[Synthesis and antibacterial activity of benzoylaminoacyl-penicillins and related compounds with and without acylated catechol substituents].
Synthesis and Antibacterial Activity of Benzoylaminoacyl Penicillins and Related Compounds with and without Acylated Catechol Substituents. Syntheses of benzoyl, cinnamoyl, and benzoylhydrazido glyoxyloyl aminoacyl penicillins with and without acylated catechol substituents by condensation of corresponding acids or acylchlorides with ampicillin or amoxycillin and also of a 6-a-methoxy-derivative and corresponding esters are reported. Acylated catechol substituents improve the antibacterial activity against Gram-negative bacteria, especially against Pseudomonas strains and Salmonella. MIC tests of bacterial mutants with higher outer membrane penetrability and of the corresponding wild typs show that the increase of antibacterial activity by catechol substituents is caused by improvement of the penetration through the bacterial outer membran. The affinity to penicillin binding proteins is not influenced by catechol substituents. Stability against beta-lactamases is partly higher than that of azlocillin.