Isolation, Structure Elucidation, and Antiproliferative Activity of Butanolides and Lignan Glycosides from the Fruit of Hernandia nymphaeifolia.

Seven new butanolides, peltanolides A-G (1-7), and two lignan glucosides, peltasides A (8) and B (9), along with eleven known compounds, 10-20, were isolated from a crude CH3OH/CH2Cl2 (1:1) extract of the fruit of Hernandia nymphaeifolia (Hernandiaceae). The structures of 1-9 were characterized by extensive 1D and 2D NMR spectroscopic and HRMS analysis. The absolute configurations of newly isolated compounds 1-9 were determined from data obtained by optical rotation and electronic circular dichroism (ECD) exciton chirality methods. Butanolides and lignan glucosides have not been isolated previously from this genus. Several isolated compounds were evaluated for antiproliferative activity against human tumor cell lines. Lignans 15 and 16 were slightly active against chemosensitive tumor cell lines A549 and MCF-7, respectively. Furthermore, both compounds displayed significant activity (IC50 = 5 µM) against a P-glycoprotein overexpressing multidrug-resistant tumor cell line (KB-VIN) but were less active against its parent chemosensitive cell line (KB).

Corymbulosins I-W, Cytotoxic Clerodane Diterpenes from the Bark of Laetia corymbulosa.

The isolation studies of a crude MeOH/CH2Cl2 (1:1) extract (N005829) of the bark of Laetia corymbulosa yielded 15 new clerodane diterpenes, designated corymbulosins I-W (1-15), as well as four known diterpenes, 16-19. The structures of 1-15 were characterized on the basis of extensive 1D and 2D NMR and HRMS analyses. The absolute configurations of newly isolated compounds 1-15, as well as known 16-19, which were reported previously with only relative configurations, were determined through ECD experiments, X-ray analysis, chemical methods, including Mosher esterification, and comparison of their spectroscopic data. The isolated compounds were evaluated for cytotoxicity against human cancer cell lines. Flow cytometric and immunocytochemical observations of cells treated with cytotoxic clerodanes demonstrated that the chromatin was fragmented and dispersed with formation of apoptotic microtubules.

New sesquiterpene lactones, vernonilides A and B, from the seeds of Vernonia anthelmintica in Uyghur and their antiproliferative activities.

A new guaianolide sesquiterpene lactone, vernonilide A (1), and a new elemanolide sesquiterpene lactone, vernonilide B (2), were isolated from the seeds of Vernonia anthelmintica, together with three known elemanolide sesquiterpene lactones (3-5). The structures of the isolated compounds were elucidated on the basis of physicochemical evidences. Compounds 1, 3, and 4 showed strong antiproliferative activities against three human cancer cell lines (A549, HeLa, and MDA-MB-231), with IC50 values ranging from 0.10 to 1.00µM. In addition, 5 exhibited significant antiproliferative activities against HeLa and MDA-MB-231 cells, with IC50 values ranging from 1.90 to 2.20µM. The antiproliferative activities of the acetyl derivatives 6 and 7 prepared from 4 and 3, respectively, against the three cell lines were 4-10-fold weaker than the original activities.

Isopimarane diterpenoids from Kaempferia pulchra rhizomes collected in Myanmar and their Vpr inhibitory activity.

Viral protein R (Vpr), an accessory gene of HIV-1, plays important roles in viral pathogenesis. Screening of Myanmar medicinal plants that are popular as primary treatments for HIV/AIDS and for HIV-related problems revealed the potent anti-Vpr activity of the CHCl3-soluble extract of Kaempferia pulchra rhizomes, in comparison with that of the positive control, damnacanthal. Fractionation of the active CHCl3-soluble extract led to the identification of 30 isopimarane diterpenoids, including kaempulchraols A-W (1-23). All isolates were assayed for anti-Vpr activity against TREx-HeLa-Vpr cells, in which Vpr expression is tightly regulated by tetracycline. Kaempulchraols B (2), D (4), G (7), Q (17), T (20), U (21), and W (23) exhibited potent anti-Vpr activity, at concentrations ranging from 1.56 to 6.25µM. The structure-activity relationships of the active kaempulchraols suggested that the presence of a hydroxy group at C-14 in an isopimara-8(9),15-diene skeleton and the presence of an acetoxy group at C-1 or C-7 in an isopimara-8(14),15-diene skeleton are the critical factors for the inhibitory effects against TREx-HeLa-Vpr cells.

Kaempulchraols A-H, Diterpenoids from the Rhizomes of Kaempferia pulchra Collected in Myanmar.

Eight new diterpenoids, kaempulchraols A-H (1-8), along with five known analogues were isolated from the CHCl3-soluble extract of rhizomes of Kaempferia pulchra of Myanmar. The structures of these compounds were elucidated using extensive spectroscopic techniques including X-ray diffraction analysis. All the isolates were tested for their antiproliferative activity against a panel of five human cancer cell lines (A549, human lung cancer; HeLa, human cervix cancer; PANC-1 and PSN-1, human pancreatic cancer; MDA-MB-231, human breast cancer) and TIG-3, normal human primary fibroblast cells. Kaempulchraol F (6) exhibited weak activity against the human pancreatic PSN-1 cell line with an IC50 value of 12.3 µM.

Kaempulchraols P-T, Diterpenoids from Kaempferia pulchra Rhizomes Collected in Myanmar.

The isolation of the oily fraction obtained from the CHCl3-soluble extract of the rhizomes of Kaempferia pulchra afforded five new isopimarane diterpenoids, kaempulchraols P-T (1-5), along with two known analogues. The structures were elucidated using spectroscopic techniques, including 2D NMR spectroscopy.