New lignans from Phyllanthodendron dunnianum.

A new lignan phyllanins A (1) and a lignan phyllanins B (2) for which the absolute configuration was determined for the first time, along with four known lignans (3-6) were isolated from the branch and leaf extracts of Phyllanthodendron dunnianum. Their planar structures were mainly determined by a combination of 1D and 2D NMR, HRESIMS spectral analyses, and the absolute configurations of the compounds 1 and 2 were established by DFT GIAO 13C NMR and electronic circular dichroism (ECD) calculations. In addition, all these six lignans were firstly tested for the antibacterial activities against MRSA, Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and Escherichia coli. Among these compounds, 2 and 5 showed potential antibacterial activities against MRSA and S. aureus with MIC values of 4 and 8 µg/mL, respectively.

Three new metabolites from the endophyte Fusarium proliferatum T2-10.

One new cyclopeptide, cyclo-(L-Trp-L-Phe-L-Phe) (1), one new 2-pyridone derivative, fusarone A (3), and one new natural indole derivative, ethyl 3-indoleacetate (4), along with six known compounds were isolated from the endophytic fungus Fusarium proliferatum T2-10. The planar structures of three new compounds were identified by spectral methods including 1D and 2D NMR techniques, and the absolute configuration of compound 1 was elucidated by Marfey-MS method. In addition, all compounds were evaluated for their cytotoxic and antibacterial activities in vitro. Compound 2 showed remarkable cytotoxic activities against two human hepatoma cell lines SMMC7721 and HepG2 with IC50 values of 5.89 ± 0.74 and 6.16 ± 0.52 µM, and showed moderate antibacterial activities against Staphylococcus aureus and Enterococcus faecalis with MIC values of 7.81 and 15.62 µg/mL, respectively.

A new abietane diterpenoid from Lycopodium complanatum.

A new abietane diterpenoid, 1ß, 11-epoxyabieta-12-hydroxy-8, 11, 13-triene-7-one (1), along with three known compounds (2-4), was isolated from Lycopodium complanatum. Their structures were confirmed by the analysis of 1D, 2D NMR and HRESIMS data, and comparison with previous spectral data. All compounds were tested for inhibitory activities against A549, HepG2 and MCF-7 tumor cell lines. [Figure: see text].

Pseudocercones A-C, three new polyketide derivatives from the endophytic fungus Pseudocercospora sp. TSS-1.

Chemical investigation of an EtOAc extract of the endophytic fungus Pseudocercospora sp. TSS-1 led to the isolation of three new polyketide derivatives, including one benzophenon derivative (1), two spirocyclic polyketides (4 and 5), along with four known compounds (2, 3, 6 and 7). Their structures and the absolute configurations were characterized by means of NMR, HRESIMS, 13C NMR and theoretical electronic circular dichroism calculations. Furthermore, all compounds were evaluated for their antibacterial activity against four microbial pathogens (Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and Escherichia coli), and compounds 1, 2, 3 and 5 displayed significant selective antibacterial activity against S. aureus with MIC values ranging from 3.9 to 7.8 µg/mL.

Lignans and phenolic constituents from Eucommia ulmoides Oliver.

Two new lignans, noreucol A (1) and (+)-epicycloolivil (2), along with seven known compounds (3-9) were isolated from the aqueous extract of Eucommia ulmoides Oliver. Compound 1 was a new norlignan and 2 was an epimer at C-7 of (+)-cycloolivil (3). Their structures were elucidated by spectroscopic methods, and the absolute configurations of new compounds were determined by conformational analysis and DFT theoretic electronic circular dichroism spectra calculations. In addition, the neuroprotective activity of compounds 1-3 against glutamate-induced HT-22 cells injury were evaluated, and only compound 1 exhibited moderate effect at the concentrations ranging from 10 ∼ 50 µM.

New cytotoxic biflavones from Selaginella doederleinii.

