Eudesmane sesquiterpenoids with inhibitory effects on NO production from Artemisia princeps.

Five undescribed eudesmane methyl esters (1-5), three undescribed eudesmane-12,6-olides (6-8), and 21 known analogues (9-29) were isolated from the aerial part of Artemisia princeps Pamp. Their structures were established by detailed analysis of the NMR and HRESIMS data. The absolute configurations of 1-8 were determined based on single-crystal X-ray diffraction analysis and ECD calculations. Moreover, the inhibitory effects on LPS-induced NO production in BV-2 microglial cells of all the isolated compounds were assessed. Except for compounds 2, 4, 10, and 11, the others showed significant inhibitory activities, with IC50 values of 0.73-18.66 µM, wherein the potential structure-activity relationship was also discussed.

Sesquiterpenes and diterpenes from Euphorbia thymifolia.

One new pseudoguaianolide (1), one new megastigmane (6), and one new ent-abietane diterpene (9), together with seven known compounds (2-5, 7, 8, and 10) were isolated from the aerial parts of Euphorbia thymifolia. The structures of the new compounds and their relative configurations were determined by spectroscopic data analysis. The absolute configurations of compounds 1, 6, and 9 were determined by single-crystal X-ray crystallographic analysis, modified Mosher's method and calculated ECD experiment, respectively. All compounds were tested for their inhibitory effects against LPS-induced NO production in BV-2 microglial cells, and pseudoguaianolides (1-5) showed significant activity with IC50 values of 0.41-15.32 µM.

[Study on chemical constituents of stems and leaves of Sapium discolor].

Seventeen compounds were isolated from the 95% ethanol extract of the stems and leaves of Sapium discolor by using various chromatographic techniques,including silica gel,Sephadex LH-20,MCI,ODS,and semi-preparative HPLC. Their structures were elucidated as sapiumin F( 1),kadsulignan C( 2),ciwujiatone( 3),ethylbrevifolin carboxylate( 4),7-hydroxy-8-methoxycoumarin( 5),fraxetin( 6),fraxidin( 7),isofraxidin( 8),6,7,8-trimethoxycoumarin( 9),5,6,7,8-tetramethoxycoumarin( 10),8-hydroxy-5,6,7-trimethoxycoumarin( 11),3,3'-di-O-methylellagic acid( 12),3,3',4'-tri-O-methylellagic acid( 13),3'-methoxyellagic acid 4'-O-α-rhamnopyranoside( 14),4,5-didehydro-chebulic acid triethyl ester( 15),ent-kaurane-3-oxo-16α,17-diol( 16),and abscisic acid( 17) by spectroscopic data. Compound 1 is a new compound. Except for compounds 4,11,and 13,the remaining compounds were isolated from this plant for the first time. All the isolates were evaluated for their in vitro antineuroinflammatory activities,and the results showed that compounds 6 and 15 significantly inhibited nitric oxide production in lipopolysaccharide-induced BV-2 microglial cells,with IC50 values of 6. 06 and 6. 05 µmol·L-1,respectively.

Coumarinolignoids and lignanoids from the stems and leaves of Sapium discolor.

Two new coumarinolignoids, sapiumins D (1) and E (2), a new lignanoid, lariciresinol 9'-benzoate (3), together with six known coumarinolignoids (4-9) and eight known lignanoids (10-17), were isolated from the stems and leaves of Sapium discolor. The structures of the isolated compounds were elucidated by extensive spectroscopic methods, including NMR, MS, and single crystal X-ray diffraction experiments. Compounds 5, 10, 11, and 13 significantly inhibited nitric oxide production in lipopolysaccharide-induced BV-2 microglial cells, with IC50 values in the range of 2.13-11.37 µM.

New terpenoid and phenylpropanoid glycosides from Tinospora sinensis.

