7,2′,4′-Trihydroxy-3′-methoxyisoflavone from zollernia paraensis

Three further compounds have been isolated from Zollernia paraensis: 2,7-dihydroxy-4′-methoxy-3-phenylcoumarin, (±)-5,7-dihydroxy-2′,4′-dimethoxyisoflavanone and the new 7,2′,4′-trihydroxy-3′-methoxyisoflavone.     

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.     

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.     

Lectin variability in Phaseolus coccineus

Lectin variability within Phaseolus coccineus is revealed by non-denatured electrophoretic patterns and immunological labelling of total seed protein extracts, showing that the different cultivars and wild varieties studied can be classified into three main categories according to the number of isolectins (three, two or one) present in each extract. Attempts in the purification of these isolectins were performed on three different affinity systems in which ligands were thyroglobulin (known to purify the P. vulgaris isolectins), pig red cell membrane ghosts (stroma) or antibodies against the P. vulgaris cv. Contender E₂L₂ isolectin. The P. coccineus isolectins exhibit varied affinities towards thyroglobulin and stroma, the cathodic and anodic (pH 4.5) isolectins being respectively retained by the two systems, whereas the antibody affinity system is the only one able to purify the totality of the isolectins present in an extract.     

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.     

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.     

Characterization of gibberellins from light-grown Phaseolus coccineus seedlings by combined GC-MS

Following extensive purification of an extract from 5000 light-grown Phaseolus coccineus seedlings by procedures including countercurrent distribution, Sephadex G10, polyvinylpyrrolidone, charcoal-celite and silicic acid partition column chromatography, TLC preparative GLC, gibberellins A₁, A₄, A₅ and A₂₀ were characterized by combined GC-MS. In addition, an unknown compound isomeric with gibberellin A₁₇ but lacking an hydroxyl group, was also detected.     

Amorphastilbol,an antimicrobial agent from Amorpha nana

Bioassay-directed fractionation of Amorpha nana demonstrated that the anti Gram positive/antitubercular constituent is amorphastilbol. The chemical structure of amorphastilbol was confirmed by chemical transformation to known (Radula variabilis) dihydroamorphastilbol and its methyl ether. Inactive 3,5-dihydroxy-7,4′-dimethoxyflavone was detected in this plant for the first time and identified by interconversion with kaempferol. All compounds were evaluated in vitro for antimicrobial spectrum and potency.     

Isoflavones and stilbenes from Juniperus macropoda

An ethanolic extract of Juniperus macropoda, after chromatography, yielded three isoflavones, viz.irigenin, iridin and a new compound. In addition two stilbenes, resveratrol and piceid (resveratrol-3-O-β-D-glucoside), were isolated and characterized.     

Isoflavones from Xanthocercis zambesiaca

In addition to the previously described 7-hydroxy-8,4′-dimethoxy- and 7,3′-dihydroxy-8,4′-dimethoxy-isoflavone the heartwood of Xanthocercis zambesiaca has been shown to contain 7-hydroxy-8,3′,4′-trimethoxy-,3′,4′-dimethoxy-6,7-methylenedioxy- and 8,3′,4′-trimethoxy-6,7-methylenedioxy-isoflavone. A technique of determining isoflavone hydroxylation patterns by deuterium labelling is described.     

Auriculoside,a new flavan glycoside from Acacia auriculiformis

The structural elucidation of auriculoside, a new flavan glucoside from Acacia auriculiformis, is described. This is the third report of a flavan glycoside unsubstituted in the heterocyclic ring.     

Viridiflorin,an isoflavone from Tephrosia viridiflora

A new isoflavone, viridiflorin, has been isolated from Tephrosia viridiflora. Its structure was established as 4′,5,7-trihydroxy-2′,5′-dimethoxy-6-prenylisoflavone based on spectral evidence and chemical transformation.     

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.     

Kaurene and kaurenol biosynthesis in cell-free system of Phaseolus coccineus suspensor

It is shown that suspensor tissue of Phaseolus coccineus can biosynthesize ent-kaur-16-ene and ent-kaur-16-en-19β-ol, two key precursors in the biosynthesis of gibberellins.     

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.     

Novel 2′-substituted flavonols from the farinose exudate of Notholaena affinis

The farinose exudate produced on the undersurface of fronds of Notholaena affinis consists of a variety of lipophilic flavonol aglycones. Four of these have been identified as novel interrelated compounds. They all bear methoxyl groups in positions 3,6,7,8 and hydroxyl and/or methoxyl groups at 2′,4′.     

2,4,2′-Trihydroxy-4′-methoxybenzil from Zollernia paraensis

A new phenolic compound, isolated from the wood of Zollernia paraensis, has been shown to be 2,4,2′-trihydroxy-4′-methoxybenzil by spectral data and synthesis.