 and 4 showed different levels of anti-respiratory syncytial virus (RSV) effect on Hep2 cells activities in vitro with IC50 values of 23.1 and 33.3 µM, respectively. As for hypoglycemic activity, compounds 6-9 (10 µM) showed the inhibition of α-glucosidase in vitro with IC50 values of 0.1 âˆ¼ 0.4 µM; and compound 7 showed significant inhibition (88.8%, 10 µM) of protein tyrosine phosphatase 1B (PTP1B) with IC50 value of 1.1 µM in vitro.

Meroterpenoids with unknown skeletons from the leaves of Psidium guajava including one anti-inflammatory and anticoagulant compound: psidial F.

Four unknown meroterpenoids named as psidials D-G (1-4) together with 5 known compounds (5-9) had been obtained from the leaves of Psidium guajava. Their absolute structures were elucidated by spectral and calculated methods. Psidials DF (1-3) represented unknown carbon skeleton of the 3,5-diformylbenzyl phloroglucinol-coupled sesquiterpenoid. The possible biosynthetic pathway for 1-3 was postulated. In the bioactivity assay, psidial F (3) was found to possess anti-inflammatory and anticoagulant activities.

Bioactive monoterpene phenol dimers from the fruits of Psoralea corylifolia L.

Nine undescribed monoterpene phenol dimers, bisbakuchiols D-L (1-9), were isolated from the fruits of Psoralea corylifolia L. Their structures were elucidated based on extensive spectral analysis. The absolute configurations of 1-9 were specified by experimental and quantum chemical calculations of ECD spectra, and that of 1 was further established by X-ray diffraction analysis using Cu Kα radiation. Bisbakuchiols (1-4) were composed of two bakuchiols, one of which was cyclized via a C-7'/ C-12' single bond to form a six-member ring, and connect to each other by C-4-O-C-13' bonds. Bisbakuchiols (7-9) had a pyran ring by linkage of C-8-O-C-12. In the enzyme assay, compounds 5 and 9 exhibited significant PTP1B inhibitory activities with IC50 values of 0.69 and 0.73 µM, and compounds 1 and 3 showed moderate PTP1B inhibitory activities. Furthermore, a molecular docking simulation of PTP1B and active compounds 5 and 9 showed that these active compounds possess low binding affinities ranging from -6.9 to -7.1 kcal/mol.

Neuroprotective triterpene saponins from the leaves of Panax notoginseng.

Two new triterpene saponins, namely notoginsenoside Ng5 (1) and notoginsenoside Ng6 (2) were isolated from the leaves of Panax notoginseng, along with five known ones. Their structures were determined by chemical methods, NMR and X-ray experiments. The absolute configuration of compound 3 with four sugar units was confirmed by single crystal X-ray analysis. Compounds 2-4 and 6 inhibited PC12 cell damage induced by serum deprivation, and increased cell viability from 58.7 ± 6.7% to 66.7 ± 4.5%, 76.1 ± 6.1%, 64.7 ± 5.2% and 67.2 ± 5.0% at 10 µM, respectively.

Nine prenylated acylphloroglucinols with potential anti-depressive and hepatoprotective activities from Hypericum scabrum.

In our screening program for new biologically active secondary metabolites, nine new polycyclic polyprenyled acylphloroglucinols, hyperscabins D-L, together with three known compounds, were obtained from the aerial parts of Hypericum scabrum. The chemical structures of 1-9 were characterized by extensive spectroscopic analyses, nuclear magnetic resonance calculation with DP4+ probability analysis, and the electronic circular dichroism spectra were calculated. Compound 1 was an unusual prenylated acylphloroglucinol decorated with a 5-oxaspiro [4,5] deca-1,9-dione skeleton. Compound 2 was a newly identified spirocyclic polyprenylated acylphloroglucinol possessing a rare 5,5-spiroketal segment. Compounds 3, 8, and 10 (10 µM) exhibited pronounced hepatoprotective activity against d-galactosamine-induced WB-F344 cell damage in vitro assays. All test compounds (1, 3, and 7-12) demonstrated potential inhibitory effects at 10 µM against noradrenalinet ([3H]-NE) reuptake in rat brain synaptosome.

Novel oligomeric neolignans with PTP1B inhibitory activity from the bark of Magnolia officinalis var. biloba.

