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Two new acylated flavone C-glycosides, 6''-O-(2'''-methylbutyryl)isoswertisin (1) and 6''-O-(2'''-methylbutyryl)isoswertiajaponin (2), together with four known acylated flavone C-glycosides, were isolated for the first time from the whole plants of Hemistepta lyrata (Compositae). Their structures were elucidated on the basis of chemical and spectroscopic methods including HR-ESI-MS, ESI-MS, UV, IR, and 1D and 2D NMR spectral techniques.

Two new glycosides, 1,6-di-O-syringoyl-β-d-glucopyranose (1) and quercetin 3-O-[(3-O-syringoyl-α-l-rhamnopyranosyl)-(1 → 6)-β-d-glucopyranoside] (2), along with seven known compounds were isolated from the MeOH extract of Leonurus japonicus. The structures of these compounds were elucidated by spectral analysis.

In this paper, a simple and novel synthesis of baicalein is described. This transformation features the novel synthesis of helilandin B and a different way to demethylate. The overall yield of 59% is acceptable.

A novel C-glycosylflavone with unusual alpha-orientation at the anomeric center of d-glucose was isolated from the leaves of Diospyros kaki. Its structure was determined as 8-C-[alpha-l-rhamnopyranosyl-(1 --4)]-alpha-d-glucopyranosylapigenin by chemical methods and spectral experiments.

A new acylated flavone glycoside, echioidinin 2'-O-beta-D-(2''-O-acetyl)glucopyranoside (1) along with the three known flavonoids, 5,6,7,8,5'-pentamethoxy-3',4'-methylenedioxyflavone (2), 5,2',6'-trihydroxy-7-methoxyflavone (3), and kaempferol 7,4'-dimethyl ether 3-O-beta-D-glucopyranoside (4), were isolated from the roots of Colebrookea oppositifolia. The structure of compound 1 was elucidated by extensive spectral and chemical studies.

Two new steroidal saponins and two known flavonoid glycosides were isolated from the fruits of Tribulus terrestris. Their structures were assigned by spectroscopic analysis and chemical reaction as 26-O-beta-D-glucopyranosyl-(25R)-5 alpha-furostan-12-one-3beta,22 alpha,26-triol-3-O-beta-D-glucopyranosyl (1 --2)-beta-D-glucopyranosyl(1 --4)-beta-D-galactopyranoside (1), 26-O-beta-D-glucopyranosyl-(25S)-5 alpha-furostan-22-methoxy-2 alpha,3beta,26-triol-3-O-beta-D-glucopyranosyl(1 --2)-beta-D-glucopyranosyl(1 --4)-beta-D-galactopyranoside (2), kaempferol-3-gentiobioside (3), and isorhamnetin-3-gentiobioside (4).

Two new flavonoids, compounds 1 and 2, together with seven known flavonoids, were isolated from Galium verum L. Their structures were elucidated as diosmetin 7-O-alpha-l-rhamnopyranosyl-(1-2)-[beta-d-xylopyranosyl-(1-6)]-beta-d-glucopyranoside (1) and 3,5,7,3',4',3'',5'',7'',3''',4'''-decahydroxyl-[8-CH(2)-8'']-biflavone (2) by chemical methods and spectroscopic analyses. Compounds 3 and 4 were isolated from the genus Galium for the first time.

A novel flavonoid, [2-(3,4-dihydroxy-phenyl)-3,5,7-trihydroxy-4-oxo-4H-chromen-8-yl]-[8-hydroxy-7-(E-4-hydroxy-3-methyl-but-2-enyl)-2,2-dimethyl-chroman-5-yl]-acetic acid methyl ester (10), trivially named sabian, along with 11 known compounds, have been isolated from the stems and leaves of Sabiayunnanensis. Their structures were established on the basis of spectral analysis.

Two new flavonosides have been isolated from the roots of Glychirriza glabra and identified as 5,8-dihydroxy-flavone-7-O-beta-D-glucuronide, glychionide A, and 5-hydroxy-8-methoxyl-flavone-7-O-beta-D-glucuronide, glychionide B.

