Anti-inflammatory constituents from the stems and leaves of Glycosmis ovoidea Pierre

NO inhibitory constituents from Glycosmis craibii var. glabra

Six novel compounds, comprising three quinolones (1a, 1b, and 2) and three flavanones (3-5), along with seven known analogs (6-13), were isolated from the 95% EtOH extract of the stems and leaves of Glycosmis craibii var. glabra. The structures of the new compounds were elucidated using HR-ESI-MS, UV, and 1D and 2D nuclear magnetic resonance (NMR) data analysis. The absolute configurations were determined through Mosher ester and electronic circular dichroism (ECD) spectral analysis. Compounds 2, 6, 9, and 10 demonstrated inhibition of nitric oxide (NO) production stimulated by lipopolysaccharide in BV-2 microglial cells, with IC50 values ranging from 13.5 to 20.1 μmol·L-1, comparable to the positive control, dexamethasone.

Structurally diverse sulphur-containing amides from Glycosmis craibii with their potential antiproliferative activities

Fourteen new sulphur-containing amides, glycocramides A-N (1-14), as well as nine known analogues (15-23) were isolated and characterized from Glycosmis craibii Tanaka. The chemical structures of new sulphur-containing amides 1-14 were ambiguously elucidated by extensive spectroscopic methods, while the known compounds 15-23 were identified by the comparison of their experimental spectral data with those described data in the literatures. The antiproliferative effects of all isolated sulphur-containing amides were evaluated in vitro. As a result, part of sulphur-containing amides showed remarkable inhibitory effects against MGC-803 cell line with IC₅₀ values ranging from 13.12 ± 0.10 to 20.03 ± 0.13 μM. These research results suggest that the sulphur-containing amides are potentially to be developed as a new natural anti-tumor drugs.

Triterpenoids from Uncaria macrophylla as ferroptosis inhibitors

Seven undescribed triterpenoids were obtained from the ethanol extract of the dried stems of Uncaria macrophylla Wall. (Rubiaceae).All of the isolates were urs-28-oic acid or olean-28-oic acid skeletons, including three triterpenoids with rare 3β,23-(1R-4-hydroxy-butyl-1,1-dioxy) or 23-(2R-tetrahydrofuran-2-oxy) substituents. Five triterpenoids showed promising inhibitory activity against erastin-induced ferroptosis in PC12 cells, while 3β,6α,23-trihydroxy-olean-12-en-28-oic acid was the most significant inhibitor to resist ferroptosis by activating the Nrf2/SLC7A11/GPx4 axis with an EC₅₀ value of 4.2 ± 0.7 μM.