Three new ellagic acid derivatives from the bark of Eschweilera coriacea from the Suriname rainforest.
Bioassay-guided fractionation of Eschweilera coriacea collected in the lowland wet forest of Suriname yielded the new but only weakly active ellagic acid derivative eschweilenol A (1) and the two new but inactive ellagic acid derivatives eschweilenol B (2) and eschweilenol C (3). The four known compounds, sucrose, ellagic acid, 3-O-galloylepigallocatechin, and epigallocatechin, were also isolated. The structures of the three new compounds were determined by spectrometric methods, primarily from the HMQC, HMBC, NOESY, and ROESY NMR techniques, and chemical methods, including methylation and triethylsilylation. The location of a hydroxyl group in one ellagic acid derivative was determined by a new technique involving an NOE correlation of the protons of a triethylsilyl derivative with a proton on a neighboring aromatic ring.
Department of Chemistry, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061-0212, USA.
S W
SW
Yang
B N
BN
Zhou
J H
JH
Wisse
R
R
Evans
H
H
van der Werff
J S
JS
Miller
D G
DG
Kingston
D000935:Antifungal Agents / Q000494:pharmacology; D002240:Carbohydrate Sequence; D002855:Chromatography, Thin Layer; D004610:Ellagic Acid / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D019441:Plant Epidermis / Q000737:chemistry*; D010946:Plants, Medicinal / Q000737:chemistry*; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013056:Spectrophotometry, Ultraviolet; D013532:Suriname; D015003:Yeasts / Q000187:drug effects
D000935:Antifungal Agents; D004610:Ellagic Acid