Showing papers by "Maria Auxiliadora Coelho Kaplan published in 1996"
TL;DR: Three new phloroglucinols have been isolated from a petrol extract of the leaves and flowers of Hypericum brasiliense by spectroscopic methods including two-dimensional-NMR heteronuclear correlations.
75 citations
TL;DR: In this paper, three known phloroglucinols (japonicine A, uliginosin A and isouliginosin B) and a new phlorocolucinol (hyperbrasilol A) have been isolated from a petrol extract of the leaves and flowers of Hypericum brasiliense.
Abstract: Three known phloroglucinols (japonicine A, uliginosin A and isouliginosin B) and a new phloroglucinol (hyperbrasilol A) have been isolated from a petrol extract of the leaves and flowers of Hypericum brasiliense. Their structures were established by spectroscopic methods (UV, DCI-MS, 1H and 13C NMR, including SINEPT, HMBC, HSQC, DQFCOSY experiments). The substitution pattern of hyperbrasilol A was confirmed by X-ray crystallography. All four phloroglucinols were antibacterial against Bacillus subtilis in a TLC bioautographic assay. The flavonoids, kaempferol, luteolin, quercetin, quercitrin, isoquercitrin, hyperoside and guaijaverin, were isolated from a methanol extract of the same organs.
33 citations
Journal Article•
1 citations