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Vakhtang Barbakadze
The caffeic acid-derived biopolymers from medicative plants comfrey and bugloss were isolated that represent a replacement category of natural polyethers. consistent with 13C-, 1H-NMR, APT, second heteronuclear 1H/13C HSQC, 1D NOE and second DOSY experiments the polyoxyethylene chain is that the backbone of the chemical compound molecule. 3,4-Dihydroxyphenyl and carboxyl teams ar regular substituents at 2 carbon atoms within the chain. The continuance unit of this regular chemical compound is 3-(3,4- dihydroxyphenyl)-glyceric acid residue. Thus, the structure of natural chemical compound was found to be poly[oxy-1-carboxy-2-(3,4- dihydroxyphenyl)ethylene] or poly[3-(3,4-dihydroxyphenyl)glyceric acid] (PDPGA). Then basic monomeric moiety of this chemical compound 3-(3,4-dihydroxyphenyl)glyceric acid was synthesized via Sharpless uneven dihydroxylation of trans-caffeic acid derivatives employing a K Os catalyst. Besides, alkyl PDPGA was obtained via ring gap polymerisation of 2-methoxycarbonyl-3-(3,4- dimethoxyphenyl)oxirane employing a cationic instigator.