Isoprenoid flavonoids isolated from Sophora davidii and their activities induces apoptosis and autophagy in HT29 cells.

Four previously undescribed isoprenoid flavonoids (2-5) were isolated from Sophora davidii, along with five known analogues. The structures of the compounds were established through comprehensive analysis of spectroscopic data, including HRESIMS, 1D and 2D NMR, and absolute configurations determined by theoretical calculations, including ECD and NMR calculation. The cytotoxic effects of the isolated compounds on human HT29 colon cancer cells were evaluated using the MTT assay, compound 1 exhibited cytotoxicity against human HT29 colon cancer cells with an IC50 value of 8.39 ± 0.09 µM. Studies conducted with compound 1 in HT29 cells demonstrated that it may induce apoptosis and autophagy in HT29 by promoting the phosphorylation of P38 MAPK and inhibiting the phosphorylation of Erk MAPK.

Structural elucidation of lactone derivatives from Dendrobium pendulum.

Six lactone derivatives, including four α-pyrones derivatives (1-4), two α-furanone derivatives (5 and 6), were isolated from the Dendrobium pendulum. Structural elucidation of these undescribed lactone derivatives were accomplished on the basis of detailed nuclear magnetic resonance analysis, and the absolute configurations of compounds 1-4 were confirmed by electronic circular dichroism (ECD) techniques. The cytotoxic effects of isolated compounds on human breast cancer cell MDA-MB-231 were evaluated by the MTT assay.

Complete 1 H and 13 C assignments of two new sesquiterpenoids from Dendrobium aduncum.

Two new sesquiterpenoids, dendroaduoid A (1) and dendroaduol (2), together with four known sesquiterpenoids were isolated from the stems of Dendrobium aduncum. Their structures were identified by HR-ESI-MS and NMR experiments, and the complete assignments of 1 H and 13 C NMR data for two new sesquiterpenoids were obtained by the aid of HSQC, HMBC, 1 H-1 H COSY, NOESY, and ECD techniques. The cytotoxic effects of the isolated compounds on four tumor cell lines (HCT-116, HepG2, A549, and SW1990) were evaluated using MTT assay. Otherwise, the inhibitory activity of these six sesquiterpenoids on glycosidase was also evaluated.

Two new alkaloids from Dendrobium nobile Lindl. exhibited neuroprotective activity, and dendrobine alleviated Aß1-42 -induced apoptosis by inhibiting CDK5 activation in PC12 cells.

Dendrobium nobile Lindl. is registered in the Chinese Pharmacopoeia as a traditional medicine. Phytochemical investigation of the ethanol extract of D. nobile Lindl. stems yielded three alkaloid compounds, including two new compounds dendroxine B (2) and denrine B (3) as well as one known compound dendrobine (1). Here, we identified the structure of these compounds using spectroscopic analyses and compared them with those described in previous studies. Compounds 1-3 were found to show protective effect against amyloid-ß 1-42 (Aß1-42 )-induced neurotoxicity in rat pheochromocytoma (PC12) cells, among which dendrobine exhibited the most significant neuroprotective effect. Hoechst 33342/propidium iodide staining indicated that dendrobine ameliorated Aß1-42 -induced apoptosis. Moreover, quantitative real-time polymerase chain reaction and western blot analysis analysis demonstrated that dendrobine suppressed the activation of cyclin-dependent kinase 5 (CDK5), upregulated Bcl-2 expression, and downregulated Bax, cyto-c, and caspase-3 expression. Molecular docking analysis and surface plasmon resonance assay suggested that dendrobine directly bound to CDK5 protein with a KD value of 2.05 × 10-4 M. In summary, alkaloids are the neuroprotective constituents of D. nobile Lindl., and dendrobine protected PC12 cells against Aß1-42 -induced apoptosis by inhibiting CDK5 activation.

Dihydrophenanthrenes and phenanthrenes from Dendrobium terminale.

