Water-soluble polymers bearing biologically active residues, 3. Hydrolysis of polyethers and poly(ether-ester)s bearing 1-naphthylacetyl groups
✍ Scribed by Milena Ignatova; Nevena Manolova; Iliya Rashkov; Maurice Sepulchre; Nicolas Spassky
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- English
- Weight
- 310 KB
- Volume
- 196
- Category
- Article
- ISSN
- 1022-1352
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✦ Synopsis
The hydrolysis of esters of naphthylacetic acid (NAA) and poly(ethy1ene glycol)s (PEG-NAAs) or poly[oxytartaroyloxypoly(oxyethylene)]s (PTEG-NAAs) was studied at pHs 9,2, 7,l and 43. The hydrolysis of complexes of PEG-NAA with poly(rnethacry1ic acid) (PMA) was also studied. UV spectroscopy and GPC were used to follow the release of NAA and the changes in the molecular weight of the polymers. The hydrolysis of PEG-NAAs follows a first-order kinetics. The rate constants of hydrolysis of PEG,,-NAA are higher than those of PEG,,-NAA, and this is attributed to a shielding effect of the polymer chain. The hydrolysis of PTEG-NAA proceeds with release of NAA from the end-groups and the pendent groups as well as with scission of the main-chain ester groups. It is proposed that the very slow hydrolysis of complexes of PEG-NAA with PMA is due to the localization of naphthylacetyl groups in the hydrophobic domains of the polycomplexes. a) Part 2: cf. ref."). b, Current address: Centre de Recherche sur les Biopolymkres Artificiels, URA 1465, Faculte de Pharmacie, 15, av. C. Flahault, 34060 Montpellier, France. 0 1995, Hiithig 6r Wepf Verlag, Zug CCC 1022-1352/95/$10.00 ') K. 2. Gamburg, "Biochemistry of auxins and its action on the plant cells", (Russ.), Nauka, Novosibirsk 1976, p. 271