Lipophilic 1,3-xylyl-21-crown-6 macrocyclic polyether 2-carboxylic acids as biological mimics of the ionophore antibiotics.

Twelve lipophilic 1,3-xylyl-21-crown-6 macrocyclic polyether 2-carboxylic acids, two lariat ether 1,3-xylyl-21-crown-6 macrocyclic polyether 2-carboxylic acids, and two 1,3-xylyl-28-crown-8 macrocyclic polyether 2-carboxylic acids were synthesized and tested for in vitro antibacterial activity, in vitro stimulation of rumen propionic acid production, and in vivo anticoccidial activity in chickens