Lipophilicity of teicoplanin antibiotics as assessed by reversed phase high-performance liquid chromatography:...

Structure-lipophilicity relationships of a large series of 63-COX teicoplanin antibiotic derivatives were examined, by correlating their capacity factors (log kw), measured through reversed-phase high-performance liquid chromatography on Deltabond C8 stationary phase, with some computed molecular properties such as fragmental log P constants (pi x), molecular volumes (Vx) and factors imparting hydrophilicity (e.g. amino groups in the X chain, nN). A number of equations were derived which demonstrate that variations of log kw are mainly related to changes in bulk (modelled by Vx) and polarity (primarily modelled by nN) of X chains of teicoplanin derivatives. QSAR analysis revealed that in-vitro activity against E. coli increases as lipophilicity decreases and isoelectric point increases.