Structure Identification: |
Phytochemistry . 2001 Jun;57(4):587-591. | Ellagic acid rhamnosides from the stem bark of Eucalyptus globulus[Pubmed: 11394863] | Four ellagic acid rhamnosides were isolated from the stem bark of Eucalyptus globulus. Their structures have been established on the basis of the analysis of their 1H NMR, 13C NMR, HMBC, IR and MS spectral data. The HMBC data of these compounds were most useful for their structure determinations, with these bring determined to be 3-O-Methylellagic acid 3'-O-alpha-rhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-3''-O-acetylrhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-2''-O-acetylrhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-4''-O-acetylrhamnopyranoside, respectively. Their antioxidant activities were evaluated by measuring the inhibition of lipid peroxidation using rat liver microsomes, with IC50 values of 10.0-14.0 microg/ml. | Nat Prod Res . 2014;28(4):230-238. | Isolation, characterisation and antibacterial activity of new compounds from methanolic extract of seeds of Caesalpinia crista L. (Caesalpinaceae)[Pubmed: 23822804] | Phytochemical study on the methanolic extract of Caesalpinia crista afforded two novel compounds, 2-hydroxytrideca-3,6-dienyl-pentanoate and octacosa-12,15-diene along with known compounds 3-O-methylellagic acid 3'O-α-rhamnopyranoside, β-sitosterol and sucrose. Compound 3-O-methylellagic acid 3'O-α-rhamnopyranoside is reported for the first time from the plant. Molecular structures, of isolated compounds, were elucidated by using the NMR spectroscopy in combination with IR and mass spectral data. All isolated compounds, extract and fractions were evaluated for in vitro antibacterial activity against various Gram-positive and Gram-negative bacterial strains and found to be significantly active against Staphylococcus aureus and methicillin-resistant S. aureus (minimum inhibitory concentration: 64-512 μg mL(- 1)). |
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