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Two new flavonoid glycosides, 2′,4′-dihydroxydihydrochalcone-4-O-β-d-glucopyranoside (1) and medicarpin-3-O-β-d-apiofuranosyl (1 → 2)-β-d-glucopyranoside (2), together with 34 known flavonoids were isolated from the 75% EtOH extract of the dried roots of Glycyrrhiza uralensis Fisch. Their structures were elucidated on the basis of spectroscopic analyses. The flavonoids were classified into ten sub-types, namely, dihydrochalcone (1), pterocarpans (2–4), flavones (5–6), flavanones (7–11), chalcones (12–15), retro-chalcones (16–18), isoflavans (19–21), isoflavones (22–28), 3-arylcoumarins (29–30), and coumestans (31–36). The isolated flavonoids were evaluated for in vitro hepatoprotective activity against d-galactosamine-induced toxicity in human hepatoma HepG2 cells.

Upon one-pot reaction of the mono-imine Schiff-base precursor HL1 (HL1 = (E)-2-((2-aminophenylimino)methyl)-4,6-di-tert-butyl-phenol), Ni(OAc)2·4H2O and salicylaldehyde, the Ni2 +-template mechanism to the in situ formed nonsymmetrical Salen-type Schiff-base H2L-based complex [Ni(L)] (1) is identified with an intermediate of [Ni(L1)(μ1-OAc)]. Moreover, within following nonsymmetrical Salen-type Schiff-base Ni2 + complexes, the complex 1 is shown to effectively catalyze the solution polymerization of styrene in the presence of MAO (methylaluminoxane).

An exploration we carried out for isolating nitric oxide (NO) inhibitors from the rhizomes of Curcuma phaeocaulis afforded one new salvialane-type sesquiterpene, phasalvione (1), two novel nor-sesquiterpenes, phaeocaudione (2) and phaeocauone (3), one aromatic acid 3-methyl-4-(3-oxo-butyl)-benzoic acid (4), two γ-elemene-type sesquiterpenes, 8β(H)-elema-1,3,7(11)-trien-8,12-lactam (5) and 8β-methoxy-isogermafurenolide (6), one eudesmane-type sesquiterpene, phaeusmane I (7), and one cyclic diarylheptanoid, phaeoheptanoxide (8). Their structures were established based on extensive spectroscopic analysis. The absolute configurations of compounds 1 and 2 were assigned using the circular dichroism data of the [Rh2(OCOCF3)4] complex, and the absolute configuration of 1 was further established by single crystal X-ray crystallography. It is noteworthy that compounds 5–7 were racemates analyzed by chiral HPLC. Furthermore, the inhibitory effects of the isolated compounds on nitric oxide production in LPS-activated macrophages were evaluated. Compounds 1, 3 and 4 showed strong inhibitory activities on NO production with IC50 values of 7.46 ± 0.69, 2.35 ± 0.17 and 3.49 ± 0.31 μM, respectively. A plausible biosynthetic pathway for 1–4 in C. phaeocaulis was also discussed.

Ten new guaiane-type sesquiterpenes (1-10), phaeocaulisins A-J, and 18 known guaiane derivatives were isolated from rhizomes of Curcuma phaeocaulis. Their structures were established on the basis of extensive spectroscopic analyses, X-ray crystallographic analysis, and comparison with literature data. Compound 10 is the first example of a norsesquiterpene with this unusual skeleton isolated from the genus Curcuma. All of the isolated compounds were tested for inhibitory activity against LPS-induced nitric oxide production in RAW 264.7 macrophages. Compounds 1, 2, 20, and 22-24 inhibited nitric oxide production with IC50 values less than 2 μM. Preliminary structure-activity relationships for these compounds are discussed.