Two new cadinane sesquiterpene glucosides (1, 2), two new phenylpropanoid glycosides (3, 4), and two new diterpenoid glucosides (5, 6), as well as 6 known compounds were isolated from the stems of Tinospora sinensis. The structures of these compounds were elucidated by extensive spectroscopic analysis and chemical methods. The absolute configuration of compound 1 was determined by timedependent density functional theory (TDDFT) electronic circular dichroism (ECD) calculations and in situ dimolybdenum CD method. All the isolated compounds except for compounds 7, 11 and 12 were evaluated for their anti-neuroinflammatory effect by inhibiting the nitric oxide (NO) production in lipopolysaccharide (LPS)-activated murine BV-2 microglial cells, and compound 4 showed anti-neuroinflammatory activity with IC50 values 42.90 µM in vitro assay.

Coumarinolignoids and Taraxerane Triterpenoids from Sapium discolor and Their Inhibitory Potential on Microglial Nitric Oxide Production.

Seventeen compounds, including three new pairs of coumarinolignoid enantiomers, (7' S,8' S)-sapiumins A-C (1a-3a) and (7' R,8' R)-sapiumins A-C (1b-3b), six new taraxerane triterpenoids, sapiumic acids A-F (4-9), and five known taraxerane triterpenoids (10-14), were isolated from an ethanol extract prepared from the stems and leaves of Sapium discolor. The structures of 1-9 and their relative configurations were determined by spectroscopic data analysis, and the absolute configurations of the coumarinolignoids 1a/1b-3a/3b and triterpenoids 6-9 were assigned using experimental and calculated ECD data. Compounds 1a/1b-3a/3b are the first coumarinolignoids to be reported from the genus Sapium. Among all the isolates, compounds 1b, 2a/2b, 3a/3b, and 6-9 inhibited nitric oxide production in lipopolysaccharide-stimulated BV-2 microglial cells, with IC50 values of 1.7-15.3 µM.

Clerodane Diterpenoid Glucosides from the Stems of Tinospora sinensis.

Ten new clerodane diterpenoid glucosides (1-10) and three known analogues (11-13) were isolated from an EtOAc extract of the stems of Tinospora sinensis. Spectroscopic analyses and chemical methods were used to elucidate the structures of these isolates. The absolute configurations of tinosinenosides A-C (1-3) were established by using experimental and calculated ECD data. Their cytotoxicity against the human epithelioid cervical carcinoma (HeLa) cell line and the nitric oxide production inhibitory activity of lipopolysaccharide-activated N9 microglial cells were tested. 1-Deacetyltinosposide A (12) exhibited mild cytotoxicity against HeLa cells, with an IC50 value of 8.35 ± 0.60 µM.

[Studies on chemical constituents of Clerodendrum bungei].

Ten compounds were isolated from the 95% aqueous EtOH extract of Clerodendrum bungei by a combination of various chromatographic techniques including column chromatography over silica gel, Sephadex LH-20, MCI, ODS, and semi-preparative HPLC. Their structures were elucidated as 11,12,16S-trihydroxy-7-oxo-17(15→16),18(4→3)-diabeo-abieta-3,8,11,13-tetraen-18-oic acid (1), 12S*,13R*-dihydroxy-9-oxo-octadeca-10(E)-enoic acid (2), clerodenoside A (3), trichotomoside (4), glycosmisic acid (5), 4'-O-methylscutellarein (6), neroplomacrol (7), butylitaconic acid (8), hexylitaconic acid (9), p-hydroxybenzonic acid (10) by their physicochemical properties and spectroscopic data. Compounds 1 and 2 are new natural products, while compounds 7-10 were obtained from the genus Clerodendrum for the first time, and compounds 3, 5, 6 were isolated from this plant for the first time.

Cytisine-type alkaloids and flavonoids from the rhizomes of Sophora tonkinensis.

A new cytisine-type alkaloid, (-)-N-hexanoylcytisine (1), and a new isoflavan, (3S, 4R)-4-hydroxy-7,4'-dimethoxyisoflavan 3'-O-ß-d-glucopyranoside (2), along with 10 known compounds, were isolated from the rhizomes of Sophora tonkinensis. Their structures were determined by spectroscopic methods, chemical evidence, and ECD data analysis. All of the isolates were evaluated for their cytotoxic activities against four human tumor cell lines.

