Two methylated flavones from Artemisia frigida

Two new highly oxygenated flavones were isolated from Artemisia frigida. Their structures were determined by spectroscopic methods as 5,7,4′-trihydroxy-6,3′,5′-trimethoxyflavone and 5,7,3′-trihydroxy-6,4′,5′-trimethoxyflavone.     

Six 2′-hydroxyflavonols from Gutierrezia microcephala

Six 2′-hydroxyflavonols were isolated from Gutierrezia microcephala, including four new compounds, 5,7,2′-trihydroxy-3,6,4′,5′-tetramethoxyflavone, 5,7,2′-trihydroxy-3,6,8,4′,5′-pentamethoxyflavone, 5,2′-dihydroxy-3,6,7,8,4′,5′-hexamethoxyflavone and 5,7,2′,4′-tetrahydroxy-3,8,5′-trimethxoyflavone and two known compounds, 5,7,2′,5′-tetrahydroxy-3,6,8,4′-tetramethoxyflavone and 5,7,2′,4′-tetrahydroxy-3,6,8,5′-tetramethoxyflavone.     

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     

Brickellin,a novel flavone from brickellia veronicaefolia and b. chlorolepis

A new highly oxygenated flavone methyl ether has been isolated from Brickellia veronicaefolia and B. chlorolepis. It has been identified as 5,6′-dihydroxy-6,7,2′,3′,4′-pentamethoxyflavone and given the name brickellin.     

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.     

Isoflavones from Virola caducifolia

The Myristicaceae must be added to the small number of families which contain isoflavonoids; the previously unknown 5,7,2′-trihydroxy-4′-methoxyisoflavone and 5,7-dihydroxy-2′,4′-dimethoxyisoflavone having been found to co-occur with biochanin A in Virola caducifolia W. Rodr.     

5,7-dihydroxy-3,8,3′,4′-tetramethoxyflavone from Parastrephia quadrangularis

A new flavone has been isolated from Parastrephia quadrangularis and identified as 5,7-dihydroxy-3,8,3′,4′-tetramethoxyflavone.     

11,13-Dehydrodesacetylmatricarin and other sesquiterpene lactones from Artemisia ludoviciana var. Ludoviciana and the identity of artecanin and chyrsartemin B

11,13-Dehydrodesacetylmatricarin, achillin, parishin-C, vulgarin and artecanin were isolated from A. ludoviciana var. ludoviciana. The identity of artecanin and chrysartemin-B was confirmed and ¹³ C NMR and ¹H NMR data are described.     

Flavonoids from the exudate of Acacia neovernicosa

2′,4′-Dihydroxychalcone, 4′-hydroxy-2′-methoxychalcone and 2′,4′-dihydroxy-3′-methoxychalcone were isolated and characterized from the resinous exudate produced by Acacia neovernicosa. Smaller amounts of isoliquiritigenin, pinocembrin and chrysin were also found and identified by their chromatographic properties and UV spectra. The material of one collection contained galangin, 3-methylkaempferol and 3,3′ -dimethylquercetin.     

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.     

Flavonoids from Dodonaea viscosa

An investigation of Dodonaea viscosa afforded a new flavonoid having an isoprenoid side chain along with the seven known flavonoids: 5-hydroxy-3,6,     

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.     

Phenolics from the seeds of Argemone mexicana

Two new phenolic compounds, 5, 7, 2′, 6′-tetrahydroxyflavone and 5, 7-dihydroxychromone 7- neohesperidoside have been characterized from the seeds of Argemone mexicana.     

Ludalbin,a new lactone from Artemisia ludoviciana

Artemisia ludoviciana Nutt. ssp. albula (Woot.) Keck, a member of the vulgaris complex, contains a sesquiterpene lactone, ludalbin, which is 8-α-acetoxydouglanine.     

Dihydrochalcones from lindera umbellata

Two dihydrochalcones, 2′,6′-dihydroxy-4′-methoxydihydrochalcone and 2,4′,6′-trihydroxydihydrochalcone have been isolated from leaves of Lindera umbellata.     

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.