Scutellarin-7-O-glucuronide (1) has been synthesized from 2-hydroxyl-4,5,6-trimethoxyacetophenone through eight steps, including Michael addition, cyclization, hydrogenation, hydroxyl protection, deprotection, etc. The overall yield of 13% is much higher than that reported (0.6%) by L. Farkas, G. Mezey-Vàndor et al. in 1974.

In a chemical investigation on the flavone composition of Leonurus heterophyllus a new flavonoside has been isolated. By means of physico-chemical evidences and spectral analysis its structure has been established as quercetin-3-O-[3-(4-hydroxy-3,5-dimethoxybenzyl)-alpha-L-rhamnopyranosyl]-(1--6)-beta-D-galactopyranoside (1).

A new flavonoid was isolated from the whole plant of Spiranthes australis (R. Brown) Lindl (Orchidacea). Its structure was characterized as 3,7-dimethoxy-5-hydroxy-2-([4-(3-methyl-2-butenyl)oxy]phenyl)-4H-1-benzopyran-4-one on the basis of chemical and spectral evidence including 2D NMR analysis.

Thalictrum (Ranunculaceae) is an extremely abundant medicinal plant source. Due to their marked ethnopharmacological usages in folk medicine of China and the large number of potentially active chemical constituents, they may be a rich source for new chemicals for drug R&D. Here, an investigation on traditional functions and folk therapeutic uses of Thalictrum plants from China, as well as their main chemical constituents, was undertaken. It showed that 43 Thalictrum plants have long been used as folk medicine to treat many diseases in different races of China. In addition, the correlation between folk therapeutic effects and chemical constituents, and the modern pharmacological activities, are discussed as well as the prospect of isolation and development of new drugs from this genus of plants.

Three new flavonol triglycosides, kaempferol-3-O-alpha-L-rhamnopyranosyl-(1 -> 6)-beta-D-glucopyranosyl-(1 -> 3)-beta-D-glucopyranoside (1), quercetin-3-O-alpha-L-rhamnopyranosyl-(1 -> 6)-beta-D-glucopyranosyl-(1 -> 3)-beta-D-glucopyranoside (2), quercetin-3-O-alpha-L-rhamnopyranosyl-(1 -> 6)-beta-D-glucopyranosyl-(1 -> 2)-beta-D-glucopyranoside (3), together with the two known flavonol glycosides, kaempferol-3-O-alpha-L-rhamnopyranosyl-(1 -> 6)-beta-D-glucopyranoside and kaempferol-3-O-alpha-L-rhamnopyranosyl-(1 -> 6)-beta-D-glucopyranosyl-(1 -> 2)-beta-D-glucopyranoside, were isolated from the aerial parts of Derris trifoliata. Their structures were determined on the basis of chemical and spectroscopic analyses.

Two new compounds, alternanthin B (1) and N-trans-feruloyl-3,5-dimethoxytyramine (2), along with four known compounds (3-6) were isolated from the aerial parts of Alternanthera philoxeroides. Their structures were elucidated on the basis of spectroscopic methods. The antitumor activity of the isolated compounds was also evaluated.

Three new C-glycosylflavones, named 5,7,4'-trihydroxy-6-methoxy-8-C-[beta-D-xylopyranosyl- (1 --2)]-beta-D-glucopyranosyl flavonoside (1), 5,7,4'-trihydroxy-8-methoxy-6-C-[beta-D-xylopyranosyl-(1 --2)]-beta-D-glucopyranosyl flavonoside (2), and 5,3',4'-trihydroxy-7,8-dimethoxy-6-C-[beta-D-xylopyranosyl-(1 --2)]-beta-D-glucopyranosyl flavonoside (3), along with two known compounds 5,4'-dihydroxy-7-methoxy-6-C-glucopyranosyl-flavonoside (4), 3-methoxy-4-hydroxymethyl benzoate (5) were isolated from 70% acetone extract of Corallodiscus flabellata. Their structures were identified on the basis of spectroscopic techniques and chemical methods.

A new kaempferol glycoside, kaempferol-3-O-beta-D-glucopyranoside-7-O-alpha-L-arabinofuranoside (1), was isolated from the EtOH extract of Pyrrosiapetiolosa together with six known flavonoids already reported from the same plant. Structural elucidation was performed by means of physico-chemical methods including MS, and 1D and 2D NMR spectroscopy.

