Studies On Chemical Modification Of Monensin. V. Synthesis, Sodium Ion Permeability, Antibacterial Activity, And Crystal Structure Of 7-0-(4-Substituted Benzyl)Monensins

Abstract

7-0-(4-Substituted benzyl)monensins (3a—g) were synthesized from monensin (1), and their lipophilicity, antibacterial activity, and Na+ ion permeability were examined. 7-0-(4-Ethylbenzyl)monensin (3e) showed the largest Na+ ion permeability, but 3c,f,g showed smaller Na+ ion permeability than 7-O-benzylmonensin (2) in spite of higher lipophilicity. An X-ray study of the sodium salt of 3e revealed that the benzyl group was located over the position between the D and E rings, and that the ethyl substituent on the benzyl group was close to the C(28) methyl group on the E ring. © 1994, The Pharmaceutical Society of Japan. All rights reserved.