Two previously undescribed dihydrophenanthrene derivatives (1 and 2) were isolated along with twelve known analogues from the whole plant of Dendrobium terminale. The structures of the new compounds were elucidated on the basis of detailed spectroscopic analysis. The NMR data of known phenanthrene derivatives (7 and 9) were revised by 2D NMR. The isolated compounds were evaluated for cytotoxicity against three kinds of tumor cell lines (sw1990, HCT-116, and HepG2). Especially compounds 11 and 14 showed stronger antitumor effects, and the structure-activity relationship of these compounds was discussed.

Dendrobine-type alkaloids from Dendrobium nobile.

Six dendrobine-type alkaloids were isolated from the tubes of Dendrobium nobile by silica gel, Sephadex LH-20 gel column chromatography, and preparative HPLC. Compound 1 is a new alkaloid containing a pair of amide tautomers, whereas compound 2 is a new dendrobine-type alkaloid. By using spectroscopic techniques including 1 D and 2 D NMR, the structures of compounds 1‒6 were identified as N-methoxylcarbonyldendrobine (1), dendronboic acid (2), dendrobine (3), 6-hydroxyldendrobine (4), dendrobine N-oxide (5), and denrine (6). The cytotoxic effects of the isolated compounds on two human tumour cell lines (HCT-116 and SW1990) were evaluated using MTT assay.

Dihydrophenanthrofurans and bisbibenzyl derivatives from the stems of Dendrobium nobile.

Two new dihydrophenanthrofurans (1 and 2) and two new bisbibenzyl derivatives (3 and 4) were isolated from the traditional Chinese medicinal plant Dendrobium nobile, along with four known compounds (5-8). The absolute configurations of compounds 1 and 4 were elucidated through extensive NMR and ECD spectroscopic analyses. New compounds showed no antimicrobial activity against four gram-positive bacterial strains and four gram-negative bacteria at the concentration of 1 mg/mL, but displayed significant cytotoxic activity against HepG2 human hepatic cell line with the IC50 values ranging from 1.25 µM to 19.47 µM.

[Design, synthesis and antitumor activities of novel E-substituted 2,3-diaryl propenoic acyloxy phosphonate derivatives].

According to the super-position principle of the reinforcement of biological activities, a series of novel E-substituted 2, 3-diaryl propenoic acyloxy phosphonate derivatives were designed and synthesized. And the structures of the target compounds were confirmed by IR, 1H NMR, 13C NMR and elemental analysis. Furthermore, the cytotoxicities of all compounds on A-549, SGC-7901 and EC-109 in vitro were evaluated by MTT assay, and some of them showed good antitumor activity. Among the active compounds, especially, the IC50 value of compound 3e was (12.7 ± 1.9) µmol x L(-1) against A-549 cells, similar to cisplatin [IC50 = (8.0 ± 1.5) µmol x L(-1)], compounds 3g and 3k had better inhibition effect on EC-109 cells growth, with the IC50 values of (9.5 ± 1.8) µmol x L(-1) and (11.5 ± 0.9) µmol x L(-1) respectively, and compounds 3i and 3k exhibited good cytotoxic property on A-549, SGC-7901 and EC-109, which were worth further investigation.

[Study on the chemical constitutes of submerged cultivation mycelium of Cordyceps jiangxiensis].

OBJECTIVE: In an effort to investigate the chemical constitutes of submerged cultivation mycelium of Cordyceps jiangxiensis anamorph. METHODS: The mycelia of C. jiangxiensis anamorph produced by submerged cultivation technique were separated and purified using various chromatographic techniques such as repeated liquid column chromatography, preparative thin layer chromatography etc. , and then the chemical structures of compounds obtained were elucidated on the basis of physicochemical analysis and spectroscopic techniques such as 1H-NMR, 13C-NMR and MS. RESULTS: Nine compounds were obtained from the petroleum ether and ethyl acetate extractive fractions of mycelial methanol extract, and were identified as follows: uracil (I), adenine (II), adenosine (III), uridine (IV), 3'-methoxyuridine (V), succinic acid (VI), nicotinic acid (VII), 1-monostearin (VIII), tetracosanoic acid (IX). CONCLUSION: Chemical constitutes of C. jiangxiensis anamorph are systematically separated for the first time, and compounds V, VII, VIII, and IX obtained are separated from Cordyceps species firstly.