Nine new monoterpene glycosides (1-9), together with 18 known compounds were obtained from the n-butanol soluble fraction of ethanol extract from Paeonia suffruticosa Andrews. Their structures were determined on the basis of chemical methods and spectroscopic data. The inhibitory effects of these compounds (except compound 6) on nitric oxide (NO) production in lipopolysaccharide-activated macrophages were evaluated. Compounds 1, 21, 23, 25, and 27 showed strong inhibitory activity on NO production with IC(50) values of 31.25, 36.13, 12.41, 6.87, and 41.94 μM, respectively.

Paeonol, a major component of Paeonia suffruticosa Andrews, is used in clinical situations in China as a natural anti-inflammatory agent. The aim of the present study is to investigate the metabolism of paeonol in humans. Six metabolites were isolated from human urine after oral administration of paeonol, and their structures were elucidated as resacetophenone (M1), resacetophenone-2-O-sulfate (M2), 2-hydroxy-4-methoxyacetophenone-5-O-sulfate(M3), 2-hydroxy-4-methoxyacetophenone-5-O-glucopyranuronoside (M4), 2-hydroxyacetophenone-4-O-glucopyranuronoside (M5) and 2,5-dihydroxy-4-methoxyacetophenone(M6) by a series of analyses involving mass spectrometry, (1)H NMR, (13)C NMR and NOESY spectra. In addition, three more metabolites 2,4-dihydroxyacetophenone-5-O-sulfate (M7), paeonol-2-O-glucopyranuronoside (M8) and paeonol-2-O-sulfate (M9), were identified in human urine by using a UPLC/Q-TOF-MS/MS method. This is the first study of paeonol metabolism in humans. Based on the identified metabolites, possible metabolic pathways of paeonol in humans are proposed. Paeonol is metabolized mainly by hydroxylation and demethylation to give the corresponding phase I metabolites, M1, M6 and 2,4,5-trihydroxyacetophenone, and which then underwent conjugation with glucuronic acid or sulfuric acid to form phase II metabolites.

An exploration we carried out for isolating nitric oxide (NO) inhibitors from the rhizomes of Curcuma phaeocaulis afforded one new salvialane-type sesquiterpene, phasalvione (1), two novel nor-sesquiterpenes, phaeocaudione (2) and phaeocauone (3), one aromatic acid 3-methyl-4-(3-oxo-butyl)-benzoic acid (4), two γ-elemene-type sesquiterpenes, 8β(H)-elema-1,3,7(11)-trien-8,12-lactam (5) and 8β-methoxy-isogermafurenolide (6), one eudesmane-type sesquiterpene, phaeusmane I (7), and one cyclic diarylheptanoid, phaeoheptanoxide (8). Their structures were established based on extensive spectroscopic analysis. The absolute configurations of compounds 1 and 2 were assigned using the circular dichroism data of the [Rh2(OCOCF3)4] complex, and the absolute configuration of 1 was further established by single crystal X-ray crystallography. It is noteworthy that compounds 5–7 were racemates analyzed by chiral HPLC. Furthermore, the inhibitory effects of the isolated compounds on nitric oxide production in LPS-activated macrophages were evaluated. Compounds 1, 3 and 4 showed strong inhibitory activities on NO production with IC50 values of 7.46 ± 0.69, 2.35 ± 0.17 and 3.49 ± 0.31 μM, respectively. A plausible biosynthetic pathway for 1–4 in C. phaeocaulis was also discussed.

Three pairs of monoterpene glycosides (1-6), of which compounds 1, 3, and 4 as new compounds, together with one new monoterpene (7) were obtained from the ethanol extract of Paeonia suffruticosa Andrews. Their structures were determined on the basis of chemical methods and spectral data. On this basis, the spectral characteristics of three pairs of monoterpene glycosides were also discussed. The inhibitory effects of isolated compounds on nitric oxide (NO) production in lipopolysaccharide-activated macrophages were evaluated, and NO production was suppressed significantly by compounds 4-7.

The synthesis of dinitrochalcones was studied by using ultrasonic irradiation in the presence of potassium carbonate as a catalyst, which provided a conventional procedure with the advantages of a short reaction period and as high as 90% product yield.