Synthesis of 1-O-methylchlorogenic acid: reassignment of structure for MCGA3 isolated from bamboo (Phyllostachys edulis) leaves.
The first synthesis of 1-O-methylchlorogenic acid is described. The short and efficient synthesis of this compound provides laboratory-scale quantities of the material to investigate its biological properties. The synthesis involves C-1 alkylation of the known (-)-4,5-cyclohexylidenequinic acid lactone followed by methoxide opening to the hydroxyl ester. Acylation of the C-5 hydroxyl group followed by sequential removal of protecting groups afforded 1-O-methylchlorogenic acid. The NMR spectroscopic characteristics of this compound do not coincide with those reported for the original isolation from bamboo (Phyllostachys edulis) leaves of the compound designated MCGA3. Comparison of the published spectroscopic data reported for MCGA3, with both reported literature values and spectroscopic data obtained from an authentic sample, leads to the conclusion that the compound isolated from bamboo (Phyllostachys edulis) leaves is instead methyl chlorogenate.
US Dairy Forage Research Center, Agricultural Research Service, USDA, 1925 Linden Drive, Madison, Wisconsin 53706, United States.
Wayne E
WE
Zeller
D002726:Chlorogenic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry* / Q000378:metabolism*; D018515:Plant Leaves / Q000737:chemistry / Q000378:metabolism*; D006109:Poaceae / Q000737:chemistry / Q000378:metabolism*
D010936:Plant Extracts; D002726:Chlorogenic Acid; C417238:methyl chlorogenate