BIOLOGICALLY ACTIVE POLY[3-(3,4-DIHYDROXYPHENYL)GLYCERIC ACID]FROM BORAGO OFFICINALIS(BORAGINACEAE
In previous publications we reported that the main chem-ical constituent of high molecular water-soluble preparationsfrom Symphytum asperum, S. caucasicum,S. officinale, S.grandiflorum,Anchusa italica and Cynoglossum officinale(Boraginaceae) was biologically activecaffeic acid-derivedpolymer, namelypoly[oxy-1-carboxy-2-(3,4-dihydroxy-phenyl)ethylene] that is poly[3-(3,4-dihydroxy-phenyl) glyc-eric acid] (PDPGA) [1-5]. The polyoxyethylene chain is thebackbone of this polymer molecule with 3-(3,4-dihydroxyphenyl)glyceric acid residue as the repeating unit(Fig. N1). This compound represents a new class of naturalpolyethers. Within the field of pharmacologically activebiopolymers the area of stable polyethers seems rather newand attractive. PDPGA as a unique natural polyether con-tains aliphatic ether groups in its polymer backbone. PDP-GA is endowed with intriguing in vitro and in vivo pharma-cological properties: anti-inflammatory, antioxidant, anticom-plementary and anticancer [6-8].