Myricetin and quercetin methyl ethers from Haplopappus integerrimus var. Punctatus

Nine flavonoids including two new myricetin derivatives, myricetin 3′,4′-dimethyl ether and myricetin 3,3′, 4′-trimethyl ether, were obtained from Haplopappus integerrimus var. punctatus. The known compounds are quercetin 7,3′-dimethyl ether, querectin 3,3′-dimethyl ether, isorhamnetin, quercetin 3,7-dimethyl ether, quercetin 3-methyl ether, quercetin and quercetin 3-β-d-glucoside.     

6-Methoxyflavonols from Brickellia veronicaefolia (compositae)

Three new and eight known flavonols, all containing 6-methoxyl groups, were isolated from Brickellia veronicaefolia. The new compounds were eupatolitin 3-sulfate, 6-methoxyquercetin 7,3′-dimethyl ether (veronicafolin) 3-digalactoside and veronicafolin 3-sulfate. The known flavonoids were eupatolitin, quer-cetagetin 3,6,7-trimethyl ether, eupatin, casticin, artemetin, eupatolitin 3-galactoside, patuletin 3-sulfate and eupatin 3-sulfate.     

Flavones from Eupatorium leucolepis

Chloroform extraction of Eupatorium leucolepis gave the new flavones 3′-hydroxy-5,6,7,8,4′,5′-hexamethoxyflavone, 4′-hydroxy-5,6,7,8,3′,5     

Flavonoids from Artemisia frigida

Twelve flavonoids including a new flavone were isolated from Artemisia frigida. The structure of the new highly oxygenated flavone was determined b     

Flavonoids from Brickellia chlorolepis and B. dentata

Eleven flavonoids including three new glycosides were isolated from Brickellia chlorolepis and one new and nine known flavonoids were obtained from B. dentata. The new glycosides from B. chlorolepis are 6-methoxykaempferol 3-rhamnoglucoside, spinacetin 3-rhamnogalactoside and veronicafolin 3-rhamnoglucoside. The known compounds identified from B. chlorolepis are patuletin, casticin, artemetin, eupatolitin 3-galactoside, quercetin 3-rhamnogalactoside, rutin, isorhamnetin 3-galactoside and eupatin 3-SO₃Ca_{$\text{1}\text{2}$}. B. dentata contains the new glycoside eupalitin 3-galactoside and nine known compounds: pectolinarigenin, salvigenin, eupafolin, cirsiliol, eupatorin, eupatolitin, eupatolitin 3-glucoside, eupatolitin 3-galactoside and eupatin.     

A methylated flavone from Artemisia mesatlantica

From the aerial parts of Artemisia mesatlantica, a new highly methoxylated flavone was isolated. Its structure was determined by spectroscopic methods as 5,4′-dihydroxy-6,7,3′,5′-tetramethoxyflavone.     

Three highly oxygenated flavone glucuronides in leaves of Spinacia oleracea

Droplet counter-current chromatographic separation and subsequent TLC demonstrated the existence of at least 14 phenolics in the leaves of Spinacia oleracea. Three have now been isolated and identified, respectively, as the 4′-glucuronides of 5,7,4'-trihydroxy-3,6,3′-trimethoxyflavone (jaceidin), 5,3′,4′-trihydroxy-3-methoxy-6:7-methylene-dioxyflavone and 5,4′-dihydroxy-3,3′-dimethoxy-6:7-methylenedioxyflavone.     

Flavonoids of geigeria

Chromatographic separation of the ethanol extract of Geigeria burkei resulted in the isolation and characterization of two known flavonoids, 5,7,3′,4′-tetrahydroxy-6-methoxyflavone and 5,7,4'-trihydroxy-6 methoxyflavone. ¹³CNMR data, as well as the respiratory inhibition and uncoupling of oxidative phosphorylation, is reported for the first time.     

Octasubstituted flavones from Ageratum houstonianum

Two new highly oxygenated flavones, were isolated from aerial parts of Ageratum houstonianum. Their structures were established as 3′-hydroxy-5,6,7,8,2′,4′,5′-heptamethoxyflavone and 5,3′-dihydroxy-6,7,8,2′,4′,5′-hexamethoxyflavone on the basis of spectral data and chemical degradation. The structure of the latter compound was confirmed by X-ray analysis.     

Three isoflavonoids from Iris germanica

From the rhizome of Iris germanica one new hexaoxygenated isoflavone, two new polyoxygenated isoflavone glucosides, the known isoflavonoids irisolidone, irigenin and iridin and acetovanillone, sitosterol, α-amyrin and β-amyrin were isolated. The structures of the new compounds were established by chemical and spectroscopic means and by correlation with known constitutents.     

Isoflavonoids from Phaseolus coccineus

After treatment with CuCl₂, the following isoflavonoids have been isolated from the runner bean, Phaseolus coccineus: daidzein, genistein, isoprunetin, 2′-hydroxygenistein, phaseoluteone, 2′-hydroxydihydrodaidzein, isoferreirin, kievitone, cyclokievitone, glycinol, phaseollidin, phaseollin, demethylvestitol, phaseollinisoflavan, 2′-hydroxyisoprunetin and 7,4′-dihydroxy-5,2′-dimethoxyisoflavanone. The latter two compounds are novel natural products.     

Isolation and synthesis of two new flavones from Conoclinium coelestinum

Two new flavones, 3′,4′-methylenedioxy-5,6,7,8,5′-pentamethoxyflavone and 5,7,4′-trihydroxy-6,3′,5′-trimethoxyflavone, have been isolated from Conoclinium coelestinum. Final structure proof was accomplished by synthesis.     

The structure and synthesis of neobavachalcone,a new component of Psoralea corylifolia.

Reinvestigation of the seeds of P. corylifolia has given, besides known compounds, a new formylated chalcone named neobavachalcone whose structure has been deduced as 5′-formyl-2′,4-dihydroxy-4′-methoxychalcone from spectral data and confirmed by synthesis. Its dimethyl ether has also been synthesised by an alternative procedure.     

Chalcone glycosides of Antirrhinum majus

Three chalcones have been found in yellow flowers of A. majus, two of which have been identified as chalcononaringenin 4′-glucoside and 3,4,2′,4′,6′-pentahydroxychalcone 4′-glucoside.