Alkaloids and Terpenoids from Trigonostemon lutescens and their Potential Antiproliferative Activity

Major specialized natural products from the endangered plant Heptacodium miconioides, potential medicinal uses and insights into its longstanding unresolved systematic classification

A comprehensive phytochemical investigation of the flower buds and leaves/twigs of Heptacodium miconioides, a cultivated ornamental plant native to China and categorized as 'vulnerable', has led to the isolation of 45 structurally diverse compounds, which comprise 18 phenylpropanoids (1-4, 7-20), 11 pentacyclic triterpenoids (5, 6, 21-29), eight secoiridoid glycosides (30-37), three quinic acid derivatives (38-40), and a few miscellaneous components (41-45). Among them, (+)-α-intermedianol (1), (+)-holophyllol A (2), and (-)-pseudolarkaemin A (3) represent previously unreported enantiomeric lignans, while (+)-7'(R)-hydroxymatairesinol (4) is an undescribed naturally occurring lignan. Heptacoacids A (5) and B (6) are undescribed 24-nor-urs-28-oic acid derivatives. Their chemical structures were determined by 2D-NMR, supplemented by evidence from specific rotations and circular dichroism spectra. Given the uncertainty surrounding the systematic position of Heptacodium, integrative taxonomy (ITA), a method utilized to define contentious species, is applied. Chemotaxonomy, a vital aspect of ITA, becomes significant. By employing hierarchical clustering analysis (HCA) and syntenic pattern analysis methods, a taxonomic examination based on the major specialized natural products from the flower buds of H. miconioides and two other Caprifoliaceae plants (i.e., Lonicera japonica and Abelia × grandiflora) could offer enhanced understanding of the systematic placement of Heptacodium. Additionally, compounds 39 and 40 displayed remarkable inhibitory activities against ATP-citrate lyase (ACL), with IC50 values of 0.11 and 1.10 μM, respectively. In summary, the discovery of medical properties and refining systematic classification can establish a sturdy groundwork for conservation efforts aimed at mitigating species diversity loss while addressing human diseases.

Phytochemical Research and Anti-Inflammatory Activities of the Ethanol Extract from Anoectochilus Roxburghii (Wall.) Lindl

Anoectochilus roxburghii is a well-known and valuable traditional Chinese herb due to various medicinal and functional benefits. In-depth investigation is necessary to discover active ingredients and expand its application. In this study, four new compounds (1-4) along with ten known compounds (5-14) were isolated from the ethanol extract of A.roxburghii. Their structures were elucidated by spectroscopic data interpretation. The isolates were screened for their inhibitory activities on the production of NO in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. Among them, compounds 5, 6, 9, 10, 12, 13 and 14 exhibited significant anti-inflammatory activity through inhibiting the release of NO.

Two New Seco-Labdane Diterpenoids from the Leaves of Callicarpa nudiflora

Two new seco-labdane diterpenoids, nudiflopene N (1) and nudiflopene O (2), and four known compounds were isolated from the leaves of Callicarpa nudiflora. The structures of the new compounds were established by 1D-, 2D-NMR, and HR-ESI-MS spectral analyses. Compounds 1–3 showed inhibitory activities on lipopolysaccharide-induced nitric oxide (NO) production in RAW264.7 cells, and new compounds 1–2 exhibited more potent inhibitory activity than compound 3. The cytotoxicity of compounds 1–3 against human hepatocellular carcinoma HepG2 cells and human gastric carcinoma SGC-7901 cells were evaluated, while all of them exhibited no cytotoxicity.