Neolignan and phenylpropanoid compounds from the resin of Styrax tonkinensis.

A new neolignan compound, tonkinensisin A (1), and two phenylpropanoid compounds, tonkinensisin B (2) and tonkinensisin C (3), were isolated from the resin of Styrax tonkinensis (Pierre) Craib ex Hartw. The structures of these compounds were determined by spectroscopic analysis, and the relative configurations of compounds 1 and 3 were determined by J-based configuration analysis (JBCA) method. All compounds were assayed for cytotoxic activities against five tumor cell lines (HepG-2, A549, Hela, MCF-7, and PC-3) by CCK-8 test in vitro.[Formula: see text].

Cysestermerol A, a rare stilbene sestermer with significant hypoglycemic activities from Cynodon dactylon.

Cysestermerol A (1), a rare and new stilbene sestermer, was isolated from the whole herb of Cynodon dactylon. The planar and relative structures of 1 were elucidated based on HRESIMS, one- and two-dimensional NMR analyses, and its absolute configuration was further established by electronic circular dichroism calculations. Compound 1 obviously increased the glucose consumption in HepG2 cells equivalent to the positive control rosiglitazone and markedly inhibited the activity of α-glucosidase in vitro.

Novel sesquilignan and lignan glycoside from the twigs and leaves of Illicium majus.

A novel sesquilignan compound (1), possesing an unusual carbon skeleton of aryltetralin unit linked with a C6-C3 unit and a five-membered ring by a C-7″ and C-4 linkage pattern via an oxygen atom, and a new lignan glycoside (2) have been isolated from the twigs and leaves of Illicium majus. Their structures were determined by spectroscopic analysis and chemical methods. The absolute configurations of 1 and 2 are confirmed by observing the circular dichroism. At 10 µM, Compounds 1 and 2 showed in Vitro inhibitory activity against the release of ß-glucuronidase in rat polymorphonuclear leukocytes induced by platelet-activating factor.

[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.

[Chemical constituents from stems of Brucea mollis and their cytotoxic activity].

Ten 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 deacetylated isobrucein B (1), indaquassin X (2), cleomiscosin A (3), cleomiscosin B (4), (+)-lyoniresinol (5), (+)-epipinoresinol(6), (+)-pinoresinol (7), (+)-syringaresinol (8), 4,5-dihydroblumenol A (9) and adenosine (10) on the basis of spectroscopic data analysiS. All compounds were obtained from this plant for the first time, moreover, compound 1 was a new natural product. Compound 2 showed significant cytotoxic activities against the human cell lines HT-29, HepG2, BGC-823 and SKOV3 with IC50 values of 0.84-3.97 micromol x L(-1).

Tirucallane triterpenoids from the stems of Brucea mollis.

Three new tirucallane triterpenoids, brumollisols A-C (1-3, resp.), together with five known analogues, (23R,24S)-23,24,25-trihydroxytirucall-7-ene-3,6-dione (4), piscidinol A (5), 24-epipiscidinol A (6), 21α-methylmelianodiol (7), and 21ß-methylmelianodiol (8), were isolated from an EtOH extract of the stems of Brucea mollis. Their structures were elucidated by means of spectroscopic methods including 1D- and 2D-NMR techniques and mass spectrometry. In the in vitro assays, compound 6 exhibited significant cytotoxic activity against A549 and BGC-823 cancer cells with IC50 values of 1.16 and 3.01 µM, respectively. At a concentration of 10 µM, compounds 1-5, 7, and 8 were found to inhibit NO production in mouse peritoneal macrophages with inhibitory ratios ranging from 39.8±7.7 to 68.2±4.5%.

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.

Sesquiterpenes and neolignans from the roots of Illicium dunnianum.

Two new sesquiterpenes, dunnianoside I (1) and 8'-oxo-6-hydroxy-dihydrophaseic acid methyl ester (2), a new glycoside, dunnianoside J (3), two new neolignans, dunnianeolignans A-B (4, 5), together with 10 known compounds (6-15), were isolated from the roots of Illicium dunnianum. The structures of these new compounds were elucidated by spectroscopic methods including 1D and 2D NMR, HR-ESI-MS, and chemical methods. Compounds 7, 8, and 13-15 exhibited potent antioxidant activities against Fe²âº-cystine-induced rat liver microsomal lipid peroxidation, with IC50 values ranging from 4.2 ± 0.4 to 38.4 ± 2.6 µM.