The barks of Magnolia officinalis var. biloba, Magnoliae cortex, have been used as traditional Chinese medicines for several centuries. In this study, phytochemical investigation of M. officinalis var. biloba bark extract afforded five pairs of novel enantiomeric oligomeric neolignans, (±)-mooligomers A-E (1-5). (±)-1 and (±)-2 were two diastereomeric pairs of enantiomers with six C6-C3 subunits, and (±)-4 was a pair of previously unreported tetrameric neolignans bearing eight C6-C3 subunits. (±)-5 is the first example of a naturally occurring trilignan featuring an eight-membered ring with a magnolol moiety. The absolute configurations of (±)-1-(±)-5 were elucidated on the basis of HRESIMS, 1D and 2D NMR spectroscopy and electronic circular dichroism (ECD) calculations. Among the compounds tested for their PTP1B inhibitory activities, (±)-2, (±)-4 and (±)-5 displayed significant PTP1B inhibitory activities with IC50 values of 0.14-2.10 µM. Furthermore, a Molecular docking simulation of PTP1B and active compounds [(±)-2, (±)-4 and (±)-5] exhibited that these active compounds possess low binding affinities ranging from - 5.9 to - 7.7 kcal/mol.

Bioactive flavonoid dimers from Chinese dragon's blood, the red resin of Dracaena cochinchinensis.

Seven flavonoid dimers, biflavocochins A-G, together with six known compounds were isolated from the red resins of Dracaena cochinchinensis (Chinese dragon's blood). Their structures were elucidated based on extensive spectroscopic analysis. The absolute configurations of 1-7 was assigned by experimental and quantum chemical calculated ECD spectra, and that of 4 was further established by X-ray diffraction analysis using Cu Kα radiation. Compounds 1-3 are novel dimers of homoisoflavonoid and dihydrochalcone with a unique dibenzopyran ring. Compounds 2, 6, 7 exhibited moderate PTP1B inhibitory activities in an enzyme assay. Compound 1 showed neuroprotective effect on serum deficiency-induced cellular damage in PC12 cells.

Neuroprotective racemic germacranolides from the roots of Chloranthus henryi.

Three pairs of new germacranolides, (+)/(-)-chlogermacrones A-C, along with two known analogues were obtained from the roots of Chloranthus henryi. Spectroscopic techniques and single-crystal X-ray crystallographic analyses were used for the structure elucidation of the compounds. All of the isolated compounds were tested for their neuroprotective effects on H2O2 damaged PC12 cells, compounds 3 and 5 increased cell viability from 43.4 ± 1.3% to 99.6 ± 8.7 and 68.1 ± 4.8% at 10 µM, respectively.

Cytotoxic 9,19-cycloartane Triterpenoids from the Roots of Actaea dahurica.

Eight undescribed 9,19-cycloartane type triterpenoid glycosides (cimdalglnoside A-H) and ten known analogues were obtained from the phytochemical research on the roots of Actaea dahurica (syn. Cimicifuga dahurica). All compounds were characterised by spectroscopic experiments, and chemical method. All the compounds isolated were assayed for cytotoxicity to five human cancer cell lines. Cimdalglnoside G showed promising cytotoxicities against Hela, and MCF-7 cell lines with IC50 values at 7.7 and 12.2 µM.

Dihydroagarofuran sesquiterpenoids esterified with organic acids from the leaves of Tripterygium wilfordii.

Six new and one known dihydroagarofuran sesquiterpenoids esterified with organic acids were obtained from the leaves of Tripterygium wilfordii. Spectroscopic techniques (UV, IR, MS, NMR, ORD and CD) were used for the structure elucidation of the compounds. The structures of compounds 1 and 2 were confirmed by X-ray single crystallographic analyses. The inhibitory effects on NO production in LPS-induced macrophages of 1-7 were conducted. At 10 µmol/L, compounds 1, 2 and 7 showed moderate inhibitory effects on NO production in LPS-induced macrophages with inhibitory rate at 31.2 ±â€¯3.6, 40.9 ±â€¯4.3, and 66.79 ±â€¯3.1%, respectively.

Magmenthanes A-H: Eight new meroterpenoids from the bark of Magnolia officinalis var. Biloba.

Eight new meroterpenoids with different types of monoterpene units, namely, magmenthanes A-H (1-8), were identified from the bark of Magnolia officinalis var. biloba. Magmenthane A (1) possesses a 1,3-dioxabicyclo [4.3.01,5] nonane skeleton, 1-5 possess five pairs of enantiomers and 6 possesses a 1,1'-diallyl-biphenyl fragment. The structures of 1-8 were elucidated on the basis of 1D and 2D NMR, HRESIMS and electronic circular dichroism (ECD) calculations. Compounds 5 and 8 displayed significant PTP1B inhibitory activities with IC50 values of 4.38 and 3.88 µM, respectively.

Cytotoxic 9,19-cycloartane type triterpenoid glycosides from the roots of Actaea dahurica.

