Furanoflavones and other chemical constituents of Lonchocarpus obtusos

Abstract

isolados das cascas das raízes de Lonchocarpus obtusos (Leguminosae). As estruturas de todos os compostos isolados foram determinadas usando métodos espectrométricos tais como RMN 1D e 2D (COSY, HSQC e HMBC) e EMAR, além da comparação com dados espectrais descritos na literatura para compostos de estruturas semelhantes.Two new furanoflavonoids, 5-hydroxy-2''-isopropenyl-3-methoxyfurane-(2",3":7,8)-flavone and 5-hydroxy-2''-(1-hydroxy-1-methylethyl)-3-methoxyfurane-(2",3":7,8)-flavone, along with thirteen other known compounds, were isolated from the root barks of Lonchocarpus obtusus (Leguminosae). The structures of all compounds were determined by spectrometric methods such as 1D and 2D NMR (COSY, HSQC and HMBC) and HREISMS beside comparison with spectral data for similar compounds.

Chemical composition and antioxidant activity of a Lebanese plant Euphorbia macroclada schyzoceras

“…Carbonyl group at the carbon atom C4 was confirmed by 13 C NMR at 178 or 177 mg/L, and as it was showed in MS-ESI, the ions at m/z 367, 339 and 311 were observed, which is attributed to the loss of CO and 2CO respectively. Detailed analysis of 2D NMR spectral data of 6 revealed and affirmed the correlation between these protons for each compound (Figure 2) [20][21][22] . This NMR spectral data (Proton and COSY) combined with the infrared suggested the presence of a flavone derive (Figure 3).…”

Antibacterial and Antioxidant Activities of Derriobtusone A Isolated fromLonchocarpus obtusus

“…Derriobtusone A was isolated as described previously by Cavalcante et al [ 22 ]. Dried root bark (720 g) and wood (750 g) of Lonchocarpus obtusus were powdered and then extracted at room temperature with n-hexane (3 × 2.0 L).…”

“…Lonchocarpus is a genus of the family Leguminosae, subfamily Papilionoideae, and it is prevalent in tropical and subtropical regions, including Brazil [20, 22]. …”

“…Some studies have reported that plants of the genus Lonchocarpus are able to produce compounds, such as alkaloids and triterpenoids, derived from benzoic acids and flavonoids [ 18 – 22 ]. Lonchocarpus is a genus of the family Leguminosae, subfamily Papilionoideae, and it is prevalent in tropical and subtropical regions, including Brazil [ 20 , 22 ].…”