Antioxidant phenolic glycosides from the roots of Illicium dunnianum.

Eight new phenolic glycosides, dunnianosides A-H (1-8), and nine known phenolic glycosides (9-17), were isolated from the roots of Illicium dunnianum. The structures of these new compounds were elucidated by spectroscopic methods including 1D and 2D NMR, HRESIMS, and chemical methods. Compounds 1-5, 7, and 9 exhibited potent antioxidant activities against Fe(2+)-cystine-induced rat liver microsomal lipid peroxidation, with IC(50) values ranging from 3.8 ± 0.6 to 23.0 ± 2.2 µM.

Sesquiterpenes from the roots of Illicium dunnianum.

Six allo-cedrane sesquiterpenes, four seco-prezizaane-type sesquiterpenes, two monocyclofarnesane sesquiterpenes, together with four known sesquiterpenes, were isolated from the roots of Illicium dunnianum. The structures were elucidated by spectroscopic methods including 1D and 2D NMR. The absolute configuration of 10 was determined by a CD experiment. Compounds 11 and 13 showed potent activities against the release of ß-glucuronidase in rat polymorphonuclear leukocytes induced by platelet-activating factor in vitro, with IC50 values of 2.10±0.40 and 1.93±0.57 µM, respectively. All compounds were evaluated for cytotoxicities against five human cancer cell lines (A549, Bel-7402, BGC-823, HCT-8, and A2780) in the MTT assay, but none of them exhibited activity at concentrations tested (10⁻5-10⁻7 M).

Bioactive quassinoids from the seeds of Brucea javanica.

Six new quassinoids (1-6) and eight known compounds of this type (7-14) were isolated from the seeds of Brucea javanica. Their structures were elucidated by analysis of their spectroscopic data and from chemical evidence. Compounds 1-5 were found to be unusual quassinoids with a 2,3-seco A ring. The configurations at C-4 in 4 and 5 were determined by a difference circular dichroism method. In in vitro bioassays, 8 and 10 showed inhibitory activities for nitric oxide production in LPS-activated macrophages, with IC(50) values of 1.9 and 5.0 µM, respectively, while compounds 6, 8-11, 13, and 14 exhibited cytotoxicity against five human tumor cell lines (HCT-8, HepG2, BGC-823, A549, and SKVO3), having IC(50) values in the range 0.12-9.3 µM.

Indole alkaloids and quassinoids from the stems of Brucea mollis.

Seven new indole alkaloids, bruceollines H-N (1-7), three new quassinoids, yadanziolides T-V (10-12), and four known analogues, bruceolline E (8), bruceolline F (9), bruceine D (13), and yadanziolide B (14), were isolated from an ethanol extract of the stems of Brucea mollis. The absolute configurations of compounds 2 and 5 were determined by comparison of their experimental and calculated ECD spectra. The absolute configuration of the known compound 9 was determined by using Mo2(OAc)4-induced CD analysis for the first time. Compounds 10, 13, and 14 exhibited cytotoxic activities with IC50 values of 3.00-5.81 µM.

[Studies on chemical constituents from Euonymus alatus II].

OBJECTIVE: To study the chemical constituents and antitumor activities of Euonymus alatus. METHOD: Compounds were isolated and purified repeatedly by silica gel, Sephadex LH-20 column chromatography, and their chemical structures were elucidated by their physicochemical properties and spectral data, such as 1H-NMR, 13C-NMR and EI-MS. The trypan blue experiments in vitro were used to observe the antitumor activity of several compounds. RESULT: Ten compounds were obtained and identified as (+)-usnic acid (1), benzoic acid (2), 2-hydroxy-4-methoxy-3, 6-dimethyl benzoic acid (3), lupeol (4), 3 beta-hydroxy-30-norlupan-20-one (5), (2R, 3R)-3, 5, 7, 4'-tetrahydroxy flavanone (6), kaempferol (7), 5, 7, 4'-trihydroxy flavanone (8), quercetin (9) and daucosterol (10). CONCLUSION: Compounds 1, 2, 5 and 8 were isolated from this genus for the first time. The trypan blue experiments in vitro showed that compounds 1, 4 and 5 had growth inhibitory effects on HL-60 cells.