Sesquiterpenes from Wikstroemia lungtzeensis with anti-neuroinflammatory effects.

An anti-neuroinflammatory activities-guided phytochemical research of Wikstroemia lungtzeensis was performed for the first time. Three undescribed carotane-type sesquiterpenes, excoecafolinols C-E (1-3), and nine known sesquiterpene derivatives were isolated from the effective ethyl acetate extract of W. lungtzeensis. Their structures were determined based on multiple spectroscopic techniques and electronic circular dichroism (ECD) spectra. Furthermore, the anti-neuroinflammatory activities of the identified compounds were evaluated in lipopolysaccharide-stimulated BV-2 cells. Among them, six components (1, 2, 4, 7, 11, 12) exhibited significant inhibitory effects on nitric oxide (NO) production, with IC50 values ranging from 10.48 to 49.41 µM (positive control minocycline, IC50 53.20 µM). Carotane-type sesquiterpenes (1, 2, 4) with high content and significant inhibitory effects, are considered to be major active ingredients of W. lungtzeensis, which might serve as potential therapeutic agents for neurodegenerative diseases.

Anti-HIV Tigliane-Type Diterpenoids from the Aerial Parts of Wikstroemia lichiangensis.

Tigliane-type diterpenoids have attracted much attention in drug discovery since they have been reported to exhibit remarkable biological effects, such as tumor-promoting, antineoplastic, and anti-HIV activities. In continuing our efforts to discover novel biologically important diterpenoids from Wikstroemia species, Wikstroemia lichiangensis was investigated phytochemically for the first time. As a result, four new (1-4) and one known (5) tigliane-type diterpenoid were isolated, and their structures were elucidated by spectroscopic data analysis. Tiglianes (1-5) showed potent anti-HIV activity against HIV-1 infection of MT4 lymphocytes with IC50 values of 1.1-65.4 nM.

LC-MS Identification, Isolation, and Structural Elucidation of Anti-HIV Tigliane Diterpenoids from Wikstroemia lamatsoensis.

Structurally diverse tigliane diterpenoids have drawn significant research interest for drug discovery over many decades. Using LC-MS-guided fractionation and separation, the first phytochemical investigation on Wikstroemia lamatsoensis led to the isolation of eight tiglianes (1-8), including two new compounds, wikstrocin D (1) and wikstrocin E (2). The new structures were elucidated based on extensive physicochemical and spectroscopic analyses. The characteristic ESIMS/MS fragmentations of tiglianes 1-8 were also summarized. Among the isolated tiglianes, three compounds (8, 5, and 7) showed the most potent anti-HIV activity, with IC50 values of 0.18, 3.8, and 12.8 nM, respectively.

Anti-HIV Tigliane Diterpenoids from Wikstroemia scytophylla.

During a chemical investigation of Wikstroemia scytophylla, three new [wikstrocins A-C (1-3)] and three known tigliane diterpenoids (4-6) were isolated. The structures of the new compounds were elucidated from extensive physiochemical and spectroscopic analysis. The correlations between the ECD Cotton effects and B ring structures of tiglianes were also evaluated. The isolated compounds were assessed for their anti-HIV activity against HIV-1 infection of MT4 cells, and two compounds (4 and 6) showed potent anti-HIV activity with IC50 values of 3.8 and 12.8 nM, respectively.

Identification of anti-HIV macrocyclic daphnane orthoesters from Wikstroemia ligustrina by LC-MS analysis and phytochemical investigation.

Macrocyclic daphnane orthoesters (MDOs) have attracted significant research interest for the drug discovery to cure HIV infection based on the "Shock and Kill" strategy. In the present study, the first chemical study on Wikstroemia ligustrina (Thymelaeaceae) was carried out by LC-MS analysis and phytochemical investigation. Nine daphnane diterpenoids (1-9) including seven MDOs were detected by LC-MS analysis. Further phytochemical investigation resulted in the isolation and structural elucidation of five daphnanes (1, 2, 5, 8, and 9) with potent anti-HIV activity. Taking the isolated MDO (1) as a model compound, the MS/MS fragmentation pathway was also elucidated.