Three new pterosins from Pteris semipinnata.

Three new pterosins, named as semipterosin A (1), B (2) and C (3), together with 11 known pterosins (4-14), were isolated from the aerial parts of Pteris semipinnata. Their structures were elucidated by HRESI-MS, NMR spectral data, CD and literature comparisons. Three new pterosins were assessed for their anti-inflammatory activity. Compounds 1-3 inhibited the NF-kB induction by 40.7%, 61.9% and 34.0%, respectively. This is the first report of the isolation of compounds 6-14 from this plant.

Three new flavonoid glycosides isolated from Pteridium aquilinum.

Three new flavonoid glycosides, (S)-4',6,8-trihydroxyflavanone-7-C-glucoside (1), (R)-4',6,8- trihydroxyflavanone-7-C-glucoside (2) and distenin-7-O-ß-D-glucoside (3), along with nine known flavonoids (4-12) were isolated from the aerial of Pteridium acquilinum. Their structures were elucidated by the analysis of spectroscopy data and their comparison with the reported values. The two C-glycosyl flavanones (1 and 2), were isolated from this specie, which might be chemotaxonomic markers of this specie. In addition, three new flavonoids were preliminarily examined for their anti-inflammatory activity. Compounds 1-3 inhibited the NF-κB induction by 46.3%, 59.6% and 29.2%, respectively.

Three novel pterosin dimers form Pteris obtusiloba.

Three novel pterosin dimmers, named as obtupterosin A (1), B (2) and C (3), together with eight known pterosins (4-11) were isolated from Pteris obtusiloba. Their structures were elucidated on the basis of ESI-MS, 1D and 2D NMR spectral data, CD, X-ray and literature comparisons. Compounds 1 and 2 were a pair of isomers. Compounds 1 and 3 were the novel type of pterosin dimer. The new compounds (1-3) were assessed for their cytotoxic activities and their α-glucosidase inhibition activity. Compounds 1-3 exhibited cytotoxic activity against HCT-116 cells with IC50 value of 27.5 µM, 30.6 µM and 12.8 µM, respectively. However, all were found to be inactive at 200 µM for α-glucosidase inhibition.

A new triterpenoid and a new flavonoid glycoside isolated from Bupleurum marginatum and their anti-inflammatory activity.

This study to investigate chemical constituents from the aerial of Bupleurum marginatum led to the isolation of a new trierpenoid and a new flavonoid, namely 3ß-hydroxy-cycloart-24-en-26-acetyloxy (1), and 3, 3', 5'-trimethoxyl-myricetin 7-O-ß-D-glucopyranoside (2) along with eight known compounds (3-10). Their structures were established by spectral data analyses (MS, 1D and 2D NMR), as well as by comparison of spectral data with those of the related known compounds. The 24-en-lanostane type triterpenoid with a cyclopropane ring (1 and 3) was firstly reported from this specie, which might be chemotaxonomic markers of this specie. In addition, compounds 1 and 2 were examined for their anti-inflammatory activity. Compounds 1 and 2 inhibited the NF κB induction by 60.61% and 24.30%.

Four New Pterosins from Pteris cretica and Their Cytotoxic Activities.

Phytochemical investigation of the aerial parts of Pteris cretica led to the isolation and elucidation of nine pterosins, including four new pterosins, creticolacton A (1), 13-hydroxy-2(R),3(R)-pterosin L (2), creticoside A (3), and spelosin 3-O-ß-d-glucopyranoside (4), together with five known pterosins 5-9. Their structures were identified mainly on the basis of 1D and 2D NMR spectral data, ESI-MS and literature comparisons. Compounds 1 and 3 were new type of petrosins with a six membered ring between C-14 and C-15. The new compounds were tested in vitro for their cytotoxic activities against four human tumor cell lines (SH-SY5Y, SGC-7901, HCT-116, Lovo). Results showed that compounds 1 and 2 exhibited cytotoxic activity against HCT-116 cells with IC50 value of 22.4 µM and 15.8 µM, respectively.

Three new flavonoid glycosides from Smilax glabra and their anti-inflammatory activity.

