Five chitosan derivatives, i.e. O-butyryl chitosan, O-benzoyl chitosan, N-phthaloyl chitosan, N-maleoyl chitosan and O-cyanoethyl chitosan, were prepared from c
Optically active copolyesters based on axially dissymmetric 1,1’-binaphthalene-2,2’-diyl units have been preparedand characterized by specific rotation, <sup>