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Ten new highly oxidized monomeric (1–8) and dimeric guaianolides (9and 10), along with two known guaianolide derivatives (11and 12), were isolated from the aerial parts of Chrysanthemum indicumusing a bioassay-guided fractionation procedure. The new compounds were characterized by the basic analysis of the spectroscopic data obtained, and the absolute configurations were determined by both empirical approaches and ECD calculations. Inhibitory effects of 1–12on nitric oxide production were investigated in lipopolysaccaride (LPS)-mediated RAW 264.7 cells, and most of them (1–8and 11) displayed IC50values in the range 1.4–9.7 μM. Moreover, a mechanistic study revealed that the potential anti-inflammatory activity of compound 1appears to be mediated via suppression of an LPS-induced NF-κB pathway and down-regulation of MAPK activation.

Peyronellones A and B (1and 2), a pair of rare tetracyclic caged adducts of azaphilone with pyruvic acid, along with four new analogues (3–6), were isolated from solid cultures of the endophytic fungus Peyronellaea glomerata. Their structures were elucidated through spectroscopic analysis, and their absolute configurations were unambiguously determined by a combination of single-crystal X-ray crystallography, Rh2(OCOCF3)4-induced ECD experiments, ECD calculations, and modified Mosher methods. Compound 2(5 μM) was found to have a significant hypoxia-protective effect that improved the survival rate of hypoxia/reoxygenation-treated human umbilical vein endothelial cells from 35% to 70%, which was equal to the potency of the positive control, verapamil. Flow cytometry analysis suggested 2could inhibit H/R-induced late-stage apoptosis of this cell line.

The isolation of the new polycyclic polyprenylated acylphloroglucinols uraliones A–K (1–11) together with five known analogues (12–16) from a whole Hypericum uralumplant was reported. The structures of these compounds were established through spectroscopic methods, and a single-crystal X-ray diffraction analysis was used to confirm the absolute configuration of 1. The protective effects of the isolates against corticosterone-induced PC12 cell injury were assessed. Except for compound 9, all tested compounds exhibited significant protective effects against induced injury in PC12 cells. Uralodin A (14), orally administered in doses of 13 and 26 mg/kg, exhibited antidepressant-like activity in the tail suspension and forced-swimming tests in mice.

During an ongoing exploration of potential anti-inflammatory agents from medicinal plants, eight new arylalkenyl α,β-unsaturated δ-lactones, cryptoconcatones A–H (1–8), and two unusual arylalkenyl α,β-unsaturated γ-lactones, cryptoconcatones I and J (9and 10), were identified from the leaves and twigs of Cryptocarya concinna.The structures of these compounds were established based on spectroscopic data (MS, 1D/2D NMR), and their absolute configurations were determined with Riguera’s method, the modified Mosher’s method, chemical derivatization, and the Snatzke chirality rule. Compounds 4–6and 8–10showed inhibitory activity toward nitric oxide (NO) production in lipopolysaccharide-induced RAW 264.7 macrophages, particularly compounds 4and 8–10, with IC50values of 3.2, 4.2, 3.4, and 7.5 μM, respectively.

Chuktabularins E−T (1−16), 16 new 16-norphragmalin limonoids, together with four known compounds, chuktabularins A−D, were isolated from the stem bark of Chukrasia tabularisvar. velutina. These compounds possess a biosynthetically extended propionyl or acetyl group at C-15 and a characteristic ketal moiety between the limonoid skeleton and the acyl substituent at C-15. The structures of these compounds were established on the basis of detailed spectroscopic analysis, and that of 1was confirmed by a single-crystal X-ray diffraction experiment, representing the first verification of the skeleton of 16-norphragmalin limonoids. Chuktabularins K−O (7−11) were found to be the first 19-acetoxylated 16-norphragmalin limonoids. Variable-temperature 1H NMR experiments suggested that 7exists as an equilibrium mixture of conformational isomers in solution. The absolute configuration of 5was determined by the CD exciton chirality method on its 11,12-di-p-chlorobenzoate (5a), and those of 1−4and 6−16were proposed by correlating with 5spectroscopically and biogenetically.