Abstract: Polyphenol derivative compositions including oligomer or polymer esters containing N+2 monomer moieties, whose monomer moieties correspond to the following formula ##STR1## in which N is a number from 0 to 100, A represents a group --OR, a hydrogen atom or a substituent R, at least a majority of the substituents R represent a group --COR.sub.1, R.sub.1 is a saturated or unsaturated, linear or branched alkyl radical of at least two carbon atoms, or an aryl, aralkyl or aralkylene radical, a remainder of the substituents R is a hydrogen atom, an alkyl group, an acyl group --CO--C.sub.6 H.sub.2 --(OH).sub.3, a monosaccharide or a polysaccharide, and n.sub.1 and n.sub.2, which are identical to or different from each other, are numbers from 1 to 3, corresponding to the number of substitutions on a ring, and the diastereoisomers and the regioisomers of said monomer moieties, whereby the monomer moieties are connected by carbon--carbon bonds or by ether bridges between the rings which make up a flavan ring system.