Chemical investigations of aerial parts of Tephrosia purpurea yielded the rare prenylated flavonoids, tephropurpulin A (1) and isoglabratephrin (2), in addition to a previously identified flavonoid, glabratephrin (3). Structures were established by 1D and 2D NMR spectroscopy, as well as by HR-MS analysis; for compounds 2 and 3, structures were confirmed by X-ray analysis.

A new flavonoid, 5,7,3'-trihydroxy-6-C-beta-D-digitoxopyranosyl-4'-O-beta-D-glucopyranosyl flavonoside (1), along with four known flavonoids 5,7,4'-trihydroxy-3',5'-dimethoxy flavone (2), 5,3',4'-trihydroxy-7-O-beta-D-glucopyranosyl flavonoside (3), 5,4'-dihydroxy-3',5'-dimethoxy-7-O-beta-D-glucopyranosyl flavonoside (4), 5,3',4'-trihydroxy-6-C-[beta-D-glucopyranosyl-(1 --> 6)]-beta-D-glucopyra...

Two lactoylate flavonoids, luteolin-7-lactate and luteolin-7-glucosyl-lactate were isolated from Ballota nigra. They should be used for the chemical standardization of this drug of medicinal interest.

The infusion of the aerial parts of Turnera diffusa was phytochemically examined. Chromatographic procedures led to the isolation of a new flavone glycoside, five known flavonoids and p-arbutin. Structures were determined by 1D- and 2D NMR experiments, as well as ES-MS and UV spectra.

T he m ajo r constituent of the yellow frond exudate of the fern Notholaena sulphurea was iden tified by spectroscopic m ethods as 3 ,5 ,2 '-trihydroxy-7-m ethoxy-8-acetoxy flavone and its struc tu re was confirm ed by synthesis. This novel natural flavonoid was also de tected in the frond exudate of five o ther Notholaena species. In the yellow form of N. sulphurea, the rare 5 ,2 'dihydroxy-7,...

Flavonoids are a family of antioxidants found in fruits and vegetables as well as in popular beverages such as red wine and tea. Although the physiological benefits of flavonoids have been largely attributed to their antioxidant properties in plasma, flavonoids may also protect cells from various insults. Nerve cell death from oxidative stress has been implicated in a variety of pathologies, in...

Two new flavonoids, 5, 7, 2', 5'-tetramethoxyflavanone (1) and 5-hydroxy-7, 2'-dimethoxyflavone (2), together with two known flavones, skullcapflavone I (3) and echioidin (4) were isolated from the whole plant of Andrographis rothii. The structures of the new compounds were established by extensive one- and two-dimensional (1D- and 2D-) NMR spectral studies.

In a bioassay-guided search for acetylcholinesterase (AChE) inhibitors from 180 medicinal plants, an ethyl acetate extract of whole plants of Agrimonia pilosa ledeb yielded tiliroside (1), 3-methoxy quercetin (2), quercitrin (3) and quercetin (4). We report herein for the first time that all four flavonol compounds showed significant inhibitory effects on AChE, particularly quercetin (4), which...

Phytochemical studies on the ethanolic extract of the aerial parts of Centaurea scoparia led to the isolation of two new flavonoids, 3',4'-dihydroxy-(3'',4''-dihydro-3''-hydroxy-4''-acetoxy)-2'',2''-dimethylpyrano-(5'',6'':7,8)-flavone-3-O- β -D-glucopyranoside (1) and 3,3',4'-trihydroxy-(3'',4''-dihydro-3'',4''-dihydroxy)-2'',2''-dimethylpyrano-(5'',6'':7,8)-flavone (2), along with eight known...

Flavonoids tricin, iso-orientin, vanillin, iso-vitexin, apigenin, 8-hydroxy flavones, 4’-hydroxy chalcone have been isolated from leaves of early stage triticum aestivum. Their quantitative analysis has been done through elemental and spectral analysis.