Sigmoidine L, A New Antibacterial Flavonoid from Erythrina Sigmoidea (Fabaceae)

Abstract

Chemical analyses of the stem bark of Erythrina sigmoidea (Fabaceae) yielded a new flavonoid, designated sigmoidin L (1), the known erythrinasinate, E-p-coumaric acid docosylester, and 3′-prenylnaringinin, reported here for the first time for the stem bark of E.sigmoidea. The structure of 1 was established by chemical and spectroscopic means as 5,7, 3′,4′-tetrahydroxy-5′-[3″-methyl-4″-oxobut-(1″Z) enyl]flavanone. Sigmoidin L exhibited significant antibacterial potency in vitro against Staphylococus aureus and Proteus vulgaris.

Optimization of Total Flavonoid Compound Extraction from Gynura medica Leaf Using Response Surface Methodology and Chemical Composition Analysis

“…Flavonoid compounds, which are a large group of secondary metabolites in higher plants [ 1 ], are known to be responsible for antioxidant [ 2 , 3 ], anticancer [ 4 , 5 ], anti-inflammatory [ 6 , 7 ], hepatoprotective potential [ 8 , 9 ] and antibacterial activity [ 10 , 11 ]. Recently, epidemiological studies have strongly suggested that consumption of plant flavonoids contributes to reducing the risk or incidence of some cancers [ 12 , 13 ].…”

Coumestan Glycosides from the Stem Bark of Cylicodiscus Gabunensis

“…According to the molecular formula, there was a second hydroxyl group in 1, which on a biogenetic basis was assumed to be at C-3 [3]. Furthermore, the 1 H and 13 C NMR data of the aglycone (Tables 1 and 2), as well as the IR and MS evidence (see Experimental), were consistent with structure 3.…”

“…The IR spectrum of 1 disclosed absorptions due to a δ-lactone carbonyl (1725 cm -1 ), aromatic ring (1625, 1604, 1500 cm -1 ) and aromatic C-O (1222 cm -1 ), as well as UV absorption maxima at 246, 315 and 353 nm, indicating the presence of a coumestan skeleton [1b,1f,2]. Furthermore, absorption bands at 3410-3200 cm -1 and the positive response to the FeCl 3 According to the molecular formula, there was a second hydroxyl group in 1, which on a biogenetic basis was assumed to be at C-3 [3]. Furthermore, the 1 H and 13 C NMR data of the aglycone (Tables 1 and 2), as well as the IR and MS evidence (see Experimental), were consistent with structure 3.…”

Flavanones from the Stem Bark of Erythrina Sigmoidea

“…Flavonoids have been known for a long time to exert diverse biological effects [1,2] and are widespread in the plant kingdom. The genus Erythrina (Fabaceae) has a significant history of folkloric use for the treatment of various diseases [3]. Previously we reported sigmoidin L [3], an anti-bacterial flavonoid from E. sigmoidea, a Cameroonian medicinal plant.…”

“…The genus Erythrina (Fabaceae) has a significant history of folkloric use for the treatment of various diseases [3]. Previously we reported sigmoidin L [3], an anti-bacterial flavonoid from E. sigmoidea, a Cameroonian medicinal plant. As a continuation of our phytochemical studies of the neutral compounds of this species, we now report the isolation and structural elucidation of two flavonoids, namely 5,7-dihydroxy-3′-O-prenyl-(3′′,4′′-dihydroxy-2′′,2′′-dimethylpyrano)[5′′,6′′:4′,5′]flavanone (1) and 5,7,3′-trihydroxy-(3′′-hydroxy-2′′-(1-hydroxyisopropyl)-[4′,5:4′′,5′′]furanoflavanone (2).…”