Ten undescribed 9,19-cycloartane type triterpenoid glycosides (cimdahxynoside A-J) and five known analogues were obtained from the phytochemical research on the roots of Actaea dahurica (syn. Cimicifuga dahurica). All compounds were characterised by spectroscopic experiments, chemical method and X-ray Single-crystal diffraction analysis. Cimdahxynoside A represented the first X-ray crystallography of 9,19-cycloartane type triterpenoid diglycoside. The cytotoxicity of all compounds were tested against five human cancer cell lines. Cimdahxynoside F showed significant cytotoxicity, with IC50 values between 6.6 and 9.9 µM.

The isolation, absolute configuration and activities of 18(4 → 3)-abeo-abietane lactones from Tripterygium wilfordii.

Phytochemical studies on the leaves of Tripterygium wilfordii led to the isolation of seven new 18(4 → 3)-abeo-abietane lactones, triptergulides E - K (1 - 7). The structure of the new compounds was elucidated on the basis of their spectroscopic analysis, and the absolute configurations of compounds were confirmed by ECD, calculated ECD, and X-ray crystallographic analysis using anomalous scattering of Cu Kα radiation. Some compounds showed moderate inhibitory activities against NO, IL-6, and TNF-α production in LPS RAW 264.7 macrophage in vitro.

New 18(4→3)-Abeo-Abietanoids from Tripterygium wilfordii.

Three 18(4→3)-abeo-abietanoids, a new natural product and two new compounds, named tripordolides A⁻C (1⁻3), were isolated from the leaves of Tripterygium wilfordii. Their structures were elucidated on the basis of their spectroscopic analysis, and the absolute configuration of compounds was confirmed by CD and X-ray crystallographic analysis using anomalous scattering of Cu Kα radiation. Compounds 1 and 3 showed moderate inhibitory activities against NO production in lipopolysaccharide-induced (LPS) RAW 264.7 macrophages in vitro.

Nototronesides A-C, Three Triterpene Saponins with a 6/6/9 Fused Tricyclic Tetranordammarane Carbon Skeleton from the Leaves of Panax notoginseng.

Three triterpene saponins, nototronesides A-C (1-3), possessing an unprecedented 6/6/9 fused tricyclic tetranordammarane core, were isolated from the leaves of Panax notoginseng. Their structures were elucidated on the basis of spectroscopic data, and the structure of sapogenin (1a) was further confirmed by X-ray crystallography. The existence of 1-3 adds a new dimension to the diversity of the triterpene family. Moreover, compound 2 showed a moderate neuroprotective effect on serum deficiency-induced cellular damage in PC12 cells.

Magterpenoids A-C, Three Polycyclic Meroterpenoids with PTP1B Inhibitory Activity from the Bark of Magnolia officinalis var. biloba.

Magterpenoid A (1), possessing a rare 4,6,11-trioxatricyclo[5.3.1.01,5]undecane framework with an irregular monoterpenoid moiety, magterpenoid B (2), with an unprecedented 6/6/6/6 polycyclic skeleton, and magterpenoid C (3), a novel terpenoid quinone with a C6-C3 unit, were isolated from the bark of Magnolia officinalis var. biloba. Plausible biogenetic pathways of 1-3 are presented. Compounds 1 and 3 exhibited significant PTP1B inhibitory activities with IC50 values of 1.44 and 0.81 µM, respectively.

Hepatoprotective glycosides from the rhizomes of Imperata cylindrical.

Three new C-methylated phenylpropanoid glycosides (1, 2), a new 8-4'-oxyneolignan (3), together with two known analogs (4, 5), were isolated from the rhizomes of Imperata cylindrical Beauv. var. major (Nees) C. E. Hubb. Their structures were determined by spectroscopic and chemical methods. Compounds 1, 2, and 5 (10 µM) exhibited pronounced hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced HepG2 cell damage in vitro assays. Furthermore, their antioxidant activities against Fe2+-cysteine-induced rat liver microsomal lipid peroxidation and the effects on the secretion of TNF-α in murine peritoneal macrophages (RAW264.7) induced by lipopolysaccharides were evaluated.

Triptergosidols A-D, nerolidol-type sesquiterpene glucosides from the leaves of Tripterygium wilfordii.

Four new nerolidol-type sesquiterpene glucosides, triptergosidols A-D (1-4) were isolated from the leaves of Tripterygium wilfordii. Three aglycones, named triptergerols A (1a), B (2a), and C (3a), were acquired by enzymatic hydrolysis of 1-3. The structures of nerolidol-type sesquiterpenes were elucidated on base of kinds of spectroscopic analysis, and their absolute configurations were determined by CD method. In addition, compounds 1-4 were tested for cytotoxicity against two cell lines and inhibitory effects against NO production in RAW264.7 macrophage.