Abietane diterpenes from the twigs and leaves of Cephalotaxus oliveri Mast. with antitumor activity

Cephaliverins A-D, four new lignans from Cephalotaxus oliveri Mast

Four new lignans named cephaliverins A-D (1-4), along with seven known analogues (5-11), were isolated from Cephalotaxus oliveri Mast. Their structures were elucidated on the basis of HR-ESI-MS and NMR analyses, and their absolute configurations were determined by ECD comparison. Cephaliverin A (1), herpetotriol (5) and hedyotol A (6) exhibited moderate antitumor activity against HepG2 and A549 cell lines.

Supercritical CO2 Extraction of Terpenoids from Indocalamus latifolius Leaves: Optimization, Purification, and Antioxidant Activity

This study aimed to investigate the efficacy of supercritical CO2 (SC-CO2) extraction in enhancing the extraction rate, purity, and antioxidant activity of Indocalamus latifolius (Keng) McClure (Poaceae) leaf terpenoids (ILLTs). Crude extracts obtained from leaves were subjected to qualitative and quantitative analyses, revealing neophytadiene, phytol, β-sitosterol, β-amyrone, squalene, and friedelin as the primary terpenoid constituents, identified through gas chromatography-mass spectrometry (GC-MS). Compared with steam distillation extraction (SD), simultaneous distillation extraction (SDE), ultra-high pressure-assisted n-hexane extraction (UHPE-Hex), ultra-high pressure-assisted ethanol extraction (UHPE-EtOH), ultrasound-assisted n-hexane extraction (UE-Hex), and ultrasound-assisted ethanol extraction (UE-EtOH), SC-CO2 exhibited a superior ILLT extraction rate, purity, and antioxidant activity. Scanning electron microscopy (SEM) observations of the residues further revealed more severe damage to both the residues and their cell walls after SC-CO2 extraction. Under optimal parameters (4.5 h, 26 MPa, 39 °C, and 20% ethyl alcohol), the ILLT extraction rate with SC-CO2 reached 1.44 ± 0.12 mg/g, which was significantly higher than the rates obtained by the other six methods. The subsequent separation and purification using WelFlash C18-l, BUCHI-C18, and Sephadex LH-20 led to an increase in the purity of the six terpenoid components from 12.91% to 93.34%. Furthermore, the ILLTs demonstrated cytotoxicity against HepG2 cells with an IC50 value of 148.93 ± 9.93 μg/mL. Additionally, with increasing concentrations, the ILLTs exhibited an enhanced cellular antioxidant status, as evidenced by reductions in both reactive oxygen species (ROS) and malondialdehyde (MDA) levels.

Diterpenolignans and cephalotane diterpenoids from Cephalotaxus oliveri mast. with antitumor activity

Four undescribed naturally diterpenolignans, and two cephalotane diterpenoids, along with seven known compounds, including two pairs of enantiomers, were isolated from the twigs and leaves of Cephalotaxus oliveri Mast. Their structures were elucidated via spectroscopic data interpretation, chiral-phase HPLC analysis, NMR calculations, and electronic circular dichroism analysis. All the isolated compounds were evaluated for their cytotoxic activities against three kinds of human tumor cell lines. Among them, compound 8 exhibited the most potent activities against MCF-7, HepG2 and A549 cell lines with IC50 values of 2.83, 4.75 and 2.77 μM, respectively.

Cytotoxic xanthones from Garcinia pedunculata fruits

Eight previously undescribed and seven known xanthones were isolated from the fruits of Garcinia pedunculata Roxb. The structures were identified by a variety of spectroscopic methods as well as by comparison with the literature. The isolates showed appreciable cytotoxicity against three human tumor cell lines (HepG2, A549, and MCF-7). Pedunculaxanthone G exhibited inhibitory activities with IC50 values of 12.41, 16.51, and 15.45 μM against the cancer cell lines and induced cell apoptosis in HepG2 cells.

