TY - JOUR A1 - Lutz, Werner K. A1 - Winkler, F. K. A1 - Dunitz, J. D. T1 - Crystal structure of the antibiotic monensin similarities and differences betweeen free acid and metal complex N2 - The structure of monensin, C36H620 11 , has been deterrnined by X-ray analysis of its crystalline monohydrate (orthorhombic, a = 15.15, b = 23.61, c = 10.65 A, Z = 4, space group P212121). Phases were assigned by direct methods, malring use of the 'tangent formula'. Although the conformation of the free acid resembles that of the silver salt in being cyclic, there are differences in the hydrogen bonding pattern. These featurcs are discussed in relation to the cornplexation of metal ions by m.onensin. KW - Toxikologie Y1 - 1971 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61228 ER - TY - JOUR A1 - Lutz, Werner K. A1 - Früh, P. U. A1 - Simon, W. T1 - Microcalorimetric determination of ΔH0, ΔG0 and ΔS0 for the interaction of the carrier antibiotics nigericin and monensin with sodium and potassium ions N2 - The thermodynainic parameters ΔH0, ΔG0 and ΔS0 - and thereby the equilibrium constants - for the complexation of the carrier antibiotics nigericin and monensin with sodium and potassium ions in methanol at 25°C have been determined by microcalorimetry. Tbc results are discussed in terms of the nature of the interaction between ligands and cations. KW - Toxikologie Y1 - 1971 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-61218 ER -