Regeln über Vorzeichen und Intensität von Cotton‐ Effekten von Tetraamminkupfer‐Zucker‐Komplexen

Abstract

Rules on Signs and Intensities of Cotton Effects of Tetraamminecopper Sugar ComplexesThe chromophore of the tetraamminecopper complex is best suited for configurational and conformational assignments of carbohydratcs by circular dichroism. According to our definition of the dihedral angle of neighbouring diol groups, the tetraamminecopper complexes of carbohydrates with a single 1,2-dihydroxy group with a positive sign of the angle exhibit a Cotton effect sequence -+ -, those with a negative sign of the angle exhibit a Cotton effect sequence + -+. The tetraamminecopper complexes with neighboured trio1 ligands with dihedral angles of the same sign exhibit the most intense Cotton effects; if the angles are of opposite sign, the rotational strengths are of relative low intensity. The maximal stability of the complexes is in the p H range of 11.1 to 11.4. The complex ratio of the tetraamminecopper complexes with 1,2,3-triol ligands is 1 : 1.

Circular Dichroism Studies on New Optically Active 1,5-Benzodiazepine Derivatives

“…In continuation of our circular dichroism studies on natural products and biologically active com pounds like carbohydrates [13][14][15][16][17][18][19][20][21], nucleosides and nucleotides [22][23][24][25][26], flavone glycosides [27][28][29], amino acids, peptides and proteins [30][31][32][33][34][35][36][37][38][39][40][41][42], steroids [43,44] or benzodiazepine derivatives [9,10,45], the UV-and CD-spectroscopic properties of thirty three new chiral benzodiazepine deriva tives are discussed in this communication.…”