Abietane diterpenoids and iridoids from Caryopteris mongolica

Six new abietane diterpenoids (1-6) and five undescribed iridoids (7-11) have been isolated from the aerial parts of Caryopteris mongolica. The intricate structural characterization of these compounds was meticulously undertaken using an array of advanced spectroscopic techniques. This process was further enhanced by the application of DP4+ probability analyses and electronic circular dichroism (ECD) calculations. Following isolation and structural elucidation, the cytotoxicity of these compounds was evaluated. Among them, compound 3 stood out, displaying significant cytotoxic activity against HeLa cells with an IC50 value of 7.83 ± 1.28 μmol·L-1. Additionally, compounds 1, 2, 4, 9, and 10 manifested moderate cytotoxic effects on specific cell lines, with IC50 values ranging from 11.7 to 20.9 μmol·L-1.

Abietane diterpenoids with anti-inflammatory activities from Callicarpa bodinieri

Nine undescribed abietane diterpenoids (1-9) and eleven known abietane analogs (10-20) were isolated from Callicarpa bodinieri. Their structures were characterized by interpreting spectroscopic data, X-ray crystallography, and ECD analysis. The anti-inflammatory activities of these compounds were tested by evaluation of their inhibitory effect on NO production by lipopolysaccharide in RAW 264.7 macrophages, and compounds 3 and 8 exhibited potent anti-inflammatory activities with IC50 values of 36.35 ± 1.12 and 37.21 ± 0.92 μM. The western blotting studies demonstrated that compound 3 inhibited the expression of nitric oxide synthase and p65 that involved in the NF-κB pathway.

Stilbenes with potent cytotoxicity from the seedcases of Paeonia suffruticosa Andrews

Stilbenes (based on the 1,2-diphenylethylene skeleton) are a class of plant polyphenols with rich structural and bioactive diversity. Twenty-six stilbenes, including five undescribed compounds (7,8-dioxy-4,3',5'-trihydroxystilbene, trans-13'-methoxygnetin H, suffruticosol E, paestibenetrimerols A and B), were isolated from the seedcases of Paeonia suffruticosa Andrews. Their structures were elucidated by spectroscopic analyses and comparison with previously reported data. The absolute configurations of trans-13'-methoxygnetin H, suffruticosol E, paestibenetrimerols A and B were assigned from their respective electronic circular dichroism (ECD) spectra. Additionally, the structures of known compounds suffruticosols A, B and rockiol B were revised and the absolute configurations of them, and along with (+)-davidiol A, were also further determined by ECD. The isolated compounds, trans-gnetin H, cis-gnetin H and suffruticosol E, were found to have potent cytotoxicity against the DU-145 and MDA-MB-231 cell lines with IC₅₀ values of 4.89-8.61 μM. The preliminary antitumor structure-activity relationship of these stilbenes is discussed as well.

Abietane diterpenoids from Phlegmariurus carinatus and their biological activities

Five undescribed abietane diterpenoids, along with eight known analogs, were isolated from Phlegmariurus carinatus. Their structures were unambiguously elucidated by extensive analysis of spectroscopic data and comparison between the literature. The absolute configuration of phlecarinatone C was determined by evaluating ECD spectra. Four undescribed abietane diterpenoids and eight known analogs were tested for their neuroprotective and cytotoxic activities, separately. Teuvincenone C showed potential neuroprotective effect against Hemin-induced HT22 cell damage. Importantly, phlecarinatone C showed pronounced cytotoxic effect against U251 cells in vitro assays. The biological evaluation revealed that phlecarinatone C could inhibit proliferation, migration, and invasion in a concentration-dependent manner of U251 cells. Meanwhile, phlecarinatone C effectively reversed epithelial-to-mesenchymal transition (EMT) and promoted U251 cells apoptosis via a mitochondrial apoptotic pathway. Taken together, phlecarinatone C might be a valuable candidate for anti-metastatic agents against glioblastoma treatment.