Physicochemical properties of β3-lactam antibiotics: Oil-water distribution

✍ Scribed by Akira Tsuji; Osamu Kubo; Etsuko Miyamoto; Tsukinaka Yamana

• Publisher: John Wiley and Sons
• Year: 1977
• Tongue: English
• Weight: 505 KB
• Volume: 66
• Category: Article
• ISSN: 0022-3549
• DOI: 10.1002/jps.2600661205

✦ Synopsis

Apparent partition coefficients Papp, of beta-lactam antibiotics were determined in octanol-water and 2-methylpropanol-water systems at various pH values. The pKa values also were determined by potentiometry under the conditions of partition experiments. The intrinsic partition coefficients for the unionized form, Pu, and the ionized form, Pi, of beta-lactam antibiotics were calculated from the equation Papp = Pu[aH+/(Ka + aH+)] + Pi[Ka/(Ka + aH+)]. The correlation between Pu and Pi values and lipophilic parameters of penicillins measured in other systems was examined.