Three new biflavones, apigenin-(3',8″)-chrysin (1), (2S)-2,3-Dihydroametoflavone 5,4'-dimethyl ether (2), and (2S)-5″,7″-Dihydroxy-2″-phenoxychromonyl-(4'″,3')-naringenin (3), together with seven known biflavones (4-10) were isolated from the 75% EtOH extract of Selaginella doederleinii. The structures of new compounds were established by application of spectroscopic methods, including 1D and 2D NMR, HRMS, and CD measurements. In addition, all new compounds were evaluated for their cytotoxic potential against three human cancer cell lines A549, MCF-7, and SMMC-7721 in vitro. Compound 2 exhibited potent cytotoxic activity with IC50 values ranging from 6.35 to 10.18 µM.

[Studies on flavonoid glycosides of Sarcandra glabra].

OBJECTIVE: To in vestigate the chemical constituents of Sarcandra glabra and obtain a more comprehensive understanding on its effective components. METHOD: The constituents were isolated by various column chromatographic method and their structures were elucidated by physico-chemical properties and spectroscopic analysis. RESULT: Five flavonoid glycosides were isolated and identified as kaempferol-3-O-beta-D-glucuronide (1), quercetin-3-O-alpha-D-glucuronide (2), quercetin-3-O-beta-D-glucuronopyranoside methyl ester (3), 5, 7, 4'-trihydroxy-8-C-beta-D-glucopyranosyl flavanone (4), neoastilbin (5), 5-O-caffeoylquinic acid methyl ester (6), 3, 4-dihydroxybenzoic acid (7), isofraxidin (8). CONCLUSION: Compounds 1-6 were isolated from the genus Sarcandra for the first time. The glucuroide compounds compounds 1-3, were first isolated from the genus Sarcandra.

[Studies on constituents of Oldenlandia diffusa].

OBJECTIVE: To investigate the chemical constituents of Oldenlandia diffusa. METHOD: The column chromatography with polyamide Sephadex LH -20, silica gel as packing materials and HPLC, were used to separate and purify the chemical components. The structures were elucidated on the basis of physicochemical properties and spectral data. RESULT: Nine compounds were isolated and identified as 2, 6-dihydroxy-1-methoxy-3-methylanthraquinone (1), 2-hydroxy-1-methoxy-3-methylanthraquinone (2), 2-hydroxy-3-methylanthraquinone (3), quercetin-3-O-[2-O-(6-O-E-sinapoyl)-beta-D-glucopyranosyl]-beta-glucopyranoside (4), quercetin-3-O-[2-O-(6-O-E-feruloyl)-beta-D-glucopyranosyl]-beta-glucopyranoside (5), kaempferol-3-O-[2-O-(6-O-E-feruloyl)-beta-D-glucopyranosyl]-beta-galactopyranoside (6), quercetin-3-O-(2-O-beta-D-glucop-yranosyl)-beta-D-glucopyranoside (7), rutin (8) and quercertin (9). CONCLUSION: Compounds 1 and 8 were obtained from this plant for the first time, and compound 1 was a new compound.

[Water-soluble chemical constituents of Swertia davidi Franch].

AIM: To study the active constituents of Swertia davidi Franch. METHODS: Column chromatographies on silica gel, Sephadex LH-20 and Diaion-201 et al. were used to isolate and purify the chemical components. Their structures were identified by UV, IR, MS, NMR and 2D-NMR. RESULTS: These compounds were elucidated as 8-O-beta-D-glucopyranosyl-1, 3, 5-trihydroxyxanthone (I), 5-O-beta-D-glucopyranosyl-1, 8-dihydroxy-3-methoxyxanthone (II), 5-O-beta-D-glucopyranosyl-1, 3, 8-trihydroxyxanthone (III) and swertamarin (IV). CONCLUSION: Compound III is a new xanthone glucoside. The other compounds were isolated from this plant for the first time.