ABSTRACT
The phytochemical investigation of the crude methanolic extracts roots and stem bark of Anthonotha cladantha (Harms) J.Léonard led to the isolation and identification of twelve secondary metabolites: 2,3-dihydroxypropyl hexacosanoate (1), hederagenine (2), cycloeucalenol (3), 2α-hydroxylupeol (4), betulinic acid (5), lupeol (6), heptacosan-2-one (7), triacontanoic acid (8), stigmast-4-en-3-one (9), β-sitosterol (10), stigmasterol (11), and stigmasterol-3-O-β-D-glucopyranoside (12). Their structures were elucidated with the help of their spectroscopic and physical data and by comparison with those reported in the literature. To the best of our knowledge, from all those compounds, 2,3-dihydroxypropyl hexacosanoate (1), hederagenine (2), cycloeucalenol (3), 2α-hydroxylupeol (4), and betulinic acid (5) are being reported for the first time from this genus. In addition, the acetylation of compound 1 afforded a new derivative 3-(hexacosanoyloxy)propane-1,2-diyl diacetate (1a).Compound 1 possessed a moderate α-glucosidase inhibitory activity with an IC50 value of 39.2 ± 0.22 µM; it neither showed antioxidant activity nor inhibition against the enzyme urease. Compound 1a exhibited weak antioxidant activity in the DPPH assay with an IC50 value of 80.3 ± 0.83 μM but was inactive against α-glucosidase and urease. Furthermore, both compounds 1 and 1a were inactive against seven pathogenic bacterial strains.
ABSTRACT
he chemical investigation of the methanolic crude extract of leaves of Diospyros iturensis gave us 15 known secondary metabolites identified as mixture of α-amyrenone (1) and β-amyrenone (2), β-amyrin (3), mixture of β-sitosterol (4) and stigmasterol (5), betulin (6), uvaol (7), betulinic acid (8), ursolic acid (9), corosolic acid (10), actinidic acid (11),11-O-p-hydroxybenzoylbergenin (12), bergenin (13) and mixture of stigmasterol glucoside (14) and β-sitosterol glucoside (15) respectively. The structures of secondary metabolites were elucidated with the help of NMR and mass spectral data and by comparison of their spectral data with literature.Among the fifteen isolated compounds, four compounds were identified for the first time in Diospyros genus.These included uvaol (7), corosolic acid (10), actinidic acid (11) and 11-O-p-hydroxybenzoylbergenin (12).Crude methanolic extract of leaves and four isolated compounds including betulin (6), betulinic acid (8), 11-O-p-hydroxybenzoylbergenin (12) and bergenin (13) were evaluated for their antiproliferative activity against two cancer cell lines CAL-27 and NCI-H460 by the MTT assay, antioxidant potential and inhibitory activity against the lipoxygenase and urease enzymes, respectively. The results indicated that the methanolic crude extract of leaves exhibited moderate antioxidant activity and was inactive against the two cancer cell lines. Betulin (6),11-O-p-hydroxybenzoylbergenin (12) and bergenin (13) exhibited moderate antioxidant and lipoxygenase inhibition with IC 50 = 65.8, 85.6, 82.5 µM and IC50 = 58.5, 95.2, 76.2 µM, respectively. Furthermore, 11-O-p-hydroxybenzoylbergenin (12) and bergenin (13) exhibited moderate urease inhibition activity with IC50 values of 45.6 µM and 49.8 µM, respectively.
ABSTRACT
he chemical investigation of the methanolic crude extract of leaves of Diospyros iturensis gave us 15 known secondary metabolites identified as mixture of α-amyrenone (1) and β-amyrenone (2), β-amyrin (3), mixture of β-sitosterol (4) and stigmasterol (5), betulin (6), uvaol (7), betulinic acid (8), ursolic acid (9), corosolic acid (10), actinidic acid (11),11-O-p-hydroxybenzoylbergenin (12), bergenin (13) and mixture of stigmasterol glucoside (14) and β-sitosterol glucoside (15) respectively. The structures of secondary metabolites were elucidated with the help of NMR and mass spectral data and by comparison of their spectral data with literature.Among the fifteen isolated compounds, four compounds were identified for the first time in Diospyros genus.These included uvaol (7), corosolic acid (10), actinidic acid (11) and 11-O-p-hydroxybenzoylbergenin (12).Crude methanolic extract of leaves and four isolated compounds including betulin (6), betulinic acid (8), 11-O-p-hydroxybenzoylbergenin (12) and bergenin (13) were evaluated for their antiproliferative activity against two cancer cell lines CAL-27 and NCI-H460 by the MTT assay, antioxidant potential and inhibitory activity against the lipoxygenase and urease enzymes, respectively. The results indicated that the methanolic crude extract of leaves exhibited moderate antioxidant activity and was inactive against the two cancer cell lines. Betulin (6),11-O-p-hydroxybenzoylbergenin (12) and bergenin (13) exhibited moderate antioxidant and lipoxygenase inhibition with IC 50 = 65.8, 85.6, 82.5 µM and IC50 = 58.5, 95.2, 76.2 µM, respectively. Furthermore, 11-O-p-hydroxybenzoylbergenin (12) and bergenin (13) exhibited moderate urease inhibition activity with IC50 values of 45.6 µM and 49.8 µM, respectively.