To identify monoterpenoid small molecules, a comprehensive phytochemical exploration of the root bark of Paeonia ostii T. Hong & J. X. Zhang was carried out, resulting in the isolation and characterization of two new monoterpenoid glycosides, designated monoterpesides A and B (1 and 2), together with four known monoterpenoid glycosides (3-6). The structures of the new compounds were established by comprehensive spectroscopic analyses, including UV, HRESIMS, IR, alongside both 1D and 2D NMR spectroscopy. To confirm the molecular structures, the identified structural constituents and chemical formulas were meticulously compared with those of previously reported compounds. In addition, the cytotoxic activities of the isolated compounds and their inhibitory effects on nitric oxide production were evaluated. Notably, monoterpeside A demonstrated moderate cytotoxic activity against HepG2 and HL-60 tumor cell lines, at the concentrations tested with the IC50 values of 13.40 and 28.98 μM, respectively. Furthermore, the inhibition assay revealed that monoterpeside A exhibited mild inhibitory activity against nitric oxide production in the RAW 264.7 macrophage cells, with an inhibition rate of 34.9% under the tested conditions.
Two new 2-(2-phenylethyl)chromone dimers (1 and 2), together with a known one (3), were isolated from the ethanol extract of agarwood produced from Aquilaria sinensis ‘Reke 1’. The structures of compounds 1 and 2 were precisely elucidated on the basis of HR-ESI-MS, 1D and 2D NMR, ECD, as well as by comparison with the literature data. All compounds were evaluated for their inhibition effects on NO production in LPS-stimulated RAW264.7 cells. Compounds 1, 2 and 3 exhibited anti-inflammatory activity with IC50 values of 13.04 ± 0.52 μM, 10.50 ± 0.55 μM and 11.38 ± 0.41 μM, respectively (quercetin as positive control, IC50 10.12 ± 0.49 μM).
10-Hydroxycamptothecin (HCPT), a naturally occurring camptothecin (CPT) derivative in Camptotheca acuminata, is significant to the pharmaceutical industry, yet its efficient acquisition remains challenging. Given that the accumulation of CPT-related metabolites, including HCPT, can vary among tissues and developmental stages, we aimed to characterize changes in HCPT accumulation across floral developmental stages. The floral units (FUs) were classified into two types and further categorized into eight developmental stages based on their morphological characteristics. HCPT and CPT contents were quantified at each stage to evaluate developmental-stage-dependent changes in CPT-related metabolite accumulation, and subsequently RNA-seq analysis was performed using representative stages. HCPT levels increased from the bud to the late female stage but decreased in the fruiting stage. RNA-seq analysis provided supportive information for understanding developmental-stage-dependent changes in HCPT accumulation. Among the FU developmental stages examined, the late female stage (T5) showed the highest HCPT accumulation under the conditions of the present study.
Two new monoterpene indole alkaloids, alstonmairine A and B (1–2), were isolated from the branches and leaves of Alstonia mairei. Their structures were elucidated using a combination of spectroscopic and computational chemistry approaches. Compound 1 markedly alleviated the lipopolysaccharide (LPS)-induced injury in N9 cells at concentrations of 10 μM and 50 μM.
Phytochemical study on the fruiting bodies of Sarcodon scabrosus yielded one new cyathane diterpenoid, scabronine N (1), one known analogue (2), and one known steroid (3). The structure of compound 1 was elucidated by extensive spectroscopic analysis, and its absolute configuration was determined by biosynthetic comparison with related cyathane derivatives. All isolates were evaluated for neurotrophic activity using a PC12 cell differentiation model. However, none of the compounds showed significant neuritogenic effects at 25 μM. This work enriches the chemical diversity of cyathane diterpenoids and provides supplementary chemical and biological information for S. scabrosus.
