Ent-labdane-type diterpene glycosides obtained from Rubus chingii Hu and their inhibitory effects on PDE5A activity.

In this study, 16 new ent-labdane-type diterpene glycosides, designated as goshonosides J1-J16 (1-16), along with nine previously known diterpene glycosides (17-25) were extracted from the fruits of Rubus chingii Hu. The structures of goshonosides J1-J16 were elucidated using various analytical techniques, such as nuclear magnetic resonance, electron capture detector ECD, high-resolution electrospray ionization mass spectrometry HREIMS, single-crystal X-ray diffraction, and hydrolysis. Furthermore, the isolates' efficacy in inhibiting the activity of phosphodiesterase type 5 A was evaluated. Goshonosides J1, J2, and G effectively inhibited the activity of the aforementioned enzyme (IC50 values: 6.15 ± 1.76, 3.27 ± 0.65, and 9.61 ± 2.36 µM, respectively). Our findings highlight the remarkable structural diversity of bioactive compounds in R. chingii Hu and offer insights into the use of this shrub.

Two new 19-norbufadienolides with cardiotonic activity isolated from the venom of Bufo bufo gargarizans.

Two new 19-norbufadienolides (1 and 2) and one new 14,15-epoxy bufadienolide (3) alongside 16 known bufadienolides (4-19) were isolated from Bufonis Venenum that originated from the skin and parotid venom glands of an Asiatic toad (Bufo bufo gargarizans Cantor). The structures of these bufadienolides were elucidated based on the interpretation of their HRESIMS and NMR data. Compound 1, which had a unique peroxide, was established through extensive single-crystal X-ray diffraction. The two 19-norbufadienolides exhibited more potent cardiotonic activity in the isolated toad heart model and lower cytotoxicity against U87, U251, and LN-18 cell lines than other bufadienolides, such as bufalin and bufotalin. The results suggested that 19-norbufadienolides might be more suitable for developing cardiotonic agents with low cytotoxicity.

Four new bis-iridoids isolated from the traditional Tibetan herb Pterocephalus hookeri.

Pterocenoids A-E (1-4), which Pterocenoids A(1) is one novel dimer containing a pyridine monoterpene alkaloid; and Pterocenoids B-E (2-4) are rare arranged non-glycosidic bis-iridoids were isolated from Pterocephlus hookeri. The structures of the compounds were established by 1D and 2D NMR spectroscopy and mass spectrometry. All bis-iridoids isolated from P. hookeri were found to possess secoiridoid/iridoid subtype skeletons. Hence, bis-iridoids can be regarded as the chemotaxonomic markers of P. hookeri. The origins of the new bis-iridoids (1-4) were postulated and their activities of inhibition of the NF-κB pathway were assayed and compounds 1-3 showed moderate activity in inhibiting NF-κB.

[Study on quality standard for Humulus scandens].

To control the quality of Humulus scandens, the quality standard was established in this study. According to the method recorded in the Appendix of Chinese Pharmacopoeia (2010 Edition) , the water and ash inspections were carried out. The component luteoloside and cosmosiin in Humulus scandens were identified and assayed by TLC and HPLC. The results showed a strong characteristics microscopic of Humulus scandens, and trichoromethane-methanol-formic acid (10: 3: 0. 3) as the mobile phase of TLC, the spots at 365 nm with a UV lamp was clear. The 16 batches of samples were analyzed by HPLC with a gradient elution of acetonitrile and phosphate solution (0.2%) at a flow rate of 1.0 mL · min(-1) and detected at 350 nm. The content of luteoloside was 0.015%- 0.651% (average 0.148%); the content of cosmosiin was 0.003%-0.118% (average 0.036%). The linear calibration curve of luteoloside and cosmosiin was acquired in the ranges of 0.011-0.364 g · L(-1) (r = 1.000 0) and 0.003-0.096 g · L(-1) (r = 1.000 0), respectively. The average recovery was 100.5% and 98.5%, respectively. The methods are convenient and reliable, which can be ap- plied for quality assessment of Humulus scandens.

Novel flavonoids from the leaves of Actinidia valvata Dunn: structural elucidation and antioxidant activity.

Two novel flavonoids, kaempferol 3- O- α-L-rhamnopyranosyl (1-3) (2,4-di- O-acetyl-α-L-rhamnopyranosyl) (1-6) ß-D-galactopyranoside (1) and kaempferol 3- O-α-L-rhamnopyranosyl (1-3) (4-O-acetyl-α-L-rhamnopyranosyl) (1-6) ß-D-galactopyranoside (2), along with three known ones, kaempferol-3- O-ß-D-galactopyranoside (3), kaempferol (4), and 7-hydroxychromone (5), have been isolated from the leaves of Actinidia valvata Dunn, and their structures were elucidated based on spectroscopic methods. Compounds 1-3 exhibited dose-dependent activity in scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals, superoxide anion radicals, and hydroxyl radicals, and inhibited lipid peroxidation of mouse liver homogenate IN VITRO.