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.

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.

[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.

Pseudoamaolides A-O, anti-inflammatory triterpene spiroketal lactones from seeds of Pseudolarix amabilis.

Fifteen new triterpenoids (1-15), along with twenty known ones (16-35), were isolated from Pseudolarix amabilis. The triterpenoid structures include multiple skeleton types, such as 2,3-seco-cycloartane, 3,4-seco-cycloartane, 3,4:9,10-diseco-cycloartane, and 3,4:8,9:9,10-triseco-cycloartane, as elucidated by extensive spectroscopy (1D NMR, 2D NMR, HRESIMS, and IR) and single-crystal X-ray diffraction. The anti-inflammatory activities of compounds 1-35 were evaluated. Compounds 3, 11, 16, 24, 25, and 26 suppressed the transcription of the NF-κB-dependent reporter gene in LPS-induced 293T/NF-κB-Luc cells with IC50 values of 0.12, 0.10, 0.30, 0.09, 0.49, and 0.35 µM, respectively. In addition, compound 16 showed anti-inflammatory activity against xylene-induced ear swelling in vivo with an inhibition rate of 44.7 % (30 mg/kg). Compound 16 significantly improved the disease activity index (DAI) of ulcerative colitis at a dose of 400 mg/kg in a dextran sodium sulfate (DSS)-induced mouse model of experimental ulcerative colitis (P < 0.01).

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).

[Chemical constituents of Physalis minima].

Fifteen compounds(1-15) were isolated from the 95% EtOH extract of the whole herb of Physalis minima by various chromatography techniques including silica gel, Sephadex LH-20, middle chromatogram isolated gel(MCI), octadecyl silica(ODS), and semi-preparative high performance liquid chromatography(HPLC). Their structures were elucidated by infrared spectroscopy(IR), ultraviolet spectroscopy(UV), high-resolution electrospray ionization mass spectrometry(HR-ESI-MS), nuclear magnetic re-sonance(NMR), and circular dichroism(CD) as(5S)-5,11-dihydroxy-3-methyl-5-pentylfuran-2(5H)-one(1), withaphysalin R(2), withaphysalin Q(3), withaphysanolide A(4), phaseic acid(5), grasshopper ketone(6), 3S,5R-dihydroxy-6S,7-megastigmadien-9-one(7), vanillic acid(8), 2-trans,4-trans-abscisic acid(9), capillasterolide(10), 5,3'-dihydroxy-3,7,4'-trimethoxyflavone(11),(-)-loliolide(12), 4-hydroxyacetophenone(13), acetosyringone(14), and aurantiamide acetate(15). Compound 1 was a new butenolide, and compounds 5-7 and 10-12 were isolated from the Physalis for the first time. Compounds 4, 13, and 15 were isolated for the first time from P. minima. Moreover, their anti-inflammatory activity was evaluated in vitro. Compound 12 was found to possess an inhibitory effect on the transcription of an NF-κB-dependent reporter gene in LPS-induced 293 T/NF-κB-luc cells at 10 µmol·L~(-1), showing an inhibitory rate of 62.31%±4.8%.