Вид документа : Статья из журнала Шифр издания : 54/C 74 Автор(ы) : Skorik Yu. A., Gomes C. A. R. , Podberezskaya N. V. , Romanenko G. V., Pinto L. F., Yatluk Yu. G. Заглавие : Complexation models of N-(2-carboxyethyl)chitosans with copper(II) ions Место публикации : Biomacromolecules. - 2005. - Vol. 6, № 1. - С. 189-195. - ISSN 1525-7797. - ISSN 1525-7797 ББК : 54 Предметные рубрики: ХИМИЧЕСКИЕ НАУКИ Аннотация: The copper(II) complex formation equilibria of N-(2-carboxyethyl)chitosans with three different degrees of substitution (DS = 0.42, 0.92, and 1.61) were studied in aqueous solution by pH-potentiometric and UV-spectrophotometric techniques. It was demonstrated that the complexation model of CE-chitosans depends on DS: the [Cu(Glc-NR2)2] complexes are predominant for two lower substituted samples ("bridge model", log ?12 = 10.06 and 11.6, respectively), whereas the increase of DS leads to formation mainly of the [Cu(Glc-NR2)] complexes ("pendant model", log ?11 = 6.41). As a model for copper complexation with a disubstituted residue of CE-chitosan, the complex of N-methyliminodipropionate [CuMidp(H2O)]·(H2O) was synthesized and structurally characterized by XRD. The unit cell consists of two crystallographically nonequivalent Cu atoms having slightly distorted square pyramidal coordination; Midp constitutes the basal plane of the pyramid and acts as a tetradentate NO3 chelate-bridging ligand by the formation of two six-membered chelate rings (average Cu-O 1.99 A, Cu-N 2.04 A) and a bridge via carbonyl O atom (average Cu-O 1.99 A), an apical position is occupied by a water molecule (average Cu-Ow 2.30 A). Держатели документа: Центральная научная библиотека УрО РАН Доп.точки доступа: Skorik, Yu. A.; Gomes, C. A. R. ; Podberezskaya, N. V. ; Romanenko, G. V.; Pinto, L. F.; Yatluk, Yu. G.