A new chromone named as 5,4′-dihydroxy-7-methyl 3-benzyl chromone (1) along with three known flavonoid compounds as unsubstituted flavone, kaempferol-3-o-rhamnoside and quercetin-3-o-arabinoside have been isolated from the leaves of Cassia nodosa. Their structures have been established by means of chemical and spectral evidences (IR, UV, 1H-NMR, 13C-NMR and mass spectra).

A new meta-homoisoflavane, 10,11-dihydroxydracaenone C (1), together with 7,4 '-dihydroxyflavone (2), 7,4 '-dihydroxyflavane (3), 4,4 '-dihydroxy-2-methoxychalcone (4), 4,4 '-dihydroxy-2-methoxydihydrochalcone (5), 7,4 '-dihydrohomoisoflavanone (6), 7,4 '-homoisoflavane (7), lophenol (8), beta-sitosterol (9), stigma-5, 22-diene-3-ol ( 10), 1-(4 '-O-beta-D-glucopyranosyl) benzyl-ethan-2-ol (11), 3,4-dihydoxy-1-allylbenezene-4-O-alpha-L-rhamnopyranosyl-(1 -> 6)-O-beta-D-glucopyranoside (12), 1-hydroxy-3,4,5-trimethoxybenzene1-O-alpha-L-apiopyranosyl-(1 -> 6)-O-beta-D-glucopyranoside (13), and tachioside (14) have been isolated from the fresh stems of Dracaena cochinchinensis. Their structures have been established by spectroscopic analysis, especially by 2D NMR. This is the first time compounds 11, 13, 14 have been isolated from Dracaena.

Melilotus indica All. [Chopra, R.N., Nayar, S.L. and Chopra, I.C. (1956) Glossary Indian Med. Plants, 164 C.S.I.R. Publication New-Delhi; Kirtikar, K.R. and Basu, B.D. (1935) Indian Medicinal Plants, 2nd Ed., Vol. I, pp. 703-704 Lalit Mohan Basuan Co. Allahabad. The Wealth of India (1962) A Dictionary of Raw Materials and Industrial Products, Vol. VI, pp. 329-331 (C.S.I.R. Publication: New-Delhi)] belongs to family Leguminosae, which is commonly known as 'Banmethi' in Hindi. It is found in North India, extending into S. Persia, S. Europe and the Tropical zone of India. The seeds are used as an anthelmintic, an antipyretic, for curing heart diseases, bronchitis, leprosy, bowel complaints and infantile diarrhea. The plant has also been used as a discutient, emollient, and as a fomentation. It is also useful in a plaster for swelling. It is considered astringent and narcotic. Earlier workers have reported the presence of C-glycosides [Sayed, E.L., Ishak, M.S. and Mabry, T.J. (1997) Asian J. Chem., 9, 551], methylene-dioxypterocarpan (MIS6) [Saxena, V.K. and Nigam, S. (1997) Fitoterapia, 68, 343-345], pterocarpane (MIS2) [Saxena, V.K. and Nigam, S. (1996) J. Institution Chem. 68, 122-125] and prenylated pterocarpan [Saxena, V.K. and Nigam, S. (1997) Fitoterapia, 68, 403-407] from this plant. Here, we report the isolation of the new flavone glycoside 5,7,4'-trihydroxy-6,3'-dimethoxyflavone-7-O-alpha-L-arabinopyranosyl(1--6)-O-beta-D-galactopyranoside (1) from the seeds of this plant.

Two new flavonoids, named sphaerophyside SA and sphaerophyside SB, together with 15 known flavonoids were isolated from the ethanolic extract of the seeds of Sphaerophysa salsula (Pall.) DC. The structures of the new compounds were elucidated mainly on the basis of the 1D and 2D NMR data.

The new flavone diglycoside 7-O-[6-O-(alpha-L-arabifuranosyl)-beta-D-glucopyranosyl]-gossypetin, named as pyrropetioside, along with 13 known compounds (including 3 artifacts) have been isolated from Pyrrosia petiolosa. Their structures have been elucidated by means of chemical and spectroscopic methods including IR, MS, 1D and 2D NMR techniques.