Norbergenin derivatives from the stem bark of Diospyros sanza-minika (Ebenaceae) and their radical scavenging activity

Norbergenin Derivatives from Diospyros crassiflora (Ebenaceae)

“…Previous phytochemical studies on this plant have resulted in the isolation and characterization of new coumarins, namely crassiflorone, diosfeboside A and diosfeboside B [8,9]. In continuation of this study, we investigated the chloroform and ethyl acetate extracts of the stems of D. crassiflora, which led to the isolation of three new norbergenin derivatives (1)(2)(3), along with ten known compounds (4)(5)(6)(7)(8)(9)(10)(11)(12)(13). This paper deals with the structural elucidation of the new compounds, as well as the preliminary evaluation of the antioxidant properties of some isolates, especially of their ability to protect PC12 cells against hydrogen peroxide induced injury.…”

“…The UV spectrum showed maxima at 218 and 280 nm in methanol. The 1 H NMR spectrum displayed signals of a norbergenin nucleus, namely an aromatic methine at δ H 6.95 (1H, s), a substituted methylene at δ H 4.66 and 4.37 (1H each, m), and five aliphatic sp 3 oxymethines at δ H 5.24 (1H, d, J = 9.9 Hz), 4.35 (1H, m), 5.51 (1H, t, J = 9.9 Hz), 3.71(1H, t, J = 9.9 Hz), and 4.06 (1H, m), respectively [13]. The spectrum also showed characteristic signals of two galloyl groups at δ H 7.00 and δ H 7.04, respectively (2H each, s).…”

Analgesic and anti-inflammatory activities of 11-O-galloylbergenin

“…So far bergenin derivatives have been found negative for their cytotoxicity studies. Additionally bergenin and/or its derivatives have proven their cytoprotective profile in various studies (Goel et al, 1997;Kim et al, 2000;Lim et al, 2000a,b;Tangmouo et al, 2009). In conclusion 11-O-galloylbergenin has the strong potential to be developed further as a potential analgesic and anti-inflammatory lead compound.…”

Antimalarial activity of extract and norbergenin derivatives from the stem bark of Diospyros sanza‐minika A. Chevalier (Ebenaceae)

“…Fractions 31-35 and 70-75 were repurifi ed by CC over RP-18 using MeOH-H 2 O (30-70) to give respectively 191.7 mg of 11-O-p-hydroxybenzoylnorbergenin (3) and 335.1 mg of 4-O-(3′-methylgalloyl)norbergenin (4). These compounds have been identifi ed from their spectroscopic data (Mebe and Makuhunga, 1992;Tangmouo et al, 2009).…”

“…While no traditional medicinal uses have been described for Diospyros sanza-minika, extracts of some other Diospyros species showed signifi cant antimalarial potential (Likhitwitayawuid et al, 1999;Ma et al, 2008;Kantamreddi and Wright, 2008). Previous evaluations of the therapeutic potential of Diospyros sanza-minika were limited only to their antioxidant properties (Tangmouo et al, 2009). …”