[A new indole alkaloid from the stems of Brucea mollis].

Eight compounds were isolated from the stems of Brucea mollis by various chromatographic techniques such as column chromatography on silica gel and Sephadex LH-20, and preparative HPLC, and their structures were elucidated as bruceolline O (1), 1-(1-beta-glucopyranosyl)-1H-indole-3-carbaldehyde (2), canthin-6-one (3), 11-hydroxycanthin-6-one (4), 9-methoxycanthin-6-one (5), 4-methoxycanthin-6-one (6), infractin (7), and beta-carboline-1-propionic acid (8). The cytotoxic activities of compounds 1-8 against HCT-8 and A549 human cell lines were determined, but none of them exhibited significant activity (IC 50 > 10 micromol x L(-1)). Among them, compound 1 is a new indole alkaloid, and compounds 2 and 5-7 were isolated from this plant for the first time.

Diterpenoids and sesquiterpenoids from the roots of Illicium majus.

Five new diterpenoids (1-5), five new sesquiterpenoids (6-10), and three known compounds (11-13) were isolated from the roots of Illicium majus. Their structures were elucidated by extensive spectroscopic analysis. The absolute configuration of 1 was assigned by X-ray crystallography, whereas those of the 1,2-diol moieties in 3 and 4 were determined using Snatzke's method. The abietane acids 1, 2, 11, 12, and 13 displayed antiviral activity against the Coxsackie B3 virus, with IC50 values of 3.3-51.7 µM/mL.

Novel sesquiterpenoid glycosides and sesquiterpenes from the roots of Illicium henryi.

Seven new sesquiterpenoid glycosides, consisting of one thapsan-type (1), two capnellane-type (2 and 3), four floridanolide sesquiterpene glycosides (4-7), and one new azulene-type sesquiterpene (8), along with six known sesquiterpenes (9-14) were isolated from the roots of Illicium henryi. The structures of 1-8 were elucidated by extensive spectroscopic analyses and chemical methods. The absolute configurations of 1, 2, and 8 were determined based on Rh2(OCOCF3)4-induced CD, Mo2(OAc)4-induced CD data, and calculated electronic circular dichroism (ECD), respectively. Compound 1 was found to exhibit weak neurotoxicant activity.

Diterpenoids and sesquiterpenoids from the twigs and leaves of Illicium majus.

Four new abietane diterpenes (1-4) and two new cycloparvifloralone-type sesquiterpenoids (5-6) have been isolated from the twigs and leaves of Illicium majus, together with three known sesquiterpenoids and five known diterpenoids. Their structures were determined by spectroscopic analysis and chemical methods. The absolute configuration of the 15,16-diol moiety in 2 is confirmed by Snatzke's method, observing the induced circular dichroism after the addition of dimolybdenum tetraacetate in DMSO. Compound 2 exihibited significant anti-inflammatory activity with an IC50 value of 0.26 ± 0.03 µM, while compounds 10, 11, and 13 showed good anti-inflammatory activities with IC50 values ranging from 1.94 ± 0.56 to 2.60 ± 0.48 µM.

Cytotoxic triterpenoid saponins from Lysimachia clethroides.

Seven oleanane-type triterpenoid saponins, named clethroidosides A-G (1-7), an ursane-type triterpenoid saponin, clethroidoside H (8), and six known saponins were isolated from the aerial parts of Lysimachia clethroides. The structures of the saponins were elucidated on the basis of physical data analysis (1D and 2D NMR, HR-ESIMS) and chemical evidence. The cytotoxic activities of compounds 1-14 were evaluated against five human tumor cell lines (HT-29, HePG2, BGC-823, A549, and A375). Compounds 3, 4, 6, and 11-13 exhibited moderate cytotoxic activity, with IC50 values of 0.75-2.62 µM, while compound 5 showed selective cytotoxic activity.