A series of crown ether derivatives containing a biphenyl or cholesteryl moiety have been synthesized for the first time. The structural effects of these compounds on the formation of liquid-crystalline phases are discussed. We have found that benzo crown ether derivatives bearing a p-cyano-or p-(octy1oxy) biphenyl moiety linked by an ester or ethyne group display a nematic liquid-crystalline phase, and 4'4 (cholesteryloxy) carbonyl) benzo crown ...