4-O-ß-D-Glucosides of Hydroxybenzoic and Hydroxycinnamic Acids — Their Synthesis and Determination in Berry Fruit and Vegetable

The derivatives of hydroxybenzoic and hy­ droxycinnamic acids are widespread in the plant kingdom. A considerable number of these deriva­ tives are well known [1], Nevertheless there is only little existing information about the glucosides of these compounds and their distribution. Syringic acid-O-ß-D-glucoside was detected in Anodendron affine. [2], as well as /»-hydroxybenzoic acid-O-ß-D-glucoside in a great number of Apiaceae [3]. Protocatechuic acid-4-O-ß-D-glucoside was found in cockroaches of Periplaneta americana and Blatta orientalis [4], The glucosides of hydroxycinnamic acids also could be detected in plants. The O-ß-D-glucosides of p-coumaric and ferulic acid were found in the need­ les of Conifers besides the glucosides of /?-hydroxybenzoic, protocatechuic and vanillic acid [5—8]. But these compounds were not completely characterized. Furthermore the glucosides of caffeic, p-coumaric and ferulic acid were detected in tobacco [9] and in tomatoes [10—12]. To acquine further information about the distribu­ tion of the 4-O-ß-D-glucosides of the hydroxybenzoic and hydroxycinnamic acids we synthesized these compounds. The substances were characterized by UV, ‘H NMR, I3C NMR and FAB-MS. This process was necessary to obtain pure and authentic reference substances for HPLC and GC. Additionally the paper reports on the quantitative determination of these glucosides in fruit and vegetable.