Three new flavonoid glycosides, 2(S)-5-hydroxy-6,8-dimethoxyflavonone-7-O-ß-D-glucopyranosyl-(1→6)-O-ß-D-glucopyranoside (1), 5-hydroxy-3,8-dimethoxyflavone-7-O-ß-D-glucopyranosyl-(1→6)-O-ß-D-glucopyranoside (2) and 3,7-dihydroxy-8-methoxyflavone-6-O-ß-D-glucopyranosyl-(1→6)-O-ß-D-glucopyranoside (3), together with five known flavonoids (4-8) were isolated from the roots of Smilax glabra Roxb. Their structures were elucidated on the basis of chemical and spectral evidence, as well as by comparison with literature data. Three new flavonoids were subjected to evaluate anti-inflammatory activity. Compounds 1-3 inhibited the NF κB induction by 32.2, 55.8 and 61.7%, respectively.

Diterpenoids from Leaves of Rubus chingii.

The leaves of Rubus chingii were examined for their phytochemical composition and anti-yeast activity. In the process, seven diterpenoids (compounds 1-7), including a new natural compound (14ß, 16-epoxy-7-pimarene-3α, 15ß-diol, 1), were isolated and elucidated. Compound 1 exhibited moderate anti-Candida activity.

[Flavonoids from leaves of Psidum littorale].

We investigated the chemical constituents of the leaves of Psidum littorale, which include 16 flavonoids, including seven flavonols, six flavonoid glycosides and three flavonones. The compounds were isolated by silica gel column chromatography. Their structures were elucidated on the basis of spectral analysis and by comparison with published data. Seven flavonols were kaempferol (1), isorhamnetin (2), myricetin- 3,7,3'-trimethyl ether(3), laricitrin (4), quercetin (5), myricetin (6) and quercein-3,4'-dimethyl ether (7), six flavonoid glycosides were guaijaverin (8), hyperoside (9), 5,4'-dyhydroxy-3,7,5'-methoxyflavone-3'-O-ß-D- glucoside (10), laricitrin-3-O-xyloside (11), myricetin-3-O-α-L-rhamnopyranoside (12) and myricetin-3-O-ß-D- xyloside (13). Three flavonones were 4'-O-methyldihydroquercetin (14), dihydroapigenin (15) and ampelopsin 4'-O-ß-D-glucopyranoside (16). Compound 10 is a new chemical, compounds 2-4, 7, 10-16 were first isolated from this plant. (1)H NMR and (13)C NMR data of compound 11 were not reported in literature.

A new alkaloid from the fruit of Nandina domestica Thunb.

A new steroidal alkaloid, (20S,22R,24R)-24-ethyl-3-oxocholest-4-en-22-amino, named as nandsterine (1), together with 10 known alkaloids, palmatine (2), O-methylbulbocapnine (3), nantenine (4), dehydronantenine (5), glaucine (6), didehydroglaucine (7), dehydrocorydaline (8), jatrorrhizine (9), magnoflorine (10) and berberine (11), was isolated from the fruit of Nandina domestica Thunb. Their structures were elucidated by using spectroscopic methods as well as by comparing with the published data. Compound 1 was a new class of steroidal alkaloid isolated from the family Berberidaceae, meanwhile compounds 2, 3, 6-8 and 10 were obtained from N. domestica for the first time. Compound 1 exhibited cytotoxicity against HL-60 cells (human leukaemia) with IC50 values of 52.1 µM.

[Study on Megastigmane Glycosides and Lignan Constituents from Leaves of Psidium littorale].

OBJECTIVE: To study the chemical constituents of the leaves of Psidium littorale. METHODS: The constituents were isolated with silica gel column chromatography and the structures of these compounds were elucidated on the basis of spectral analysis. RESULTS: Four megastigmane glycosides and three lignans were isolated and their structures were identified as Bridelionoside B(1), Euodinoside E(2), (3S,5R,6R,7E,9S)-Megastignan-7-ene-3,5,6,9-tetrol 9-O-ß-D-glucopyranoside (3), Bridelionoside C(4), (--)-Isolaricires-inol 3-α-O-ß-D-glucopyranoside (5), (--)-5'-methoxy-Isolariciresinol 3-α-O-ß-D-glucopyranoside (6) and dihydrodehydrodiconiferyl alcohol 4-O-ß-D-glucopyranoside(7). CONCLUSION: Compounds 1-7 are isolated from this plant for the first time. The results have provided the scientific basis for further exploitation of Psidium littoratle.